FERC/DEIS-0255D

DRAFT MULTI-PROJECT ENVIRONMENTAL IMPACT STATEMENT

FOR HYDROPOWER LICENSES

Susquehanna River Hydroelectric Projects

York Haven Project—FERC Project No. 1888-030–Pennsylvania

Muddy Run Project—FERC Project No. 2355-018–Pennsylvania

Conowingo Project—FERC Project No. 405-106–Maryland/Pennsylvania

Federal Energy Regulatory Commission

Office of Energy Projects

Division of Hydropower Licensing

888 First Street, NE

Washington, D.C. 20426

Office of

Energy

Projects

July 2014
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FEDERAL ENERGY REGULATORY COMMISSION

WASHINGTON, D.C. 20426

OFFICE OF ENERGY PROJECTS

To the Agency or Individual Addressed:

Reference: Draft Environmental Impact Statement

Attached is the draft environmental impact statement (EIS) for the York Haven, 

Muddy Run, and Conowingo projects, collectively referred to as the Susquehanna River 

Projects (Nos. 1888-030, 2355-018, and 405-106), located on the Susquehanna River in 

York, Dauphin, and Lancaster counties in Pennsylvania and Cecil and Harford counties 

in Maryland.

This draft EIS documents the view of governmental agencies, non-governmental 

organizations, affected Indian tribes, the public, the license applicants, and Federal 

Energy Regulatory Commission (Commission or FERC) staff. It contains staff 

evaluations of the applicants’ proposals and the alternatives for relicensing each of the 

Susquehanna River Projects.

Before the Commission makes a licensing decision, it will take into account all 

concerns relevant to the public interest. The draft EIS will be part of the record from 

which the Commission will make its decision. The draft EIS was sent to the U.S. 

Environmental Protection Agency and made available to the public on or about 

July 30, 2014.

Copies of the draft EIS are available for review in the Commission’s Public 

Reference Branch, Room 2A, located at 888 First Street, N.E., Washington, D.C. 20426. 

The final EIS also may be viewed on the Internet at www.ferc.gov/docsfiling/elibrary.asp. Please call (202) 502-8222 for assistance.

Any comments should be filed by September 29, 2014. The Commission strongly 

encourages electronic filing. Please file comments using the Commission’s efiling 

system at http://www.ferc.gov/docs-filing/efiling.asp. Commenters can submit brief 

comments up to 6,000 characters, without prior registration, using the eComment system 

at http://www.ferc.gov/docs-filing/ecomment.asp. You must include your name and 

contact information at the end of your comments. For assistance, please contact FERC 

Online Support. In lieu of electronic filing, please send a paper copy to: Kimberly D. 

Bose, Secretary, Federal Energy Regulatory Commission, 888 First Street, NE, 

Washington, D.C. 20426. Please affix the project number(s) (Project No. 405-106, 

Project No. 2355-018, or Project No. 1888-030) to all comments.

Attachment: Draft Environmental Impact Statement
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iii

COVER SHEET

a. Title: Relicensing the York Haven, Muddy Run, and Conowingo

Projects, FERC Project Nos. 1888-030, 2355-018, and 405-106

b. Subject: Draft Environmental Impact Statement

c. Lead Agency: Federal Energy Regulatory Commission

d. Abstract: The existing projects are located on the Susquehanna River in York, 

Dauphin, and Lancaster counties in Pennsylvania, and Cecil and 

Harford counties in Maryland. Each project has one development,

and together they span about 55 river miles from the mouth of the 

Susquehanna River to upstream of the York Haven impoundment. 

The York Haven Power Company, LLC (York Haven Power), 

executed a Settlement Agreement pertaining to relicensing the York 

Haven Project among York Haven Power, U.S. Fish and Wildlife 

Service, the Commonwealth of Pennsylvania, Pennsylvania Fish 

and Boat Commission, Maryland Department of Natural Resources, 

and the Susquehanna River Basin Commission. The Settlement 

Agreement resolved all outstanding issues pertaining to project 

relicensing. 

Exelon Generation Company, LLC’s Muddy Run and Conowingo 

projects are located on the Susquehanna River in Lancaster and 

York counties, Pennsylvania, and Cecil and Harford counties, 

Maryland. Conowingo Pond acts as the lower reservoir for the 

Muddy Run Project. 

The three projects do not occupy any federal lands. 

The staff’s recommendation is to relicense the three projects as 

proposed, with certain modifications and additional measures 

recommended by the agencies. 

e. Contact: Emily Carter

Federal Energy Regulatory 

Commission

Office of Energy Projects

888 First Street, N.E.

Washington, D.C. 20426

(202) 502-6512
iv

f. Transmittal: This draft environmental impact statement to relicense the York 

Haven, Muddy Run, and Conowingo Hydroelectric Projects is being 

made available for public comment on or about July 30, 2014, as 

required by the National Environmental Policy Act of 19691 and the 

Commission’s Regulations Implementing the National 

Environmental Policy Act (18 CFR, Part 380).

 

1 National Environmental Policy Act of 1969, amended (Pub. L. 91-190. 42 U.S.C. 

4321-4347, January 1, 1970, as amended by Pub. L. 94-52, July 3, 1975, Pub. L. 94-83, 

August 9, 1975, and Pub. L. 97-258, §4(b), September 13, 1982).
v

FOREWORD

The Federal Energy Regulatory Commission (Commission), pursuant to the 

Federal Power Act (FPA)2 and the U.S. Department of Energy Organization Act3 is 

authorized to issue licenses for up to 50 years for the construction and operation of nonfederal hydroelectric development subject to its jurisdiction, on the necessary conditions:

That the project...shall be such as in the judgment of the Commission will be best 

adapted to a comprehensive plan for improving or developing a waterway or 

waterways for the use or benefit of interstate or foreign commerce, for the 

improvement and utilization of water-power development, for the adequate 

protection, mitigation, and enhancement of fish and wildlife (including related 

spawning grounds and habitat), and for other beneficial public uses, including 

irrigation, flood control, water supply, and recreational and other purposes referred 

to in section 4(e)...4

The Commission may require such other conditions not inconsistent with the FPA 

as may be found necessary to provide for the various public interests to be served by the 

project.5

 Compliance with such conditions during the licensing period is required. The 

Commission’s Rules of Practice and Procedure allow any person objecting to a licensee’s 

compliance or noncompliance with such conditions to file a complaint noting the basis 

for such objection for the Commission’s consideration.6

 

2 16 U.S.C. §791(a)-825r, as amended by the Electric Consumers Protection Act of 

1986, Public Law 99-495 (1986), the Energy Policy Act of 1992, Public Law 102-486 

(1992), and the Energy Policy Act of 2005, Pub. L. 109-58 (2005).

3 Public Law 95-91, 91 Stat. 556 (1977).

4 16 U.S.C. § 803(a).

5 16 U.S.C. § 803(g).

6 18 C.F.R. § 385.206 (2014).
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TABLE OF CONTENTS

COVER SHEET .................................................................................................................iii

FOREWORD....................................................................................................................... v

LIST OF FIGURES............................................................................................................ xi

LIST OF TABLES............................................................................................................xiii

ACRONYMS AND ABBREVIATIONS........................................................................xvii

EXECUTIVE SUMMARY.............................................................................................. xix

1.0 INTRODUCTION.................................................................................................... 1

1.1 APPLICATION............................................................................................. 1

1.2 PURPOSE OF ACTION AND NEED FOR POWER.................................. 3

1.2.1 Purpose of Action ............................................................................ 3

1.2.2 Need for Power................................................................................ 3

1.3 STATUTORY AND REGULATORY REQUIREMENTS ......................... 5

1.3.1 Federal Power Act ........................................................................... 7

1.3.1.1 Section 18 Fishway Prescriptions................................... 7

1.3.1.2 Section 10(j) Recommendations..................................... 7

1.3.2 Clean Water Act .............................................................................. 8

1.3.3 Endangered Species Act................................................................ 10

1.3.4 Coastal Zone Management Act ..................................................... 11

1.3.5 National Historic Preservation Act................................................ 12

1.3.6 Magnuson-Stevens Fishery Conservation and Management Act . 13

1.4 PUBLIC REVIEW AND COMMENT....................................................... 13

1.4.1 Scoping .......................................................................................... 13

1.4.2 Interventions.................................................................................. 15

1.4.3 Comments on the Application....................................................... 17

1.5 SETTLEMENT AGREEMENT ................................................................. 19

2.0 PROPOSED ACTIONS AND ALTERNATIVES ................................................ 21

2.1 NO-ACTION ALTERNATIVE.................................................................. 21

2.1.1 Existing Project Facilities.............................................................. 21

2.1.1.1 York Haven Project ...................................................... 21

2.1.1.2 Muddy Run Project....................................................... 25

2.1.1.3 Conowingo Project ....................................................... 28

2.1.2 Project Safety................................................................................. 31

2.1.3 Existing Project Operation ............................................................ 31

2.1.3.1 York Haven Project ...................................................... 31

2.1.3.2 Muddy Run Project....................................................... 32
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2.1.3.3 Conowingo Project ....................................................... 33

2.1.4 Existing Environmental Measures................................................. 34

2.1.4.1 York Haven Project ...................................................... 34

2.1.4.2 Muddy Run Project....................................................... 35

2.1.4.3 Conowingo Project ....................................................... 36

2.2 APPLICANTS’ PROPOSALS.................................................................... 36

2.2.1 Proposed Project Facilities............................................................ 36

2.2.2 Proposed Project Operation........................................................... 37

2.2.3 Proposed Environmental Measures............................................... 37

2.2.3.1 York Haven Project ...................................................... 37

2.2.3.2 Muddy Run Project....................................................... 41

2.2.3.3 Conowingo Project ....................................................... 44

2.2.4 Modifications to the Applicants’ Proposals – Mandatory 

Conditions...................................................................................... 49

2.3 STAFF ALTERNATIVE ............................................................................ 52

2.4 ALTERNATIVES CONSIDERED BUT ELIMINATED FROM 

DETAILED ANALYSIS ............................................................................ 55

2.4.1 Issuing a Non-Power License........................................................ 56

2.4.2 Federal Government Takeover of the Projects.............................. 56

2.4.3 Retiring the Project........................................................................ 56

3.0 ENVIRONMENTAL EFFECTS............................................................................ 57

3.1 GENERAL DESCRIPTION OF THE RIVER BASIN .............................. 57

3.2 CUMULATIVELY AFFECTED RESOURCES........................................ 58

3.2.1 Geographic Scope.......................................................................... 59

3.2.2 Temporal Scope............................................................................. 59

3.3 PROPOSED ACTION AND ACTION ALTERNATIVES ....................... 60

3.3.1 Geology and Soils.......................................................................... 60

3.3.1.1 Affected Environment................................................... 60

3.3.1.2 Environmental Effects .................................................. 64

3.3.1.3 Cumulative Effects ....................................................... 71

3.3.2 Water Resources............................................................................ 71

3.3.2.1 Affected Environment................................................... 71

3.3.2.2 Environmental Effects ................................................ 121

3.3.2.3 Cumulative Effects ..................................................... 192

3.3.3 Terrestrial Resources................................................................... 193

3.3.3.1 Affected Environment................................................. 193

3.3.3.2 Environmental Effects ................................................ 222

3.3.4 Threatened and Endangered Species........................................... 235

3.3.4.1 Affected Environment................................................. 235

3.3.4.2 Environment Effects................................................... 240

3.3.5 Recreation and Land Use Resources........................................... 243

3.3.5.1 Affected Environment................................................. 243
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3.3.5.2 Environmental Effects ................................................ 265

3.3.6 Cultural Resources....................................................................... 281

3.3.6.1 Affected Environment................................................. 281

3.3.6.2 Environmental Effects ................................................ 295

3.3.7 Aesthetic Resources..................................................................... 305

3.3.7.1 Affected Environment................................................. 305

3.3.7.2 Environmental Effects ................................................ 306

3.3.8 Socioeconomics........................................................................... 313

3.3.8.1 Affected Environment................................................. 313

3.3.8.2 Environmental Effects ................................................ 318

3.4 NO-ACTION ALTERNATIVE................................................................ 319

4.0 DEVELOPMENTAL ANALYSIS ...................................................................... 320

4.1 POWER AND DEVELOPMENTAL BENEFITS OF THE PROJECTS. 320

4.2 COMPARISON OF ALTERNATIVES.................................................... 323

4.2.1 No-Action Alternative ................................................................. 325

4.2.2 Applicants’ Proposals.................................................................. 326

4.2.3 Staff Alternative .......................................................................... 326

4.3 COST OF ENVIRONMENTAL MEASURES......................................... 327

5.0 CONCLUSIONS AND RECOMMENDATIONS............................................... 363

5.1 COMPREHENSIVE DEVELOPMENT AND RECOMMENDED 

ALTERNATIVE ....................................................................................... 363

5.1.1 York Haven Project ..................................................................... 364

5.1.1.1 Measures Proposed by York Haven Power ................ 364

5.1.1.2 Additional Measures Recommended by Staff for York 

Haven .......................................................................... 367

5.1.1.3 Measures Not Recommended ..................................... 374

5.1.2 Muddy Run Project...................................................................... 375

5.1.2.1 Measures Proposed by Exelon.................................... 375

5.1.2.2 Additional Measures Recommended by Staff for Muddy 

Run.............................................................................. 376

5.1.2.3 Measures Not Recommended ..................................... 382

5.1.3 Conowingo Project ...................................................................... 383

5.1.3.1 Measures Proposed by Exelon.................................... 383

5.1.3.2 Additional Measures Recommended by Staff for 

Conowingo.................................................................. 385

5.1.3.3 Measures Not Recommended ..................................... 400

5.2 UNAVOIDABLE ADVERSE EFFECTS................................................. 401

5.3 FISH AND WILDLIFE AGENCY RECOMMENDATIONS ................. 402

5.4 CONSISTENCY WITH COMPREHENSIVE PLANS............................ 413

6.0 LITERATURE CITED......................................................................................... 416
x

7.0 LIST OF PREPARERS........................................................................................ 428

8.0 LIST OF RECIPIENTS........................................................................................ 430

APPENDIX A – Draft License Articles – York Haven Hydroelectric Project

APPENDIX B – Draft License Articles – Muddy Run Pumped Storage Project 

APPENDIX C – Draft License Articles – Conowingo Hydroelectric Project’

APPENDIX D – Preliminary Fishway Prescription – York Haven Hydroelectric Project 

APPENDIX E – Preliminary Fishway Prescription – Muddy Run Pumped Storage Project

APPENDIX F – Preliminary Fishway Prescription – Conowingo Hydroelectric Project

APPENDIX G – Water Quality Certification – Muddy Run Pumped Storage Project
xi

LIST OF FIGURES

Figure 1-1. Susquehanna River Projects location ............................................................ 2

Figure 2-1. Location and project boundaries for lower Susquehanna Projects ............. 22

Figure 2-2. Project facilities for the York Haven Project .............................................. 23

Figure 2-3. Project facilities for the Muddy Run Project............................................... 26

Figure 2-4. Project facilities for the Conowingo Project ............................................... 29

Figure 3-1. Changes in vertical cross-sectional area for selected years and 

remaining sediment-storage capacity in Conowingo Pond......................... 63

Figure 3-2. Stream gages in the Susquehanna River Projects area................................ 74

Figure 3-3. Conowingo monthly pond elevations, January 2004 through 

December 2010............................................................................................ 79

Figure 3-4. Flow and stage variation at USGS gage no. 01578310 downstream of 

Conowingo dam .......................................................................................... 81

Figure 3-5. Typical impoundment and Conowingo tailrace flow fluctuations 

during a low-flow period............................................................................. 82

Figure 3-6. Peak annual flows at the Marietta and Conowingo USGS gages, 1968 

to 2012......................................................................................................... 83

Figure 3-7. Consumptive water use in the Susquehanna River Basin ........................... 84

Figure 3-8. Summary of Susquehanna River water temperature data at Harrisburg, 

Pennsylvania, 2008 to 2013 ........................................................................ 89

Figure 3-9. Summary of Susquehanna River DO data at Harrisburg, Pennsylvania, 

2008 to 2013................................................................................................ 90

Figure 3-10. Summary of Susquehanna River pH data at Harrisburg, Pennsylvania, 

2008 to 2013................................................................................................ 91

Figure 3-11. DO profiles taken immediately upstream of Conowingo dam from 

July through September 2010.................................................................... 100

Figure 3-12. Mussel sampling sites located below the York Haven Power Plant, 

Susquehanna River.................................................................................... 113
xii

Figure 3-13. Mussel sampling sites located below Conowingo dam, Susquehanna 

River.......................................................................................................... 118

Figure 3-14. Proposed location of the York Haven nature-like fishway and 

associated construction sites...................................................................... 147

Figure 3-15. View of the east end of the Conowingo powerhouse showing the 

approximate locations of Interior’s recommended entrance 

modifications to the east fish lift............................................................... 155

Figure 3-16. Maryland DNR American shad population estimates for the 

Conowingo tailrace, 1986 to 2012 ............................................................ 163

Figure 3-17. Graphical depiction of number of American shad spawners, from 

multiple sources reaching upriver spawning habitat (primarily 

upstream of York Haven), 1980 to 2014................................................... 167

Figure 3-18. York Haven Project recreation facilities................................................... 246

Figure 3-19. Muddy Run Project recreation facilities.................................................... 249

Figure 3-20. Conowingo Project recreation facilities.................................................... 252

Figure 3-21. Aesthetic (audio and visual) assessment locations.................................... 309
xiii

LIST OF TABLES

Table 1-1. Major statutory and regulatory requirements for the Susquehanna River 

Projects. ......................................................................................................... 5

Table 3-1. Hydroelectric projects on the lower Susquehanna River ............................ 72

Table 3-2. Prorated flows at York Haven Project based on monthly flow data from 

USGS gage no. 01576000 Susquehanna River at Marietta, 

Pennsylvania, for October 1, 1967, to September 30, 2009........................ 73

Table 3-3. Muddy Run Project monthly average withdrawals and discharge for 

2006 to 2010................................................................................................ 76

Table 3-4. Summary of daily and hourly Muddy Run Project discharge and 

withdrawal characteristics for 30-day high- and low-flow periods for 

2008 to 2010................................................................................................ 77

Table 3-5. Minimum flows for the Conowingo Project agreed upon in 1989 

Settlement Agreement ................................................................................. 80

Table 3-6. Monthly flow data (cfs) from USGS gage no. 01578310 Susquehanna 

River at Conowingo, Maryland, for October 1, 1967, to September 30, 

2009 ............................................................................................................. 80

Table 3-7. Consumptive use for power generation in the lower Susquehanna River .. 85

Table 3-8. Out-of-basin diversions in the lower Susquehanna River........................... 86

Table 3-9. Summary of stream classifications and water quality criteria for the 

lower Susquehanna River............................................................................ 87

Table 3-10. Summary of water quality data collected in or near the tailrace of the 

Muddy Run Pumped Storage Project, 2006 through 2011 ......................... 94

Table 3-11. Summary of water quality data collected in the Muddy Run Pumped 

Storage Project reservoir, 2010 and 2011 ................................................... 95

Table 3-12. Selected water quality parameters recorded by USGS at the Unit 8 

discharge from January 1978 to June 2000................................................. 98

Table 3-13. Summary of American shad passage on the Susquehanna River, 1997–

2014 ........................................................................................................... 105

Table 3-14. Summary of other anadromous fish (not including American shad) and 

gizzard shad passage on the Susquehanna River, 1997–2014 .................. 107
xiv

Table 3-15. Mussel species collected in the Susquehanna River, York Haven 

Project, August 2010 (Source: York Haven Power, 2012a) .................... 114

Table 3-16. Live mussels collected using semi-quantitative methods in the 

Susquehanna River, York Haven Project, August 17 to 18, 2010 ............ 115

Table 3-17. Freshwater mussels collected in the Conowingo Project area .................. 119

Table 3-18. Proposed minimum flow schedule for York Haven Project ..................... 133

Table 3-19. Summary of Exelon and TNC flow recommendations............................. 136

Table 3-20. Total number of dead fish and crabs observed during 12 stranding 

surveys (4 in each season) conducted within and just downstream of the 

spillway reach below Conowingo dam ..................................................... 140

Table 3-21. Summary of Exelon’s habitat persistence analysis by month, showing 

the range of flows (cfs) providing 70 percent of the MWUA for fish 

species and life stages likely to occur during each month, compared to 

Exelon’s current operation and median unregulated flow ........................ 144

Table 3-22. Numbers of shad lifted at Holtwood and Safe Harbor dams, and the 

effectiveness of the Safe Harbor fish lift, reported as percent of the 

Holtwood passage...................................................................................... 150

Table 3-23. American shad passage at lower Columbia River dams, and passage 

effectiveness between dams, 1984 to 2013 ............................................... 160

Table 3-24. Number of American shad spawners, from multiple sources reaching 

upriver spawning habitat (primarily upstream of York Haven), 1980 to 

2014 ........................................................................................................... 165

Table 3-25. Summary of Interior preliminary fishway prescription and Pennsylvania 

FBC recommendations for upstream anadromous fish passage at 

Conowingo dam ........................................................................................ 169

Table 3-26. York Haven Project wetland types and acreages...................................... 195

Table 3-27. Invasive plants with potential to occur in the vicinity of the 

Susquehanna River Projects...................................................................... 198

Table 3-28. State protected plant species with potential to occur in the vicinity of the 

York Haven, Muddy Run, and/or Conowingo projects ............................ 201

Table 3-29. State-protected wildlife species with potential to occur in the vicinity of 

the York Haven, Muddy Run, and/or Conowingo projects ...................... 217
xv

Table 3-30. Recreation sites at the York Haven Project............................................... 247

Table 3-31. Recreation facilities in the Muddy Run Project area................................. 250

Table 3-32. Recreation facilities in the existing Conowingo Project boundary........... 253

Table 3-33. Physical capacity utilization of York Haven Project recreation sites....... 260

Table 3-34. Physical capacity utilization of Muddy Run Project recreation sites........ 261

Table 3-35. Physical capacity utilization of Conowingo Project recreation sites........ 262

Table 3-36. Recorded archaeological and historic sites identified within the 

Susquehanna River Projects APEs............................................................ 286

Table 3-37. Historic structures identified within the Susquehanna River Projects 

APEs.......................................................................................................... 292

Table 3-38. Audio assessment results........................................................................... 311

Table 3-39. Loudness comparison chart....................................................................... 312

Table 3-40. Population in Cecil and Harford Counties, Maryland, and the state of 

Maryland ................................................................................................... 314

Table 3-41. Population in Dauphin, Lancaster, and York counties, Pennsylvania, and 

the state of Pennsylvania ........................................................................... 314

Table 3-42. Employment and unemployment percent numbers 2012.......................... 315

Table 3-43. Per capita income for Pennsylvania and Maryland counties in 2000 and 

2010, with percent change (inflation adjusted, 2010$)............................. 316

Table 4-1. Parameters for economic analysis of the York Haven Project.................. 321

Table 4-2. Parameters for economic analysis of the Muddy Run Project .................. 322

Table 4-3. Parameters for economic analysis of the Conowingo Project................... 323

Table 4-4. Summary of the annual cost of alternative power and annual project cost 

for three alternatives for the York Haven Project ..................................... 324

Table 4-5. Summary of the annual cost of alternative power and annual project cost 

for three alternatives for the Muddy Run Project...................................... 324

Table 4-6. Summary of the annual cost of alternative power and annual project cost 

for three alternatives for the Conowingo Project ...................................... 325
xvi

Table 4-7. Cost of environmental mitigation and enhancement measures considered 

in assessing the environmental effects of continuing to operate the York 

Haven Project ............................................................................................ 328

Table 4-8. Cost of environmental mitigation and enhancement measures considered 

in assessing the environmental effects of continuing to operate the 

Muddy Run Project ................................................................................... 337

Table 4-9. Cost of environmental mitigation and enhancement measures considered 

in assessing the environmental effects of constructing and operating the 

Conowingo Project.................................................................................... 344

Table 5-1. Fish and wildlife agency recommendations for the Susquehanna River 

Projects...................................................................................................... 403
xvii

ACRONYMS AND ABBREVIATIONS

ADA Americans with Disabilities Act

Advisory Council Advisory Council on Historic Preservation

APE area of potential effects

ASMFC Atlantic States Marine Fisheries Commission

BMP best management practice

CDP census-designated place

CFR Code of Federal Regulations

certification water quality certification

cfs cubic feet per second

Commission Federal Energy Regulatory Commission

Conowingo Project Conowingo Hydroelectric Project

Corps U.S. Army Corps of Engineers

CPUE catch-per-unit-effort

CZMA Coastal Zone Management Act

dbh diameter at breast height

DO dissolved oxygen

DPS distinct population segment 

EIS environmental impact statement

EPA U.S. Environmental Protection Agency

ESA Endangered Species Act

Exelon Exelon Generation Company, LLC

oF degrees Fahrenheit

FEMP Fish passage effectiveness monitoring plan

FERC Federal Energy Regulatory Commission

FPOP fish passage operating procedures

FPA Federal Power Act

FPMP fish passage monitoring plan

FWS U.S. Fish and Wildlife Service

HPMP Historic Properties Management Plan

Interior U.S. Department of the Interior

IVM Integrated Vegetation Management

kV kilovolt

LSRWA Lower Susquehanna River Watershed Assessment

Maryland DOE Maryland Department of the Environment

Maryland DNR Maryland Department of Natural Resources

mgd million gallons per day

mg/L milligrams per liter

Muddy Run Project Muddy Run Pumped Storage Project

MW megawatt

MWh megawatt-hour

MWUA maximum weighted usable area 
xviii

National Register National Register of Historic Places

NERC North American Electric Reliability Corporation

NHPA National Historic Preservation Act 

NMFS National Marine Fisheries Service

NPDES National Pollutant Discharge and Elimination System 

NTU nephelometric turbidity unit

PA Programmatic Agreement

PBAPS Peach Bottom Atomic Power Station

Pennsylvania DEP Pennsylvania Department of Environmental Protection

Pennsylvania FBC Pennsylvania Fish and Boat Commission

Pennsylvania DCNR Pennsylvania Department of Conservation and Natural 

Resources 

PPL BI PPL Brunner Island LLC 

ppt parts per thousand

RM river mile

RSP Revised Study Plan

SAV submerged aquatic vegetation

SD1 Scoping Document 1

Settling Parties York Haven Power, FWS, Pennsylvania FBC, Maryland 

DNR, and SRBC

SHPO State Historic Preservation Officer

SMP Shoreline Management Plan

SPM surplus production method 

SRAFRC Susquehanna River Anadromous Fish Restoration 

Cooperative

SRBC Susquehanna River Basin Commission

Susquehanna River Projects York Haven, Muddy Run, and Conowingo projects

TMDL Total Maximum Daily Load

USGS U.S. Geological Survey

WMA Wildlife Management Area 

York Haven Power York Haven Power Company, LLC
xix

EXECUTIVE SUMMARY

The Federal Energy Regulatory Commission (Commission or FERC) staff is 

reviewing applications to continue operating (relicense) three hydropower projects 

located on the lower Susquehanna River (the Susquehanna River Projects): the 

19.62-megawatt (MW) York Haven Hydroelectric Project (York Haven Project); the 

800.25-MW Muddy Run Pumped Storage Project (Muddy Run Project); and the 

574.54-MW Conowingo Hydroelectric Project (Conowingo Project).

Proposed Actions

On August 30, 2012, York Haven Power Company, LLC (York Haven Power)

filed an application for a new license for the existing York Haven Hydroelectric Project 

No. 1888. On January 30, 2014, York Haven Power filed an Offer of Settlement. In the 

accompanying Explanatory Statement, York Haven Power stated that the Settlement 

Agreement represents a complete resolution among the Settling Parties of all issues 

pending in the proceeding.7

 The York Haven Project is located on the Susquehanna 

River at river mile (RM) 55 in the city of York, in York, Dauphin, and Lancaster 

counties, Pennsylvania. The project does not occupy any federal lands. 

On August 29, 2012, and August 31, 2012, respectively, Exelon Generation 

Company, LLC (Exelon) filed applications for new licenses with the Commission for the 

existing Muddy Run Pumped Storage Project No. 2355 and the existing Conowingo 

Hydroelectric Project No. 405. The Muddy Run and Conowingo projects are located on 

the Susquehanna River at RM 22 and RM 10, respectively, in Lancaster and York 

counties, Pennsylvania, and Cecil and Harford counties, Maryland.8

 Conowingo Pond, 

the reservoir for the Conowingo Project, acts as the lower reservoir for the Muddy Run 

Project. The Muddy Run Project also includes an upper reservoir for pumped storage 

operation. The projects do not occupy any federal lands. 

Project Descriptions

York Haven Project 

The York Haven Project consists of a headrace wall, main dam, east channel dam, 

powerhouse, and forebay bulkhead. The main dam is attached to the north end of the 

 

7 The Settling Parties are York Haven Power, U.S. Fish and Wildlife Service, 

Pennsylvania Fish and Boat Commission, Maryland Department of Natural Resources, 

and the Susquehanna River Basin Commission. 

8 The authorized capacity for Muddy Run is from the original license issued 

September 21, 1964, and the authorized capacity for Conowingo is from the Commission 

Order issued March 3, 2010.
xx

headrace where it runs diagonally across the main channel of the river to the west shore 

of Three Mile Island. The main dam has a maximum height at the crest of 18 feet and an 

average height of 10 feet. The east channel dam extends from the east shore of Three 

Mile Island to the east bank of the river, and it has an average height of 9 feet. The stone 

masonry forebay bulkhead wall extends west from the south end of the powerhouse to the 

transformer building, perpendicular to the shoreline. From the transformer building, the 

forebay bulkhead wall extends north along the property line to the west bank of the river. 

A trash sluice gate and associated spillway are located adjacent to the southern end of the 

powerhouse at the eastern end of the forebay wall.

York Haven’s impoundment, Lake Frederic, is 3.5 miles long with 29 miles of 

total shoreline length within the project boundary, including the shoreline of the islands 

in Lake Frederic. At the normal water surface elevation of 277.86 feet, Lake Frederic has 

a surface area of 2,218 acres and 9,600 acre-feet of gross storage capacity. The 

impoundment provides approximately 22.5 feet of net head for power generation

purposes.9

The brick and stone masonry powerhouse is integral with the dam and includes 20 

turbine-generator units and appurtenant equipment. Water flowing through the turbines 

is discharged into the tailrace immediately downstream of the dam.

There are no primary transmission lines included as part of the project. The York 

Haven Project interconnects with the 115-kilovolt (kV) electric grid at the substation 

located immediately downstream of the project’s forebay wall. 

An east channel upstream fish passage facility located at the western end of east 

channel dam has been operational since April 2000. 

The project includes 10 recreation facilities that York Haven Power owns and 

operates: the Historic Canal Lock, East Shore Boat Launch, Goosehorn Island Picnic 

Area, Shelley Island Recreation Area, Goodling Island Picnic Area, Beshore Island 

Recreation Area, Battery Island Recreation Area, Cly Shore recreational lot sites, York 

Haven Power Plant Recreation Area, and Canoe Portage trail. 

The project is operated in a run-of-river mode and maintains a normal pool 

elevation of 277.86 feet under low to moderate flow conditions, less than 17,000 cubic 

feet per second (cfs). Under low-flow conditions, York Haven Power has the ability to 

draw down the impoundment by up to 1.10 feet, generally for purposes of dam 

maintenance. During periods of moderate to high flow conditions of greater than 

17,000 cfs, the project turbines cannot control water levels and the impoundment 

elevation varies above normal pool elevation depending upon river flow. Under these 

 

9 Unless otherwise noted, all elevations are referenced to National Geodetic 

Vertical Datum of 1929.
xxi

conditions, water overtops the main dam, east channel dam, and headrace walls when 

their crest elevations are exceeded. 

Muddy Run Project

The Muddy Run Project consists of four dams and two reservoirs.

The upper reservoir emergency spillway is a non-gated concrete ogee-type 

structure that is 200 feet long, 20 feet high, and has a crest elevation of 521 feet that is 

directed to a vegetated natural ravine. 

Total storage in the 900-acre Muddy Run reservoir (upper reservoir) is about

56,731 acre-feet, and the total usable storage is 33,894 acre-feet at the maximum pool 

elevation of 520 feet. The maximum pool elevation is about 411 feet above the normal 

elevation of Conowingo Pond (lower reservoir), which has a surface area of 9,000 acres 

and design storage of 310,000 acre-feet at the normal full pool elevation of 109.2 feet.

A separate pool, designated as the Recreation Lake, is located adjacent to the 

upper reservoir. The pool is used for recreation purposes and is not used for water 

storage for power production purposes. The Recreation Lake spillway is a rock-cut 

channel approximately 140 feet wide with a crest elevation of 520 feet.

The power intake facilities at the west end of the upper reservoir consist of four 

cylinder gates with trashracks in a cylindrical tower, and each intake supplies two units. 

Each intake leads to a horizontal power tunnel, which divides into two sections. The 

power tunnel sections transition to a penstock that leads to one of the eight reversible 

pump-turbine units in the powerhouse. The powerhouse is located along the shore of the 

Susquehanna River. The powerhouse houses eight Francis turbines each equipped with a 

100-MW generator. The turbines have a total discharge capacity from the powerhouse of 

32,000 cfs. The total powerhouse pumping capability is 28,000 cfs. Water flowing 

through the turbines is discharged via the draft tubes into the Susquehanna River adjacent 

to the powerhouse. The units are equipped with trashracks between the draft tube outlet 

and the river. Electricity generated at the project is transmitted by two individual 220-kV 

transmission lines extending from the project switching station approximately 4.25 miles 

to the Peach Bottom Atomic Power Station North Substation located in York County.

The project also includes three recreation areas: Muddy Run Park, owned by 

Exelon and operated by a vendor; Wissler’s Run Park, owned and operated by Exelon; 

and Muddy Run Wildlife Management Area, owned by Exelon and leased to and 

managed by the Pennsylvania Game Commission. 

The Muddy Run Project is a pumped storage hydroelectric facility. Water is 

pumped at night (typically) from the lower reservoir (Conowingo Pond) to the upper 

reservoir that has 33,894 acre-feet of active storage available for pumped storage 

operation. Water is then released from the upper reservoir through the powerhouse units 

to the Susquehanna River (Conowingo Pond). Typically, pumping occurs during lowload periods when energy costs are low (nights and weekends), while generation occurs 

during high-load periods.
xxii

Conowingo Project

The existing Conowingo Project consists of a concrete gravity dam with a nonoverflow gravity section, an ogee-shaped spillway section, an intake-powerhouse section, 

and a 127-foot-long abutment section. The spillway consists of a 2,250-foot-long section 

with a crest elevation of 86.0 feet, and a 135-foot-long section with a crest elevation of 

99.2 feet. The spillway is fitted with 50 Stoney-type crest gates and two regulating gates. 

Each Stoney crest gate is 22.5 feet high by 38 feet wide and has a discharge capacity of 

16,000 cfs at a reservoir elevation of 109.2 feet. The two regulating gates are 10 feet 

high by 38 feet wide and have a discharge capacity of 4,000 cfs per gate at a reservoir 

elevation of 109.2 feet. The dam includes two fish lifts: a west fish lift and a newer 

east fish lift.

Conowingo dam impounds the Conowingo reservoir (Conowingo Pond) which

extends 14 miles upstream from the dam. Total storage in the 8,500-acre reservoir is 

approximately 310,000 acre-feet at the normal full pool elevation of 109.2 feet. The 

elevation of the normal river surface below the dam is approximately 20.5 feet. The 

impoundment provides approximately 89 feet of gross head for power 

generation purposes.

The powerhouse is integral with the dam and is composed of 13 turbine-generator 

units, draft tubes, and transformer bays. Water flowing through the turbines is discharged 

via the draft tubes into the tailrace immediately downstream of the dam. There are no 

primary transmission lines associated with the project. 

The project also includes 15 recreation facilities and public access areas owned by 

Exelon: Lock 13, Lock 15, Muddy Creek Boat Launch, Cold Cabin Boat Launch, Dorsey 

Park, Line Bridge, Broad Creek Public Landing, Glen Cove Marina, Conowingo 

Swimming Pool and Visitor’s Center, Peach Bottom Marina, Conowingo Creek Boat 

Launch, Funk’s Pond, Conowingo Dam Overlook, Fisherman’s Park/Shures Landing,

and Octoraro Creek Access. Exelon operates seven of these facilities and leases the other 

eight to local and state entities or commercial operators. 

The Conowingo Project is a peaking hydroelectric facility that uses reservoir storage 

to generate during peak electricity demand periods. The current Conowingo Project license 

allows for Conowingo Pond to fluctuate daily between elevation 101.2 and 110.2 feet.
xxiii

Proposed Facilities

York Haven Project

York Haven Power proposes to construct a nature-like fishway10 at the north end 

of the main dam where it abuts Three Mile Island. The installation would require 

modifications to the north end of the dam. No other major modifications are proposed to 

project facilities.

Muddy Run Project

Exelon is not proposing any major modifications to the Muddy Run Project; 

however, it proposes minor improvements at the project’s recreation facilities.

Conowingo Project

Exelon proposes to construct an eel trapping facility on the western shore of the 

Susquehanna River downstream of Conowingo dam and a temporary eel trapping facility 

on Octoraro Creek which enters the Susquehanna River approximately 4,500 feet 

downstream of Conowingo dam on the east shore. If the temporary facility is successful 

after 3 years, then Exelon would construct a permanent eel trapping facility on Octoraro 

Creek. No other major modifications to project facilities are proposed at the Conowingo 

Project; however, minor improvements are proposed for the project’s recreation facilities.

Proposed Environmental Measures 

York Haven Project

Under the terms of the Settlement Agreement, York Haven Power proposes the 

following environmental measures at the York Haven Project:

• Develop an erosion and sediment control plan for construction of the 

nature-like fishway.

• Continue to operate and maintain the existing east channel upstream 

fishway for upstream fish passage.

• Continue the current downstream juvenile American shad passage protocol

that calls for the operation of units 1-6 (Kaplan and propeller units) to be 

first online and last offline during the juvenile shad downstream migration 

period (which typically is from October 1 through November 30), and 

opening the forebay sluice gate at specific times for downstream fish 

passage. If river flows exceed the capacity of units 1-6, unit 14 would be 

 

10 A nature-like fishway is a fishway that is designed to appear and operate similar 

to a natural riffle, with a gradually sloping channel interspersed with rock weirs and 

pools. These fishways are typically suitable for a wide range of species. 
xxiv

operated, and if flows exceed the capacities of units 1-6 and 14, units 7-13 

and 15-30 would be operated in ascending order.

• Provide a year-round, continuous, minimum flow from the project of 

1,000 cfs and an average daily minimum flow of 2,500 cfs, or inflow, 

whichever is less, to protect and enhance aquatic resources downstream of 

the project. 

• Continue to operate the project in a run-of-river mode when inflow to the 

project is less than 3,000 cfs. 

• Pass about 370 cfs through the forebay sluice gate for 1 or 2 hours in the 

morning during weekdays if river flows exceed the sum of the turbine 

hydraulic capacity, flows through the nature-like fishway, once constructed, 

flows through the east channel, and flows (if any) over the main dam from 

May 1 through June 30 to facilitate downstream passage of post-spawning 

adult American shad, and any day that river flow exceeds the combined 

hydraulic capacity during the fall American shad emigration period to 

facilitate downstream passage of juvenile American shad. 

• Pass about 370 cfs through the forebay sluice gate between the hours of 

5 p.m. and 11 p.m. during the entire fall juvenile American shad passage 

period to facilitate downstream passage of juvenile American shad.

• Develop designs within 4 years of license issuance for: (1) removal of 

obstructions in or deepening of the downstream plunge pool for the forebay 

sluice gate, and (2) a chute structure to convey flows beyond the roadway 

on the downstream side of the cable alley structure to protect outmigrating 

juvenile and adult American shad passing into the downstream plunge pool.

• Cooperate with resource agencies and other interested parties to conduct a 

lower Susquehanna River downstream eel migration study including 

monitoring silver eels at the project and providing $25,000 to support 

the study.

• Conduct a site-specific silver eel route of passage study and a survival 

study as described in appendices G and H of the Settlement Agreement 

including the potential for providing $50,000 to resource agencies for 

collection and tagging of silver eels at upstream locations.

• Conduct a downstream eel passage improvement study if downstream eel 

passage goals are not achieved with provisions for subsequent monitoring 

and adjustments. 
xxv

• Prior to construction of the proposed nature-like fishway:

o Provide a minimum flow of 2,000 cfs at east channel dam and a 

spillage flow of 4,000 cfs at the main dam during the American shad 

upstream passage season when the east channel fishway is in 

operation.

o After the American shad upstream passage season until the end of 

the resident fish passage season maintain a minimum flow of 400 cfs 

in the east channel downstream from the east channel fishway during 

the period that the east channel fishway is operated to allow 

upstream passage of resident fish species, per the June 2010 Consent 

Order and Agreement between York Haven Power and Pennsylvania 

Department of Environmental Protection (Pennsylvania DEP). 

o Conduct vegetation surveys, wetlands delineations, invasive species 

surveys, rare species surveys, bog turtle habitat assessments, and 

bald eagle surveys in the area of the nature-like fishway.

11 

• After construction of the nature-like fishway:

o Conduct American shad upstream passage effectiveness studies 

using radio telemetry beginning during the second year of the 

nature-like fishway operation. If the project area passage success 

criterion is not achieved, York Haven Power would implement 

corrective measures, followed by two additional years of radio 

telemetry studies to confirm achievement of the project area passage 

success criterion.

o Conduct a juvenile American shad headrace turbine avoidance study 

consistent with design criteria included in appendix D of the 

Settlement Agreement.

o If the juvenile American shad headrace turbine avoidance goals are 

not achieved, implement measures that would enhance the 

effectiveness of downstream passage and conduct a supplemental 

juvenile American shad headrace turbine avoidance study within 2 

years of implementing the measures. 

 

11 These proposed measures cited in the explanatory statement accompanying the 

Offer of Settlement would be implemented prior to the construction of the nature-like 

fishway. 
xxvi

o Provide an average daily minimum flow in the east channel below 

east channel dam of 267 cfs year round to protect aquatic resources 

in the east channel and provide a minimum passage flow for fish 

ascending the east channel and using the east channel fishway.

o Provide a minimum of 5 percent of the river flow through the 

nature-like fishway during the American shad upstream passage 

season such that when inflows to the project are between 5,000 and 

150,000 cfs, total flow through the nature-like fishway would range 

from about 1,000 to 7,500 cfs, depending on inflow. 

o Provide a minimum flow of 200 cfs through the nature-like fishway 

outside of the American shad upstream passage season when the 

river elevation is at the crest of the main dam. 

o When flows exceed the hydraulic capacity of all available generating 

units, and to the extent controllable by York Haven Power, manage 

flows to maximize flow over the main dam and the nature-like 

fishway to provide attraction flow to the vicinity of and from the 

nature-like fishway to maximize fishway effectiveness.

• To prevent a buildup of debris that could affect project and fish passage 

operations, remove non-natural debris from the forebay and sluice 

remaining natural debris downstream, after notifying the downstream PPL 

Brunner Island Station. 

• Contribute $25,000 per year to the York Haven Conservation District or 

such other entity identified by the Pennsylvania DEP for the purposes of 

debris removal in the lower Susquehanna River watershed.

In addition to the measures specified in the Settlement Agreement, York Haven 

Power also proposes to implement the following measures.

• Maintain existing project recreation facilities on four islands in Lake 

Frederic and the project recreation facilities at the powerhouse, including an 

existing portage trail for canoeists and fishing access along the downstream 

face of the powerhouse, and consult with the resource agencies on 

recreation resources and management strategies every 10 years after the 

effective date of any new license. 

• Continue the current permitting program for the approximately 300 

recreational lots located within the project boundary, but terminate permits 

and remove lots from the program if structures are abandoned by the lessee, 

or when existing structures become damaged and are not replaced by 

conforming structures. 
xxvii

• Implement the Historic Properties Management Plan (HPMP) filed with the 

Commission on December 28, 2012, to manage project effects on

properties eligible for listing on the National Register of Historic Places

(National Register). 

Muddy Run Project 

Exelon proposes the following environmental measures at the Muddy Run Project:

• Develop a dissolved oxygen (DO) monitoring plan no earlier than 

November 1, 2027, with measures designed to ensure that the project does 

not violate DO standards.

• Develop fish passage operating procedures (FPOP) for minimizing delay 

and potential fish entrainment during upstream and downstream 

fish passage past the project tailrace during generating and pumping cycles.

• Develop a plan and schedule for a radio telemetry study or equivalent 

Tier II study of American shad passage and behavior within the Muddy 

Run Project boundary if resource agencies determine that operation of the 

Muddy Run Project is causing the Holtwood Project to fail to meet the Tier 

I upstream American shad target specified in the water quality certification 

for the Holtwood Project.

• Develop a downstream eel passage plan to ensure safe and timely passage 

past the Muddy Run Project.

• Implement the American Eel Passage Plan12 filed with the license 

application for an eel trap and truck program to trap, hold, and transport 

American eels from the Conowingo Project and Octoraro Creek to 

designated points in the Susquehanna River watershed until at least 2030, 

and then either continue the trap and truck program or construct a volitional 

eel passage facility at Conowingo dam. 

• Implement the Bald Eagle Management Plan filed with the license

application to minimize impacts to bald eagles and their habitat within the 

project boundary in accordance with recommendations from the National 

Bald Eagle Management Guidelines (FWS, 2007a) and state agency 

guidance. 

 

12 Exelon filed an Eel Management Plan with its final license application. In the

water quality certification for the Muddy Run Project, the Pennsylvania Department of 

Environmental Protection called this plan an American Eel Passage Plan, and we use this 

title throughout the EIS. 
xxviii

• Implement the Bog Turtle Management Plan filed with the license 

application to minimize impacts to bog turtles and that includes: 

(1) the restriction of mowing in the wetland documented to support bog 

turtles; (2) invasive plant and woody plant control, particularly for reed 

canary grass; and (3) limits on public access to the wetland without 

advertising the reason.

• Once every 10 years through the term of the license, evaluate all state and 

federal endangered and threatened species that may be present within the 

project boundary, and if the evaluation identifies the presence, critical 

habitat, or critical dependence of endangered species, propose and 

implement a protection plan for each species.

• Provide annual grants of up to $450,000 each to the Lancaster County and 

York County Conservation Districts for the implementation of agricultural 

pasture and barnyard best management practices (BMPs) to control 

sediment loading into the Susquehanna River.

• Provide $50,000 annually to the Pennsylvania Fish and Boat Commission 

(Pennsylvania FBC) for habitat improvement projects, including removal of 

small dams. 

• Implement the Recreation Management Plan filed with the license 

application that includes the following improvements to project recreation 

facilities: an improved launching ramp and Americans with Disabilities 

Act (ADA)-compliant dock; shoreline erosion measures; an improved 

retaining wall; electric upgrades; expanded playground area near the 

Visitor’s Center; and construction of a 2,000-square-foot water spray park 

near the park entrance, along with paving resurfacing (see section 2.2,

Applicants’ Proposals, for a full description of proposed capital 

improvements at each site). 

• Implement the Shoreline Management Plan (SMP) filed with the license 

application that includes measures and policies related to shoreline 

vegetation management and erosion control, woody debris management, 

game species management, sensitive natural resource protection, recreation 

use, and use of project lands and BMPs for controlling sediment 

introduction. 

• Implement the osprey management policy described in Exelon’s 

proposed SMP.

• Prepare a cultural resources management plan if cultural materials are 

identified during project-related activities. 
xxix

Conowingo Project

Exelon proposes to continue the following environmental measures:

• Operate the project with a normal daily range of operation of Conowingo 

Pond between elevations 101.2 and 110.2 feet, with a minimum elevation 

of 107.2 feet on weekends between Memorial Day and Labor Day, to meet 

recreational needs.

• Provide minimum downstream flow releases from the project as follows:

- March 1 – March 31: 3,500 cfs or natural inflow,

13 whichever is less;

- April 1 – April 30: 10,000 cfs or natural inflow, whichever is less;

- May 1 – May 31: 7,500 cfs or natural inflow, whichever is less;

- June 1 – September 14: 5,000 cfs or natural inflow, whichever is less;

- September 15 – November 30: 3,500 cfs or natural inflow, whichever is 

less; and

- December 1 – February 28: 3,500 cfs intermittent (maximum six hours 

off followed by equal amount on).

• Enhance DO at the project using the turbine venting systems on Units 1 

through 7 and the aerating runners on Units 2 and 5, and continuously 

monitor DO levels from May 1 through October 1 at the Station 643 

location about 0.6 mile downstream of Conowingo dam.

• Operate the east fish lift to pass American shad, river herring, and other 

migratory fishes, and the west fish lift for American shad egg collection 

and other research purposes.

• Manage debris to include clamming (with three gantry cranes with grapple 

attachments) to remove submerged debris from the area upstream of the 

powerhouse intakes and floating surficial debris in front of the powerhouse 

intakes, and sponsoring community-based clean-ups in the pond and 

downstream of the dam. 

• Maintain the project’s public recreation facilities.

Exelon proposes the following new environmental measures: 

• Implement the Sediment Management Plan filed with the license 

application that identifies benchmarks and thresholds for actions to address 

sediment issues that may affect project operation. 

 

13 As measured at the upstream U.S. Geological Survey (USGS) Marietta gage 

(No. 01576000).
xxx

• Conduct a bathymetric survey of Conowingo Pond every 5 years to monitor 

sediment transport and depositional patterns within the pond.

• Implement a preventive maintenance program for the east fish lift to extend 

the useful life of the facility over the next license term.

• Use the project turbines as the route for downstream passage of American 

shad and river herring.

• Construct a permanent trap and transport facility for the upstream passage 

of American eel, consisting of an eel ramp and collection facility on the 

west and east banks of the Conowingo tailrace (an alternative east bank 

facility would be in Octoraro Creek).

• After 2030, construct volitional eel passage facilities on the west and east 

banks that consist of full eel ramps with resting pools. 

• Participate in a trap and transport program for downstream eel passage, in 

cooperation with the other hydroelectric project operators on the lower 

Susquehanna River to trap and transport adult American eels from smaller 

tributaries upstream of York Haven dam to below Conowingo dam.

• Implement the Bald Eagle Management Plan filed with the license 

application to minimize impacts to bald eagles and their habitat within the 

project boundary in accordance with recommendations from the National 

Bald Eagle Management Guidelines (FWS, 2007a) and state agency 

guidance. 

• Implement the Recreation Management Plan filed with the application that 

provides for improvements to 13 project recreation facilities, including 

directional signage to facilities and canoe portages, expanded parking, 

ADA-compliant and boat trailer parking spaces, fencing, shoreline 

stabilization, new or repaired boat ramps, improved access, picnic tables, 

portable restrooms, and other amenities. 

• Implement the SMP filed with the license application that includes

measures and policies related to shoreline vegetation management and 

erosion control, woody debris management, game species management, 

sensitive natural resource protection, recreation use, BMPs for controlling 

sediment introduction from lands within the project boundary, and use of 

project lands. 

• Implement the osprey management policy described in Exelon’s proposed 

SMP.

• Implement the HPMP filed with the license application for the management 

of archaeological and historic resources, including: (1) a schedule and 

methodology for completing any additional recommended studies and 
xxxi

implementing monitoring measures; (2) management measures for 

identified historic properties including Conowingo dam and powerhouse; 

(3) protection of any historic properties threatened by project-related 

activities, including project operation, shoreline and aquatic recreation, 

shoreline development, routine project maintenance, and other project 

activities or operations; and (4) public outreach, education, and signage for 

the purpose of reducing looting and vandalism of sites.

Project Boundary Revisions

York Haven Project

York Haven Power proposes to add 1.9 acres to the total York Haven Project 

boundary acreage to encompass the project’s East Shore Boat Launch and Canal Lock 

recreation area. 

Conowingo Project

Exelon proposes to modify the Conowingo Project boundary by removing lands 

that are not necessary for operation and maintenance of the project or for public 

recreation or protection of environmental resources. These lands include: 0.06 acre of 

land not owned by Exelon in the upper reaches of Conowingo Pond; 34.4 acres along the 

Susquehanna River shoreline at the Muddy Run Project (to minimize the overlap of 

project lands between the two projects); and lands from upper Broad Creek and from the 

Susquehanna River downstream of Rowland Island that were originally included for 

construction of the project, including 205.6 acres on upper Broad Creek, a tributary to 

Conowingo Pond; and 1,758.7 acres of the Susquehanna River and shoreline downstream 

of Conowingo dam. The proposed project boundary would contain 9,919 acres, 

including 8,850 acres of project waters and 1,069 acres of land above the normal high 

water elevation in Lancaster and York counties, Pennsylvania, and Harford and Cecil 

counties, Maryland. Exelon would negotiate leases with existing recreation facility 

operators for the continued operation of those facilities located on lands owned by 

Exelon, but no longer within the project boundary. Exelon would also negotiate a new 

lease with Maryland Department of Natural Resources (Maryland DNR) for the 

continued protection and use of the collocated Lower Susquehanna Greenway Trail and 

Mason-Dixon Trail on Exelon-owned lands outside of the project boundary. The existing 

lease expires in August 2014.

Alternatives Considered

In addition to the applicants’ proposals, as outlined above, this draft environmental 

impact statement considers the following alternatives: (1) the applicants’ proposals with 

staff-recommended modifications (staff alternative), and (2) a no-action alternative.
xxxii

Staff Alternative

Under the staff alternative, the projects would be operated as proposed by York 

Haven Power and Exelon with the modifications and additional staff-recommended 

measures described below for each project: 

York Haven Project

• Develop a recreation management plan that provides for York Haven’s 

proposed maintenance of its existing recreation facilities with additional 

provisions to update the plan every 12 years consistent with every other 

Form 80 reporting period deadline, include safety measures during 

construction of the nature-like fishway, continue the licensing program for 

approximately 300 recreational lots within the project boundary, and 

implement revisions to the program to allow for the termination of permits 

and removal of lots from the program if structures are abandoned by the 

lessee, or when existing structures become damaged and are not replaced 

by conforming structures.

• Develop an SMP that includes specific measures and policies related to 

shoreline management at the project and include a provision to update the 

plan every 10 years. 

• Modify York Haven’s proposed HPMP with the following additional 

provisions: (a) include a requirement to request landowner permission to 

access sites on private lands within the project boundary and evaluate them 

for listing on the National Register and for project impacts if project 

impacts are identified during monitoring activities; (b) a plan and schedule 

to evaluate archaeological sites on York Haven lands within the project 

boundary for their National Register eligibility to ensure that any effects to 

sites owned by York Haven Power are fully considered in accordance with 

section 106; and (c) include two additional sites (36YO300, 36YO334) in 

the monitoring schedule, or clarification regarding why they were excluded.

Muddy Run Project

• Visit the U.S. Fish and Wildlife Service’s (FWS) Chesapeake Bay Field 

Office and the Pennsylvania Field Office websites prior to any ground 

disturbance, and follow the bog turtle and bald eagle guidelines. 

• Modify Exelon’s proposed Recreation Management Plan to include 

recreation use monitoring and plan updates every 12 years in concert with

every other Form 80 reporting deadline.

• Modify Exelon’s proposed SMP to include a provision to update the plan 

every 10 years. 
xxxiii

• Develop an HPMP that provides for the management of historic properties 

and unevaluated cultural resources within the project’s area of potential

effects (APE) and includes: (a) a detailed discussion of the three sites

(36LA67, 36LA103, 36LA368) identified during Phase IA cultural 

resources surveys and two additional sites (36LA70, 36LA47) located 

outside of the project boundary but within the area of potential affect; 

(b) requirements for National Register evaluation of affected sites in 

consultation with the Pennsylvania State Historic Preservation Officer

(SHPO); (c) requirements for formal National Register evaluation of the 

Muddy Run Project; and (d) documentation of consultation with Indian 

Tribes. 

Although required by the water quality certification issued by Pennsylvania DEP 

for the project, the staff alternative does not include Exelon’s proposals to implement the 

American Eel Passage Plan for an eel trap and truck program and provide annual grants 

to the York County and Lancaster County conservation districts and the Pennsylvania 

FBC. The American Eel Passage Plan addresses measures to be implemented at the 

Conowingo Project, and the Commission cannot require a condition in the Muddy Run 

license that would need to be implemented through the Conowingo license. For the 

annual grants, the certification does not specify nor describe what the compensation is 

mitigating, nor do the requirements appear to be related to any specific project impact. In 

addition, providing funds is inconsistent with the Commission’s guidelines on 

environmental measures.

14 Finally, the staff alternative does not recommend Exelon’s 

proposal to evaluate all state and federal endangered or threatened species that may be 

present within the project boundary once every 10 years through the term of the license. 

The Commission typically includes in its licenses a standard license article with a fish 

and wildlife reopener provision that could be used to require changes to project facilities 

upon Commission motion or as recommended by the appropriate federal and state fish 

and wildlife agencies after notice and opportunity for hearing. This standard reopener 

provision retains authority for the Commission to implement any measures that may be 

needed to protect threatened or endangered species or other fish and wildlife resources 

over the term of any license issued for the project.

Conowingo Project 

• Modify Exelon’s proposed Sediment Management Plan to include periodic 

dredging at the Conowingo Creek, Peters Creek (Peach Bottom Marina), 

and Broad Creek boat ramps, where sediments have been accumulating, to 

improve and maintain recreational boating access; and include with the 

 

14 See Policy Statement on Hydropower Licensing Settlements, issued 

September 21, 2006.
xxxiv

results of each bathymetric survey an analysis of any change in sediment 

deposition or scour in the pond from the previous survey(s). 

• Modify Exelon’s proposed minimum flow regime to enhance minimum 

flows from December through February, by eliminating periods with no 

minimum flow, and by increasing the minimum flow during the first 2 

weeks of June, summarized as follows: 

− September 15 – March 31: 3,500 cfs or natural inflow (as measured at 

the U.S. Geological Survey Marietta gage No. 0157600), whichever is 

less;

− April 1 – April 30: 10,000 cfs or natural inflow, whichever is less;

− May 1 – June 15: 7,500 cfs or natural flow, whichever is less;

− June 16 – September 14: 5,000 cfs or natural inflow, whichever is less. 

• Implement measures designed to improve upstream fish passage through 

modification to the existing west and east fish lifts, including: (a) replacing 

the existing hopper at the west fish lift with a 1,500 gallon hopper; 

(b) improving the west fish lift sorting and loading process to facilitate trap 

and truck operations and implement a trap and truck program for American 

shad; (c) conducting a feasibility study for adding attraction flow at the 

west fish lift and if feasible and beneficial, install additional flow capacity; 

(d) restoring the original design for the 900-cfs attraction flow in the east 

fish lift; (e) adding a second 3,300-gallon hopper to the east fish lift in the 

space provided for in the original design, and upgrading the electrical and 

mechanical equipment to allow for a 15 minute lift cycle; and (f) if 2 years 

of effectiveness studies, after restoration of the 900-cfs attraction flow, 

show poor attraction at the east fish lift, conducting a feasibility study for 

modifying the locations of entrances A and B, and implement if feasible 

• Modify Exelon’s proposed Bald Eagle Management Plan to include 

measures to minimize recreation-related disturbance in proximity to 

roosting or foraging eagles.

• Develop a northern map turtle protection plan to minimize project impacts 

to map turtles through monitoring, habitat management, and nest site 

protection.

• Develop a waterfowl nesting protection plan to identify waterfowl nesting 

habitat that is routinely flooded during the breeding season, and where 

feasible, establish mitigation measures to minimize impacts to waterfowl 

nests.
xxxv

• Modify Exelon’s proposed Recreation Management Plan to include 

recreation use monitoring and plan updates every 12 years in concert with 

every other the Form 80 reporting deadline and a plan to provide angler 

access to the catwalk on a limited basis with security measures in place that 

address the vulnerability of the facility and the safety of the users of the 

catwalk. 

• Modify Exelon’s proposed SMP with the addition of a provision to update 

the plan every 10 years.

• Modify Exelon’s proposed HPMP to include the following additional 

provisions: (a) a revised APE with the narrow strip of land in the current 

project boundary extending downstream from Spencer Island along the 

west side of the river to Havre de Grace, Maryland; (b) a discussion of all 

48 sites and 27 historic structures identified to date within the project APE 

or an explanation of why they are not considered; (c) correction to identify 

the Susquehanna and Tidewater Canal and Columbia & Port Deposit 

Railroad eligible for listing; (d) requirements to inventory any lands within 

the revised APE, evaluate identified cultural resources for eligibility, and 

address potential effects before sale or transfer of those lands; (e) a 

requirement to make good faith effort to obtain access to private property to 

conduct studies if project effects on cultural resources on private lands are 

identified; (f) a revised list of project activities involving the Conowingo 

Project that can be completed without Maryland SHPO review; (g) a 

process for assessing project-related ground-disturbing activities to 

determine whether or not archaeological sites would be affected, 

particularly in areas that have not had archaeological surveys; 

(h) requirements to ensure confidentiality of cultural resources location 

information during implementation of public outreach programs; and (i) a 

description of project-related activities that would require consultation with 

the Delaware Nation and the Onondaga Nation in accordance with 

section 106 of the National Historic Preservation Act and documentation of 

Native American consultation. 

The staff alternative does not include the U.S. Department of the Interior’s 

(Interior’s) recommended bog turtle protection plan. Interior did not provide evidence 

that bog turtles are present within the Conowingo Project boundary, or that bog turtles are 

potentially affected by project operation or maintenance.

No Action Alternative

Under the no-action alternative, each project would continue to operate under the 

terms and conditions of the existing licenses, and no new environmental protection, 

mitigation, or enhancement measures would be implemented. 
xxxvi

Public Involvement and Areas of Concern

Before filing the license applications for the Susquehanna River Projects, York 

Haven Power and Exelon conducted pre-filing consultation under the integrated licensing 

process. The intent of the Commission’s pre-filing process is to initiate public 

involvement early in the project planning process and to encourage citizens, government 

entities, Indian tribes, and other interested entities to identify and resolve issues prior to a 

license application being formally filed with the Commission. During pre-filing, 

Commission staff conducted scoping to determine what issues and alternatives should be 

addressed. Scoping documents (SD1s) were distributed to interested agencies and others 

on July 24, 2009, for the York Haven Project, and on May 11, 2009, for the Muddy Run 

and Conowingo projects. In addition, scoping meetings were held on August 26 and 27, 

2009, for the York Haven Project; June 10, 2009, for the Muddy Run Project; and June 

11 and 12, 2009, for the Conowingo Project to request comments on the projects. 

Revised scoping documents, addressing the comments received, were issued on 

November 13, 2009, for the York Haven Project, and on August 24, 2009, for the Muddy 

Run and Conowingo projects. 

The primary issues associated with relicensing the projects are sedimentation 

effects on aquatic resources downstream of Conowingo dam, including Chesapeake Bay;

instream flows downstream of Conowingo dam; the effects of project operations on water 

quality; effective fish passage for American shad, American eel, and other diadromous 

species; protection of sensitive plant and wildlife species including the bald eagle, osprey, 

bog turtle, and northern map turtle; and enhancements to recreation opportunities and 

facilities.

Staff Alternative

Geology and Soils – Continued run-of-river operation of the York Haven Project 

would have minimal effect on shoreline erosion in Lake Frederic. Development of the 

proposed erosion and sediment control plan prior to ground-disturbing activities 

associated with construction of the nature-like fishway would ensure BMPs are in place 

to minimize erosion and sedimentation. 

Shoreline erosion effects from the operation of the Muddy Run and Conowingo 

Projects are also considered minimal, and the implementing erosion control measures 

proposed by Exelon in the SMPs would help minimize adverse effects on water quality in 

the respective reservoirs. 

Exelon’s proposed Conowingo Sediment Management Plan would identify action 

benchmarks and thresholds at the powerhouse intakes to address sedimentation-related 

issues as they might affect project operation. Exelon’s proposed bathymetric surveys in 

Conowingo Pond at 5-year intervals would allow for verification of predictions from the 

anticipated U.S. Army Corps of Engineers’ study and identify appropriate management 

actions. A final Sediment Management Plan that includes detailed benchmarks for 
xxxvii

dredging, a schedule, and commitment to dredging three boating access areas affected by 

sedimentation in Conowingo Pond as soon as the benchmark sediment depths are reached 

would protect recreation access. 

Aquatic Resources – Continued operation of the York Haven, Muddy Run, and 

Conowingo projects would have minimal effects on water quality in the lower 

Susquehanna River, and Exelon’s continued DO monitoring at the Muddy Run and 

Conowingo projects would ensure that state standards are maintained at those projects. 

Establishing a modified minimum flow regime at Conowingo that would enhance 

Exelon’s minimum flows from December through February and in the first 2 weeks of 

June would allow continued operation of the Muddy Run and Conowingo projects while 

improving downstream aquatic habitat. 

Constructing and operating the nature-like fishway at York Haven, improving the 

fish lifts at the Conowingo Project, and implementing American eel passage measures at 

the three projects would enhance upstream fish migration and maintain required 

downstream survival of diadromous fish species in the lower Susquehanna River. 

Interior filed preliminary fishway prescriptions for the York Haven, Muddy Run, 

and Conowingo projects. At York Haven, the prescription is consistent with the 

Settlement Agreement, requiring nature-like fishway and downstream passage measures. 

At Muddy Run, the prescription requires FPOP for minimizing delay and potential fish 

entrainment, and an upstream eel passage program from the downstream Conowingo 

Project. At Conowingo, the Interior prescription requires major renovations to the 

existing east and west fish lifts, and implementation of upstream eel passage at the 

project. The staff is in agreement with Interior’s fishway prescriptions for York Haven 

and Muddy Run, but notes that the Muddy Run requirements for eel passage cannot be 

enforced via another project’s license (Conowingo). In addition, while the final fishway 

prescriptions would become a requirement of any licenses issued, staff recommends an 

alternative at Conowingo that would provide substantial improvements to the fish 

passage facilities at the project and would involve renovations to the existing east and 

west fish lifts, but at a lower cost and more appropriate scale considering the current size 

of the American shad run. 

Terrestrial Resources – Raptors, including state sensitive species such as bald 

eagle and osprey, and waterfowl occur on the projects’ lands and waters, and these 

species could be affected by project operation, maintenance activities, and use of project 

recreation facilities. Implementing Exelon’s Bald Eagle Management Plan, as proposed 

for the Muddy Run Project, and with the staff modifications for the plan at the 

Conowingo Project to include measures to minimize recreation-related disturbance in 

proximity to roosting or foraging eagles, would ensure that bald eagle nesting, roosting, 

and foraging areas are protected within the Muddy Run and Conowingo project 

boundaries. 
xxxviii

Exelon’s proposed osprey management policies at the Muddy Run and Conowingo 

projects would benefit ospreys by implementing BMPs and protection measures to 

minimize effects on osprey nesting within the project boundary. 

A waterfowl nesting protection plan at the Conowingo Project, as recommended 

by Interior would identify waterfowl nesting habitat that is routinely flooded during the 

breeding season, and where feasible, establish mitigation measures to minimize impacts 

to waterfowl nests. 

A northern map turtle protection plan would minimize project impacts to map 

turtles, through monitoring, habitat management, and nest site protection, as described in 

Towson University’s 2014 final map turtle report. 

Threatened and Endangered Species – Six federally listed species are known to 

occur in the general vicinity of one or more of the projects: shortnose sturgeon 

(Acipenser brevirostrum), Atlantic sturgeon (Acipenser oxyrinchus oxyrinchus), bog 

turtle (Glyptemys [Clemmys] muhlenbergii), Indiana bat (Myotis sodalis), Delmarva 

Peninsula fox squirrel (Sciurus niger cinereus), and swamp pink (Helonias bullata). 

The York Haven and Muddy Run projects would have no effect on the shortnose 

and Atlantic sturgeons because neither species has been collected or passed via the 

Conowingo fish lifts since they began operation in 1972. While there is suitable habitat 

downstream of Conowingo for both species, there is no evidence of their occurrence in 

the lower Susquehanna River. Therefore, continued operation of the York Haven, 

Muddy Run, and Conowingo projects would not likely adversely affect the shortnose and 

Atlantic sturgeon.

Bog turtles have been confirmed near the Muddy Run Project. Implementing 

Exelon’s Bog Turtle Management Plan for the Muddy Run Project, including habitat 

management at any confirmed breeding locations and other practices to protect the 

existing population and improve bog turtle habitat would minimize effects on bog turtles 

and their habitat due to project maintenance or recreation. Therefore, we conclude that 

relicensing the Muddy Run Project may affect, but would not be likely to adversely affect 

the bog turtle. 

For the Conowingo Project, although Interior states that bog turtles have been 

observed close to Conowingo dam and recommends a bog turtle management plan, it has 

yet to provide evidence to indicate that bog turtles are present within the Conowingo 

Project boundary, and Exelon states that there is no evidence of bog turtles in the project 

area. Thus, staff cannot presently determine if bog turtles would be affected by the 

Conowingo Project. Further consultation with Interior is necessary to determine the 

potential for project effects and the need for Interior’s recommended bog turtle 

management plan.

Potential Indiana bat habitat may exist within the three project areas, along the 

riparian forested edges of the river and reservoirs, and forested edges along transmission 

line rights-of-way and recreational areas. Neither York Haven Power nor Exelon propose 
xxxix

any activities that would result in more than a minimal amount of tree clearing. At the 

Muddy Run Project, continued routine vegetation management practices, such as 

trimming and herbicide application, would be unlikely to affect trees large enough to 

provide roosting habitat. Therefore, the York Haven, Muddy Run, and Conowingo 

projects would not be likely to adversely affect the Indiana bat.

Swamp pink have been previously documented in Cecil and Harford counties 

where the Conowingo Project is located but are not known to occur in those project areas 

according to FWS’ Information, Planning, and Conservation System website. Therefore, 

the York Haven and Muddy Run projects would have no effect on the swamp pink.

The three projects would have no effect on the Delmarva Peninsula fox squirrel. 

Although it was noted in SD1 as occurring in the vicinity of the Muddy Run and 

Conowingo projects, it is not known to exist in the project area. 

Recreation and Land Use – Continued operation of the York Haven, Muddy Run, 

and Conowingo projects would enhance the recreational facilities and benefit 

recreationists in the region. Implementing a recreation management plan at the York 

Haven Project that includes a facility inventory with ownership and management 

responsibilities for each site, as well as measures to provide for periodic monitoring and 

consultation and protection of human safety during construction of the nature-like 

fishway, would ensure that recreational opportunities are maintained and enhanced. 

Revising the York Haven Project boundary to include the entirety of the Lock 15 

facility would bring a facility associated with the East Shore boat launch within the 

project boundary. 

Implementing the proposed Recreation Management Plans at the Muddy Run and 

Conowingo projects that include measures for maintenance and capital improvement, 

with staff modifications that include providing angler access to the catwalk at 

Conowingo, would ensure that the visitation and facilities are monitored periodically to 

ensure that the project recreation facilities continue to meet recreation use and demand at 

the projects.

Revising the Conowingo project boundary to remove lands that were necessary 

during construction of the project but are no longer used for project purposes (such as 

project-related recreation or protection of environmental resources not related to the 

project) would be consistent with FERC policy that only lands and waters needed for 

project purposes should be included in the project boundary. 

Cultural Resources – Continued operation of the York Haven, Muddy Run, and 

Conowingo projects could affect historic properties located within the projects’ 

boundaries. Implementing York Haven Power’s and Exelon’s HPMPs with the staff 

modifications to the plans for the York Haven and Conowingo projects would provide for 

the management and protection of cultural resources and any historic properties 

associated with the projects. 
xl

No-Action Alternative

Under the no-action alternative, the projects would continue to operate under the 

terms and conditions of the existing licenses, and no new environmental protection, 

mitigation, or enhancement measures would be implemented.

Conclusions

Based on our analysis, we recommend licensing the projects as proposed by York 

Haven Power and Exelon with some staff modifications and additional measures.

In section 4.2, Comparison of Alternatives, we estimate the likely cost of 

alternative power for each of the alternatives identified above. For the York Haven 

Project, our analysis shows that, during the first year of operation under the proposed 

action, the project would produce power at a cost which is $336,690 or $2.56/megawatthour (MWh) more than the cost of alternative power. Under the staff alternative, the 

project would produce power at a cost which is $332,650 or $2.52/MWh more than the 

cost of alternative power.

For the Muddy Run Project, our analysis shows that, during the first year of 

operation under the proposed action, the project would produce power at a cost which is 

$50,233,890 or $31.09/MWh less than the cost of alternative power. Under the staff 

alternative, the project would produce power at a cost which is $50,498,040 or 

31.28/MWh less than the cost of alternative power.

For the Conowingo Project, our analysis shows that, during the first year of 

operation under the proposed action, the project would produce power at a cost which is 

$32,270,040 or $17.70/MWh less than the cost of alternative power. Under the staff 

alternative, the project would produce power at a cost which is $31,099,900 or 

$17.06/MWh less than the cost of alternative power.

We chose the staff alternatives as the preferred alternatives for the Susquehanna 

River Projects because: (1) the York Haven, Muddy Run, and Conowingo projects 

would provide a dependable source of electrical energy and ancillary services for the 

region (131,771 MWh, 1,614,313 MWh, and 1,823,293 MWh annually, respectively); 

(2) the combined 1,394.16 MW of electric capacity comes from a renewable resource that 

does not contribute to atmospheric pollution; and (3) the recommended environmental 

measures proposed by York Haven Power and Exelon, as modified by staff, would 

adequately protect and enhance environmental resources affected by the projects. The 

overall benefits of the staff alternatives would be worth the cost of the proposed and 

recommended environmental measures.
1

1.0 INTRODUCTION

1.1 APPLICATION

On August 30, 2012, York Haven Power Company, LLC (York Haven Power)

filed an application for a new license with the Federal Energy Regulatory Commission 

(Commission or FERC) for the existing York Haven Project (FERC Project No. 1888).15 

The 19.62-megawatt (MW) project is located on the Susquehanna River at river mile 

(RM)16 55 in the city of York, in York, Dauphin, and Lancaster counties, Pennsylvania 

(figure 1-1). The project does not occupy any federal lands. The project generates an 

average of about 132,271 megawatt-hours (MWh) of energy annually. York Haven 

Power proposes no new capacity and no new construction; however, the company is 

proposing the construction of a new fishway as part of its proposed 

environmental measures.

On August 29, 2012, Exelon Generation Company, LLC (Exelon) filed 

applications for new licenses with the Commission for the existing Muddy Run Pumped 

Storage Project (Muddy Run Project) (FERC Project No. 2355)17 and the existing 

Conowingo Hydroelectric Project (Conowingo Project).

18 The 800.25-MW Muddy Run 

and the 574.54-MW Conowingo projects are located on the Susquehanna River at RM 22 

and RM 10, respectively, in Lancaster and York counties, Pennsylvania, and Cecil and 

Harford counties, Maryland (figure 1-1).

19 Conowingo Pond acts as the lower reservoir 

for the Muddy Run Project. Neither project occupies any federal lands. The Muddy Run 

and Conowingo projects generate an average of about 1,615,813 MWh and 

1,823,193 MWh of energy annually, respectively. Exelon proposes no new capacity and 

no new construction at either project. 

 

15 The current license for the York Haven Project was issued on August 14, 1980, 

and expires on September 1, 2014. 

16 The river mile is calculated from the mouth of the Susquehanna River at its 

confluence with the Chesapeake Bay. 

17 The current license for the Muddy Run Project was issued on September 21, 

1964, and expires on August 31, 2014. 

18 The current license for the Conowingo Project was issued on August 14, 1980, 

and expires on September 1, 2014. 

19 The authorized capacity for Muddy Run is from the original license issued 

September 21, 1964, and the authorized capacity for Conowingo is from the Commission 

Order issued March 3, 2010.
2

Figure 1-1. Susquehanna River Projects location (Source: FERC, 2009, as modified by 

Staff).
3

1.2 PURPOSE OF ACTION AND NEED FOR POWER

1.2.1 Purpose of Action

The purpose of the York Haven, Muddy Run, and Conowingo projects 

(Susquehanna River Projects) is to continue to provide a source of hydroelectric power. 

Therefore, under the provisions of the Federal Power Act (FPA), the Commission must 

decide whether to issue a license to York Haven Power for the York Haven Project and to 

Exelon for the Muddy Run and Conowingo projects and what conditions should be 

placed on any licenses issued. In deciding whether to issue a license for a hydroelectric

project, the Commission must determine that the projects will be best adapted to a 

comprehensive plan for improving or developing a waterway. In addition to the power 

and developmental purposes for which licenses are issued (such as flood control, 

irrigation, or water supply), the Commission must give equal consideration to the 

purposes of: (1) energy conservation; (2) the protection of, mitigation of damage to, and 

enhancement of fish and wildlife resources; (3) the protection of recreational 

opportunities; and (4) the preservation of other aspects of environmental quality.

Issuing new licenses for the Susquehanna River Projects would allow York Haven 

Power and Exelon to generate electricity at the projects for the term of each new license, 

making electric power from a renewable resource available to their customers. This 

multi-project draft environmental impact statement (EIS) assesses the effects associated 

with operation of the projects, alternatives to the proposed projects, and makes 

recommendations to the Commission on whether to issue a new license, and if so, 

recommends terms and conditions to become a part of any licenses issued.

In this draft EIS, we assess the environmental and economic effects of continuing 

to operate the projects: (1) as proposed by York Haven Power and Exelon; and (2) with 

our recommended measures. We also consider the effects of the no-action alternative. 

Important issues that are addressed include the effects of continued project operation on 

shoreline erosion and sediment transport, water quality, fishery resources and fish 

passage, terrestrial resources, threatened and endangered species, recreation and land use, 

and cultural resources. 

1.2.2 Need for Power

The Susquehanna River Projects provide hydroelectric generation to meet part of 

Maryland’s and Pennsylvania’s power requirements, resource diversity, and capacity 

needs. The existing York Haven Project has an installed capacity of 19.62 MW and 

generates approximately 132,271 MWh per year (average 2001-2011). The existing 

Muddy Run Project has an installed capacity of 800.25 MW and generates approximately 

1,615,813 MWh per year (average 1996-2010). The existing Conowingo Project has an 

installed capacity of 574.54 MW and generates approximately 1,823,193 MWh per year 

(1996-2010). 
4

The North American Electric Reliability Corporation (NERC) annually forecasts 

electrical supply and demand nationally and regionally for a 10-year period. The projects 

are located in the Pennsylvania-New Jersey-Maryland region of NERC. According to 

NERC’s 2013 forecast, the summer and winter planning reserve margins (capacity 

resources in excess of demand) are expected to drop from 32.04 percent in 2014 to 19.73 

percent in 2023 and from 42.99 percent in 2014 to 32.87 percent in 2023, respectively

(NERC, 2013). 

In addition to energy and capacity, the Conowingo and Muddy Run projects 

provide ancillary services that benefit the electric grid. The Conowingo Project provides 

peaking generation, regulation control, and black start capabilities. The Muddy Run 

Project provides peaking generation, peak load following, spinning reserve, and black 

start capability, and also is able to use excess baseload energy during pumping operation.

Baseload facilities operate at maximum output. They shut down or reduce power 

only to perform maintenance or repairs. Baseload facilities typically include coal, fuel 

oil, nuclear, hydroelectric, geothermal, biomass, and combined cycle natural gas 

facilities.

Pumped storage facilities can be operated at a generating level that is much lower 

than baseload facilities and can therefore avoid the need to run a baseload unit at low 

efficiencies below the minimum load rating of the baseload unit. Pumped storage 

facilities can also use excess energy provided by baseload units that run continuously at 

night to pump water to the upper reservoir so that it can be used for generation during 

daily peak demand periods.

Peaking facilities operate during times of peak electric demand. Conowingo and 

Muddy Run have the ability to meet peak energy demands by increasing generation 

needed when water is available. They have the ability to start within minutes, if not 

seconds, depending upon available water supply. Muddy Run is able to draw from 

storage in the Muddy Run Project reservoir (the upper reservoir) when needed to provide 

peak generation, while Conowingo relies on inflows and impoundment storage.

Spinning reserve is the extra generating capacity that is available by increasing the 

power output of generators that are already connected to the power grid. Facilities like 

Muddy Run that provide spinning reserve can be on line, synchronized with the electric 

grid, and quickly add power to the system as needed. Muddy Run can also perform “load 

following,” whereby the output of the facilities is increased or decreased in response to 

variations in electric demand.

Hydroelectric facilities can also provide frequency and/or voltage regulation 

benefits to the system. Operating in frequency control mode, they alter their output to 

keep the system frequency near the required value to avoid system imbalance. Similarly, 

they can also provide system voltage control.

Black start is the procedure to recover from a total or partial shutdown of the 

transmission system, such as the blackout that occurred in August 2003, which was the 
5

largest ever blackout of the North American power grid. The outage affected an 

estimated 50 million people and more than 70,000 MW of electrical load in parts of Ohio, 

Michigan, New York, Pennsylvania, New Jersey, Connecticut, Massachusetts, Vermont, 

and the Canadian provinces of Ontario and Quebec. Power was successfully restored to 

most customers within hours, while some areas in the United States did not have power 

for 2 days, and parts of Ontario experienced rotating blackouts for up to 2 weeks. 

Conowingo and Muddy Run were some of the first units used to bring the system back on 

line. These facilities were started individually and gradually brought on line to stabilize 

the system before the baseload units were brought back on line.

We conclude that power from the projects would help meet a need for power and 

ancillary services in the Pennsylvania-New Jersey-Maryland region in both the short- and 

long-term. The projects would provide low-cost power that displaces generation from 

non-renewable sources. Displacing the operation of non-renewable facilities may avoid 

some power plant emissions, thus creating environmental benefits.

1.3 STATUTORY AND REGULATORY REQUIREMENTS

Licenses for the Susquehanna River Projects are subject to numerous requirements 

under the FPA and other applicable statutes. We summarize the major regulatory 

requirements in table 1-1 and describe them below. 

Table 1-1. Major statutory and regulatory requirements for the Susquehanna River

Projects.

Requirement Agency Status

Section 18 of the FPA

(fishway prescriptions)

U.S. Department of the 

Interior (Interior); National 

Marine Fisheries Service

(NMFS)

Interior filed preliminary 

fishway prescriptions for the 

York Haven Project on 

January 30, 2014, and for the 

Muddy Run and Conowingo

projects on January 31, 2014.

NMFS filed reservations of 

authority for the Muddy Run 

and Conowingo projects on 

January 30, 2014.

Section 10(j) of the FPA Interior; Pennsylvania Fish 

and Boat Commission

(Pennsylvania FBC)

Interior filed 10(j) 

recommendations for the 

York Haven, Muddy Run,

and Conowingo projects on 

January 30 and 31, 2014; 

Pennsylvania FBC filed 10(j) 

recommendations for the 
6

Requirement Agency Status

Conowingo Project on 

December 11, 2013.

Clean Water Act—water 

quality certification

Pennsylvania Department 

of Environmental 

Protection (Pennsylvania 

DEP); Maryland 

Department of the 

Environment (Maryland 

DOE)

York Haven Project –

Pennsylvania DEP received 

an application for water 

quality certification on 

August 29, 2013;

certification is due 

August 28, 2014.

Muddy Run Project – Exelon 

applied to Pennsylvania DEP 

for certification on 

August 28, 2013;

Pennsylvania DEP issued a 

certification for the Muddy 

Run Project on June 3, 2014.

Conowingo Project –

Maryland Department of 

Natural Resources received 

an application for 

certification on January 31, 

2014; certification is due 

January 30, 2015.

Endangered Species Act 

Consultation

U.S. Fish and Wildlife 

Service (FWS) 

We will seek concurrence 

from FWS on our not likely 

to adversely affect 

determinations for the bog 

turtle, Indiana bat, shortnose 

sturgeon, and Atlantic

sturgeon.

Coastal Zone 

Management Act 

Consistency

Pennsylvania Coastal 

Resource Management 

Program (Pennsylvania 

CRM Program); Maryland 

DOE

Pennsylvania CRM Program 

determined both York Haven 

and Muddy Run are located 

outside the state’s coastal 

zone and would not affect 

coastal resources; Maryland 

DOE has until January 30, 

2015 to determine 

consistency.
7

Requirement Agency Status

National Historic 

Preservation Act

Pennsylvania State 

Historic Preservation 

Officer (Pennsylvania 

SHPO); Maryland SHPO

A Programmatic Agreement 

is to be executed between the 

Commission and the SHPOs.

1.3.1 Federal Power Act

1.3.1.1 Section 18 Fishway Prescriptions

Section 18 of the FPA states that the Commission is to require construction, 

operation, and maintenance by a licensee of such fishways as may be prescribed by the 

Secretaries of Commerce and Interior. 

On January 30, 2014, the U.S. Department of the Interior (Interior) timely filed a 

preliminary fishway prescription for the York Haven Project, including conditions 

consistent with a Settlement Agreement filed on January 30, 2014 (see section 1.5, 

Settlement Agreement). Interior filed a corrected version of the preliminary fishway 

prescription on February 7, 2014, requesting that it replace the original filing that 

contained inadvertent word processing artifacts. These conditions are described under 

section 2.2, Applicants’ Proposals, York Haven Project. 

On January 31, 2014, Interior timely filed a fishway prescription for the Muddy 

Run and Conowingo projects, which it modified by letter filed on February 28, 2014. 

These conditions are described under section 2.2.4, Modifications to the Applicants’

Proposals – Mandatory Conditions. 

The National Marine Fisheries Service (NMFS), by letter dated January 30, 2014, 

requests that a reservation of authority to prescribe fish passage under section 18 be 

included in any license issued for the Muddy Run and Conowingo projects. 

1.3.1.2 Section 10(j) Recommendations

Under section 10(j) of the FPA, each hydroelectric license issued by the 

Commission must include conditions based on recommendations provided by federal and 

state fish and wildlife agencies for the protection, mitigation, or enhancement of fish and 

wildlife resources affected by the project. The Commission is required to include these 

conditions unless it determines that they are inconsistent with the purposes and 

requirements of the FPA or other applicable law. Before rejecting or modifying an 

agency recommendation, the Commission is required to attempt to resolve any such 

inconsistency with the agency, giving due weight to the recommendations, expertise, and 

statutory responsibilities of such agency.

Interior timely filed 10(j) recommendations for the York Haven Project on January 

30, 2014, and for the Muddy Run Project on January 31, 2014, and the Pennsylvania Fish 
8

and Boat Commission (Pennsylvania FBC) and Interior timely filed, on December 11, 

2013, and January 31, 2014, respectively, recommendations under section 10(j) for the 

Conowingo Project. These recommendations are summarized in table 5-1, in section 5.3, 

Fish and Wildlife Agency Recommendations. In section 5.3, we discuss how we address 

the agency recommendations and comply with section 10(j).

1.3.2 Clean Water Act

Under section 401 of the Clean Water Act, a license applicant must obtain either 

certification from the appropriate state water pollution control agency verifying 

compliance with the Clean Water Act or a waiver of certification by the appropriate 

agency. Here, the facilities of the York Haven and Muddy Run projects are located in 

Pennsylvania and the discharges from these two projects are located in Pennsylvania. 

The Conowingo Project facilities are located in both Pennsylvania and Maryland, but the 

discharge occurs in Maryland. Therefore, the Pennsylvania Department of 

Environmental Protection (Pennsylvania DEP) is the appropriate state water pollution 

certifying agency to act on York Haven Power’s request for the York Haven Project and 

Exelon’s request for the Muddy Run Project. The Maryland Department of the 

Environment (Maryland DOE) is the appropriate agency to act on Exelon’s request for 

the Conowingo Project. 

York Haven Project

On August 29, 2013, York Haven Power applied to Pennsylvania DEP for 

401 water quality certification (certification) for the York Haven Project. Pennsylvania 

DEP received this request on August 29, 2013. Pennsylvania DEP has not yet acted on 

the request. The certification is due by August 28, 2015. 

Muddy Run Project

On August 28, 2013, Exelon applied to Pennsylvania DEP for the Muddy Run 

Project. Pennsylvania DEP issued certification on June 3, 2014. In its reply comments 

filed on March 18, 2014, Exelon requested that the Commission incorporate the 

conditions of the draft certification into Exelon’s licensing proposal and reflect the 

conditions as Exelon’s preferred alternative in the EIS. While Exelon has not indicated 

the final certification represents its proposal, our review of the draft and final 

certifications found that they are nearly identical, and therefore this EIS treats the 

conditions in the certification as part of Exelon’s proposal. The certification conditions

are summarized here and described in detail in sections 3.3.1.2, Geology and Soils,

Environmental Effects, and 3.3.2.2, Water Resources, Environmental Effects:

• Develop a dissolved oxygen (DO) monitoring plan no earlier than 

November 1, 2027, with measures designed to ensure that the project does 

not violate DO standards.
9

• Develop fish passage operating procedures (FPOP) for upstream and 

downstream fish passage, with specific targets for upstream and 

downstream passage at the Muddy Run Project, and corrective actions if 

targets are not met. 

• Develop a plan and schedule, as part of the fish passage requirements, for a 

radio telemetry study or equivalent Tier II study of American shad passage 

and behavior within the Muddy Run Project boundary if resource agencies 

determine that operation of the Muddy Run Project is causing the Holtwood 

Project to fail to meet its Tier I upstream American shad target specified in 

the water quality certification for the Holtwood Project.20

• Implement the American Eel Passage Plan for an eel trap and truck 

program to trap, hold, and transport American eels from the Conowingo 

Project and Octoraro Creek to designated points in the Susquehanna River 

watershed until at least 2030, and then either continue the trap and truck 

program or construct a volitional eel passage facility at Conowingo dam. 

• Once every 10 years through the term of the license, evaluate all state and 

federal endangered and threatened species that may be present within the 

project boundary, and if the evaluation identifies the presence, critical 

habitat, or critical dependence of endangered species, propose and 

implement a protection plan for each species. 

• Provide annual grants up to $450,000 equally to the Lancaster County and 

York County Conservation Districts for the implementation of agricultural 

pasture and barnyard best management practices (BMPs) to control 

sediment loading to the Susquehanna River.

• Provide $50,000 annually to the Pennsylvania FBC to perform habitat 

improvement projects including removal of small dams. 

• Provide the version of the Lower Susquehanna River OASIS Model to the 

Susquehanna River Basin Commission (SRBC) as provided in the Letter 

Agreement Addressing Exelon’s Provision of an OASIS Model to SRBC 

dated November 19, 2013.

 

20 The Tier I target under the Holtwood Project certification is that at least 

75 percent of the shad that pass the downstream Conowingo Project also pass through the 

Holtwood Project fish passage facilities. If the Tier I target is not met after 3 years of 

studies, then 4 years of Tier II studies would be conducted using radio telemetry and 

other methodologies to determine if at least 85 percent of the shad that enter Holtwood 

Project waters successfully pass through the Holtwood fish facilities. 
10

Conowingo Project

On January 30, 2014, Exelon applied to Maryland DOE for certification for the 

Conowingo Project. Maryland DOE received this request on January 30, 2014, and has

not yet acted on the request. The certification is due by January 30, 2015.

1.3.3 Endangered Species Act

Section 7 of the Endangered Species Act (ESA) requires federal agencies to ensure 

that their actions are not likely to jeopardize the continued existence of endangered or 

threatened species or result in the destruction or adverse modification of the critical 

habitat of such species. Six federally listed species are known to occur in the general

vicinity of one or more of the projects: shortnose sturgeon (Acipenser brevirostrum), 

Atlantic sturgeon (Acipenser oxyrinchus oxyrinchus), bog turtle (Glyptemys [Clemmys] 

muhlenbergii), Indiana bat (Myotis sodalis), Delmarva Peninsula fox squirrel (Sciurus 

niger cinereus), and swamp pink (Helonias bullata) (letters from FWS, to K.D. Bose, 

Secretary, FERC, Washington, D.C., January 4, 2007).21 Our analysis of project impacts 

on threatened and endangered species is presented in section 3.3.4, Threatened and 

Endangered Species, and our recommendations in section 5.1, Comprehensive 

Development and Recommended Alternative.

We conclude that relicensing of the York Haven and Muddy Run projects would 

have no effect on the shortnose or Atlantic sturgeon because neither species is known to 

have been collected or passed via the Conowingo fish lifts since they began operation in 

1972. While there is suitable habitat downstream of Conowingo for both species, there is 

no evidence of their occurrence in the lower Susquehanna River. Therefore, continued 

operation of the York Haven, Muddy Run, and Conowingo projects would not likely 

adversely affect the shortnose and Atlantic sturgeon.

Bog turtles have been confirmed near the Muddy Run Project. Implementing 

Exelon’s Bog Turtle Management Plan for the Muddy Run Project, including habitat 

management at any confirmed breeding locations and other practices to protect the 

existing population and improve bog turtle habitat would minimize effects on bog turtles 

and their habitat due to project maintenance or recreation. Therefore, we conclude that 

 

21 On June 5, 2013, staff requested updated species information from FWS for 

threatened and endangered species in the vicinity of the projects. The Pennsylvania 

Game Commission responded and provided information on state-listed birds and 

mammals in the vicinity of the three projects in a letter filed July 2, 2013. Staff also 

referred to FWS’ website (http://ecos.fws.gov/ipac/; accessed March 11, 2014 and 

May 12, 2014) to gather recent information on the potential presence of federally listed 

threatened and endangered species within the counties that contain the three projects, and 

contacted FWS and Maryland DNR regarding a bog turtle record close to Conowingo 

dam (see telephone and e-mail memoranda of April 23, 2014 and June 9, 2014).
11

relicensing the Muddy Run Project may affect, but would not be likely to adversely affect 

the bog turtle. 

For the Conowingo Project, although Interior states that bog turtles have been 

observed close to the Conowingo dam and recommends a bog turtle management plan, it 

has yet to provide evidence to indicate that bog turtles are present within the Conowingo 

Project boundary. Exelon conducted a bog turtle habitat study in 2008 and concluded 

that no project wetlands contained bog turtle habitat. Thus, staff cannot presently 

determine if bog turtles would be affected by the Conowingo Project. Further 

consultation with Interior is necessary to determine the potential for project effects and 

the need for Interior’s recommended bog turtle management plan.

Potential Indiana bat habitat may exist within the three project areas, along the 

riparian forested edges of the river and reservoirs, and forested edges along transmission 

line rights-of-way and recreational areas. Neither York Haven Power nor Exelon propose 

any activities that would result in more than a minimal amount of tree clearing. At the 

Muddy Run Project, continued routine vegetation management practices, such as 

trimming and herbicide application, would be unlikely to affect trees large enough to 

provide roosting habitat. Therefore, the York Haven, Muddy Run, and Conowingo 

projects would not be likely to adversely affect the Indiana bat. 

Because the swamp pink is not listed by the U.S. Fish and Wildlife Service (FWS)

as occurring in the counties occupied by York Haven or Muddy Run projects, these 

projects would have no effect on the species and it is not analyzed further in this 

document. Although swamp pink has been previously documented in Cecil and Harford 

counties where the Conowingo Project is located, we conclude the Conowingo Project 

would have no effect on the swamp pink because this species is not known to occur in 

those project areas according to FWS’ Information, Planning, and Conservation 

System website. 

The three projects would have no effect on the Delmarva Peninsula fox squirrel 

because it is not known to exist in the projects’ action areas.

1.3.4 Coastal Zone Management Act

Under section 307(c)(3)(A) of the Coastal Zone Management Act (CZMA), 

16 U.S.C. § 1456(3)(A), the Commission cannot issue a license for a project within or 

affecting a state’s coastal zone unless the state CZMA agency concurs with the license 

applicant’s certification of consistency with the state’s CZMA program, or the agency’s 

concurrence is conclusively presumed by its failure to act within 180 days of its receipt of 

the applicant’s certification.

The York Haven and Muddy Run projects are not located within the Pennsylvaniadesignated coastal management zone. The projects are located outside of Pennsylvania’s 

Lake Erie and Delaware Coastal Zones, and the projects would not affect Pennsylvania’s

coastal resources. Therefore, the projects are not subject to Pennsylvania coastal zone 
12

program review, and no consistency certification is needed for the action. By emails 

dated June 24, and December 10, 2009, the Pennsylvania Coastal Resource Management 

Program concurred.

On September 4, 2012, Exelon filed a letter with the Maryland Consistency 

Coordinator of the Maryland DOE stating that the Conowingo Project complies with the 

enforceable polices of the Maryland Coastal Zone Management Program and would be 

operated in a manner consistent with this program. On March 5, 2013, the Maryland 

Office of the Attorney General filed a letter with the Commission that included a written 

agreement between Maryland and Exelon to extend the coastal zone consistency review 

period to 1 year from when Exelon files its request for certification. Exelon filed its 

request for certification with Maryland DOE on January 30, 2014, and with the 

Commission on January 31, 2014. Consequently, a coastal zone management program 

consistency determination is due from Maryland by January 30, 2015.

1.3.5 National Historic Preservation Act

Section 106 of the National Historic Preservation Act (NHPA) requires that every 

federal agency “take into account” how each of its undertakings could affect historic

properties. Historic properties are districts, sites, buildings, structures, traditional cultural 

properties, and objects significant in American history, architecture, engineering, and 

culture that are eligible for inclusion in the National Register of Historic Places 

(National Register). 

In response to York Haven Power’s May 29, 2009, request, and Exelon’s 

March 12, 2009, request, the Commission designated York Haven Power and Exelon as

non-federal representatives for the purposes of conducting section 106 consultation under 

the NHPA on July 24, 2009, and May 11, 2009, respectively. Pursuant to section 106, 

and as the Commission’s designated non-federal representative, York Haven Power 

consulted with the Pennsylvania State Historic Preservation Officer (SHPO) and affected 

Indian tribes, and Exelon consulted with the Pennsylvania and Maryland SHPOs to 

locate, determine National Register eligibility, and assess potential adverse effects on

historic properties associated with the projects. 

In April 2012, York Haven Power prepared a draft Historic Properties 

Management Plan (HPMP) to address project-related effects on historic properties and 

unevaluated cultural resources. The Pennsylvania SHPO provided comments on the draft 

HPMP (letter from D.C. McClearen, Chief, Division of Archaeology and Protection, 

Pennsylvania Historical and Museum Commission, Bureau for Historic Preservation, 

Harrisburg, Pennsylvania, to D. Weaver, York Haven Power Company, York Haven, 

Pennsylvania, September 14, 2012), and York Haven Power addressed those comments 

in a revised HPMP filed with the Commission on December 28, 2012 (Stallings and 

Franz, 2012).

In its application, Exelon stated that continued operation of the Muddy Run 

Project would not affect historic properties that are listed or eligible for listing on the 
13

National Register. For this reason, an HPMP for the Muddy Run Project was not 

developed. However, Exelon proposes a license article that would require section 106 

consultation prior to any project-related ground-disturbing activity, including recreational 

development, and a requirement to develop a cultural resources management plan should 

any previously unidentified cultural materials be discovered during project activities.

In December 2012, Exelon prepared an HPMP to address project-related effects on 

historic properties and unevaluated cultural resources at the Conowingo Project (Sara et 

al., 2012). No comments on the HPMP received from the Pennsylvania SHPO or 

Maryland SHPO have been filed with the Commission.

To meet the requirements of section 106, the Commission intends to execute 

Programmatic Agreements (PAs) for the protection of historic properties from the effects 

of the operation of the York Haven Project, Muddy Run Project, and Conowingo Project. 

The terms of the PAs would ensure that York Haven Power and Exelon address and treat 

all historic properties identified within the projects’ areas of potential effects (APE) 

through the finalization of the existing draft HPMPs for the York Haven Project and the 

Conowingo Project and the development of an HPMP for the Muddy Run Project.

1.3.6 Magnuson-Stevens Fishery Conservation and Management Act 

The Magnuson-Stevens Fishery Conservation and Management Act requires 

federal agencies to consult with NMFS on all actions that may adversely affect essential 

fish habitat. In correspondence during scoping and in response to the ready for 

environmental analysis notices, NMFS did not identify any essential fish habitat in 

segments of the Susquehanna River affected by the projects. Therefore, we conclude that 

the Susquehanna River Projects would have no effect on essential fish habitat. 

1.4 PUBLIC REVIEW AND COMMENT

The Commission’s regulations (18 Code of Federal Regulations [CFR]

§§5.1-5.16) require that applicants consult with appropriate resource agencies, tribes, and 

other entities before filing an application for a license. This consultation is the first step 

in complying with the Fish and Wildlife Coordination Act, ESA, NHPA, and other 

federal statutes. Prefiling consultation must be complete and documented according to 

the Commission’s regulations

1.4.1 Scoping

Before preparing this draft EIS, we conducted scoping to determine what issues 

and alternatives should be addressed. Scoping documents (SD1s) were distributed to 

interested agencies and others for the York Haven Project on July 24, 2009, and for the 

Muddy Run and Conowingo projects on May 11, 2009. A publicly noticed scoping 

meeting for the York Haven Project was held in New Cumberland, Pennsylvania, during 

the evening of August 26, 2009, and a second daytime meeting was held in Harrisburg, 

Pennsylvania, on August 27, 2009. A publicly noticed evening scoping meeting for the 
14

Muddy Run Project was held on June 10, 2009, in Holtwood, Pennsylvania, and for the 

Conowingo Project on June 11, 2009, in Darlington, Maryland. A joint daytime meeting 

to discuss both the Muddy Run and Conowingo projects was held on June 12, 2009, in 

Darlington, Maryland. A court reporter recorded all comments and statements made at 

the scoping meetings, and these are part of the Commission’s public record for the 

projects. In addition to comments provided at the scoping meetings, the following 

entities provided written comments.

Commenting Entities Date Filed

York Haven Project

York Haven Planning Commission August 7, 2009

Honorable Todd Platts September 21, 2009

Pennsylvania Department of Natural Resources September 24, 2009

York Haven Power Company, LLC September 28, 2009

Borough of Goldsboro September 28, 2009

The Nature Conservancy September 29, 2009

U.S. Fish and Wildlife Service September 29, 2009

Susquehanna River Basin Commission September 29, 2009

Pennsylvania Fish and Boat Commission September 29, 2009

Exelon Generation Company, LLC September 29, 2009

U.S. Army Corps of Engineers September 29, 2009

Pennsylvania Department of Environmental Protection September 29, 2009

James Toothaker October 5, 2009

Cynthia Gross October 5, 2009

Muddy Run Project

Maryland Department of Natural Resources July 10, 2009

Susquehanna River Basin Commission July 10, 2009

U.S. Fish and Wildlife Service July 10, 2009

Pennsylvania Fish and Boat Commission July 10, 2009

Pennsylvania Department of Environmental Protection July 10, 2009

Conowingo Project

Town of Port Deposit June 16, 2009

Alex Balboa June 19, 2009

Ronald Steelman July 6, 2009

Susquehanna River Basin Commission July 10, 2009

Maryland Department of Natural Resources July 10, 2009

Pennsylvania Fish and Boat Commission July 10, 2009

Robert B. Campbell July 13, 2009

Jere Hess July 13, 2009

Pennsylvania Department of Environmental Protection July 13, 2009

Lower Susquehanna River Keeper July 13, 2009
15

U.S. Fish and Wildlife Service July 13, 2009

Honorable Benjamin L. Cardin August 3, 2009

Muddy Run and Conowingo Projects

American Rivers July 10, 2009

Exelon Corporation July 10, 2009

Lancaster County Planning Commission July 10, 2009

The Nature Conservancy July 10, 2009

National Marine Fisheries Service July 10, 2009

PPL Holtwood, LLC July 10, 2009

In addition to the commenting entities listed above for the York Haven Project, 

more than 1,400 individuals signed petitions that were filed between September 12 and 

October 5, 2009, opposed to the decommissioning of the York Haven Project.

22

A revised scoping document addressing these comments was issued for the York 

Haven Project on November 13, 2009, and on August 24, 2009, for the Muddy Run and 

Conowingo projects.

1.4.2 Interventions

On April 29, 2013, the Commission issued notices accepting the York Haven 

Power and Exelon applications to relicense the York Haven, Muddy Run, and 

Conowingo projects, and soliciting motions to intervene. These notices set 

September 30, 2013, as the deadline for filing protests and motions to intervene; 

however, by notices issued August 30, 2013, and December 13, 2013, the Commission 

granted extensions of time for stakeholders to file motions to intervene and protests until 

January 31, 2014. In response to the notices, the following entities filed motions 

to intervene:

Intervenors Date Filed

York Haven Project

PPL Brunner Island, LLC November 13, 2012

U.S. Department of the Interior May 31, 2013

 

22 A number of federal and state resource agencies, the SRBC, and The Nature 

Conservancy recommended that the Commission consider decommissioning as a 

reasonable alternative to relicensing. The Borough of Goldsboro, York Haven Power, 

and a petition signed by more than 1,400 individuals, requested that the Commission not 

consider project decommissioning as a reasonable alternative to relicensing. Those 

opposed to project decommissioning cite the potential loss of Lake Frederic, a significant 

economic and recreation resource in the area. 
16

Intervenors Date Filed

Susquehanna River Basin Commission June 11, 2013

Safe Harbor Water Power Corporation June 17, 2013

PPL Holtwood, LLC June 20, 2013

Pennsylvania Department of Environmental Protection June 21, 2013

Pennsylvania Fish and Boat Commission June 21, 2013

New Energy Capital Partners, LLC23 October 21, 2013

Exelon Corporation December 5, 2013

The Nature Conservancy January 31, 2014

American Rivers January 31, 2014

Maryland Department of Natural Resources, Maryland 

Department of the Environment January 31, 2014

Muddy Run Project

PPL Holtwood, LLC November 13, 2012

U.S. Department of the Interior May 31, 2013

Susquehanna River Basin Commission June 11, 2013

Safe Harbor Water Power Corporation June 17, 2013

Pennsylvania Department of Environmental Protection June 21, 2013

Pennsylvania Fish and Boat Commission June 21, 2013

New Energy Capital Partners, LLC September 27, 2013

Olympus Power Company, LLC December 6, 2013

NOAA Fisheries January 31, 2014

The Nature Conservancy January 31, 2014

American Rivers January 31, 2014

Maryland Department of Natural Resources, Maryland 

Department of the Environment January 31, 2014

Conowingo Project

Stewards of the Lower Susquehanna, Inc. September 7, 2012

PPL Holtwood, LLC November 13, 2012

U.S. Department of the Interior May 31, 2013

Susquehanna River Basin Commission June 11, 2013

Safe Harbor Water Power Corporation June 17, 2013

Pennsylvania Department of Environmental Protection June 21, 2013

Pennsylvania Fish and Boat Commission June 21, 2013

Clean Chesapeake Coalition June 25, 2013

Stewards of the Lower Susquehanna, Inc., Lower 

Susquehanna Riverkeeper, and Waterkeepers July 17, 2013

 

23 On November 4, 2013, York Haven Power filed a motion in opposition to the 

intervention of New Energy Capital Partners, LLC. The Commission issued a notice 

granting intervention on June 12, 2014.
17

Intervenors Date Filed

Chesapeake

Calpine Corporation July 24, 2013

Chesapeake Conservancy July 24, 2013

Chesapeake Bay Foundation August 20, 2013

Mason-Dixon Trail System, Inc. September 5, 2013

Citizens for Pennsylvania's Future September 25, 2013

New Energy Capital Partners, LLC September 27, 2013

The Susquehanna River Boater's Association, Peach 

Bottom Marina September 27, 2013

Cecil Land Use Association October 30, 2013

Olympus Power Company, LLC December 6, 2013

Midshore Riverkeeper Conservancy, Inc. December 11, 2013

Chester River Association and Sassafras River 

Association December 23, 2013

Onondaga Nation December 24, 2013

National Marine Fisheries Service January 30, 2014

The Nature Conservancy January 31, 2014

American Rivers January 31, 2014

Maryland Department of Natural Resources, Maryland 

Department of the Environment January 31, 2014

1.4.3 Comments on the Application

On April 29, 2013, the Commission issued Ready for Environmental Analysis 

notices for the three projects and requested comments, recommendations, preliminary 

terms and conditions, and preliminary fishway prescriptions. By notices issued 

August 30, 2013, and December 13, 2013, the Commission granted extensions of time for 

stakeholders to file comments, recommendations, and terms and conditions until 

January 31, 2014. The following entities filed comments, terms and conditions, 

recommendations, or prescriptions:

Commenting Agencies and Other Entities Date Filed

York Haven Project

Lancaster County Conservancy January 17, 2014

U.S. Department of the Interior January 30, 2014

The Nature Conservancy et al. January 31, 2014

American Rivers et al. January 31, 2014

Muddy Run Project

New Energy Capital Partners

Lancaster County Conservancy

National Marine Fisheries Service

November 22, 2013

January 17, 2014

January 31, 2014

U.S. Department of the Interior January 31, 2014

American Rivers et al. January 31, 2014
18

Commenting Agencies and Other Entities Date Filed

The Nature Conservancy et al. January 31, 2014

Conowingo Project

U.S. Environmental Protection Agency

New Energy Capital Partners

Henry Immanuel

Pennsylvania Fish and Boat Commission

Chesapeake Conservancy

Vicki Rinkerman

Lancaster County Conservancy

Midshore Riverkeeper Conservancy

August 6, 2013

November 19, 2013

November 19, 2013

December 11, 2013

December 13, 2013

December 13, 2013

January 17, 2014

January 29, 2014

National Marine Fisheries Service January 30, 2014

Citizens For Pennsylvania’s Future January 31, 2014

Maryland’s Department of Natural Resources 

and Department of the Environment

January 31, 2014

Clean Chesapeake Coalition January 31, 2014

City of Havre de Grace January 31, 2014

Town of Fort Deposit, Maryland January 31, 2014

Town of Perryville, Maryland January 31, 2014

Susquehanna River Basin Commission January 31, 2014

Harford County Government January 31, 2014

Cecil County Government January 31, 2014

Power Plant Research Program January 31, 2014

Chesapeake Bay Foundation January 31, 2014

Lower Susquehanna Heritage Greenway Inc. January 31, 2014

Stewards of the Lower Susquehanna Inc. January 31, 2014

U.S. Department of the Interior January 31, 2014

American Rivers et al. January 31, 2014

The Nature Conservancy et al. January 31, 2014
19

1.5 SETTLEMENT AGREEMENT

On January 30, 2014, York Haven Power, FWS, Pennsylvania FBC, Maryland 

Department of Natural Resources (Maryland DNR), and the SRBC24 (Settling Parties) 

filed a Settlement Agreement for the York Haven Project.

The Settlement Agreement resolves among the Settling Parties all issues 

associated with issuance of a new license for the project regarding upstream passage of 

American shad and American eels, downstream passage of juvenile and post-spawning 

American shad, downstream passage of silver stage American eel, resident fish passage, 

flow management, water quality and debris management, and endangered species and 

species of special concern. We consider the Settlement Agreement to represent the 

Proposed Action regarding these issues for this project.

On February 19, 2014, the Commission issued a Notice of Settlement Agreement. 

In response to that notice, PPL Brunner Island, LLC, filed a Protest and Comment in 

Opposition to the proposed Settlement Agreement. The basis for the opposition is that 

during low-flow periods, the measures specified in the Settlement Agreement could limit 

the amount of water available for withdrawal by the downstream Brunner Island Steam 

Electric Station which would restrict generation. York Haven Power filed a response to 

the opposition on March 4, 2014.

 

24 SRBC was established by the Susquehanna River Basin Compact, a federal 

interstate agreement among Maryland, Pennsylvania, and the United States. Pub. L. No. 

91-575, 84 Stat. 1509 (1970). Pursuant to the Compact, SRBC has duties and 

responsibilities for comprehensive planning, programming, and management of the water 

and related resources of the Susquehanna River Basin. 

In 1975, the Commission and SRBC entered into a Memorandum of 

Understanding. Under the November 5, 1975, Memorandum of Understanding, the

Commission and SRBC committed to cooperate in the processing of license applications 

to the extent feasible, and the Commission agreed to give due regard to any SRBC 

recommendations.
20

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21

2.0 PROPOSED ACTIONS AND ALTERNATIVES

2.1 NO-ACTION ALTERNATIVE

Under the no-action alternative, the Susquehanna River Projects would continue to 

operate under the terms and conditions of the existing licenses, and no new 

environmental protection, mitigation, or enhancement measures would be implemented. 

We use this alternative to establish baseline environmental conditions for comparison 

with other alternatives and to judge the benefits and costs of any measures that might be 

required under a new license.

2.1.1 Existing Project Facilities

Figure 2-1 shows the location and project boundaries of the Susquehanna 

River Projects.

2.1.1.1 York Haven Project

The project is located on the Susquehanna River in York, Dauphin, and

Lancaster counties in south central Pennsylvania (figure 2-2). The Susquehanna River

Basin above York Haven dam has a drainage area of about 24,973 square miles. The

project powerhouse is located at about RM 55, 17 miles downstream of the city

of Harrisburg.

The project is located upstream of the Muddy Run Project at about RM 22 and the 

Conowingo Project at about RM 10. The Three Mile Island nuclear station, also

owned by Exelon, is on Three Mile Island in Lake Frederic, the impoundment formed 

by York Haven dam. Pennsylvania Power and Light’s (PPL) Brunner Island Station, a

coal-fired steam electric generating plant, is located about 1.5 miles downstream of

the project.

The project includes an east channel dam, main dam, headrace wall, 

impoundment, powerhouse, substation, fish passage facilities, and recreation facilities. 

The project operates in a modified run-of-river mode, in that there is limited storage in 

the reservoir (about one hour worth of storage). During periods of moderate to high

runoff in the Susquehanna River that exceed the station’s maximum hydraulic capacity 

(about 17,000 cubic feet per second [cfs] under optimal head conditions), the project

cannot control water levels and spills water. Spills can occur at the main dam, headrace 

wall, and east channel structures.
22

Figure 2-1. Location and project boundaries for lower Susquehanna Projects (Source: 

Staff).
23

Figure 2-2. Project facilities for the York Haven Project (Source: Staff).
24

East channel dam is a concrete gravity overflow dam, which extends about 

928 feet in an easterly direction from the east shore of Three Mile Island to the east bank 

of the river. It has an average height of 9 feet. The crest of east channel dam is at 

elevation 278.95 feet National Geodetic Vertical Datum of 1929,

25 and it incorporates a 

vertical slot fishway. 

The main dam extends diagonally downstream approximately 4,970 feet from the

west shore of Three Mile Island to the upstream (north) end of the headrace wall. The

main dam is constructed of concrete-covered rock fill and rock fill/timber crib sections 

with a maximum height at the crest of 18 feet and an average height of 10 feet. The crest 

elevation of the majority of the main dam crest ranges from 277.86 feet26 to 278.78 feet. 

Two short sections of the dam crest are at about elevation 280.00 to 280.20 feet.

The stone masonry headrace wall extends 3,000 feet downstream from the

south end of the main dam to the powerhouse. The headrace wall serves to direct water

to the powerhouse. The elevation of the crest of the headrace wall includes sections at 

elevations 280.00 and 282.45 feet.

The project impoundment, Lake Frederic, is about 3.5 miles long with about

29 miles of total shoreline length within the project boundary, including the shoreline

of the islands in Lake Frederic. The maximum depth of Lake Frederic is about 18 feet 

with a mean depth of about 6 feet. At the normal water surface elevation of 

277.86 feet, Lake Frederic has a surface area of 2,218 acres and about 9,600 acre-feet of

gross storage capacity. Usable storage capacity is limited to the allowable 1.1-foot

fluctuation providing about 1,700 acre-feet of storage, or about 1 hour of storage at the

plant’s maximum hydraulic capacity.

The brick and stone masonry powerhouse is about 472 feet long and 48 feet

wide and is located parallel to the west bank of the Susquehanna River. This structure

contains the turbines, generators, and appurtenant power generating equipment. Steel

trashracks with 4-inch clear spacing are installed at the intakes at each of the

20 turbine-generator units. The forebay includes a trash sluice gate at its downstream

end that is 14 feet wide and 10.5 feet high. The sluice gate is capable of releasing about

600 cfs.

The powerhouse contains 20 turbine units with an installed capacity of 19.62 MW. 

Six are vertical shaft propeller turbines, and 14 are horizontal Francis turbines. 

 

25 Unless otherwise noted, all elevation data in this EIS are given in National 

Geodetic Vertical Datum of 1929. 26 The value of 277.86 feet represents the low point of the main dam, which under 

current operations is considered to be the normal elevation when river flows are less than 

the maximum turbine capacity of about 17,000 cfs.
25

Each of the turbines has a fixed gate and, therefore, no adjustments can be made to 

discharge less than the maximum turbine discharge other than reducing the water level in 

Lake Frederic. The minimum discharge from the powerhouse is about 700 cfs and occurs 

when only Unit 14 is operating. The project does not include a traditional tailrace, and

each of the units discharges directly into the Susquehanna River.

The project includes an outdoor substation that contains the station’s generator 

step-up transformers, station service transformers, and manual switching structures. 

There are no primary transmission lines included as part of the project, but it

interconnects with the 115-kilovolt (kV) electric grid at the substation immediately 

downstream of the project’s downstream forebay wall. A secondary service feed comes 

into the project substation via Line No. 722 at 13.2 kV.

The present upstream fish passage facility (the east channel fishway), located at

the western end of east channel dam and operational since April 2000, includes two

sections: a weir cut and a vertical-slot fish ladder. The weir cut section provides

supplemental attraction flows to the fishway, and the upper portion of the weir cut

includes three, 25-foot-diameter cofferdam cells between which two 20-foot-wide fixedwheel gates are installed, with each gate having a 1,000-cfs discharge capacity. The

lower section of the weir cut includes a 67-foot-wide adjustable weir and a stop gate. 

The 250-foot-long fish ladder has an entrance diffuser, serpentine baffles that form eight

pools, and an exit flume. A counting station is located in the exit channel just upstream

of the last fish ladder pool. 

York Haven Project recreation facilities include: the Historic Canal Lock, East 

Shore Boat Launch, Goosehorn Island Picnic Area, Shelley Island Recreation Area, 

Goodling Island Picnic Area, Beshore Island Recreation Area, Battery Island Recreation 

Area, Cly Shore recreational lot sites, York Haven Power Plant Recreation Area, and a 

Canoe Portage trail. These facilities are owned and operated by York Haven Power.

2.1.1.2 Muddy Run Project

The Muddy Run Project (figure 2-3) is a pumped storage hydroelectric generating 

facility 22 miles upstream of the Chesapeake Bay on the eastern shoreline of the 

Susquehanna River, within Drumore and Martic townships, Lancaster County, 

Pennsylvania. The project includes a Recreation Lake dam and spillway, main dam 

embankment, the east dike, upper reservoir spillway, canal dam embankment, upper 

reservoir (Muddy Run reservoir), intake structure, powerhouse, lower reservoir, a

primary transmission line, and recreation facilities.
26

Figure 2-3. Project facilities for the Muddy Run Project (Source: Staff).
27

Recreation Lake dam, located in the drainage for the upper reservoir about 2 miles 

upstream of the main dam, is a zoned earth and rockfill embankment. The dam is 

approximately 750 feet long, and it has a maximum height of about 90 feet and a crest 

width of 34 feet. The crest of the non-overflow section of the Recreation Lake dam is at 

elevation 530.00 feet. Recreation Lake dam includes a 4-foot-diameter concrete outlet 

pipe controlled from the upstream end by a flap gate. The Recreation Lake spillway 

consists of a nearly level rock cut channel approximately 140 feet wide with a concrete 

weir at crest elevation 520.00 feet. The spillway is traversed by a steel and concrete 

bridge that is used by pedestrian traffic and recreation area maintenance vehicles. 

Recreation Lake has a total storage capacity of 709 acre-feet and is maintained at a 

constant elevation of 520 feet for recreational purposes. The surface area is 

approximately 100 acres at that elevation.

The main embankment dam is constructed as a zoned embankment with an 

impervious core. The dam is 4,800 feet long and has a maximum height of 260 feet. The 

crest of the dam is at elevation 533.00 feet, and it is 34 feet wide and traversed by a 

20-foot-wide, two-lane roadway (River Road). The east dike is also a zoned earth and 

rock-fill embankment with an impervious core. The dike is approximately 800 feet long, 

has a crest width of 20 feet, and a maximum height of about 12 feet. The crest of the east 

dike is at elevation 530.80 feet.

The upper reservoir 200-foot-long ogee spillway is located on the west side of the 

intake canal. The spillway is 20 feet high, has a crest elevation of 521 feet, and 

discharges into a vegetated natural ravine that joins Muddy Run Creek just above its 

confluence with the Susquehanna River. The spillway is constructed within the canal 

dike and is flanked by concrete retaining walls. Since initial filling of the upper reservoir 

in 1967, the spillway has never been required to pass discharges from either natural 

inflows or over-pumping.

The canal embankment (also referred to as the intake channel dam), forms the 

upper part of the intake channel, which leads from the upper reservoir to the powerhouse 

intake structure. The lower part of the channel is excavated in rock. The embankment 

has a maximum height of about 35 feet and a minimum crest width of 25 feet. The 

upstream face of the embankment and the rock cut channel are lined with a 9-inch-thick 

reinforced concrete slab extending about 1,000 feet upstream on both sides of the canal 

from the powerhouse intake structure. The upstream portion of the canal is an unlined 

soil and rock cut. A bridge for River Road crosses this section of the canal.

The normal operating elevation of the upper reservoir ranges from 470 to 520 feet. 

At elevation 520 feet, the upper reservoir has a total storage capacity of 56,731 acre-feet 

with a usable capacity of 33,894 acre-feet, and a surface area of 892 acres. At the 

maximum drawdown elevation (470 feet), the upper reservoir has a surface area of 

471 acres.

The intake structure consists of four cylinder gates with trashracks having clear 

spacing of 5.37 inches. Each intake supplies two units and includes a cylindrical tower 
28

that leads to a 430-foot-deep vertical shaft. The vertical shaft and horizontal power 

tunnels are concrete lined with a diameter of 24.50 feet. The concrete-lined power 

tunnels bifurcate approximately 500 feet upstream of the powerhouse, transitioning to 

14-foot-diameter steel penstocks that connect to one of eight pump turbine units in the

powerhouse. There are no inlet valves at the downstream end of the penstocks.

The Muddy Run powerhouse is approximately 600 feet long by 133 feet wide, and 

is constructed entirely of concrete. The powerhouse is a semi-outdoor structure located 

on the east bank of the Susquehanna River and contains eight vertical-shaft, reversible 

pump-generating units that each have a rated capacity of 100 MW and a hydraulic 

capacity of 4,000 cfs, for a total discharge capacity of 32,000 cfs. The pumping capacity 

of the pump turbines is 3,500 cfs each, for a total powerhouse pumping capability of 

28,000 cfs. The units are equipped with trashracks, also with clear spacing of 5.75

inches, between the draft tube outlet and the river. 

The lower reservoir for the Muddy Run Project is Conowingo Pond, which is a 

portion of the Susquehanna River impounded by Conowingo dam. The lower reservoir 

has a total surface area of approximately 8,500 acres and approximately 310,000 acre-feet 

of gross storage at the maximum normal level of 109.2 feet. 

The primary transmission line consists of two 230-kV three-phase, three-wire 

circuits. The lines, owned by Exelon, but leased to the PECO Energy Company, an 

affiliate of Exelon, are identified as lines 220-06 and 220-07. Both lines begin at a 220-

kV switching station on the roof of the powerhouse and run about 4.25 miles to the Peach 

Bottom Atomic Power Station (PBAPS) North Substation located in York County. 

Muddy Run Project recreation facilities include: (1) Muddy Run Park (owned by 

Exelon, operated by a vendor); (2) Wissler’s Run Park (owned and operated by Exelon); 

and (3) Muddy Run Wildlife Management Area (WMA) (owned by Exelon and leased 

and managed by Pennsylvania Game Commission). 

Exelon holds title or rights to all project lands within the project boundary. The 

project boundary encompasses all of the project facilities and lands required for project 

operation and maintenance. However, only a portion of the 800-acre Muddy Run WMA

is within the existing project boundary.

2.1.1.3 Conowingo Project

The Conowingo Project (figure 2-4) consists of a main dam, spillway, reservoir 

(Conowingo Pond), intake structure, powerhouse, two fish lifts, and recreation facilities. 

The dam is a concrete gravity dam with a maximum height of 94 feet and a total length of 

4,648 feet. The dam has four distinct sections from east to west: a 1,190-foot-long,

non-overflow gravity section with a crest elevation of 115.70 feet; an ogee-shaped 

spillway, the major portion of which is 2,250 feet long with a crest elevation of 86.70

feet, and the minor portion of which is 135 feet long with a crest elevation of 99.2 feet; an 

intake-powerhouse section which is 946 feet long; and a 127-foot-long abutment section. 
29

Figure 2-4. Project facilities for the Conowingo Project (Source: Staff).
30

The tailrace and spillway sections of the dam are separated by a dividing wall 

extending 300 feet downstream of the powerhouse. The dam and powerhouse also 

support U.S. Route No. 1 which passes over the top of Conowingo dam.

Flow over the ogee spillway sections is controlled by 50 stony-type crest gates 

with crest elevations of 86.70 feet and two regulating gates with crest elevations of 

99.2 feet. Each crest gate is 22.50 feet high by 38 feet wide, and the gates have a 

collective discharge capacity of about 16,000 cfs at a reservoir elevation of 109.2 feet.

The two regulating gates are 10 feet high by 38 feet wide and have a discharge 

capacity of about 4,000 cfs per gate at a reservoir elevation of 109.2 feet. The effective 

usable storage between the licensed minimum and maximum pond elevations of 

101.2 feet and 110.2 feet is 75,287 acre-feet. 

Conowingo Pond extends 14 miles upstream from Conowingo dam to the lower 

end of the Holtwood Project (FERC Project No. 1881) tailrace. Conowingo Pond is 

generally maintained at an elevation of 109.2 feet, with a surface area of about 

8,500 acres and a total impoundment volume of 310,000 acre-feet at that elevation. The 

pond serves as the lower reservoir for the Muddy Run Project, located 12 miles upstream 

of Conowingo dam.

The intakes for each turbine are individually protected by seven trashracks; the 

five lower racks are entirely steel with a clear spacing of 5.37 inches, and top two are 

steel-framed with wood racks with a clear spacing of 4.75 inches. 

The 13 project generating units have a total installed capacity of 574.54 MW. The 

estimated total maximum hydraulic capacity of the project is about 86,000 cfs under 

optimum head conditions. Units 1 through 7 and the two house (station service) units are 

completely enclosed within the powerhouse, while Units 8 through 11 are of outdoor type 

construction, without superstructure.

The powerhouse enclosing Units 1 through 7 includes a generator room and an 

electrical bay. The electrical bay is located between the generator room and the 

powerhouse intakes and consists of the 13.8-kV bus and switching equipment. 

The tailrace is approximately 2,800 feet long, extending from the powerhouse to 

the downstream end of Rowland Island. The tailrace width ranges from about 900 feet 

near the powerhouse to 1,500 feet near Rowland Island. The tailwater elevation 

downstream of the dam, which varies with discharge, is at an approximate elevation of 

20.5 feet with all units operating with no spillway discharge. 

The project currently operates two fish lifts: the west fish lift and the newer east 

fish lift. There are no primary transmission lines associated with the project. Electricity 

generated at the project is transmitted by two 220-kV generation leads extending from the 

project substation to the East Nottingham substation.

The Conowingo Project recreation facilities include: Lock 13, Lock 15, Muddy 

Creek Boat Launch, Cold Cabin Boat Launch, Dorsey Park, Line Bridge, Broad Creek 
31

Public Landing, Glen Cove Marina, Conowingo Swimming Pool and Visitor’s Center, 

Peach Bottom Marina, Conowingo Creek Boat Launch, Funk’s Pond, Fisherman’s 

Park/Shures Landing, Conowingo Dam Overlook, and the Octoraro Creek Access area. 

Exelon operates seven of these facilities and leases the other eight to local and state 

entities or commercial operators. 

Exelon holds title or rights to all of the lands within the project boundary. The 

project boundary encompasses all of the project facilities and lands required for project 

operation and maintenance.

2.1.2 Project Safety

The York Haven Project has been operating for almost 110 years under past and 

current licenses (current license issued in 1980). The Muddy Run Project has been 

operating for almost 47 years under the existing license issued in 1964, and the 

Conowingo Project has been operating for almost 86 years under previous and the current

licenses (current license issued in 1980). During this time, Commission staff has 

conducted operational inspections focusing on the continued safety of the structures, 

identification of unauthorized modifications, efficiency and safety of operations, 

compliance with the terms of the licenses, and proper maintenance. The York Haven 

Project was exempted from the requirement to file Part 12 independent consultant safety 

inspection reports every 5 years. The Muddy Run and Conowingo projects have been 

inspected and evaluated every 5 years by an independent consultant, and a consultant’s 

safety report has been submitted for Commission review. As part of the relicensing 

process, the Commission staff would evaluate the continued adequacy of the proposed 

project facilities under new licenses. Special articles would be included in any license 

issued, as appropriate. Commission staff would continue to inspect the projects during 

the new license terms to assure continued adherence to Commission-approved plans and 

specifications, special license articles relating to construction (if any), operation and 

maintenance, and accepted engineering practices and procedures.

2.1.3 Existing Project Operation

2.1.3.1 York Haven Project

The York Haven Project is operated in a run-of-river mode and maintains a normal 

pool elevation of 277.86 feet under low to moderate flow conditions (<17,000 cfs). 

Under lower flow conditions, York Haven Power has the ability to draw down the 

impoundment by up to 1.10 feet, generally for purposes of dam maintenance. During 

periods of moderate to high flow conditions (>17,000 cfs), the project turbines cannot 

control water levels and the impoundment elevation varies above normal pool elevation 

depending upon river flow. Under these conditions, water overtops the main dam, east 

channel dam, and headrace walls when their crest elevations are exceeded. 

Flows required by the current license are discussed in section 2.1.4.1, Existing 

Environmental Measures, York Haven Project. A license requirement to maintain 
32

continuous flow is accomplished by maintaining at least two of the York Haven turbines 

operating at full gate providing approximately 1,000 to 1,500 cfs downstream and 

supplementing the turbine discharge with spill over the main dam spillway.

The York Haven powerhouse is manually operated at all times with two operators 

on duty during the day and one operator on duty at night. During normal operation, units 

are brought on-line based on anticipated flow rates given that the only available method 

of flow control at the project is through on/off operation of each of the 20 generating 

turbines. Project outflow adjustments typically occur in 700- to 1,100-cfs increments, up 

to the station hydraulic capacity. Historically, adjustments are made during the day-shift 

or at a shift change. Project operators ensure run-of-river operation through a series of 

checks and balances, monitoring operation and streamflow gage data, observing 

impoundment elevations, and applying project operational experience.

2.1.3.2 Muddy Run Project

The Muddy Run Project is a pumped storage hydroelectric facility. Water is

pumped from the lower reservoir (Conowingo Pond) to the upper reservoir which has

33,894 acre-feet of active storage available for pumped storage operation. Typically,

pumping occurs during low-load periods when energy costs are low, while generation 

occurs during high-load periods.

The Muddy Run Project is typically operated from control panels at the Muddy

Run powerhouse. The project, however, has automatic generation control equipment

capable of starting, running, and stopping the units. This equipment permits remote

operation of the plant in generation mode from the corporate office in Kennett Square,

Pennsylvania.

Operation of the Muddy Run Project is generally not affected by changes in 

hydrologic conditions when compared to conventional hydroelectric projects. Pumped

storage projects are typically considered to be closed systems, in that they maintain a

usable volume of water that is cycled between the upper and lower reservoirs without the 

need to store or use water flowing through the project from the upper reaches of the 

drainage basin. Given this, the operation of the Muddy Run Project depends upon

maintaining a specific total usable volume of water between the Muddy Run upper

r eservoir and Conowingo Pond, to limit effects on power production.

During mean flow years, flow issues do not typically arise at the project, as there

are sufficient flows to maintain the total usable volume of water for project operation and

to provide flows downstream of Conowingo dam. During a high-flow year, the project

also has sufficient water available to maintain the total usable volume in the system, 

while also passing higher levels of flow downstream.

However, during extreme high-flow events, project operation could be affected by 

having excess water in the system. Exelon typically adjusts Muddy Run operation to

reduce the levels in the upper reservoir prior to high Susquehanna River flow conditions. 

This allows the upper reservoir to be re-filled during high-flow periods and possibly 
33

reduce spill conditions at Conowingo dam. Extended periods of high-flow conditions

(potential spill situation at Conowingo dam) could reduce the generation at the Muddy

Run Project when Conowingo Pond is at or near full pond conditions, in order to reduce

spill over Conowingo dam.

During adverse water years, with limited inflow, the water management for the

project requires adjustments in the generation cycle. The most typical occurrence is a 

reduction in the total usable volume of water available for project operation. The extent

of the adjustments in flow and the volume of water retained in the Muddy Run upper

reservoir and Conowingo Pond depends upon the level of low flow experienced, as well

as the length of time of the adverse low-flow conditions. Maintaining the licensed 

Conowingo Pond levels and minimum flow requirements below Conowingo dam are the

primary factors affecting the total usable volume of water.

2.1.3.3 Conowingo Project

The Conowingo Project is a peaking hydroelectric facility that uses a limited active 

storage reservoir to generate during peak electricity demand periods. The project is typically 

operated semi-automatically as the generation setting (in MW) is programmed into the 

control system; however, turbines are brought on- line manually by an operator to ensure an 

efficient start-up until the generation setting is reached. At times, the project is also operated 

in either full manual or automatic mode, and this type of operation is typically dictated by the 

prevailing river flow and system load conditions. The current Conowingo Project license 

allows for the Conowingo Pond to fluctuate between elevation 101.2 feet and 110.2 feet. 

There are critical water levels associated with water withdrawals that influence reservoir 

levels in Conowingo Pond (see section 3.3.2, Water Resources, for details).

The current flow regime downstream of Conowingo dam is as follows:

Date Minimum Flow

March 1 - March 31

3,500 cfs or natural inflow (as measured at the U.S. 

Geological Survey [USGS] Marietta gage), 

whichever is less;

April 1 - April 30 10,000 cfs or natural inflow, whichever is less;

May 1 - May 31 7,500 cfs or natural inflow, whichever is less;

June 1 - September 14 5,000 cfs or natural inflow, whichever is less;

September 15 - November 30 3,500 cfs or natural inflow, whichever is less; and

December 1 - February 28 3,500 cfs intermittent (maximum 6 hours off 

followed by equal amount on).

The downstream discharge must equal these values or the discharge measured at 

the Susquehanna River at the Marietta U.S. Geological Survey (USGS) gage (No. 

01576000), whichever is less. The Marietta gage is located approximately 35 miles 
34

upstream of Conowingo dam above Safe Harbor dam. The gage is generally considered 

reflective of the lower Susquehanna River’s natural flow regime. During high electrical 

demand periods with low inflow Exelon uses water from the available Conowingo Pond 

storage (within its license constraints) to meet this demand. During non-peak periods of 

electrical demand, some combination of turbine units is used to provide the minimum 

flow requirements at the project. When inflows are below the minimum turbine capacity, 

any additional water needed to meet minimum flow requirements would be taken from 

storage.

During periods of regional drought and low river flow, Exelon has requested and 

received Commission approval for a temporary variance in the required minimum flow 

release from the Conowingo Project. As a result of a recent agreement with resource 

agencies, beginning in 2012, when the minimum flow variance is in effect, leakage flows 

(which total about 800 cfs) counts as approximately 580 cfs towards the minimum flow 

discharge at the Conowingo Project. The remaining portion of the project leakage 

(approximately 220 cfs) is credited to the PBAPS facility, as part of its consumptive use 

agreement. This temporary variance is typically approved by the Commission and the

resource agencies (i.e., SRBC, Maryland DNR, Pennsylvania FBC, and FWS), as well. 

The temporary variance allows Exelon to maintain an adequate pond level elevation and 

storage capacity throughout a low-flow period, not only for electric generating capacity, 

but also to ensure an adequate water supply is available for recreational interests and 

consumptive water usage on Conowingo Pond.

During high flow events, typically all units are operated at maximum wicket gate 

opening and crest gate operation is used to pass the remainder of the streamflow. Under 

such conditions, Conowingo Pond is usually kept near elevation 109.2 feet to prevent 

splashing of water onto the U.S. Route 1 roadway and debris from "floating over" the 

closed crest gates. There is a skimmer beam, bottom elevation 109.2 feet, that provides 

protection to motorists and prevents floating debris from going over the closed crest 

gates, whose top elevation is 110.2 feet.

2.1.4 Existing Environmental Measures

2.1.4.1 York Haven Project

Article 30 of the current FERC license requires York Haven Power to discharge a 

continuous minimum flow of 1,000 cfs from the powerhouse and an average daily flow 

of not less than 2,500 cfs, unless the inflow to the impoundment is less than these 

amounts, in which case the discharge from the project shall not be less than the inflow. 

These flows may be temporarily modified if required due to operating emergencies 

beyond the control of York Haven Power. 

The project includes a weir cut and vertical-slot fish ladder at the east channel 

dam, which became operational in 2000. When the east channel fish ladder is operated 

for the upstream migration of adult American shad (typically mid-April to mid-June), 

York Haven Power is required to spill 4,000 cfs at the main dam and to release 2,000 cfs 
35

at the east channel dam, which includes 67 cfs provided directly through the fish ladder. 

After the American shad upstream passage season and during the resident fish passage 

period, the project maintains a minimum flow of 400 cfs in the east channel until the 

seasonal closure of the fish ladder. Fish ladder closure occurs the earlier of December 15

or when average daily river water temperature is equal to or less than 40 degrees 

Fahrenheit (°F) for 3 consecutive days.

Downstream passage for adult and juvenile American shad is provided at the 

powerhouse by an operating protocol that includes: (1) when river flow is less than the 

project hydraulic capacity, prioritization of powerhouse generation through units 1 

through 6 (propeller units) on a first-on/last-off basis, followed by units 7 through 20 

(Francis units); (2) opening the forebay sluice gate located in the lower forebay corner 

adjacent to unit 1 for downstream fish passage; and (3) using temporary lighting above 

the forebay sluice gate to aid in attracting alosine species to the sluice gate exit.27 At 

river flow greater than project hydraulic capacity, which occurs about 60 percent of the 

time, downstream fish passage occurs via spillage over the dam.

York Haven Power owns and operates the following project recreation facilities: 

the Historic Canal Lock, East Shore Boat Launch, Goosehorn Island Picnic Area, Shelley 

Island Recreation Area, Goodling Island Picnic Area, Beshore Island Recreation Area, 

Battery Island Recreation Area, Cly Shore recreational lot sites, York Haven Power Plant 

Recreation Area, and Canoe Portage trail. In addition, York Haven Power implements a 

recreational lot permitting program to accommodate boating, fishing, and other day 

use activities.

2.1.4.2 Muddy Run Project

Prior to predicted high Susquehanna River flow events, Exelon typically 

voluntarily adjusts Muddy Run operation to reduce the levels in the upper reservoir. 

This allows the upper reservoir to be re-filled during high-flow periods and possibly 

reduce spill conditions at Conowingo dam. 

Exelon maintains three recreation areas at the project. The primary project 

recreation site is Muddy Run Park, a 700-acre park that includes day use areas, a 189-site 

campground, 100-acre Recreation Lake that abuts the upper reservoir, and a visitor 

information center. Immediately downstream of the powerhouse is Wissler’s Run Park, a 

day use area with parking for 130 vehicles. In addition, the project includes the 800-acre 

 

27 This downstream passage protocol was reported to the Commission by filing of 

a “Downstream Passage Report” on March 19, 2002. That report was required by 

Ordering Paragraph (C) of the Commission’s June 30, 1994, Order Approving Fish 

Passage Settlement Agreement, which was the agreement that led to the eventual 

construction of the east channel fish ladder. 
36

Muddy Run WMA, located on project and non-project land. Roads and trails within this 

area provide access for hunters, hikers, birders, and equestrians.

2.1.4.3 Conowingo Project

The current license allows Conowingo Pond to fluctuate between elevation 101.2 

and 110.2 feet, except on weekends between Memorial Day and Labor Day, when the 

elevation must be at or above 107.2 feet to meet recreational needs. However, other 

operating constraints (see section 3.3.2, Water Resources, for details) result in 

Conowingo Pond typically being maintained at or above elevation 109.2 feet. Pursuant 

to a Settlement Agreement approved by the Commission on January 24, 1989, Exelon 

operates the east and west fish lifts at Conowingo dam, and maintains seasonal minimum 

flows downstream of the dam ranging from 3,500 to 10,000 cfs, and described in more 

detail in section 2.1.3.3, Existing Project Operation, Conowingo Project. Article 37 of 

the current license includes provisions to protect cultural resources. 

Exelon currently enhances DO by a turbine venting system at units 1-7 and 

aerating runners at units 2 and 5. Downstream DO is continuously monitored by Exelon 

from May 1 through October 1. Exelon also removes floating and submerged debris 

from in front of the powerhouse intakes and sponsors community-based clean-ups at 

Conowingo Pond and downstream of Conowingo dam.

Exelon provides 16 project-related recreation facilities that include parks, day use 

areas, marinas, boat launches, and a visitor center: (1) Lock 13; (2) Lock 15; (3) Muddy 

Creek Boat Launch; (4) Cold Cabin Boat Launch; (5) Dorsey Park; (6) Line Bridge; 

(7) Broad Creek Public Landing; (8) Glen Cove Marina; (9) Conowingo Swimming Pool 

and Visitor’s Center; (10) Peach Bottom Marina; (11) Conowingo Creek Boat Launch; 

(12) Funk’s Pond; (13) Fisherman’s Park/Shures Landing; (14) Octoraro Creek Access; 

(15) 3.5 miles of the Mason-Dixon Trail; (16) and the Susquehanna State Park. 

2.2 APPLICANTS’ PROPOSALS

2.2.1 Proposed Project Facilities

York Haven Power proposes to construct a nature-like fishway28 at the north end 

of the York Haven Project main dam where it abuts Three Mile Island. Construction

would require modifications to the north end of the dam. No other modifications are 

proposed to project facilities. 

No modifications are proposed to project facilities at the Muddy Run Project.

 

28 A nature-like fishway is a fishway that is designed to appear and operate similar 

to a natural riffle, with a gradually sloping channel interspersed with rock weirs and 

pools. These fishways are typically suitable for a wide range of species.
37

Exelon proposes to construct an eel trap and transport facility on the west side of 

the Conowingo Project tailrace, and to construct a similar facility on the east side of the 

tailrace or in Octoraro Creek. No other modifications to project facilities are proposed at 

the Conowingo Project. 

2.2.2 Proposed Project Operation

In conjunction with the construction of the nature-like fishway, York Haven 

Power proposes to modify project flow releases to provide fish passage attraction flows 

to the nature-like fishway and to establish the nature-like fishway as the primary fish 

passage facility and the existing east channel fishway as the secondary passage facility. 

The proposed flow release changes would redistribute minimum flow releases among the 

various project flow release structures (east channel spillway, east channel fishway,

nature-like fishway, main dam, and powerhouse). The overall project minimum flow 

requirements downstream of the project would not change. The flow release changes are 

also discussed in section 2.2.3.1, Proposed Environmental Measures, York 

Haven Project.

No modifications to Muddy Run or Conowingo project operation are proposed.

2.2.3 Proposed Environmental Measures

2.2.3.1 York Haven Project

The Settlement Agreement resolves among the Settling Parties all issues

associated with issuance of a new license for the project regarding upstream passage of 

American shad and American eels, downstream passage of juvenile and post-spawning 

American shad, downstream passage of silver stage American eel, resident fish passage, 

flow management, water quality and debris management, and endangered species and 

species of special concern. We consider the Settlement Agreement to represent the 

proposed action regarding these issues for this project.29 For measures related to other 

environmental issues (i.e., recreation, land use, and cultural resources) we assume the 

proposed measures presented in the final license application continue to be proposed.

 

29 Our summary of the measures in the Settlement Agreement may differ from the 

specific language of the Settlement Agreement. Details of individual components of the 

measures listed in section 3.0 of the Settlement Agreement (measures that the parties 

agree should be incorporated in the terms of the license), including programmatic 

elements such as schedules for developing plans and details of monitoring, evaluation, 

and reporting, are not listed. Characterization of these measures is our attempt to provide

a concise summary of the measures for this draft EIS and is not intended to modify any of 

the terms of the Settlement Agreement. 
38

Under the terms of the Settlement Agreement, York Haven Power would continue 

the following existing environmental measures at the project (we indicate the designation 

of the measure in the Settlement Agreement in parenthesis):

• Provide a year-round, continuous, minimum flow from the project of 

1,000 cfs and an average daily minimum flow of 2,500 cfs, or inflow, 

whichever is less, to protect and enhance aquatic resources downstream of 

the project (measures 3.2.1[c][i], 3.2.1[c][ii],3.2.2[c][i], and 3.2.2[c][ii]).

• Operate the project in a run-of-river mode when inflow to the project is less 

than 3,000 cfs, without deliberate impoundment drawdown or storage for 

purposes of generating electricity in particular time periods (measures 

3.2.1[c][iii] and 3.2.2[c][iii]).

• Operate and maintain the existing east channel upstream fishway for 

upstream fish passage (measure 3.1.8[a]).

• Provide a minimum flow of 2,000 cfs at the east channel dam and a spillage 

flow of 4,000 cfs at the main dam during the American shad upstream 

passage season when the east channel fishway is in operation. The 

upstream passage season is determined by the Fish Passage Technical 

Advisory Committee but generally extends from mid-April through midJune (measures 3.2.1[a][i] and 3.2.1[a][ii]).

• After the American shad upstream passage season until the end of the 

resident fish passage season (the earlier of December 15 or until the 

average daily river temperature is < 40o

F, maintain a minimum flow of 400 

cfs in the east channel downstream from the east channel fishway during 

the period that the east channel fishway is operated to allow upstream 

passage of resident fish species, per the June 2010 Consent Order and 

Agreement between York Haven Power and Pennsylvania DEP (measures 

3.2.1[b][i] and 3.2.1[b][ii][1]). 

• Continue the current downstream juvenile American shad passage protocol, 

which calls for the operation of units 1-6 (Kaplan and propeller units) to be 

first online and last offline during the juvenile shad downstream migration 

period (which typically is from October 1 through November 30), and 

opening the forebay sluice gate at specific times for downstream fish 

passage. If river flows exceed the capacity of units 1-6, unit 14 would be 

operated, and if flows exceed the capacities of units 1-6 and 14, units 7-13 

and 15-30 would be operated in ascending order (measures 3.1.6[a][i], 

3.1.6[b][i], and 3.2.1[b][ii][2]).

• To prevent a buildup of debris that could affect project and fish passage 

operations, remove non-natural debris from the forebay and sluice 
39

remaining natural debris downstream after notifying the downstream PPL 

Brunner Island Station (measure 3.3 [b]).

• Contribute $25,000 per year to the York County Conservation District or 

such other entity identified by Pennsylvania DEP for the purposes of debris 

removal in the lower Susquehanna River watershed (measure 3.3[a]).

The Settlement Agreement includes provisions for York Haven Power to 

implement the following suite of measures designed to reallocate the existing minimum 

flows to facilitate migration of American shad and American eel:

• Pass about 370 cfs through the forebay sluice gate for 1 or 2 hours in the 

morning during weekdays if river flows exceed the sum of the turbine 

hydraulic capacity, flows through the nature-like fishway, once constructed, 

flows through the east channel, and flows (if any) over the main dam from 

May 1 through June 30 to facilitate downstream passage of post-spawning 

adult American shad, and during the juvenile American shad downstream 

passage period to facilitate downstream passage of juvenile American shad. 

• Pass about 370 cfs through the forebay sluice gate between the hours of 5 

and 11 p.m. during the entire juvenile American shad passage period to 

facilitate downstream passage of juvenile American shad (measures

3.1.6[a][ii] and 3.1.6[b][ii]).

• Develop designs within 4 years of license issuance for: (1) removal of 

obstructions in or deepening of the plunge pool below the forebay sluice 

gate, and (2) a chute structure to convey flows beyond the roadway on the 

downstream side of the cable alley structure to protect outmigrating 

juvenile and adult American shad that pass into the downstream plunge 

pool.

• Cooperate with resource agencies and other interested parties to conduct a 

lower Susquehanna River downstream eel migration study. This 

cooperation would include monitoring silver eels at the project and 

providing $25,000 to support the study (measures 3.1.7[b], 4.1.1[a], and 

4.1.2[a]).

• Conduct a site-specific silver eel route of passage study as described in 

appendix G of the Settlement Agreement including the potential for 

providing $50,000 to resource agencies for collection and tagging of silver 

eels at upstream locations (measures 3.1.7[c] and 4.1.1[b]).

• Conduct a site-specific silver eel survival study as described in appendix H 

of the Settlement Agreement (measure 3.1.7[c]).

• Conduct a downstream eel passage improvement study if downstream eel 

passage goals are not achieved with provisions for subsequent monitoring 

and adjustments (measures 3.1.7[e], 3.1.7[f], 3.1.7[g], and 3.1.7[h]). 
40

York Haven Power proposes to construct, operate, and maintain a nature-like 

fishway in the vicinity of the apex of the main dam and Three Mile Island in compliance 

with design criteria specified in appendix A of the Settlement Agreement (measures 3.1.1 

and 3.1.2). Prior to and upon completion of the nature-like fishway, York Haven Power 

proposes to implement the following measures:

• Develop an erosion and sediment control plan for construction of the 

nature-like fishway.

• Prior to construction of the nature-like fishway, conduct vegetation surveys, 

wetlands delineations, invasive species surveys, rare species surveys, bog 

turtle habitat assessments, and bald eagle surveys in the area of the naturelike fishway.

• Conduct American shad upstream passage effectiveness studies using radio 

telemetry beginning during the second year of nature-like fishway

operation. If the project area passage success criterion is not achieved, 

York Haven Power would implement corrective measures, followed by two 

additional years of radio telemetry studies to confirm achievement of the 

project area passage success criterion (measure 3.1.3).

• Conduct a juvenile American shad headrace turbine avoidance study 

consistent with design criteria included in appendix D of the Settlement 

Agreement (measure 3.1.6[d]).

• If the juvenile American shad headrace turbine avoidance goals are not 

achieved, implement measures that would enhance the effectiveness of 

downstream juvenile shad passage and conduct a supplemental juvenile 

American shad headrace turbine avoidance study within 2 years of 

implementing the measures. Provisions are made for subsequent measures 

and evaluations (measures 3.1.6[f], 3.1.6[g], and 3.1.6[h], and 3.1.6[i]).

• Provide an average daily minimum flow in the east channel below the east 

channel dam of 267 cfs year round to protect aquatic resources in the east 

channel and provide a minimum passage flow for fish ascending the east 

channel and using the east channel fishway (measures 3.2.2[a][i] and 

3.2.2[b][b][i]).

• Provide at least 5 percent of river flow through the nature-like fishway and 

supplemental attraction flow channels when flows entering the project 

during the American shad upstream passage season are between 5,000 and 

150,000 cfs. This would equate to a minimum flow through the nature-like 

fishway of between 1,000 and 7,500 cfs depending on inflow (measure 

3.2.2[a][ii]).
41

• Provide a minimum flow of 200 cfs through the nature-like fishway outside 

of the American shad upstream passage season when the river elevation is 

at the crest of the main dam (measures 3.1.6[b][iii] and 3.2.2[b][ii]). 

• To the extent controllable by York Haven Power, when flows exceed the 

hydraulic capacity of all available generating units, manage flows to 

maximize flow over the main dam and the nature-like fishway to provide 

attraction flow to the vicinity of and from the nature-like fishway to 

maximize fishway effectiveness (measure 3.2.2[b][iii]).

York Haven Power also proposes to implement the following additional 

environmental measures included in the final license application but not included in the 

Settlement Agreement: 

• Maintain existing recreation facilities on four islands in Lake Frederic and 

the recreation facilities at the powerhouse, including a portage trail for 

canoeists and fishing access along the downstream face of the powerhouse

and consult with the resource agencies on recreation resources and 

management strategies every 10 years after the effective date of any new 

license. 

• Continue the current permitting program for the approximately 300 

recreational lots located within the project boundary, but terminate permits 

and remove from the licensing program existing recreational lots upon 

abandonment by the lessee, or when existing structures become damaged 

and are not replaced by structures conforming to all applicable federal, 

state, and local regulations. 

• Implement the HPMP filed with the Commission on December 28, 2012, to 

manage project effects on historic properties eligible for listing on the 

National Register.

2.2.3.2 Muddy Run Project

Exelon proposes the following environmental measures at the project:

• Develop a DO monitoring plan no earlier than November 1, 2027, with 

measures designed to ensure that the project does not violate DO standards. 

• Develop FPOP for minimizing delay and potential fish entrainment during 

upstream and downstream fish passage past the project tailrace during 

generating and pumping cycles, with specific targets for upstream and 

downstream passage at the Muddy Run Project, and corrective actions if 

targets are not met.

• Develop a plan and schedule as part of the fish passage requirements for a 

radio telemetry study or equivalent Tier II study of American shad passage 

and behavior within the Muddy Run project boundary if resource agencies 
42

determine that operation of the Muddy Run Project is causing the Holtwood 

Project to fail to meet its Tier I upstream American shad target specified in 

the water quality certification for the Holtwood Project.

• Implement the American Eel Passage Plan30 filed with the license 

application for an eel trap and truck program to trap, hold, and transport 

American eels from the Conowingo Project and Octoraro Creek to 

designated points in the Susquehanna River watershed until at least 2030,

and then either continue the trap and truck program or construct a volitional 

eel passage facility at Conowingo dam.31

• Implement the Bald Eagle Management Plan filed with the license 

application providing for the management of bald eagle habitat on Exelon 

lands in accordance with recommendations from the National Bald Eagle 

Management Guidelines (FWS, 2007a) and state agency guidance. Bald 

eagle habitat, including nest sites, forage sites, and communal roost sites,

on Exelon lands would be managed through a range of measures that would 

be tailored to the types of activities with potential to affect eagles. These 

measures would include, but not be limited to, seasonal restrictions on 

maintenance activities such as herbicide applications during the breeding 

season, distance buffers, and landscape buffers.

• Implement the Bog Turtle Management Plan filed with the license 

application to minimize impacts to bog turtles and that includes: 

(1) restricting mowing in the wetland documented to support bog turtles; 

(2) controlling invasive and woody plants, particularly reed canary grass; 

and (3) limiting public access to the wetland without advertising the reason.

• Once every 10 years through the term of the license, evaluate all state and 

federal endangered and threatened species that may be present within the 

project boundary, and if the evaluation identified the presence, critical 

habitat, or critical dependence of endangered species, propose and 

implement a protection plan for each species. 

 

30 Exelon filed an Eel Management Plan with its final license application. In the

water quality certification for the Muddy Run Project, the Pennsylvania Department of 

Environmental Protection called this plan an American Eel Passage Plan, and we use this 

title throughout the EIS.

31 Exelon is proposing that a Muddy Run Project measure be implemented at the 

Conowingo Project, which is not under the same license. It is Commission policy that a 

condition for one license cannot be required and implemented at a different licensed 

project. 
43

• Provide annual grants up to $450,000 equally to the Lancaster County and 

York County Conservation Districts for the implementation of agricultural 

pasture and barnyard BMPs to control sediment loading to the 

Susquehanna River.

• Provide $50,000 annually to the Pennsylvania FBC to perform habitat 

improvement projects including removal of small dams. 

• Implement the Recreation Management Plan filed with the license 

application that includes measures for maintenance and capital 

improvements and contains specific enhancements at project 

recreation facilities.

At Muddy Run Park: (1) replace the Recreation Lake boat launching 

facility and boat dock with an improved launching ramp and Americans

with Disabilities Act (ADA)-compliant dock; (2) implement shoreline

erosion measures to improve runoff and stability in the vicinity of an ADAcompliant picnic area and boat rental dock; (3) replace an existing wood 

retaining wall with a sheet pile retaining wall to reduce shoreline erosion 

near the boat dock area; (4) upgrade the electric service to 50 campsites in 

the park, and monitor future need and upgrade additional sites when the 

demand occurs; (5) expand an existing playground area near the Visitor’s 

Center with safety swings and three modular play structures suitable for 

younger children (tot lots); and (6) install a mulch safety surface, and 

construct a 2,000 square foot water spray park near the park entrance, along 

with paving resurfacing. 

At Wissler’s Run Park: (1) complete the replacement of the picnic 

pavilion;

32 (2) designate and sign two additional ADA-compliant parking 

spaces near the picnic pavilion for compliance with standards set by ADA 

Accessibility Guidelines for Buildings and Facilities; and (3) remove the 

existing non-functioning fish cleaning station. 

At Muddy Run WMA: (1) continue to lease the Muddy Run WMA to the 

Pennsylvania Game Commission for the management of the Muddy Run 

WMA to provide hunting opportunities in the area; and (2) erect and 

maintain FERC Part 8 signs at the River Road and Furniss Road WMA 

parking areas to identify the conditions of access to the site.

• Implement the Shoreline Management Plan (SMP) filed with the license 

application and consistent with Guidance for Shoreline Management 

 

32 The walkway from the parking area to the picnic area and the parking lot were 

both repaved in 2011.
44

Planning at Hydropower Projects (FERC, 2001). The SMP includes 

specific measures and policies related to shoreline vegetation management 

and erosion control, woody debris management, game species management, 

sensitive natural resource protection, recreation use, and use of project 

lands and BMPs for controlling sediment introduction from lands within the 

project boundary. 

• Implement the osprey management policy described in Exelon’s proposed 

SMP. 

• Implement a cultural resources management plan if cultural materials are 

identified during project-related activities.

2.2.3.3 Conowingo Project

Exelon proposes to continue the following environmental measures at the project:

• Operate the project with a normal range of operation of Conowingo Pond 

between elevations 101.2 and 110.2 feet, with a minimum elevation of 

107.2 feet on weekends between Memorial Day and Labor Day, to meet 

recreational needs.

• Provide minimum flow releases from the project, as described below, or a 

minimum flow equal to the discharge (natural inflow) measured at the 

Marietta USGS gage (No. 01576000), whichever is less:

- March 1 – March 31: 3,500 cfs or natural inflow;

- April 1 – April 30: 10,000 cfs or natural inflow;

- May 1 – May 31: 7,500 cfs or natural inflow;

- June 1 – September 14: 5,000 cfs or natural inflow;

- September 15 – November 30: 3,500 cfs or natural inflow; and

- December 1 – February 28: 3,500 cfs intermittent (maximum 6 hours 

off followed by equal amount on).

• Enhance DO at the project using the turbine venting systems on Units 1

through 7 and the aerating runners on Units 2 and 5, and continuously 

monitor DO levels from May 1 through October 1 at the Station 643 

location about 0.6 mile downstream of Conowingo dam.

• Operate the east fish lift for upstream passage of American shad, river 

herring, and other migratory fishes, and the west fish lift for American shad 

egg collections and other research purposes.

• Manage debris to include clamming (with three gantry cranes with grapple 

attachments) to remove submerged debris from the area upstream of the 

powerhouse intakes and floating surficial debris in front of the powerhouse 
45

intakes, and the sponsorship of community-based clean-ups in the pond and 

downstream of the dam.

• Maintain the project’s public recreation facilities.

Exelon proposes the following new environmental measures at the project:

• Implement the Sediment Management Plan filed with the license 

application that identifies benchmarks and thresholds for action to address 

sediment issues that may affect project operation.

• Conduct a bathymetric survey of Conowingo Pond every 5 years to monitor 

sediment transport and depositional patterns within the pond.

• Implement a preventive maintenance program for the east fish lift that 

would extend the useful life of the facility over the next license term.

• Use the project turbines as the route for downstream passage of American 

shad and river herring, based on studies that show high survival for fish 

passing through the turbines.

• Construct a permanent trap and transport facility for upstream passage of 

American eel, consisting of an eel ramp and collection facility on the west 

and east banks of the Conowingo tailrace (an alternative east bank facility 

would be in Octoraro Creek).

• After 2030, construct volitional eel passage facilities on the west and east 

banks that consist of full eel ramps with resting pools.

• Participate in a trap and transport program for downstream eel passage, in 

cooperation with the other hydroelectric project operators on the lower 

Susquehanna River to trap and transport adult American eels from smaller 

tributaries upstream of York Haven dam to below Conowingo dam.

• Implement the final Bald Eagle Management Plan filed with the license 

application providing for the management of bald eagle habitat on Exelon 

lands in accordance with recommendations from the National Bald Eagle 

Management Guidelines (FWS, 2007a) and state agency guidance. Bald 

eagle habitat, including nest sites, forage sites, and communal roost sites,

on Exelon lands would be managed through a range of measures that would 

be tailored to the types of activities with potential to affect eagles. These 

measures would include, but not be limited to, seasonal restrictions on

maintenance activities such as herbicide applications during breeding 

season, distance buffers, and landscape buffers.

• Implement the Recreation Management Plan filed with license application

to guide the operation and maintenance of Exelon’s recreation facilities and 

the implementation of recreation facility enhancements as outlined above. 
46

• Implement improvements to project recreation facilities as follows:

Recreational Facility Summary of Capital Improvements

Lock 13 Install a trailhead directional sign at the Lock 12 

parking area (access to Lock 13 is from Lock 12, a 

facility owned by Holtwood-PPL), and clear 

vegetation from within the lock to provide an 

unobstructed view of the structure; construct light 

fencing on each side of the lock structure to protect 

visitors

Lock 15 Designate two ADA-compliant parking spaces in the 

existing parking area and install a dock on the 

shoreline near the picnic area to allow boaters to 

access the site; construct a concrete pad for portable 

restroom placement; stabilize the open shoreline area 

near the parking area to prevent erosion

Muddy Creek boat 

launch

Designate two boat trailer spaces and one vehicle 

space for ADA-compliant parking in the existing 

parking lot; stabilize areas adjacent to the southwest 

corner and southerly side of the parking area to 

improve drainage and redirect flow away from the 

parking area and the river; install a sign providing 

information on the Conowingo dam canoe portage and 

the location of the portage take-out 

Cold Cabin boat 

launch

Improve access by designating a one-way directional 

traffic pattern through the site and constructing 

parking for 11 vehicles (five boat trailer and six 

vehicle spaces), including two ADA-compliant

spaces; reinforce existing boat ramp to prevent 

undermining of the ramp and install a boat dock; 

install a sign providing information on the Conowingo 

dam canoe portage and the location of the portage 

take-out; provide two ADA-compliant picnic tables; 

install a concrete pad for the placement of two 

portable restrooms (one ADA-compliant, one

standard)

Dorsey Park Rebuild both boat ramps at Dorsey Park; designate 

one ADA-compliant boat trailer space and one 

ADA-compliant vehicle space in the existing lot; 

install a concrete pad for three portable restrooms 

(one ADA-compliant, two standard); install a sign 
47

Recreational Facility Summary of Capital Improvements

providing information on the Conowingo dam canoe 

portage and the location of the portage take-out

Conowingo Creek 

boat launch

Designate one ADA-compliant parking space in the 

existing parking area; stabilize a roadside ditch along 

Mt. Zoar Road and construct a stone-lined drainage 

ditch along the south side of the parking lot to redirect 

runoff from the parking lot and boat ramp; install a 

sign providing information on the Conowingo dam 

canoe portage and the location of the portage take-out

Glen Cove Marina Expand parking at the marina by adding seven 

additional boat trailer spaces (one ADA-compliant) 

and 11 vehicle (two ADA-compliant) spaces; repair 

the marina’s bulkhead wall

Funk’s Pond Designate one ADA-compliant parking space in the 

existing parking area

Line Bridge Perform shoreline erosion control and stabilization 

work at this unimproved carry-in boat access area

Conowingo swimming 

pool

Install an ADA-compliant access facility at the 

swimming pool and an ADA-compliant access ramp 

at the wading pool

Conowingo dam 

overlook

Reopen the facility and designate three 

ADA-compliant vehicle spaces in the existing parking

lot; demolish the existing pavilion and replace it with 

a new 24-foot by 24-foot wooden pavilion; remove 

pavement from the easterly corner of the existing 

paved parking area, loam and seed, and install three 

ADA-compliant pathways and picnic tables; install 

security fencing around the site to restrict access to 

Conowingo dam, while allowing unobstructed views 

from the pavilion and picnic area

Fisherman’s Park and 

Shures Landing

Widen the access road to the facility by 3 to 5 feet to 

allow construction of 12-foot wide lanes; construct a 

retaining wall along the easterly 250 feet of the 

existing parking area along the access road; designate 

five additional ADA-compliant parking spaces in the 

existing parking lot; widen the access road leading to 

Shures Landing by 4 feet along the eastbound lane for 

320 feet, and widen the access road from the trailhead 
48

Recreational Facility Summary of Capital Improvements

parking northerly to the retaining wall by 2 feet; 

construct an additional 13-space parking area near the 

Lower Susquehanna Heritage Greenway trailhead at 

the southerly end of Fisherman’s Park; demolish the 

existing hard surface boat launch and asphalt access at 

Shures Landing and place stone fill next to the 

existing wall down to existing grade along the 

Susquehanna River shoreline; construct a new 20-foot 

wide hard surface carry-in boat launch with a floating 

dock and breakwater at Shures Landing, to replace the 

existing launch area

Peach Bottom access Construct a small (approximately four vehicle) roadside parking area near the existing informal boat 

launch area south of Peters Creek; install a sign 

providing information on Conowingo dam canoe 

portage and the location of the portage take-out

• Implement the SMP filed with the license application that includes specific 

measures and policies related to shoreline vegetation management and 

erosion control, woody debris management, game species management, 

sensitive natural resource protection, recreation use, BMPs for controlling 

sediment introduction from lands within the project boundary, and use of 

project lands. 

• Implement the osprey management policy described in Exelon’s 

proposed SMP.

• Implement the HPMP filed with the license application for the management 

of archaeological and historic resources throughout the term of any new 

license, including: (1) a schedule and methodology for completing any 

additional recommended studies and implementing monitoring measures; 

(2) management measures for identified historic properties including 

Conowingo dam and powerhouse; (3) protection of any historic properties 

threatened by project-related activities, including project operation, 

shoreline and aquatic recreation, shoreline development, routine project 

maintenance, and other project activities or operations; and (4) public 

outreach, education, and signage for the purpose of reducing looting and 

vandalism of sites.

Project Boundary Revisions

York Haven Power proposes to add 1.9 acres to the total York Haven Project

boundary acreage to encompass the project’s East Shore Boat Launch and Canal Lock 

recreation area. 
49

Exelon proposes to modify the Conowingo Project boundary by removing lands 

that are not necessary for operation and maintenance of the Conowingo Project or for 

other specified project purposes, such as public recreation or protection of environmental 

resources. These lands include: 0.06 acre of land not owned by Exelon in the upper 

reaches of Conowingo Pond; 34.4 acres along the Susquehanna River shoreline at the 

Muddy Run Project (to minimize the overlap of project lands between the two projects); 

205.6 acres on upper Broad Creek, a tributary to Conowingo Pond; and 1,758.7 acres of 

the Susquehanna River and shoreline downstream of Conowingo dam. This modification 

would remove lands from upper Broad Creek and from the Susquehanna River 

downstream of Rowland Island that were originally included for construction of the 

project. The proposed project boundary for the Conowingo Project would contain 9,919 

acres, including 8,850 acres of project waters and 1,069 acres of land above the normal 

high water elevation in Lancaster and York counties, Pennsylvania, and Harford and 

Cecil counties, Maryland. Exelon would negotiate leases with existing recreation facility 

operators for the continued operation of those facilities located on lands owned by 

Exelon, but no longer within the project boundary. Exelon would also negotiate a new 

lease with Maryland DNR for the continued protection and use of the collocated Lower 

Susquehanna Greenway Trail and Mason-Dixon Trail on Exelon-owned lands outside of 

the project boundary. The existing lease expires in August 2014.

2.2.4 Modifications to the Applicants’ Proposals – Mandatory Conditions 

The following preliminary mandatory conditions have been provided and are 

evaluated in this document. In this draft EIS, we do not analyze a staff alternative with 

mandatory conditions (composite alternative) because the section 18 prescriptions are 

preliminary and the Commission has only received a final section 401 certification for the 

Muddy Run Project. If we receive final prescriptions and certifications for all three 

projects, we may include a composite alternative in the final EIS.

Section 18 Prescriptions

York Haven Project

Interior’s section 18 preliminary prescription specifies:

• A reservation of authority to prescribe fishways during the term of the

license.

• Design populations for American shad, river herring, and American eel.

• Operational flows at the project that are the same as provided in the 

Settlement Agreement as described above.

• An operational schedule for upstream and downstream fish passage 

facilities.

• Fishway operating procedures for each fishway.
50

• Construction of a nature-like fishway at the apex of the main dam by 

November 30, 2012.

• Required monitoring and effectiveness studies for the nature-like fishway, 

to ensure that at least 75 percent of the shad passed at the downstream Safe 

Harbor Project be passed at the York Haven Project, or that at least 85 

percent of the shad that arrive in the York Haven Project area be passed

above the York Haven Project.

• Criteria for determining if required effectiveness is met, and measures to be 

implemented if effectiveness is not met.

• That the upstream end of the nature-like fishway be designed to 

accommodate installation of Passive Integrated Transponder (PIT) tag 

monitoring devices at such time that PIT tag monitoring devices become 

available and feasible for reliably monitoring American shad exiting the 

nature-like fishway.

Muddy Run Project

Interior’s section 18 preliminary prescription specifies:

• A reservation of authority to prescribe fishways during the term of the

license.

33

• FPOP to describe Muddy Run Project operation during the fish passage 

season, including regular maintenance activities and emergency procedures 

to allow safe, timely, and effective fish passage past the Muddy Run 

Project. 

• A fish passage monitoring plan (FPMP), including an American shad 

passage monitoring plan, for post-FPOP implementation monitoring, and 

the criteria for success consistent with the goals and objectives set forth in 

the Susquehanna River Anadromous Fish Restoration Plan.

• An eel passage program with other licensees on the river, so that Muddy 

Run operation does not interfere with passage objectives at the upstream 

Holtwood Project. 

• An American Eel Passage Plan at the project, including an eel trap and 

transport program from the downstream Conowingo Project to upstream 

locations, with design plans due to FERC within 1 year of license issuance.

• Financial support to FWS of $20,000/year for its eel trapping facility at 

Conowingo dam until the Muddy Run facility is completed.

 

33 NMFS also specifies a Reservation of Authority to later prescribe fishways.
51

• Field testing to determine the best locations for eel traps for upstream 

passage of elvers, prior to construction of permanent traps that would

consist of two ramp-style traps with the capacity to capture 50,000 eels/day, 

along with facilities for holding and transport, and a quality 

assurance/quality control program to ensure target survival of 95 percent.

• Instream evaluation of the presence of eels in the river and tributaries every 

3 years, and a 2-year downstream passage study of silver eels within 3 

years of license issuance.

Conowingo Project

Interior’s section 18 preliminary prescription specifies:

• A reservation of authority to prescribe fishways during the term of the 

license.

34

• Construction of upstream eel passage facilities (trap and trucking) near the 

west fish lift and on the east side of the tailrace, or in Octoraro Creek, to be 

operated until 2029, transitioning to volitional passage in 2030.

• Post-construction efficiency testing for all fish facilities and efficiency 

testing for downstream juvenile shad and adult eel passage.

• Alternative G of the preliminary prescription in three phases as described 

below.

• Phase I: Construct a new west fish lift for both trap and trucking and direct 

volitional upstream shad passage (two 6,500-gallon hoppers), with an 

auxiliary water system of 2,600 cfs. The objective would be to truck 

50,000 adult shad per year. Create a 5,000-foot-long zone of passage on 

the east and west shores of the tailrace below the dam. Implement a 

maximum downramping rate of 20,000 cfs/hour. Make channel 

modifications downstream to eliminate stranding in the spillway channel.

• Phase II: Modify the east fish lift stilling basin to allow a 900-cfs attraction 

flow, as originally designed. Relocate east fish lift entrance A to upstream 

of the Kaplan unit boils. Construct new entrance D and collection gallery 

to the east fish lift along the Kaplan units and connect to a new second 

hopper. Reconstruct entrance B to east fish lift at 45 degrees to the river 

flow as shown in figure 3-15.

• Phase III: If passage efficiency is not met in Phase I and II, make daily 

adjustments to minimum flows and turbine operation, construct an east fish 

 

34 NMFS also specifies a reservation of authority to later prescribe fishways.
52

lift auxiliary water supply of 4,325 cfs, and upgrade east fish lift equipment 

to allow a 15-minute cycle time. 

Water Quality Certification Conditions

Pennsylvania DEP issued a draft certification for public comment for the Muddy 

Run Project. In its reply comments filed on March 18, 2014, Exelon requested the 

Commission incorporate the conditions in the draft certification in its licensing proposal. 

Pennsylvania DEP issued final certification on June 3, 2014, and filed the final 

certification with the Commission on June 9, 2014. While Exelon has not indicated the 

final certification represents its proposal, our review of the draft and final certifications 

found that they are nearly identical; therefore, we include these measures in the list of 

Exelon’s proposed measures in section 2.2.3.2, Proposed Environmental Measures, 

Muddy Run Project, and identify them in the discussions in the resource sections to 

which they apply.

2.3 STAFF ALTERNATIVE

York Haven Project

Under the staff alternative, the project would include most of York Haven Power’s 

proposed measures as outlined in section 2.2.3.1, Proposed Environmental Measures, 

York Haven Project, above, with the following additions and modifications: 

• Develop a recreation management plan that provides for York Haven’s 

proposed maintenance of its existing recreation facilities with additional 

provisions to update the plan every 12 years consistent with every other 

Form 80 reporting period deadline, include safety measures during 

construction of the nature-like fishway, continue the licensing program for 

approximately 300 recreational lots within the project boundary, and 

implement revisions to the program to allow for the termination of permits 

and removal of lots from the program if structures are abandoned by the 

lessee, or when existing structures become damaged and are not replaced 

by conforming structures.

• Develop an SMP that includes specific measures and policies related to 

shoreline management at the project and include a provision to update the 

plan every 10 years. 

• Modify the proposed HPMP to add: (a) a requirement to request landowner 

permission to access sites on private lands within the project boundary and 

evaluate them for listing on the National Register and for project impacts if 

project impacts are identified during monitoring activities; (b) a plan and 

schedule to evaluate archaeological sites on York Haven lands within the 

project boundary for their National Register eligibility to ensure that any 

effects on sites owned by York Haven Power are fully considered in 

accordance with section 106; and (c) inclusion of two additional sites 
53

(36YO300, 36YO334) in the monitoring schedule, or clarification 

regarding why they were excluded.

Muddy Run Project

Under the staff alternative, the project would include most of Exelon’s proposed 

measures as outlined above with the following additions and modifications:

• Visit FWS’ Chesapeake Bay Field Office and the Pennsylvania Field Office 

websites prior to any ground disturbance and follow the bog turtle and bald 

eagle guidelines. 

• Modify Exelon’s proposed Recreation Management Plan to include 

recreation use monitoring and plan updates every 12 years in concert with

every other Form 80 reporting deadline.

• Modify Exelon’s proposed SMP to include a provision to update the plan 

every 10 years. 

• Develop an HPMP that provides for the management of historic properties 

and unevaluated cultural resources within the project APE and includes: 

(a) a detailed discussion of the three sites (36LA67, 36LA103, 36LA368) 

identified during the Phase IA cultural resources survey and two additional 

sites (36LA70, 36LA47) located outside of the project boundary; 

(b) requirements for National Register evaluation of affected sites in 

consultation with the Pennsylvania SHPO; (c) requirements for formal 

National Register evaluation of the Muddy Run Project; and 

(d) documentation of consultation with Indian Tribes. 

Conowingo Project 

Under the staff alternative, the project would include most of Exelon’s proposed 

measures as outlined above, with the addition of a modified minimum flow regime that 

would enhance current Exelon minimum flows from December through February and in 

the first 2 weeks of June.35 The following measures would also be included:

• Modify Exelon’s proposed Sediment Management Plan to include periodic 

dredging at the Conowingo Creek, Peters Creek (Peach Bottom Marina), 

and Broad Creek boat ramps, where sediments have been accumulating, to 

improve and maintain recreational boating access; and include with the 

 

35 Under the staff alternative, Exelon would be required to provide a continuous 

minimum flow of 3,500 cfs from September 15 to March 31, eliminating periods of no 

minimum flow in December through February, and a minimum flow of 7,500 cfs from 

June 1 to 15, an increase from the current minimum flow of 5,000 cfs during that period.
54

results of each bathymetric survey an analysis of any change in sediment 

deposition or scour in the pond from the previous survey(s). 

• Modify Exelon’s proposed minimum flow regime to enhance minimum 

flows from December through February, by eliminating periods with no 

minimum flow, and by increasing the minimum flow during the first 2 

weeks of June, summarized as follows: 

− September 15 – March 31: 3,500 cfs or natural inflow (as measured at 

the USGS Marietta gage No. 0157600), whichever is less;

− April 1 – April 30: 10,000 cfs or natural inflow, whichever is less;

− May 1 – June 15: 7,500 cfs or natural flow, whichever is less; and

− June 16 – September 14: 5,000 cfs or natural inflow, whichever is less. 

• Implement measures designed to improve upstream fish passage through 

modification to the existing west and east fish lifts that would include: 

(a) replacing the existing hopper at the west fish lift with a 1,500 gallon 

hopper; (b) improving the west fish lift sorting and loading process to 

facilitate trap and truck operations and implementing a trap and truck 

program for American shad; (c) conducting a feasibility study to determine 

engineering feasibility, potential fish passage benefits, and costs for 

additional attraction flow at the west fish lift and if determined feasible and 

beneficial, install additional flow capacity; (d) restoring the attraction flow 

in the east fish lift to its original design capacity of 900 cfs; (e) adding a 

second 3,300-gallon hopper to the east fish lift in the space provided for in 

the original design, and upgrading the electrical and mechanical equipment 

to allow for a 15-minute lift cycle; and (f) conducting a feasibility study for 

modifying the locations of entrances A and B if 2 years of effectiveness 

studies, after restoration of the 900-cfs attraction flow, show poor attraction 

at the east fish lift, and make the necessary modifications if feasible. 

• Modify Exelon’s proposed Bald Eagle Management Plan to include 

measures to minimize recreation-related disturbance in proximity to 

roosting or foraging eagles.

• Develop a northern map turtle protection plan to minimize project impacts 

to map turtles through monitoring, habitat management, and nest 

site protection.

• Develop a waterfowl nesting protection plan to identify waterfowl nesting 

habitat that is routinely flooded during the breeding season, and where 

feasible, establish mitigation measures to minimize impacts to 

waterfowl nests.
55

• Modify Exelon’s proposed Recreation Management Plan to include 

recreation use monitoring and plan updates every 12 years in concert with 

every other the Form 80 reporting deadline and a plan to provide angler 

access to the catwalk on a limited basis with security measures in place that 

address the vulnerability of the facility and the safety of the users of 

the catwalk. 

• Modify Exelon’s proposed SMP with the addition of a provision to update

the plan every 10 years.

• Modify Exelon’s proposed HPMP to include the following additional

provisions: (a) a revised APE with the narrow strip of land in the current 

project boundary extending downstream from Spencer Island along the west 

side of the river to Havre de Grace, Maryland; (b) a discussion of all 48 sites 

and 27 historic structures identified to date within the project APE or an 

explanation of why they are not considered; (c) correction to identify the 

Susquehanna and Tidewater Canal and Columbia & Port Deposit Railroad 

eligible for listing; (d) requirements to inventory any lands within the revised 

APE, evaluate identified cultural resources for eligibility, and address 

potential effects before sale or transfer of those lands; (e) a requirement to 

make good faith effort to obtain access to private property to conduct studies 

if project effects on cultural resources on private lands are identified; (f) a 

revised list of project activities involving the Conowingo Project that can be 

completed without Maryland SHPO review; (g) a process for assessing 

project-related ground-disturbing activities to determine whether or not 

archaeological sites would be affected, particularly in areas that have not had 

archaeological surveys; (h) requirements to ensure confidentiality of cultural 

resources location information during implementation of public outreach 

programs; and (i) a description of project-related activities that would require 

consultation with the Delaware Nation and the Onondaga Nation in 

accordance with section 106 of the NHPA and documentation of Native 

American consultation. 

Under the no-action alternative, each project would continue to operate under the 

terms and conditions of the existing licenses, and no new environmental protection, 

mitigation, or enhancement measures would be implemented. 

2.4 ALTERNATIVES CONSIDERED BUT ELIMINATED FROM DETAILED 

ANALYSIS

We considered several alternatives to the applicants’ proposals, but eliminated 

them from further analysis because they are not reasonable in the circumstances of this 

case. They are: (1) issuing non-power licenses, (2) federal takeover, and (3) retiring one 

or more of the projects.
56

2.4.1 Issuing a Non-Power License

A non-power license is a temporary license that the Commission will terminate 

when it determines that another governmental agency will assume regulatory authority 

and supervision over the lands and facilities covered by the non-power license. At this 

point, no agency has suggested a willingness or ability to takeover any of the three 

projects. No party has sought a non-power license and we have no basis for concluding 

that any of the Susquehanna River Projects should no longer be used to produce power. 

Thus, we do not consider issuing a non-power license a realistic alternative to relicensing 

in this circumstance.

2.4.2 Federal Government Takeover of the Projects

We do not consider federal takeover to be a reasonable alternative. Federal 

takeover and operation of any of the projects would require Congressional approval. 

Although that fact alone would not preclude further consideration of this alternative, 

there is no evidence to indicate that federal takeover should be recommended to 

Congress. No party has suggested federal takeover would be appropriate, and no federal 

agency has expressed an interest in operating any of the three projects.

2.4.3 Retiring the Project

Project retirement could be accomplished with or without dam removal. Either 

alterative would involve denial of the relicense application and surrender or termination 

of the existing license with appropriate conditions. No participant has suggested that dam 

removal at any of the projects would be appropriate in this case, and we have no basis for 

recommending it. Energy currently generated at the projects by a renewable resource 

would be lost. In addition, the project reservoirs are a major source of water supply for 

the region and support significant recreational activities, regardless of whether power is 

produced. Thus, dam removal is not a reasonable alternative to relicensing the projects

with appropriate protection, mitigation, and enhancement measures. 

The second project retirement alternative would involve retaining the dam and 

disabling or removing equipment used to generate power. Project works would remain in 

place and could be used for historic or other purposes. This would require us to identify 

another government agency with authority to assume regulatory control and supervision 

of the remaining facilities. No agency has stepped forward, and no participant has 

advocated this alternative. Nor have we any basis for recommending it. Furthermore, 

because the power supplied by the projects is needed, a source of replacement power 

would have to be identified. In these circumstances, we do not consider removal of the 

electric generating equipment at any of the projects to be a reasonable alternative.
57

3.0 ENVIRONMENTAL EFFECTS

In this section, we first describe the general environmental setting in the project 

vicinity and any environmental resources that could be cumulatively affected by 

relicensing the Susquehanna River Projects. Then, we address each affected 

environmental resource. For each resource, we first describe the affected environment—

the existing condition and the baseline against which to measure the effects of the 

proposed project and any alternative actions—and then the environmental effects of the 

proposed projects, including the proposed measures discussed in section 2.2.3, Proposed 

Environmental Measures. Unless otherwise identified, the sources of our information are 

the license applications for the projects (York Haven Power, 2012a; Exelon, 2012a and 

2012b) and the Settlement Agreement (January 30, 2014). We provide citations for 

information obtained from other sources. Staff conclusions and recommended measures 

are discussed in section 5.1, Comprehensive Development and Recommended Alternative. 

3.1 GENERAL DESCRIPTION OF THE RIVER BASIN

The Susquehanna River originates near Cooperstown, New York, at Otsego Lake,

and flows for about 444 miles to the Chesapeake Bay at Havre de Grace, Maryland 

(SRBC, 2008a). The drainage area of the Susquehanna River encompasses portions of 

New York, Pennsylvania, and Maryland and covers 27,510 square miles. The 

Susquehanna River Basin can be divided into six major subbasins: the Upper 

Susquehanna, Chemung, West Branch Susquehanna, Middle Susquehanna, Juniata, and 

Lower Susquehanna (see figure 1-1). 

The Susquehanna River Projects are located in the Lower Susquehanna River

subbasin. The lower Susquehanna River subbasin contains ridges spanning southwest to 

northeast and valleys of moderate width. The river cuts through these ridges in a 

perpendicular direction and widens as it flows south to southeast through hills and 

valleys. The southern portion of the Lower Susquehanna River subbasin consists of 

carved deep gorges in the narrowing river valley, and it is the most developed and suited 

for hydropower development because of the steep river slope.

The York Haven Project is located at RM 55 on the mainstem of the Susquehanna 

River, about 17 miles downstream from the city of Harrisburg, Pennsylvania. The upper 

reservoir of the Muddy Run Project is located on Muddy Run, a tributary (at RM 22) of 

the Susquehanna River, and the drainage area above the Muddy Run dam is 
58

9.2 square miles. The Muddy Run Project uses Conowingo Pond as its lower reservoir. 

The Conowingo Project is at RM 10 of the Susquehanna River, in Maryland.36

The major tributaries to the Lower Susquehanna River subbasin are the Conestoga

River and Conodoguinet, Swatara, Conewago, and Penn’s creeks (see figures 2-1, 2-2, 

and 2-3). Muddy Creek is a major tributary to Conowingo Pond. Smaller named 

tributaries to Conowingo Pond include Conowingo Creek, Broad Creek, Hanes Branch, 

Michaels Run, Peters Creek, Barnes Run, Fishing Creek, Wissler’s Run, and Muddy Run. 

Numerous unnamed tributaries also discharge to Conowingo Pond. The major tributaries 

of the Conowingo Project below Conowingo dam are Octoraro Creek and Deer Creek.

Climatic conditions vary within the Lower Susquehanna River subbasin. The 

Ridge and Valley physiographic province in the northwest part of the subbasin 

experiences a humid continental climate with large seasonal temperature variations. This

contrasts to the more coastal-type climate experienced in the Piedmont physiographic 

province in the southeastern part of the subbasin where temperatures are more moderate 

and precipitation is slightly greater. The average annual precipitation in the Susquehanna 

River Basin is 39.15 inches per year and is distributed fairly evenly throughout the year; 

however, long-term records indicate wet and dry periods, and droughts have been fairly 

common, at times threatening groundwater supplies. During the 1990s through the mid2000s, droughts have occurred in 8 of 16 years (SRBC, 2013). The annual average 

temperature ranges from 53°F at the Maryland-Pennsylvania border to 45°F in the upper 

Susquehanna River Basin.

3.2 CUMULATIVELY AFFECTED RESOURCES

According to the Council on Environmental Quality's regulations for 

implementing the National Environmental Policy Act (50 CFR §1508.7), an action may 

cause cumulative impacts on the environment if its impacts overlap in space or time with 

the impacts of other past, present, and reasonably foreseeable future actions, regardless of 

what agency or person undertakes such other actions. Cumulative effects can result from 

individually minor, but collectively significant, actions taking place over a period of time, 

including hydropower and other land and water development activities.

Based on information in the license applications, agency comments, other filings 

related to the projects, and preliminary staff analysis, we identified the following 

resources that have the potential, in combination with other activities, to be cumulatively 

 

36 The Safe Harbor Project (FERC No. 1025) and the Holtwood Project (FERC 

No. 1881) are located downstream of the York Haven Project at RM 32.2 and RM 24.6, 

respectively. The licenses for these two projects expire on April 22, 2030 (Safe Harbor), 

and August 31, 2030 (Holtwood). Table 3-1 contains further information about these 

two projects. 
59

affected by the continued operation of the Susquehanna River Projects: water quantity, 

water quality, migratory fisheries, and Chesapeake Bay habitat. We chose these 

resources because operation of the York Haven, Muddy Run, and Conowingo projects, in 

combination with other hydroelectric projects on the river, regulate river flows and in 

turn may affect water quality. In addition, along with the other hydroelectric projects on 

the river, all three projects affect migratory fish migration throughout the lower 

Susquehanna River. All four mainstem dams (York Haven, Safe Harbor, Holtwood, and 

Conowingo) have fish passage facilities, but each one provides a different level of 

effectiveness. Finally, flow regulation from Conowingo and the other hydroelectric

projects affects aquatic habitat downstream to the upper Chesapeake Bay.

3.2.1 Geographic Scope

The geographic scope of the analysis defines the physical limits or boundaries of 

the proposed action’s effects on the resources. Because the proposed action would affect 

resources differently, the geographic scope for each resource may vary. For the four 

identified resources, we identified the geographic scope as extending from Harrisburg, 

Pennsylvania, located upstream of the York Haven Project, downstream to the mouth of 

the Susquehanna River at Chesapeake Bay. We chose the above geographic bounds 

because the effects of proposed project operation and potential environmental measures 

on the identified resources, in combination with other activities in the basin, are limited to 

these areas. Flows and water quality are not affected by the York Haven Project, in 

concert with other water uses, once upstream of the influence of the York Haven 

reservoir. Migratory fishes are affected by the five lower river hydroelectric projects 

(including Muddy Run Project), but once migratory fishes reach upstream of the 

influence of the York Haven reservoir, any effects experienced from other dams on the 

river (low head, non-hydroelectric dams are located at Harrisburg and farther upstream in 

Sunbury, Pennsylvania) are unrelated to lower river hydroelectric operation. Upper 

Chesapeake Bay habitat may be affected by operation of the lower river projects, but 

those effects generally do not extend downstream of the mouth of the river. The river 

becomes tidal about 5 miles downstream of the dam, and an additional 5 miles of tidal 

river from this point to the mouth of the river tends to dampen any effects of the projects.

3.2.2 Temporal Scope

The temporal scope of our cumulative analysis in the EIS will include a discussion 

of past, present, and future actions and their effects on each resource that could be 

cumulatively affected. Based on the terms of the new licenses, the temporal scope will 

look 30 to 50 years into the future, concentrating on the effects on the resources from 

reasonably foreseeable future actions. The historical discussion will, by necessity, be 

limited by the amount of available information for each resource.
60

3.3 PROPOSED ACTION AND ACTION ALTERNATIVES

This section outlines the proposed action and the action alternatives with regard to: 

(1) geology and soils, (2) water resources, (3) terrestrial resources, (4) threatened and 

endangered species, (5) recreation and land use, (6) cultural resources, (7) aesthetics, and 

(8) socioeconomics. 

3.3.1 Geology and Soils

3.3.1.1 Affected Environment

Geology

The Susquehanna River Basin is located within the Appalachian Highlands 

physiographic region, and the Susquehanna River Projects are located within the 

Piedmont Province of this region, which is dominated by rolling lowlands, broad 

highlands, and ridges. Rock types consist predominantly of red shale, siltstone, 

sandstone, and some conglomerate that formed in the Jurassic and Triassic periods. 

Upland terraces of river-transported material occur at various elevations above the 

present river channel.

The York Haven Project is located within the Gettysburg-Newark Lowland 

Section within the Piedmont Province. The project’s main dam is bounded by diabase, a 

hard igneous rock. The geology of the remaining project area consists mostly of shale. 

Both the Muddy Run and Conowingo projects are within the Piedmont Upland 

Section of the Piedmont Province and are underlain by igneous and metamorphic rocks. 

The bedrock islands along the Susquehanna River below Holtwood dam (known as the 

Holtwood Gorge) are recognized as an outstanding geologic feature of Pennsylvania. 

Specifically, the Pennsylvania Department of Conservation and Natural Resources 

(Pennsylvania DCNR) considers the potholes and cliffs along the gorge as heritage 

geology sites called erosional remnants.

Prior to construction of Conowingo dam, the river in the current impoundment 

reach and below the dam was a bedrock channel that was difficult-to-navigate for boats. 

Preconstruction maps show two sets of falls upstream of the current Conowingo dam

(Hector’s Falls and Amos’s Falls), although they were essentially a series of rapids where 

the river profile was steeper than in nearby reaches.

Soils

Surficial geologic sediments form a mantle of predominantly unconsolidated 

weathered bedrock, river-transported sediment (alluvium), and gravity-transported 

material (colluvium). Soils are predominantly non-hydric. Some hydric soils exist 

mainly along tributaries.
61

Shoreline Erosion

Shoreline erosion as a result of fluctuations in the impoundment elevation is 

relatively minor at the York Haven Project because it is operated as a run-of-river

facility. Erosion occurs from natural causes (flood flows, storm waves, runoff, 

freeze/thaw action, ice scour) and from recreational usage (boat wakes, foot traffic along

the shore). Erosion rates are not available but are expected to be small and typical for a 

river in this type of setting, with large floods being the primary erosion driver.

The Muddy Run Project upper reservoir shoreline consists largely of a wide and 

gently sloping non-vegetated zone that is alternately exposed and inundated. The zone 

contains unweathered bedrock covered with fragmented weathered bedrock, colluvium, 

and alluvium. It is crossed by gullies, rills, and sheet flow features formed by runoff 

from the surrounding riparian areas or by groundwater seeps. Parts of the excavated

intake canal consist of near-vertical walls of exposed bedrock.

There are three locations with high and moderate erosion along the upper reservoir 

shoreline: weathered bedrock is eroded along the intake canal embankment near the east 

side of the River Road crossing; gully erosion has created deep crevasses in a steep 

channel downstream of the Recreation Lake spillway; and, on the northside of the fingershaped cove to the south of the recreation dam, a top-of-bank erosion scarp face in soils 

developed from the underlying bedrock. Exelon is monitoring erosion at these locations 

regularly and is prepared to mitigate adverse effects as needed. There is minimal to no 

erosion along the remainder of the shoreline with the exception of a 300-foot-long 

location with moderate erosion (i.e., signs of slumping without adverse effects on 

resources) in the northeastern corner of the upper reservoir.

The shorelines around Conowingo Pond and below Conowingo dam consist 

largely of bedrock, unconsolidated natural materials (alluvium, colluvium), and 

disturbed/artificial materials (e.g., walls, fill, rail embankment, and canal tow path berm). 

Low to moderate erosion has been observed along unconsolidated shorelines. Instances 

of high erosion rates have not been observed to encroach on infrastructure. Shoreline 

erosion along tributaries is also considered low to moderate. Shoreline accretion occurs 

at the downstream ends of existing islands in the Conowingo Pond and at or near 

tributary mouths. Deposits are eventually stabilized by natural vegetation growth. 

Sediment Transport 

The Susquehanna River is the largest tributary to Chesapeake Bay and 

consequently contributes the largest sediment load (i.e., 25 percent of the load from nontidal sources; Langland, 2009). The sediment loading is largely a function of flow, but is 

affected by the trapping ability of the lower Susquehanna River reservoirs.

As a result of the run-of-river operation and small reservoir (Lake Frederic), the 

York Haven Project has little control over sediment accumulation in the impoundment. 

However, given its shallow depth of less than 18 feet (with a mean depth of 6 feet), 
62

sediment that may accumulate in the impoundment during low-flow periods is likely 

flushed out to a large extent during high-flow events.

The Muddy Run Project in essence does not contribute to sediment loading in the 

Susquehanna River because it is an off-stream reservoir. Instead, a fraction of the 

suspended sediment contained in the Susquehanna River water that is regularly pumped 

into the Muddy Run reservoir is expected to settle out of the water column. Net sediment 

deposition rates in the reservoir are not available.

USGS assessed the potential sediment trapping capacity of the lower Susquehanna 

River reservoirs and potential effects on Chesapeake Bay (Langland, 2009). Of the three 

lower river reservoirs—Lake Clarke (Safe Harbor Project), Lake Aldred (Holtwood 

Project), and Conowingo Pond (Conowingo Project)—USGS estimated that only 

Conowingo Pond has any sediment trapping capacity remaining (figure 3-1). Both Lake 

Clarke and Lake Aldred have been in long-term equilibrium for 50 years or more, with 

the amount of sediment exiting the reservoirs equal to the amount of sediment entering 

the reservoirs. USGS estimates that the sediment trapping capacity of the upper and 

middle parts of Conowingo Pond is minimal and that the only remaining capacity is in 

the lower part of the reservoir. In 2008, an estimated 174 million tons of sediment were

stored in the reservoir; the reservoir’s remaining storage capacity is about 30 million tons. 

The volume of sediment entering Conowingo Pond is estimated at 3 million tons/year, of 

which about two thirds (2 million tons/year) is currently being trapped by the reservoir

(Langland, 2009). The suspended sediment loads carried past Conowingo dam into 

Chesapeake Bay are on average 1.1 million tons per year, although the amount varies 

widely, ranging in recent years from 0.3 million ton per year in 2001 to 3.5 million tons 

per year in 1993 (a very wet year).

Sediment trapping will continue until the storage capacity of Conowingo Pond is 

reached, which is projected to occur by 2023 to 2028 (i.e., 15 to 20 years after the 2008 

bathymetric survey). However, the sediment trapping efficiency can be highly variable, 

depending on rainfall and river flows, reduced sediment loading from the watershed due 

to source control measures, and frequency and magnitude of scour removal events. For 

example, a 20 percent reduction in sediment loading to the river from the watershed 

could extend that period by another 5 to 10 years (i.e., up to year 2038; Langland, 2009). 

Once Conowingo Pond reaches the sediment trapping capacity, sediment loads delivered 

to the Chesapeake Bay via the Susquehanna River would equal the load delivered into the 

head of the three reservoirs (Lake Clarke), resulting in a load increase relative to current 

conditions.
63

Figure 3-1. Changes in vertical cross-sectional area for selected years and remaining 

sediment-storage capacity in Conowingo Pond (Source: Langland, 2009).

Sediment transport processes in the lower Susquehanna River are strongly affected 

by discharge rates. The river carries high sediment loads during peak flow events. In 

addition, sediment is mobilized during such events through scour in the lower 

Susquehanna River reservoirs (Lake Clarke, Lake Aldred, and Conowingo Pond). These 

peak flow events interrupt periods of gradual sediment accumulation in the reservoirs. 

Langland (2009) indicated that the threshold for scour in Conowingo Pond occurs at 

390,000 cfs. He suggested that tropical storm Agnes, with a peak discharge rate of 

1,120,000 cfs, resulted in scour of 20 million tons of sediment from the three reservoirs. 

However, the Sediment Introduction and Transport Study (URS and Gomez and Sullivan, 

2012a) prepared for Exelon suggests that a threshold of approximately 400,000 cfs is not 

adequate to trigger scour in Conowingo Pond. Hirsch (2012) suggested that Conowingo 

Pond is approaching a long-term equilibrium where the average rate of deposition would 

equal the average rate of scour; he suggested that the threshold flow rate for scour is now 

between 175,000 and 300,000 cfs. Zhang et al. (2013) observed increasing flownormalized loads of suspended sediment at Conowingo dam since the mid-1990s, which 

supports the gradual filling of the reservoir.

Downstream of Conowingo dam, the streambed consists of a discontinuous 

surface of exposed bedrock or bedrock with a much thinner alluvial cover than in 

Conowingo Pond. The streambed is likely in similar condition to the bed prior to dam 
64

construction because the flow in the rapids was strong enough to inhibit 

sediment deposition.

3.3.1.2 Environmental Effects

Shoreline Erosion

Minor shoreline erosion effects at the York Haven Project would continue to occur 

as a result of natural forces similar to current conditions, considering that project 

operation would remain unchanged. York Haven Power does not propose any shoreline 

erosion control measures. 

In preparation for the construction of the nature-like fishway, York Haven Power

proposes to develop an erosion and sediment control plan and apply to Pennsylvania DEP

for a National Pollutant Discharge and Elimination System (NPDES) permit for 

stormwater discharge associated with construction activities, as specified in the 

explanatory statement filed with the Settlement Agreement. York Haven Power would

also map usable rocks and boulders downstream of the dam to be used for the 

construction of the fishway. Construction would occur during three low-flow seasons. 

Rocks and boulders retrieved from the river would be stored in designated staging areas 

until fishway construction begins.

Shoreline erosion due to upper reservoir level fluctuations at the Muddy Run 

Project, combined with occasional natural overflows over the Recreation Lake spillway

after rain events, surface runoff, mass-wasting, and wind induced waves, is considered 

minimal with the exception of three locations. Specifically, as described above, 

weathered bedrock is eroded along the intake canal embankment, gully erosion has 

created crevasses downstream of the Recreation Lake spillway, and a top-of-bank scarp 

face formed along the shoreline of the finger-shaped cove to the south of the recreation 

dam. Aside from regular monitoring for erosion at these locations, Exelon plans to 

implement an SMP that would allow modifications to shoreline vegetation to construct 

erosion control measures, provided the modifications do not impair the overall function 

of the vegetated buffer. Trees and shrubs on steep slopes will be maintained 

whenever possible.

Shoreline erosion within Conowingo Pond and downstream of the Conowingo 

Project dam is minor and largely caused by natural processes. Project-induced erosion 

effects are not discernible from natural effects. As part of its SMP measures, Exelon 

proposes to adopt BMPs for controlling sediment introduction from lands within the 

project boundary (see further discussion in section 3.3.5, Recreation and Land Use 

Resources). Proposed erosion control measures include monitoring and remediation of 

identified and characterized erosion-prone areas.
65

Our Analysis

Shoreline erosion from the continued operation of the York Haven Project would 

be minor. For construction of the nature-like fishway, any effects would be minimal with 

the proper implementation of York Haven’s proposed erosion and sediment control plan. 

In addition, the number of rocks and boulders required for the construction of the fishway

would be small relative to the size of the river and the area where the rocks and boulders 

would be harvested; furthermore, these rocks and boulders would essentially remain part 

of the riverbed, although placed in a different location (i.e., within the course of the 

nature-like fishway).

Overall, shoreline erosion effects from the operation of the Muddy Run Project 

would also be minor. We find that regular monitoring and mitigation (if needed) of the 

active erosion locations along with the implementation of the SMP would provide

adequate measures to control erosion at the upper reservoir. 

Shoreline erosion effects in the Conowingo Project area are largely a function of 

natural high-flow events, wave scour, and mass-wasting processes. Minor shoreline 

erosion, and deposition of eroded shoreline sediment in the reservoir, is expected to 

continue at similar rates as at present, considering that there are no significant changes to 

project operation. We find that the SMP includes adequate measures to address erosion 

control issues in the reservoir.

Sediment Transport 

York Haven Project Area

The small size and shallow depth of the project reservoir, along with the project’s 

run-of-river operation, minimally affects sediment transport in the river. Sediment that 

settles in the reservoir during low-flow periods would be remobilized during high-flow 

events and transported downstream of the dam. York Haven Power is not proposing any 

measures related to sediment transport. The proposed flow redistribution across the dam

after the proposed new fish passage facility is in place would not affect overall sediment 

transport through the project area. 

Muddy Run Project Area

As a pumped storage facility, Muddy Run Project operation would not affect 

sediment loading and transport processes in the Susquehanna River. Sediment suspended 

in the water that is pumped into the upper reservoir would largely remain in suspension 

and be returned to the river during power generation. A small fraction of the suspended 

sediment would settle in the reservoir. The amount of sediment eroded from the upper 

reservoir shoreline and added to the water column would be minimal.

The certification for the Muddy Run Project requires Exelon to pay a total of 

$500,000 per year of “compensatory mitigation” from 2014 to 2030, to the Lancaster 

County Conservation District, the York County Conservation District, and the 
66

Pennsylvania FBC, or to such other conservation district, resource agency, or 501(c)(3) 

organization as directed by Pennsylvania DEP, for the implementation of agricultural 

pasture and barnyard BMPs to address sediment loading to the Susquehanna River and 

other habitat improvement projects including small dam removals.

Conowingo Project Area

As stated above, sediment trapping in Conowingo Pond would continue until its

storage capacity is reached sometime between 2023 and 2038. Thereafter, the full

sediment and nutrient load carried by the river would pass through the reservoir to 

Chesapeake Bay.

The U.S. Army Corps of Engineers (Corps) is currently assessing the lower 

Susquehanna River watershed to identify strategies for reducing sediment loading and 

habitat restoration in the river and in Chesapeake Bay (LSRWA, 2014a). The study 

includes a review of existing data and watershed-level modeling to characterize the 

complex relationship among river flow, sediment loading, and ecological resources. 

Project partners include Maryland DOE, Maryland DNR, SRBC, USGS, Chesapeake Bay 

Program, and The Nature Conservancy. The study, which is expected to be completed in 

the fall of 2014, will include an assessment of the role of scour in the reservoirs and 

evaluate appropriate sediment management strategies to address the effects of future 

scour events. Management options considered by the study could include dredging, 

modifying dam operation, and sediment bypass strategies. Exelon is cooperating with the 

Corps’ Lower Susquehanna River Watershed Assessment (LSRWA) study.

Several agencies and organizations comment that the findings of the Corps’ study 

should be available before the Commission completes its National Environmental Policy 

Act analysis for project relicensing. These entities include the U.S. Environmental 

Protection Agency (EPA); Maryland DNR; SRBC; NMFS; Chesapeake Bay Foundation;

Stewards of the Lower Susquehanna, Inc.; Midshore Riverkeeper’s Conservancy, Inc.;

and the Clean Chesapeake Coalition. The commenters state that Exelon’s proposed 

management plans are not ready for analysis without an understanding of the sedimentrelated effects of scour in Conowingo Pond during peak flow events on the water quality 

and living resources in Chesapeake Bay. 

The Stewards of the Lower Susquehanna, Inc., also recommend that Exelon 

remove at least 4 million tons of sediment annually from the reservoir to eventually 

remove all sediment subject to scouring. The Clean Chesapeake Coalition requests that 

Exelon be required to dredge Conowingo Pond and restore oyster beds north of the Bay 

Bridge and submerged aquatic vegetation (SAV) in the upper Bay and its tributaries that 

were buried by sediment scoured from Conowingo Pond. The Town of Port Deposit, 

American Rivers, and Henry Immanuel also recommend that Exelon prevent and mitigate 

for the downstream effects of scoured sediments. Maryland DNR notes, however, that it 

is premature to conclude that the Corps’ LSRWA study will be adequate to appropriately 

identify and evaluate sediment and nutrient effects on the Bay’s resources related to the 

Conowingo Project.
67

The Nature Conservancy comments that the elimination of coarse-grained 

sediments (sand, gravel, and cobble) via storage in Conowingo Pond, and turbulence and 

high velocities resulting from hydropower operation at the Conowingo Project, adversely 

affect the amount of lower river habitat available to fish species, such as American shad, 

river herring, shortnose and Atlantic sturgeon, map turtle, and freshwater mussels, as well 

as SAV. The Nature Conservancy and American Rivers recommend developing 

alternatives to mitigate the effects of continued operation on living resources. 

Exelon responds that its operation does not increase the volume of sediment 

discharged into Chesapeake Bay and that sediment and nutrients are almost entirely 

introduced to the river during runoff from the watershed, which is outside of Exelon’s 

control. Therefore, Exelon states that it should not be required to mitigate any potentially 

resulting effects and, in fact, Conowingo Pond has been functioning as a BMP preventing 

sediment and nutrients from being transported to the Chesapeake Bay. 

Exelon proposes to conduct a bathymetric survey every 5 years to monitor 

sediment transport and deposition patterns in Conowingo Pond. In addition, as part of its 

Sediment Management Plan, Exelon would control sediment runoff from project lands 

and identify action benchmarks and thresholds at the powerhouse intakes to address 

sedimentation-related issues that might affect project operation. Exelon states that 

sediment going through the turbine typically does not damage the runner, although it 

might cause slight wear of the shaft packing and wicket gate end bushings. The turbines 

would be inspected regularly for signs of abrasion, which would be a benchmark for 

considering sediment removal.

Exelon is further evaluating potential management actions (e.g., hydraulic or 

mechanical dredging) to improve recreational boat access to three recreation areas where 

sediment has been accumulating around the boat launches (Conowingo Creek, Peach 

Bottom Marina, and Broad Creek; see further discussion in section 3.3.5, Recreation and 

Land Use Resources).

Our Analysis

The York Haven Project minimally affects sediment loading. Sediment 

accumulated in the reservoir during low-flow periods is remobilized during high-flow 

events, slightly increasing the suspended sediment concentration and the bedload carried 

by the river at those times. The increase is relatively small due to the shallow depth and 

limited storage capacity of the reservoir and we would not expect the continued run-ofriver operation with the 1.1-foot fluctuation to change the existing minimal contribution 

to sediment loading in the river.

The Muddy Run Project has a negligible effect on sediment transport processes in 

the Susquehanna River and sediment loading to Chesapeake Bay. The “compensatory 

mitigation” requirement of the draft certification does not specifically state what the 

mitigation is compensating for. Funds would be used for BMPs to reduce sediment 

loading to the river and for habitat improvement, including dam removal. This 
68

requirement appears not to be related to any specific project effect, or would not 

necessarily be implemented in the project area. The specific projects that would be 

funded are not identified, and we have no basis for evaluating the benefits of any such 

measures and if they are related in any way to the Conowingo Project. 

Sediment transport issues for the Conowingo Project are more complex. Nearly 

all sediment entering Conowingo Pond is contributed by the river’s upstream watershed; 

contributions from project lands are minimal. Conowingo Pond may be filled sometime 

between 2023 and 2038 and then would reach a state of dynamic equilibrium in which 

the net change in sedimentation (deposition during low flows and scour during floods) 

would remain relatively constant. At that time, on a long-term basis, the full sediment 

load carried by the river would be transported into Chesapeake Bay, as would have 

occurred prior to construction of the lower Susquehanna River reservoirs. High-flow 

events would carry suspended sediment from the river’s watershed, as well as sediment 

scoured from the three lower river reservoirs (Lake Clarke, Lake Aldred, and Conowingo 

Pond). Some of the sediment during high-flow events is currently still being redeposited 

within the remaining storage space in the lower part of Conowingo Pond. Once that 

space is filled, generally all scoured sediment would be carried past the dam. The 

relative contribution of scoured sediment within the total volume of sediment passing the 

dam would vary substantially, as it is a function of factors such as peak flow discharge, 

duration of the high-flow event, and length of time between high-flow events when 

sediment could accumulate in the reservoirs. USGS estimated that the scoured sediment 

load within the total river sediment load below Conowingo dam during 10-year, 25-year, 

and 80-year recurrence flow events would be 22, 25, and 43 percent, respectively 

(Langland, 2013), although these preliminary estimates may be modified in the Corps’

final study report. 

At steady state, areas immediately upstream of the dam would remain turbulent 

with high velocities and inhibit sediment deposition. However, over time, this zone of 

turbulence near the dam could narrow, and there is potential for sediment accumulation 

near the intakes that could affect hydropower operation. As sediment builds up near the 

intakes, sediment-laden water could damage turbines and other hydropower components

due to increased abrasion (Neopane, 2011). Benchmarks established under Exelon’s

Sediment Management Plan should help identify appropriate actions to allow for 

continued operation of the project.

Sand and gravel would continue to be trapped by the three lower Susquehanna 

River reservoirs. However, grain size data show that, as the storage capacity is 

decreasing, the grain size of the bottom sediments in Conowingo Pond has become 

increasingly sandy (Langland, 2013). Once Conowingo Pond has reached its storage 

capacity, more sand is expected to reach the Susquehanna River below the dam, as 

mobilized from the pond during high-flow events. The substrate below Conowingo dam 

consists mainly of bedrock, with some boulders, cobbles, and areas of finer sediments. 

Flow conditions in the river are naturally turbulent with high velocities, inhibiting 

deposition until the change in gradient near the mouth of Deer Creek, about 4 miles 
69

downstream from the dam. The river substrate in this reach was likely similar to today’s 

conditions prior to the construction of Conowingo dam, with areas of localized sediment 

inflows from tributaries. Therefore, high-velocity turbulent flow conditions in the river 

below the dam would eventually transport the sand and gravel that bypass the Conowingo 

dam toward Chesapeake Bay. 

The Nature Conservancy expressed concern about the effect on downstream 

habitat of interception of coarser grained sediment (sand, gravel, and cobble) by 

Conowingo Pond. We find that any attempt to mitigate that effect by placement of 

coarser grained sediments downstream of the dam would likely have limited success 

because of high velocities and turbulence that would transport those materials farther 

downstream and away from areas where habitat enhancement was targeted. 

Once the river enters Chesapeake Bay, and flow velocities and thus the sediment 

carrying capacity of the water decreases, the coarser grained scoured sediments settle out 

of the water column first in the northern part of the Bay. Finer grained particles remain 

suspended in the water column longer and are transported further to the south in the Bay.

This was observed after Hurricane Lee when sands were deposited on the Susquehanna 

Flats, and finer grained sediments were distributed more widely in the Bay 

(Cheng et al., 2013).

The lower Susquehanna River and Chesapeake Bay are affected by sediment 

transport (including sediment scoured from Conowingo Pond). On December 29, 2010, 

EPA established the Chesapeake Bay Total Maximum Daily Load (TMDL) for sediment, 

nitrogen, and phosphorus, with rigorous accountability measures to restore water quality 

in the Bay (EPA, 2013). This TMDL considered the loading of the Bay after the storage 

capacity in the lower Susquehanna River reservoirs has been reached. The current 

TMDL incorporated an estimated current trapping efficiency of Conowingo Pond of 55 

percent for sediment, 2 percent for nitrogen, and 40 percent for phosphorus (see 

additional discussion in section 3.3.2, Water Resources). The TMDL will be 

implemented in phases with an interim target allocation of 60 percent total load 

reductions by 2017, and 100 percent by 2025. EPA will assess a state’s progress toward

meeting TMDL goals every 2 years. 

EPA assumed that the current trapping capacity will continue through the TMDL 

planning horizon of year 2025. If future monitoring shows a reduction in trapping 

capacity, EPA would adjust the milestone loads for upland jurisdictions. These 

jurisdictions might need to increase their sediment-reduction efforts to accommodate the 

loss of trapping capacity in Conowingo Pond. EPA does not expect that changes in the 

sediment-trapping efficiency capacity would alter the amount of sediment that the Bay is 

able to assimilate and, therefore, the allocations in the Chesapeake Bay TMDL are 

expected to remain unchanged.

The ongoing LSRWA (LSRWA, 2014) is evaluating a number of sediment 

management alternatives to reduce the volume of sediment scoured from the three lower 

Susquehanna River reservoirs during peak flows. These sediment management 
70

alternatives include reduction of sediment loading from the watershed, dredging of the 

three reservoirs combined with various dredged sediment transport and placement 

scenarios, agitation dredging and sluicing past Conowingo dam, a sediment bypass tunnel 

to Conowingo dam, and reservoir operational strategies. A representative from SRBC

reviewed the operational sediment management strategies of the three lower Susquehanna 

River reservoirs during the LSRWA quarterly meeting on May 13, 2013 (LSRWA, 

2013a). He concluded that retrofitting the existing dams with sluice gates or other 

bottom outlet works would be difficult and could compromise the dams’ structural 

integrity. He further concluded that, aside from structural constraints, the cumulative 

effect of competing water uses and operational limitations make reservoir operational 

alternatives infeasible, and the significant implementation costs would not be justified by 

only limited spatial and volumetric effects on sediment movement. He summarized that 

these factors warrant dropping the reservoir operational alternatives from further 

consideration. 

Dredging the sediment load entering the reservoirs annually would be challenging 

and complicated by the effects on other resources in the reservoirs (water quality, 

fisheries, and recreational use) and the need for suitable locations for placing large 

volume of sediment, year after year. Exelon estimated dredging costs of about

$50 million per year just to keep up with the annual sediment load of about 3 million tons 

entering Conowingo Pond. However, the final dredging costs would depend significantly

on a wide range of factors including dredging approach, dewatering of dredged 

sediments, placement locations, and constraints due to contaminants in the sediment (e.g., 

LSRWA, 2013b).

Other management scenarios considered in the LSRWA study, such as agitation 

dredging and a bypass tunnel, would in essence move sediment accumulated in the 

Conowingo Pond in advance of high-flow events. These scenarios would maintain the 

total annual sediment load entering Chesapeake Bay, although the added volume of 

scoured sediment in the total transported sediment load during high-flow events would be 

reduced. Instead, sediment loading would be spread out more evenly throughout the year 

with the intent to meet the TMDL in the Bay. 

Based on currently available information, we find that changes in Conowingo 

Project structures and operation are not viable solutions to the sediment transport issue at 

this time. We consider it premature to conclude that dredging of Conowingo Pond would 

be an environmentally acceptable solution. Exelon’s proposal and other entities’ 

recommendations to use the Corps’ regional study as a basis for additional analysis of 

this issue are reasonable. The Corps’ study would provide a better understanding of 

sediment deposition and transport processes in Conowingo Pond, and help establish 

necessary benchmarks for potential actions (e.g., prediction of sediment deposition near 

the intakes that could impede project operation). Exelon’s proposed bathymetric surveys 

in Conowingo Pond at 5-year intervals would allow for verification of model predictions 

and identify appropriate management actions ahead of time. The current schedule calls 

for the Corps’ study to be completed in September 2014. If the study is completed on 
71

schedule, the results of that study would be available for analysis in the final EIS. 

However, the ultimate resolution of this issue would require more than singular actions at 

the Conowingo Project, and instead would require a basin-wide approach involving many 

governmental jurisdictions and other entities. 

3.3.1.3 Cumulative Effects

For the York Haven and Muddy Run projects, shoreline erosion in the reservoirs is 

minimal and the amount of sediment added to the Susquehanna River system would not 

contribute to cumulative effects in the river.

Conowingo Pond would continue to trap coarser grained sediment, until the 

sediment storage capacity of the reservoir is reached. At that time, the total contribution 

to the sediment load entering Chesapeake Bay would increase by approximately 2 million 

tons annually compared to current conditions. However, the Chesapeake Bay TMDL is 

designed to mitigate the effects from this increased sediment loading to the Bay by 

requiring specific load reductions from the seven jurisdictions within the Bay’s 

64,000-square-mile watershed. Regular dredging of Conowingo Pond and placement of 

the dredged material offsite, if deemed feasible, might reduce these load reduction 

requirements for jurisdictions to some extent, although, as recognized by the TMDL, the 

long-term solution would require a basin-wide approach.

3.3.2 Water Resources

3.3.2.1 Affected Environment

The Susquehanna River Projects affect water resources within the lower 60 miles 

of the mainstem of the Susquehanna River. 

Water Quantity

The Susquehanna River drains portions of western and central New York State, a 

large portion of Pennsylvania, and a small part of Maryland. Five hydroelectric projects 

on the lower Susquehanna River use flow from the river and its tributaries to generate 

electricity (table 3-1). No large mainstem reservoirs or hydropower projects are located 

on the Susquehanna River upstream of the York Haven Project, although there are Corps’

flood control projects on several tributaries (see figure 1-1). 
72

Table 3-1. Hydroelectric projects on the lower Susquehanna River (Source: York 

Haven Power, 2012; Exelon, 2012a, 2012b; FERC, 2008). 

Project

River 

Mile

Generating 

Capacity 

(MW)

Maximum 

Plant 

Discharge 

(cfs)

Drainage 

Area 

(sqm)

Reservoir 

Surface 

Area 

(acres)

Usable 

Storage 

(acre-feet)

York Haven 55 19.62 17,000 24,973 2,218 1,700

Safe Harbor 32.2 417 113,000 26,117 7,360 68,870a

Holtwood 24.6 195.5 62,100 26,794 2,400 15,224b

Muddy Run 22 800.25 32,000 9.2 892 33,894

Conowingo 10 574.54 85,000 27,100 9,000 71,000 a Storage volume is based on the upper 17 feet, although actual drawdowns are much 

less.

b Between elevation 163.5 feet and the top of the flashboards/rubber dam at elevation 

169.75 feet.

York Haven Project

Table 3-2 shows monthly flow statistics for the Susquehanna River at York Haven 

Project, based on flows at the Marietta USGS gage, about 10 miles downstream from the 

York Haven Project (figure 3-2). Monthly flows are generally highest in March and 

April and lowest in July, August, and September. The range of monthly flows observed 

at the Marietta gage is substantial, from a low of 2,066 cfs to a high of nearly 1 million 

cfs (Hurricane Agnes).
73

Table 3-2. Prorated flows at York Haven Project based on monthly flow data from 

USGS gage no. 01576000 Susquehanna River at Marietta, Pennsylvania,

for October 1, 1967, to September 30, 2009 (Source: USGS, 2013, as 

modified by Staff).

Month Mean Median Maximum Minimum

10% 

Exceedance

90% 

Exceedance

Jan 41,560 25,943 534,243 4,036 90,312 11,636

Feb 47,042 30,940 428,548 6,342 98,970 14,413

Mar 70,392 54,001 426,626 8,648 134,522 23,263

Apr 73,049 58,325 414,135 16,815 140,383 27,260

May 44,318 35,552 214,274 11,050 77,811 17,872

Jun 32,006 21,572 999,304 4,641 52,954 10,570

Jul 18,278 13,356 214,274 3,565 33,707 6,458

Aug 13,467 9,196 191,213 2,527 24,983 4,892

Sep 16,977 8,316 523,674 2,066 30,757 4,256

Oct 21,599 10,762 236,374 3,430 49,446 5,150

Nov 33,162 25,223 254,630 4,314 65,772 7,625

Dec 46,623 35,552 334,383 4,910 92,243 15,480

Annual 38,133 24,694 999,304 2,066 83,115 6,774

Note: Data from USGS gage no. 01576000 about 10 miles downstream from the 

York Haven Project were prorated by 24,973/25,990 to account for the 

difference in the drainage area between the gage and York Haven dam.

Safe Harbor Project

Water discharged from York Haven dam flows downstream through about 

13 miles of riverine habitat to the beginning of the 10-mile-long Lake Clarke, the 

impoundment of the Safe Harbor Project. The Safe Harbor Project does not have a 

minimum flow requirement in its license (which expires in 2030), and normal maximum 

impoundment elevation ranges between 227.2 feet in summer to 228.0 feet in winter. 

The project is operated to support peak electricity demands and, since 1997, a fish lift has 

operated at this facility to pass resident and migratory fish upstream during the spring.
74

Figure 3-2. Stream gages in the Susquehanna River Projects area (Source: Staff).
75

Holtwood Project

Water discharged from Safe Harbor dam flows immediately into Lake Aldred, the 

Holtwood Project impoundment. Holtwood dam is located about 8 river miles 

downstream of Safe Harbor dam, and full generation from the Safe Harbor Project

substantially exceeds the hydraulic capacity of the Holtwood Project, which results in 

spillage at Holtwood dam and a water surface gradient within Lake Aldred; at lower 

releases from Safe Harbor the water surface gradient within Lake Aldred is generally flat. 

The generation capacity of the Holtwood Project was recently upgraded to 195.5 MW

with a daily minimum flow of 800 cfs and a flow capacity of about 62,100 cfs. Even 

after the Holtwood expansion, the Safe Harbor maximum discharge still exceeds the 

Holtwood capacity by about 40,000 cfs. Lake Aldred is managed to maintain a minimum 

operating level of elevation 167.5 feet from May 15 through September 15 to support 

reservoir recreational uses and access. The top of the flashboards at the dam are at 

elevation 169.75 feet, and the minimum operating level during the balance of the year is 

elevation 163.5 feet. Leakage through the dam and flow from a 10-inch-diameter pipe 

through the dam maintain a small, continuous flow in the bypassed reach. The flow rate 

through the pipe depends on the water surface elevation of Lake Aldred, but PPL 

estimated it at 11 cfs at maximum normal water elevations. Leakage through the 

flashboards, which varies based on reservoir elevation and the adequacy of seals between 

flashboards, ranges between 4 and 40 cfs. When generating units are not operating, 

leakage through the units maintains about 210 cfs continuous flow in the tailrace (FERC, 

2008).

When the Holtwood Project is not generating, the water level in Conowingo Pond, 

created by Conowingo dam 14.6 miles downstream, normally controls the tailwater 

elevation below the Holtwood powerhouse. The bypassed reach on the western side of 

the river is primarily rock ledge interspersed with shallow, interconnected pools with 

some vegetation and receives flow only during spillage over the dam. 

Muddy Run Project 

The Muddy Run Project, which is on the east side of the Susquehanna River, uses 

Conowingo Pond as its lower reservoir. Although there are no USGS gaging stations on 

Muddy Run, according to Exelon, the average annual flow from Muddy Run to the 

Muddy Run reservoir is about 7 cfs. 

Muddy Run’s upper reservoir has a usable storage of 33,894 acre-feet between 

elevations 470 and 520 feet. Conowingo Pond has an effective storage of about 

34,050 acre-feet between elevation 105.2 feet and 109.2 feet, the typical fluctuation 

range. The Conowingo Project’s existing license conditions allow fluctuations between 

101.2 and 110.2 feet. The Muddy Run powerhouse turbines have a maximum generating 

discharge capacity of 32,000 cfs and a maximum pumping capability of 28,000 cfs. 
76

Recreation Lake, which was created by impounding an arm of the Muddy Run 

reservoir, is maintained at a constant elevation of 520 feet with a surface area of about 

100 acres. 

Table 3-3 provides the average monthly withdrawal and discharge for 2006

through 2010 and shows that the average daily withdrawals and discharges range from

about 11,750 to about 15,100 acre-feet. The monthly numbers in this table indicate that 

the annual discharge is about 35 acre-feet higher than the withdrawal from Conowingo 

Pond. Table 3-4 provides the water withdrawal and return characteristics for three 30-

day high-flow periods (between March and April) and three 30-day low-flow periods 

(between August and September). These data show that Muddy Run operation does not 

substantially vary between low-flow and high-flow periods. 

Table 3-3. Muddy Run Project monthly average withdrawals and discharge for 2006 to 

2010 (Source: Gomez and Sullivan and Normandeau, 2012b).

Month

Average Daily 

Withdrawal (acre-feet)

Average Daily 

Discharge (acre-feet)

January 13,899 14,074

February 13,825 13,828

March 11,757 11,840

April 11,938 11,754

May 14,381 14,675

June 14,915 15,102

July 14,568 14,206

August 13,571 13,844

September 14,448 14,289

October 14,522 14,451

November 13,227 13,350

December 13,924 13,979
77

Table 3-4. Summary of daily and hourly Muddy Run Project discharge and withdrawal characteristics for 30-day highand low-flow periods for 2008 to 2010 (Source: Exelon, 2012a, as modified by Staff). 

Flow Period

Average 

Flow at the 

Marietta 

USGS gage 

(cfs)

Average

Daily 

Withdrawal 

from 

Conowingo 

Pond (acrefeet per day)

Average 

Daily 

Discharge to 

Conowingo 

Pond (acrefeet per day)

Maximum 

Daily 

Withdrawal 

from 

Conowingo 

Pond (acrefeet per day)

Maximum 

Daily 

Discharge to 

Conowingo 

Pond (acrefeet per day)

Maximum 

Hourly 

Withdrawal 

from 

Conowingo 

Pond (cfs)

Maximum 

Hourly 

Discharge to 

Conowingo 

Pond (cfs)

Water Withdrawal and Returns Statistics for 30-Day High-Flow Periods

Mar 5 - Apr 3, 

2008 132,645 28,537 29,028 43,345 46,163 34,274 36,539

Mar 11 - Apr 9, 

2009 54,194 17,597 18,378 35,793 39,409 29,410 32,120

Mar 13 - Apr 

11, 2010 96,459 19,074 18,801 34,932 36,535 29,484 32,158

Water Withdrawal and Returns Statistics for 30-Day Low-Flow Periods

Aug 28 - Sep 

26, 2008 6,523 28,823 28,087 40,299 41,891 29,187 37,616

Sep 1 - Sep 30, 

2009 13,722 25,697 26,381 33,186 47,640 29,187 34,460

Sep 1 - Sep 30, 

2010 5,691 26,678 27,060 37,732 49,785 27776 37,022
78

Conowingo Project

The Conowingo Project is the farthest downstream dam on the Susquehanna 

River. It is located 10 miles upstream from the Chesapeake Bay and impounds the river 

about 14 miles upstream to the Holtwood Project, creating a 9,000-acre reservoir that 

contains 310,000 acre-feet of design storage capacity and 71,000 acre-feet of usable 

storage. On a daily basis, the Conowingo Project operates on a run-of-river/peaking basis 

and generates 574.54 MW at full generating capacity. Conowingo dam uses a limited 

active storage in combination with the operation of the Muddy Run Project to meet peak 

electrical demand. Two fish lifts at this facility (east and west) seasonally pass resident 

and migratory fish upstream. 

Conowingo Pond serves as the source of cooling water for the 2,186-MW PBAPS, 

about 7 miles upstream of Conowingo dam, which has a maximum withdrawal capacity 

of 3,450 cfs. The York Energy Center is permitted to withdraw up to 20 cfs for cooling 

water. The pond is also a public water supply source for the city of Baltimore, Harford 

County (Maryland), and the Chester (Pennsylvania) Water Authority. The permitted 

range of water level fluctuation in the impoundment is 9 feet, from elevation 101.2 to 

110.2 feet (figure 3-3). Exelon states that, although 9 feet of fluctuation is permitted, the 

current operating regime typically restricts fluctuations to about 4.5 feet (between 

elevation 104.7 to 110.2 feet) to minimize the potential for intake difficulties at PBAPS 

and cavitation within the Muddy Run turbines. During summer weekends, the

impoundment water level is maintained at elevation 107.2 feet to provide a water level 

suitable for summertime recreational use. Critical water level elevations for Conowingo 

Pond include the following:

• 107.2 feet: The pond must be maintained at this elevation on weekends between 

Memorial Day and Labor Day to meet recreational needs;

• 104.7 feet: Below this level, Muddy Run cannot operate its pumps due to 

cavitation;

• 104.2 feet: PBAPS begins experiencing cooling water problems when the 

elevation of the pool drops to this level;

• 100.5 feet: Below this elevation, the Chester Water Authority is unable to 

withdraw water from the pond;

• 99.2 feet: The Nuclear Regulatory Commission license for PBAPS requires the 

plant to shut down completely at this water level; 

• 98.0 feet: The York Energy Center cannot withdraw water below this elevation; 

and

• 91.5 feet: The city of Baltimore cannot withdraw water from the pond below this

water elevation.
79

Figure 3-3. Conowingo monthly pond elevations, January 2004 through December 

2010 (Source: URS and Gomez and Sullivan, 2012b). 

A minimum flow regime was established in a Settlement Agreement in 1989 

between Exelon and several federal and state resource agencies. The Settlement 

Agreement specifies that the flows represent turbine releases and exclude gate leakage. 

Table 3-5 shows the 1989 negotiated minimum flow schedule agreed to by all parties.

The Commission granted temporary flow variances to Exelon on six occasions 

over the period 1998 to 2011(1998, 1999, 2001, 2002, 2005, and 2007) during summer 

drought periods, permitting leakage to be counted toward the minimum flow requirement. 

Flows released from Conowingo dam are measured by USGS gage no. 01578310 

immediately downstream of the dam (table 3-6). Flows are generally highest in March 

and April and lowest in July, August, and September. The peaking operation of the 

Conowingo Project during lower flow periods often results in substantial changes in the 

flow and stage (figure 3-4) in the river below Conowingo dam. Muddy Run Project 

operation also affects the water level of Conowingo Pond as figure 3-5 shows. 
80

Table 3-5. Minimum flows for the Conowingo Project agreed upon in 1989 Settlement 

Agreement as measured at the upstream USGS Marietta gage

(Source: Exelon, 2012b).

Date Minimum Flow

March 1 - March 31 3,500 cfs or natural inflow, whichever is less;

April 1 - April 30 10,000 cfs or natural inflow, whichever is less;

May 1 - May 31 7,500 cfs or natural inflow, whichever is less;

June 1 - September 14 5,000 cfs or natural inflow, whichever is less;

September 15 - November 30 3,500 cfs or natural inflow, whichever is less; and

December 1 - February 28 3,500 cfs intermittent (maximum 6 hours off 

followed by equal amount on).

Table 3-6. Monthly flow data (cfs) from USGS gage no. 01578310 Susquehanna River 

at Conowingo, Maryland, for October 1, 1967, to September 30, 2009

(Source: Exelon, 2012b).

Month Mean Median Maximum Minimum

10% 

Exceedance

90% 

Exceedance

Oct 23,755 13,800 245,000 295 57,170 3,750

Nov 36,037 28,700 272,000 303 70,410 5,807

Dec 50,533 40,300 357,000 777 98,350 13,610

Jan 45,340 30,250 622,000 511 93,980 10,210

Feb 50,783 36,800 470,000 758 98,500 15,500

Mar 73,846 58,900 462,000 287 139,000 24,410

Apr 76,957 61,800 467,000 6,090 144,000 29,690

May 47,092 39,400 235,000 5,220 81,100 18,100

Jun 34,894 24,500 1,120,000 622 59,000 8,658

Jul 20,001 15,700 213,000 269 37,500 5,421

Aug 14,917 10,650 202,000 367 28,280 4,490

Sep 19,109 10,400 662,000 363 35,240 3,037

Annual 41,026 27,800 1,120,000 269 85,400 5,840
81

Figure 3-4. Flow and stage variation at USGS gage no. 01578310 downstream of 

Conowingo dam (Source: USGS, 2013, as modified by Staff).
82

Figure 3-5. Typical impoundment and Conowingo tailrace flow fluctuations during a 

low-flow period (Source: USGS, 2013; Gomez and Sullivan and 

Normandeau, 2012b, as modified by Staff).
83

Peak Flows

Normal annual high flows (figure 3-6) in the lower Susquehanna River occur in 

the late winter and spring. Extreme flood events such as those in late June 1972, and 

September of 1975, 2004, and 2011 were the result of rainfall from tropical systems 

Agnes, Eloise, Ivan, and Lee, respectively. The other noticeable high-flow event 

(January 1996) was the result of heavy rain, snowmelt, and ice jams.

Note: Data for the Marietta gage are not prorated.

Figure 3-6. Peak annual flows at the Marietta and Conowingo USGS gages, 1968 to 

2012 (Source: USGS, 2013, as modified by Staff).

Water Use

Water in the Susquehanna River Basin is used for hydropower production and 

cooling for fossil and nuclear power plants, as well as for municipal and private water 

supply, agricultural production, and recreation. Consumptive water use in the basin is 

largely for public water supply diversion and utility power generation, with smaller uses 

for recreation, manufacturing, mining, and educational facilities (figure 3-7). The 

maximum approved daily consumptive water use in the Susquehanna River Basin is 

563.1 million gallons per day (mgd), and the majority of the use occurs in the lower 

basin. About half of the water used each year occurs during low-flow periods (i.e., July 

through November), with peak use in July.
84

Figure 3-7. Consumptive water use in the Susquehanna River Basin (Source: SRBC, 

2013).
85

Water use for utility power generation in the lower Susquehanna River includes

five hydroelectric projects (York Haven, Safe Harbor, Holtwood, Muddy Run, and 

Conowingo) and two nuclear power plants (Three Mile Island and PBAPS).37 PBAPS

requires about 2,230 mgd (3,450 cfs) at full power operation, and the majority of the 

water is returned to Conowingo Pond. The York Energy Center, a natural gas electric 

generation facility, withdraws cooling water about 8 miles upstream of Conowingo dam, 

at RM 18. Table 3-7 summarizes the consumptive water use for these electric generation 

projects.

Table 3-7. Consumptive use for power generation in the lower Susquehanna River

(Source: York Haven Power, 2012; Exelon, 2012b).

Facility

Daily Consumptive Water Use 

(mgd) (cfs)

Three Mile Island 21.0 32.5

York Energy Center 12.62 19.5

PBAPS 28.0 43.3

Note: The 30-day average consumptive use at Three Mile Island is 18.0 mgd. 

Water transported from the Susquehanna River Basin for use outside the basin is 

considered an out-of-basin diversion. Table 3-8 provides the existing out-of-basin 

diversion locations and their authorized diversion volumes as approved by SRBC.

 

37 In addition, on June 30, 2014, Exelon filed an application for Non-Project Use 

of Conowingo Lands and Reservoir with the Commission. The application requests the 

approval of an agreement to allow Old Dominion Electric Cooperative (ODEC) to use 

project lands and waters for the withdrawal and discharge of water from and into the 

Conowingo Reservoir necessary to support the combined-cycle electric power generating 

plant that ODEC proposes to build and operate in Cecil County, Maryland 

(Wildcat Point Project). Construction of the Wildcat Point Project is scheduled to 

commence in January 2015.
86

Table 3-8. Out-of-basin diversions in the lower Susquehanna River (Source: York 

Haven Power, 2012; Exelon, 2012b).

Name Location/Description

Million Gallons Per 

Day (mgd) cfs

City of Aberdeen, 

Maryland

Deer Creek to 

Chesapeake Bay

3.0 mgd, but limited to 

1.8 mgd as of 2008

4.6 and 2.8

Baltimore, 

Maryland

Susquehanna River to 

Chesapeake Bay

250 mgd, but limited by 

pumping capacity to 

137 mgd; limited to 64 

mgd during low flowsa

387, 212,

99,

respectivelya

Chester, 

Pennsylvania 

Water Authority

Susquehanna River to 

Delaware River Basin

30 46

Chester, 

Pennsylvania 

Water Authority

Octoraro Creek to 

Delaware River Basin

30 46

Coatesville, 

Pennsylvania,

Municipal Water 

Authority

West Branch Octoraro 

Creek to Delaware 

River Basin

2.0 3.1

Morgantown 

Properties, L.P., 

New Morgan 

Borough, 

Pennsylvania

Conestoga River to 

Delaware River Basin

0.004 0.006

Perryville, 

Maryland

Susquehanna River to 

Chesapeake Bay

1.0 1.5

a These values are from the Conowingo final license application; the remaining values 

are from the York Haven final license application.

Water Quality

Because the Susquehanna River Projects may affect water quality within the lower 

60 miles of the mainstem Susquehanna River, we discuss the overall water quality within 

this reach of the lower river, as well as water quality conditions at each project. 

The mainstem of the Susquehanna River in York, Lancaster, and Dauphin 

counties, Pennsylvania (the reach from York Haven downstream to Conowingo Pond), is 

classified as a warmwater fishery and migratory fishery (25 Pa. Code §93.9o) and is 

subject to specific water quality criteria that are applicable statewide for warmwater 

fishery and migratory fishery streams. The Pennsylvania-Maryland border bisects 
87

Conowingo Pond about 5.7 miles upstream of Conowingo dam, so the lower 15.7 miles 

of the Susquehanna River are within the state of Maryland, which has its own stream 

classification system and water quality criteria. Under the Maryland classification system 

(Code of Maryland Regulations Title 26, Subtitle 08, Chapter 2), Conowingo Pond is 

classified as Use I-P (Water Contact Recreation, Protection of Aquatic Life and Public 

Water Supply). The Susquehanna River from Conowingo dam downstream to the 

confluence with Chesapeake Bay is classified as Use II (Support of Estuarine and Marine 

Aquatic Life and Shellfish Harvesting – includes applicable Use I-P categories). 

Chesapeake Bay tidal tributaries, including the Susquehanna River (which is tidal in the 

lower 5 miles of the reach below Conowingo dam), have sub-category designations of 

“Migratory Spawning and Nursery Use” and “Open Water Fish and Shellfish Use” on a 

Bay Segment scale during specified periods of the year. Table 3-9 summarizes the

stream classifications and associated water quality criteria for the lower 

Susquehanna River.

Table 3-9. Summary of stream classifications and water quality criteria for the lower 

Susquehanna River (Source: 25 Pa. Code §93.7; Code of Maryland 

Regulations Title 26, Subtitle 08, Chapter 2).

Stream Classification Parameter Criteria

Pennsylvania

Warmwater fishery and 

migratory fishery

Water 

temperature

Maximum allowable temperature varies 

by month, ranging from 40°F (4.4°C) in 

the over-winter period to 87°F (30.6°C) 

in the mid-summer

DO Minimum daily average of 5.0 

milligrams per liter (mg/L); minimum 

instantaneous of 4.0 mg/L

pH Between 6.0 and 9.0 units

Maryland

Use I-P Water 

temperature

The maximum temperature outside of a 

mixing zone (i.e., an area where an 

effluent mixes with surface waters) may 

not exceed 90°F (32°C) or the ambient 

temperature of the surface water,

whichever is greater; a thermal barrier 

that adversely affects aquatic life may 

not be established

DO Minimum instantaneous of 5.0 mg/L
88

Stream Classification Parameter Criteria

Use II (downstream of 

Conowingo Dam)

Water 

temperature

Same as above for Use I-P

DO 2/1 through 5/31: ≥ 6.0 mg/L for 7-day 

average; 5.0 mg/L as instantaneous 

minimum

6/1 through 1/31: ≥ 5.5 mg/L for 30-day 

average; 4.0 mg/L for 7-day average; 

3.2 mg/L as instantaneous minimum 

(year-round); Shortnose sturgeon 

criteria: 4.3 mg/L as instantaneous 

minimum at water temperature greater 

than 77°F (29°C)

An excellent source of long-term data for water quality in the lower Susquehanna 

River (although with some data gaps) is from the USGS Harrisburg gage No. 01570500, 

located 13 miles upstream of the York Haven Project. Figures 3-8 through 3-10 provide 

a summary of water temperature, DO, and pH data available from the Harrisburg gage for 

the period November 2008 to November 2013 (the past 5 years). These data indicate that 

Susquehanna River water quality entering the York Haven Project area generally meets 

Pennsylvania water quality standards for these parameters during most of the past 5 

years. For water temperature, in 3 of the past 5 years (2010, 2011, and 2012) water 

temperatures did exceed the maximum state standard during parts of the summer period, 

but this did not occur in 2009 and 2013 (figure 3-8). For DO levels, there was only one

event in the past 5 years when DO failed to meet the minimum instantaneous criteria of 

4.0 milligrams per liter (mg/L), and that minimum DO levels generally exceeded 5 mg/L 

except in the summer of 2010 (figure 3-9). Generally, pH levels remained within the 

criteria range, except for short periods in 2009, 2010, and 2012 when the maximum level 

of 9.0 was exceeded (figure 3-10). 
89

Figure 3-8. Summary of Susquehanna River water temperature data at Harrisburg, 

Pennsylvania, 2008 to 2013 (Source: 

http://waterdata.usgs.gov/pa/nwis/uv?site_no=01570500).
90

Figure 3-9. Summary of Susquehanna River DO data at Harrisburg, Pennsylvania, 

2008 to 2013 (Source: 

http://waterdata.usgs.gov/pa/nwis/uv?site_no=01570500).
91

Figure 3-10. Summary of Susquehanna River pH data at Harrisburg, Pennsylvania, 

2008 to 2013 (Source: 

http://waterdata.usgs.gov/pa/nwis/uv?site_no=01570500).

Other water quality data are available for the lower Susquehanna River from 

several other sources, including monitoring studies conducted by government agencies 

and other studies conducted by utilities associated with the operation of hydroelectric, 

nuclear, and fossil-fuel generating stations. SRBC monitors water quality throughout the 

Susquehanna River Basin and periodically publishes reports on the results of its 

monitoring. Its large river assessment project has monitored water quality and biological 

(macroinvertebrates) parameters throughout the basin since 2007, and released its most 

recent report on that program in September 2011 (Shenk, 2011). Shenk (2011) concluded 

that overall water quality in the Susquehanna River is fairly good. For the monitoring 

station closest to the lower Susquehanna River, located at the mouth of the tributary 

Juniata River upstream of Harrisburg, monitoring at that station indicated slightly 

impaired conditions (Shenk, 2011). Because many of the other monitoring studies have 

been related to the operation or licensing of energy facilities in the lower river, those 

study results will be discussed for each project discussed in this draft EIS.
92

York Haven Project

York Haven Power conducted continuous water quality monitoring from May 

through October 2010, to support relicensing. Parameters sampled at seven sites within 

the project area included water temperature, DO, and pH.

Water temperatures ranged from 52°F to 93°F and closely mimicked ambient air

temperatures. Water temperatures occasionally exceeded the maximum state criteria 

(87°F) at sample sites, although those exceedances occurred most often at the shallow 

shoreline sample site on Shelley Island and at the most upstream sample site at the head 

of the project impoundment. In contrast, the powerhouse tailrace sample site had

generally cooler water temperatures with fewer exceedances of state water temperature 

criteria.

DO levels generally met or exceeded state standards, except at a shoreline sample 

site on Hill Island in Lake Frederic and at the east channel site upstream of the dam. 

However, the Hill Island site failed to meet average daily minimum DO levels on only 4 

percent of the sample days, and failed to meet instantaneous minimums in only 2.7 

percent of the data. The east channel site only failed to meet minimum DO standards 0.9 

percent of the time. Diurnal DO patterns were observed in all locations, as influenced by 

photosynthesis and respiration, and fluctuations in DO levels were greatest in the warmer 

summer months and in areas of Lake Frederic with denser growth of SAV.

Generally, pH levels remained within state standards, but did show diurnal 

variation, probably due to fluctuations in carbon dioxide levels associated with biological 

activity. Inflowing waters to the project had fewer exceedances of state standards than 

waters being discharged from the project, but project outflows exceeded state criteria 

(higher than a pH of 9.0) only 2.9 percent of the time. Most of those exceedances ranged 

from 9.1 to 9.3 units. Minimum pH levels seldom dropped below neutral (pH = 7.0), 

with the lowest value of 6.3 observed at the shoreline sample site on Shelley Island.

Muddy Run Project 

Exelon conducted water quality studies in multiple years prior to filing the final 

license application: 2006, 2007, 2010, and 2011. The surveys are summarized as 

follows:

• In 2006, Exelon continuously monitored water temperature, DO, and pH in the 

project discharge for one month from August 8 to September 3.

• The 2007 surveys involved spot measurements of water temperature and DO in 

the project discharge during low-flow and high-temperature periods in July and 

August.

• In 2010, Exelon monitored water temperature, DO, pH, specific conductivity, 

turbidity, and chlorophyll a via biweekly depth profile sampling from April 

through October along a single transect (three stations) in the upper reservoir, 

and continuously monitored water temperature, DO, pH, and specific 
93

conductivity at the cylinder gate intake for Unit 1 and Unit 2 in the upper 

reservoir power canal, and in the tailrace where Units 3 and 4 discharge into 

Conowingo Pond.

• In 2011, Exelon continued water quality monitoring in July and August in both 

the reservoir and the tailrace by weekly sampling of water quality depth profile 

data (water temperature, DO, pH, specific conductivity, and turbidity) at two 

locations in the project’s upper reservoir, and three locations in Conowingo 

Pond both upriver and downriver of the tailrace. Exelon also conducted 

continuous monitoring of water quality parameters (water temperature, DO, 

pH, and specific conductivity) at the cylinder gate intake for Unit 1 and 2 in the 

upper reservoir power canal, from the tailrace at the Unit 1 and 2 discharge

into Conowingo Pond, and in Conowingo Pond 0.25 mile upriver of the project

tailrace.

Tables 3-10 and 3-11 summarize the water quality data collected by Exelon over 

the 4 years of monitoring in the tailrace and the upper reservoir. These data indicate that 

waters discharged from the project generally met state standards (table 3-10), although 

DO levels occasionally dropped below state standards during the warmer summer 

months. The Muddy Run reservoir does not thermally stratify, but does exhibit DO 

stratification in the main body of the reservoir in some locations, with DO levels as low 

as 2.4 mg/L at depth (table 3-11). The monitoring also found that there is substantial 

mixing occurring in the reservoir near the head of the intake canal during project 

operation, particularly during pumping operation when Susquehanna River (Conowingo 

Pond) waters, which are typically well-oxygenated, are entering the reservoir. In 2011, 

monitoring at times showed a weak inverse DO stratification (higher DO in deeper water 

and lower DO in surface water) as Susquehanna River waters entered the reservoir at 

depth, under the Muddy Run reservoir surface waters that were lower in DO. All other 

measured parameters met state standards.
94

Table 3-10. Summary of water quality data collected in or near the tailrace of the Muddy Run Pumped Storage Project, 

2006 through 2011 (Source: Exelon, 2012a; Normandeau and Gomez and Sullivan, 2012p).

Parameter 2006 2007 2010 2011

Water 

temperature

Met state water quality 

criteria; max

recorded=86.7°F 

Met state water quality 

criteria; temperatures in 

July about 4°F cooler than 

in August

Met state water quality 

criteria; temperatures 

ranged from 57.6 to 

86.0°F; temperatures were 

higher than the long-term 

53-year average (up to 

10°F in some months) in 

April through September 

and lower in October

Generally met state water 

quality criteria; minimum 

and maximum recorded 

temperatures ranged from 

72.1 to 87.3°F with cooler 

temperatures in August; no 

temperature stratification 

was observed at any of the 

tailrace monitoring 

locations, but diurnal 

cycles were observed, 

particularly in Muddy Run 

reservoir waters 

DO Met state water quality 

criteria; min recorded=5.2 

mg/L. DO levels in the 

tailrace typically decreased 

by 1 to 1.5 mg/L during 

generation and increased 

when generation stopped 

or the number of 

generating units was 

reduced 

Met state water quality 

criteria; average DO was 

6.6 mg/L in July and 6.1 

mg/L in August

Some violations of state 

water quality criteria; 

seasonal decrease in DO 

levels from high in April to 

lows in August; average 

daily DO value < 5.0 mg/L 

on 3 days in July and 1 day 

in August; instantaneous 

DO values were less than 

4.0 mg/L on 12 days in 

July and 2 days in August

Mostly met state water 

quality criteria; average 

daily DO values were 

above 5.0 mg/L at all 

stations and dates, but 

continuous DO readings 

decreased from early July 

highs of 8.2 mg/L to early 

August lows of 3.5 mg/L, 

with increases in mid to

late August; only one 

hourly reading less than 

4.0 mg/L in July in the 

tailrace monitor, and other 
95

Parameter 2006 2007 2010 2011

nearby river monitors were 

generally 1 to 2 mg/L 

higher

pH Met state water quality 

criteria; within pH range of 

7.4 to 8.0

NA Generally met state water 

quality criteria; fluctuated 

between 7.0 and 8.0, with 

the lowest pH of 6.7 and 

highest of 9.1

Met state water quality 

criteria; pH range of 7.5 to 

8.5

Turbidity NA NA NA Met state water quality 

criteria; observed range of 

3.3 to 26.1 nephelometric 

turbidity units (NTUs)

(state standard ≤40 NTU)

Table 3-11. Summary of water quality data collected in the Muddy Run Pumped Storage Project reservoir, 2010 and 

2011 (Source: Exelon, 2012a; Normandeau and Gomez and Sullivan, 2012p).

Parameter 2010 2011

Water 

temperature

Met state water quality criteria; thermal stratification did 

not occur in the reservoir; surface water temperatures

ranged from 52.2 °F on April 5 to 84.6 °F on July 26; 

98.4-foot-deep water temperatures ranged from 48.2°F 

on April 5 to 84.2°F on July 26

Met state water quality criteria; thermal stratification did 

not occur in the reservoir; surface water temperatures

ranged from 75.2 to 85.5 °F with cooler temperatures in 

August; temperatures at depth ranged from 75.2 to 

85.3°F 

DO Some violations of state water quality criteria; seasonal 

decrease in DO levels from high in April to lows in 

August; strong DO vertical stratification in main 

Some violations of state water quality criteria; DO 

vertical stratification in main reservoir in some locations, 

with DO levels as low as 2.4 mg/L at depth; a weak 
96

Parameter 2010 2011

reservoir with DO less than 5.0 mg/L at depths deeper 

than 25 feet in July and throughout the water column in 

August; no stratification at head of intake canal because 

of mixing of flows at that location; continuous 

monitoring found 70 instantaneous hourly DO values 

less than 4.0 mg/L with most (42 or 60 percent) recorded 

at the cylinder gate (intake) monitor in August when the 

project was in an idle mode; average daily DO value was 

also less than the state standard of 5.0 mg/L on 7 days in 

August and 1 day in September at the cylinder gate 

monitor

inverse DO stratification (higher DO in deeper water and 

lower DO in surface water) observed at head of intake 

canal, likely due to higher oxygenated Conowingo Pond 

water being pumped into the Muddy Run reservoir; 

continuous monitoring found instantaneous hourly DO 

values less than 4.0 mg/L 15 percent of the time between 

July 16 and August 7, with a higher occurrence of lower 

DO levels during the idle mode compared to pumping or 

generating; consistent increase in DO in the intake canal 

during the pumping mode as a result of the introduction 

of higher oxygenated river (Conowingo Pond) water 

pH Met state water quality criteria; pH range of 7.0 to 8.6 Met state water quality criteria; pH range of 7.2 to 8.4

Conductivity NA Conductivity ranged from about 250 to 370 μS/cm in 

July and 220 to 400 μS/cm in August, with a decrease in 

conductivity with the onset of high flows in late-August 

Turbidity NA Met state water quality criteria; observed range of 3.1 to 

26.0 nephelometric turbidity units (NTUs) (state 

standard ≤40 NTU)

Chlorophyll 

a

Values ranged from 0.401 to 20.9 mg/m3 during the 15 

bi-weekly sampling events

NA
97

Conowingo Project 

The Conowingo Project area has an extensive, long-term history of water quality 

sampling associated with the operational monitoring for PBAPS, and operational 

monitoring and prior relicensing studies for the Conowingo Project. These data extend 

back to the 1950s, and parameters of primary concern are water temperature and DO. 

Conowingo Pond is a large temperate reservoir that follows a typical seasonal 

pattern of warming and cooling, with minimum temperatures of 32°F in 

January/February,38 warming during the period of March through July, reaching a 

maximum average high temperature of about 81°F in July/August, and then cooling from 

August through December. Thermal stratification does not occur in Conowingo Pond, 

although during the warmest summer months, bottom temperatures may be a few degrees 

cooler than the surface temperatures in the deeper parts of the reservoir, especially on 

sunny, calm days.

Average surface DO levels show an opposite trend to water temperatures, with 

highest DO levels of nearly 14 mg/L occurring in January/February, and lowest DO 

levels in July/August/September, with the lowest average level of 7 mg/L in August. DO 

levels remain well mixed throughout the water column during much of the year, but DO 

stratification occurs in the deeper parts of the reservoir closer to Conowingo dam during 

the warmer, low-flow summer months. Stratification generally occurs when river flows 

are less than 20,000 cfs and water temperatures are greater than 70°F. The stratification 

usually begins in late June or early July, with low DO levels (<5 mg/L) occurring by mid 

to late July, and most common at depths greater than 30 feet. The deepest portions of the 

pond may approach or become hypoxic (DO <2 mg/L) and even anoxic under certain 

conditions. This DO stratification can persist for up to 60 days depending on river flows

and other weather conditions, with an increase in river flows and the onset of strong 

winds mixing the pond and eliminating stratification. Diurnal variation in DO levels 

occurs in surface waters in Conowingo Pond at depths less than 20 feet, with this 

variation sometimes as great as 5 mg/L. Peak DO levels normally occur in the mid to late 

afternoon as a result of photosynthesis, and reach their low point at dawn as a result of 

plant respiration overnight.

Conowingo Pond water quality directly affects water quality in the tailrace and 

lower Susquehanna River. Exelon’s Station 643, located along the Susquehanna River 

west shore 0.6 mile downstream of the dam and a long-term monitoring station for water 

temperature and DO, is designated as the primary Maryland State standard compliance 

 

38 Conowingo Pond may freeze over in colder winters, but not in all winters, as 

strong northwest winds may act to break up any ice cover that forms. Conowingo Pond 

also receives the heated discharge from PBAPS, which may act to maintain open water 

along the west shore of the reservoir downstream of PBAPS.
98

monitoring location. Water temperature in the tailrace closely reflects the temperatures 

in the pond, with similar seasonal trends and minimum and maximum levels. Because 

the Conowingo generating units withdraw water from the bottom of the reservoir, DO 

levels in the project discharge have been similar to levels at depth (40 to 70-foot depths) 

in the pond. During low-flow, high-temperature periods in the summer, when reservoir 

bottom DO levels approached anoxic conditions, DO levels in the tailrace were 

historically as low as 2 mg/L. However, from 1989 to 1991, Exelon installed aeration 

(turbine venting) on all the Francis units (Units 1 through 7). Prior to installation of 

aeration, in some years, hourly DO levels were less than 5 mg/L up to 40 percent of the 

time. Following installation of aeration, hourly DO readings were less than 5 mg/L only 

0.03 percent of the time (from 1989 to 2007), and no readings were less than 4.3 mg/L. 

Exelon also installed aerating turbine runners in two Francis units in 2005 and 2008,

further enhancing its ability to provide additional aeration in the tailrace.

Other water quality data were collected by USGS in the discharge from Unit 8 

from 1978 to 2000, and a subset of those data are summarized in table 3-12. 

Table 3-12. Selected water quality parameters recorded by USGS at the Unit 8 

discharge from January 1978 to June 2000 (Source: Exelon, 2012b).

Parameter Minimum Mean Maximum

Water temperature (°F) 32.0 56.2 87.8

Turbidity (nephelometric 

turbidity units)

0 13 410

Conductivity (μS/cm) 110 218 420

DO (mg/L) 1.4 10.4 17.8

pH 6.0 7.5 8.8

Alkalinity (mg/L CaCO3) 8 40 82

Total dissolved solids 

(TDS)(mg/L)

53 120 246

TDS loading (tons/day) 490 29,332 99,500

Total suspended solids 

(mg/L)

1 45 1200

Total suspended solids

loading (tons/day)

12 32,230 2,020,000

Dissolved nitrogen 

(mg/L N)

0.4 1.8 6.6

Total phosphorus (mg/L P) 0.010 0.072 1.500
99

Recent Water Quality Studies

Exelon conducted additional studies in 2010 to better understand water 

temperature, DO, and other water quality parameters upstream and downstream of the 

project, and to provide information for project relicensing. Sampling occurred in both 

Conowingo Pond and the tailrace from April through October, and focused on water 

temperature, DO, pH, turbidity, and fecal coliform bacteria. Conowingo Pond sampling 

confirmed historical observations of the absence of thermal stratification in the pond, 

although small differences in temperature (less than 4°F) were observed between the 

surface and bottom in some locations. 

The 2010 sampling also showed that, similar to historical data, DO stratification 

occurs in Conowingo Pond during July and August, with DO levels less than 2 mg/L in 

the deeper locations of the pond. Figure 3-11 shows the DO profiles taken immediately 

upstream of Conowingo dam from July through September 2010. These profiles show 

the summertime stratification but also show that DO levels were below 4 and 5 mg/L (the 

state standards) from surface to bottom during many weeks of sampling. Exelon also 

reported that during those weeks, sampling stations upriver in Conowingo Pond showed 

stratification, but this stratification broke down in the lower pond just upstream of the 

dam. The water column was being mixed in the lower pond, and the mixing of the lower 

DO and higher DO waters resulted in an overall lower DO profile from top to bottom. 

Stratification begins to break down throughout the pond in September, and by earlyOctober stratification has disappeared and DO levels are above 8 to 9 mg/L throughout 

the water column.

Turbidity and pH data in 2010 (collected at midpoint stations in Conowingo Pond) 

remained within the ranges observed in long-term sampling at Conowingo dam (see 

table 3-12). Turbidity ranged from 1.2 to 146.5 NTUs, and pH ranged from 7.0 to 8.9. 

Fecal coliform sampling in Conowingo Pond found generally low levels during 

the April through October sampling period. The Pennsylvania state standard for 

swimming (full body contact) is no greater than 200 colonies/100 milliliters, and only 

five samples out of a total of 28 samples collected in the Pennsylvania part of Conowingo 

Pond in 2010 had fecal coliform levels greater than the state standard, one in the 

swimming season (May through September) and the remainder in October. Similarly, in 

the Maryland portion of Conowingo Pond, only three of 28 samples had fecal coliform 

levels greater than 200 colonies/100 milliliters, all in October.
100

Figure 3-11. DO profiles taken immediately upstream of Conowingo dam from July 

through September 2010 (Source: Exelon, 2012b).

Conowingo tailrace sampling in April through October 2010 involved monitoring 

water temperature and DO using three methodologies: sampling at specific stations in 

the tailrace, continuous monitoring at the long-term station 643 located 0.6 mile 

downstream of the dam, and discharge boil sampling on 20 dates in July and August. 

Water temperatures were similar to long-term data described above, with peak 

temperatures recorded in late-July and early-August, and then decreasing into October. 

Water temperatures measured at station 643 were representative of those measured 

elsewhere in the tailrace. Maximum water temperatures observed in the discharge boils 
101

generally ranged from 84 to 86°F in July, but reached as high as 90°F. Only small 

differences in temperature were observed among the discharge boils, indicating relatively 

homogeneous temperatures in the overall discharge from the dam.

Tailrace DO levels remained relatively high (met state standards) throughout the 

2010 sampling, likely reflecting the effects of the aeration systems in place on the seven 

Francis generating units. Minimum DO levels exceeded the state standard of 5 mg/L in 

the discharge boils 97.8 percent of the time, with minimum recorded levels of 4.4 to 4.9 

mg/L. At station 643, no DO levels less than 5 mg/L were recorded, and minimum levels 

were generally above 6 mg/L. DO levels at station 643 were usually slightly higher than 

measured at the dam, but the difference was small (less than 1 mg/L) and sampling 

indicated that station 643 monitoring results were representative of conditions in the 

tailrace. Variability in DO levels was observed among the discharge boils across the 

powerhouse, especially between the Francis units that have aeration systems and the 

Kaplan units (8 through 11) that do not have aeration. Differences were also observed 

among the Francis units, sometimes as high as almost 3 mg/L. 

Salinity Encroachment on the Lower Susquehanna River

Exelon investigated the extent of salinity encroachment in the lower Susquehanna 

River (Gomez and Sullivan, 2012b). The Susquehanna River is tidally influenced up to 

about 5 river miles downstream of Conowingo dam (at RM 10). Both Maryland DNR 

and the City of Havre de Grace, Maryland, maintain salinity monitors near the mouth of 

the Susquehanna River and have salinity data available since 1997. The City of Havre de 

Grace monitors salinity at its water supply intake to ensure that salinity levels do not 

exceed federal requirements for drinking water (less than 0.25 parts per thousand [ppt]). 

The Maryland DNR station is closer to the Chesapeake Bay (it is about 0.5 mile 

downstream of the City of Havre de Grace’s station). Salinity levels at both stations are 

relatively low, with median daily salinity levels between 0.005 and 0.02 ppt, although 

occasionally (less than 0.1 percent of the time) they exceed the federal criteria of 

0.25 ppt. Observed salinities ranged from 0.01 to 0.26 ppt at the City monitoring station, 

and from 0.08 to 0.46 ppt at the Maryland DNR monitoring station. Levels varied 

seasonally with salinity generally highest in the fall and late-winter and lowest during 

spring and summer, coinciding with or immediately after the period of highest 

Susquehanna River flows. 

Gomez and Sullivan (2012b) analyzed the relationship of salinity to river flows, 

including short-term project operational changes, as well as the influence of tidal 

fluctuations on salinity. This analysis found that salinity appears to be primarily affected 

by longer term flows (30-, 45-, and 60-day moving average), with short-term flow 

variations having little effect. The highest salinities were observed after extended lowflow periods. Tidal fluctuations also had an effect on salinity during higher salinity 

periods because saltwater is pushed upstream and downstream in the river as the tide rises 

and falls.
102

Sediment Loading

USGS prepared an assessment of the potential sediment trapping capacity of the 

lower Susquehanna River reservoirs, including Conowingo Pond, and the potential 

effects on Chesapeake Bay (Langland, 2009). The details of the USGS study are 

described in section 3.3.1, Geology and Soils, but essentially that study concluded that 

Conowingo Pond may have the capacity to trap additional sediment for another 15 to 30 

years (i.e., up to years 2023 to 2038). Once Conowingo Pond reaches its sediment 

trapping capacity, sediment and nutrient loads delivered to the Chesapeake Bay via the 

Susquehanna River would equal the load delivered into the head of the three lower river 

reservoirs (at Lake Clarke), resulting in an increase in nitrogen, phosphorus, and 

sediment loading into the Bay (Langland, 2009). 

Aquatic Biota

Fishery resources in the lower Susquehanna River are substantial with both an 

important resident warmwater fishery and anadromous and catadromous species that are 

passed upstream and downstream over the mainstem hydroelectric dams. Primary 

warmwater game species in the river include smallmouth bass, largemouth bass, walleye, 

channel catfish, flathead catfish (a recent introduction), and panfish species such as 

redbreast sunfish, bluegill, black and white crappie, and pumpkinseed. Other common 

species include gizzard shad, quillback, spotfin shiner, other shiners, and common carp. 

Juvenile gizzard shad and the shiners serve as forage species for game species. 

Each project reservoir has substantially different characteristics and aquatic 

habitat. Lake Frederic is about 3.5 miles long with about 29 miles of total shoreline

within the York Haven project boundary, including the shoreline of the islands in Lake

Frederic. The maximum depth of Lake Frederic is about 18 feet and the mean depth is

about 6 feet. At the normal water surface elevation of 277.86 feet, Lake Frederic has

a surface area of 2,218 acres. The normal drawdown is about 1.1 feet. Lake Frederic has 

a substrate of primarily bedrock, boulder, cobble, and gravel with limited areas of finer 

substrates (sand, silt, clay). One such area is located in the east channel immediately 

upstream of east channel dam, and has one of the few dense stands of SAV in the 

reservoir. Two other areas of SAV are located along the shorelines of Hill and Shelley 

islands.

Muddy Run reservoir has a maximum depth of about 100 feet, a surface area of 

892 acres at elevation 520 feet, and 471 acres at the maximum drawdown elevation 

(470 feet). The arm of the reservoir that is Recreation Lake has a total area of about 100 

acres and is maintained at a constant elevation of 520 feet for recreational purposes. 

Aquatic habitat in the power reservoir consists of a wide and gently sloping nonvegetated shoreline that is subject to large daily and weekly water level fluctuations (up 

to 50 feet on a weekly basis). Substrates are primarily unweathered bedrock covered in 

places with fragmented weathered bedrock, colluvium, and alluvium. Bedrock 
103

outcroppings and overhangs also occur along the shoreline littoral areas. Little SAV 

occurs within Muddy Run reservoir because of the constantly fluctuating water levels.

Conowingo Pond extends 14 miles upstream from Conowingo dam to the lower 

end of the Holtwood Project tailrace. The Conowingo Pond normal maximum elevation 

is 109.2 feet, resulting in a surface area of about 8,500 acres and a maximum depth of 

about 100 feet. Normal drawdown is about 2 feet, although it may reach 3 feet and 

greater during brief periods, but generally not during the summer recreation season. The 

Conowingo Pond shoreline is relatively steep, but through the years the pond has 

substantially filled in with sediment (except in the more upstream riverine, bedrock 

dominated reach), so the substrate in a large part of the pond is now primarily sand, silt, 

and gravel with several areas of dense SAV along the shoreline. An estimated 312 acres 

of SAV occurs within Conowingo Pond at full reservoir elevation, and that acreage 

substantially declines at elevations lower than 106 feet. The largest areas of SAV occur 

along the east shoreline of Conowingo Pond across from the PBAPS, in shallow areas 

that have filled over the years. Five SAV species were identified as dominant within 

Conowingo Pond: Eurasian watermilfoil (Myriophyllum spicatum), hydrilla (Hydrilla 

verticillata), water stargrass (Heteranthera dubia), Canadian waterweed (Elodea 

canadensis), and coontail (Ceratophyllum demersum). Hydrilla, an invasive species, 

however, dominates SAV beds within the pond. Exelon also investigated SAV 

downstream of Conowingo dam in 2010 (URS and Gomez and Sullivan Engineers, 

2012d). That study found that SAV communities were primarily located in the lower 

portion of the reach below Conowingo dam in areas with fine-grained substrates and 

lower velocities. The upper portion closer to the dam with its higher water velocities and 

primarily bedrock/boulder substrate contains little or no SAV growth. Four SAV species 

were identified downstream of Conowingo: Eurasian watermilfoil, hydrilla, water 

stargrass, and wild celery (Vallisneria americana); Eurasian watermilfoil dominates SAV 

beds, covering more than 95 percent of the area occupied by SAV beds.

The Conowingo Pond and the Muddy Run Recreation Lake support an active boat 

and shoreline sport fishery for resident species, and fishing also occurs in both project 

tailwaters, from the shoreline and by boat. The tailrace fishery downstream of 

Conowingo, however, is more intense than in the Muddy Run tailrace. Muddy Run 

reservoir contains essentially the same species composition as Conowingo Pond, via the 

pumping of eggs, larvae, and other life stages from Conowingo Pond. Exelon reports that 

the fish standing crop is higher than many conventional reservoirs, but carp dominated 

the overall standing crop estimate (69 percent), with walleye, smallmouth bass, white 

crappie and channel catfish comprising 12.8 percent of the mean standing crop. Muddy 

Run reservoir is closed to fishing. However, the Recreation Lake is open to boat and 

shoreline fishing and is stocked annually with rainbow trout. Other species (walleye, 

tiger muskellunge, and channel catfish) have been stocked over the years.

There has been an active program for restoring anadromous fish populations to the 

Susquehanna River for the past 35 years or more. Historically, the river supported large 
104

runs of American shad, river herring (blueback herring and alewife), hickory shad, as 

well as the catadromous American eel. These populations declined in the late 1800s and 

early 1900s because of the construction of canal feeder dams, overfishing, water 

pollution, and eventually the construction of the hydroelectric dams between 1904 and 

1928. The York Haven Project at RM 55 was the first hydroelectric dam on the river, 

having been constructed in 1904. The dam, however, is a low-head structure from 6 to 

22 feet high, and may have been partially passable by shad during higher flow periods. 

Holtwood dam was constructed in 1910 at RM 25, and at 55 feet high, totally blocked 

upstream fish migration. Two fishways were constructed at Holtwood at the time of its 

initial construction—a rock ramp type fishway on the west shore of the bypassed reach, 

and a pool-and-weir type fishway on the east shore of the tailrace. Neither fishway 

reportedly ever passed shad successfully, but the rock ramp fishway did pass some 

American eel, although the numbers are not known. In 1928, the 95-foot-high 

Conowingo dam was constructed at RM 10 without fish passage and became the 

downstream-most obstruction to upstream fish migration on the river.

Modern anadromous fish restoration efforts on the Susquehanna River began in 

the 1950s and 1960s with a number of feasibility studies, followed by the construction of 

a trap and truck facility (the west fish lift) at Conowingo dam in 1972, the initiation of 

fertilized shad egg stocking in the basin, the construction of a shad hatchery by 

Pennsylvania FBC in the mid-1970s, and the total closure of the shad fishery in the 

Susquehanna River and upper Chesapeake Bay by the state of Maryland in 1980. The 

number of shad returning to the river increased through the years, and by 1991 a new fish 

lift (east fish lift) was constructed at the Conowingo Project, followed by new fish lifts at 

the Holtwood and Safe Harbor projects in 1997. The York Haven Project east channel 

vertical slot fishway became operational in 2000. 

The Holtwood Project fish lifts (tailrace and spillway) were renovated as part of 

the expansion of the Holtwood Project, which includes the addition of a new powerhouse 

and 88.3 MW of generating capacity. To improve migratory fish passage at the project, 

PPL: (1) modified the existing spillway fish lift, (2) rerouted the discharge of Unit 1 in 

the existing powerhouse to improve attraction to the spillway fish lift, and (3) excavated 

in the project tailrace and Piney Island Channel to improve fish access to the fish lifts. 

These improvements were completed in 2013, and the improved fish passage facilities 

were operational for the first time in 2014. 

Table 3-13 summarizes the passage of American shad at the four lower river 

hydroelectric projects since 1997. Table 3-13 shows that passage success at Holtwood 

has generally been poor, as a percentage of Conowingo shad passage. Generally, higher 

success rates have occurred during years with lower river flows, while lower success 

rates have occurred in years with higher flows. The current fish passage improvements at 

Holtwood should increase the efficiency of the Holtwood fish lifts. Operation in 2014 

showed a small increase in the percentage of shad lifted at Holtwood, but not a 

substantial improvement because the overall number of shad in the Susquehanna River 

was the lowest since volitional passage was established in 1997. Safe Harbor Project 
105

passage has generally been excellent, with a relatively high percentage of the fish passed 

at Holtwood also passed at Safe Harbor. Lake Aldred, which backwaters into the Safe 

Harbor tailrace is only about 7 miles long, and the design of the Safe Harbor fish lift, 

along with the usual lack of spillage during the fish migration season, allows migrating 

fish to more easily locate the Safe Harbor fish lift. Only low numbers of shad typically 

are counted at the York Haven east channel fishway (table 3-13). However, the river 

reach from Safe Harbor to York Haven is about 22 miles, including about 10 miles of 

Lake Clarke and 12 miles of free-flowing river that includes habitat suitable for shad 

spawning. Not all shad passing Safe Harbor would need to pass York Haven if they 

spawn downstream of York Haven, and, as a result, fish counts at the east channel

fishway do not indicate the actual efficiency of the fishway.

Table 3-13. Summary of American shad passage on the Susquehanna River, 1997–2014

(Source: Pennsylvania FBC, 2014).

Year Conowingoa Holtwood Safe Harbor York Haven

1997 90,971 28,063 20,828 --

1998 39,904 8,235 6,054 --

1999 69,712 34,702 34,150 --

2000 153,546 29,421 21,079 4,675

2001 193,574 109,976 89,816 16,200

2002 108,001 17,522 11,705 1,555

2003 125,135 25,254 16,646 2,536

2004 109,360 3,428 2,109 219

2005 68,926 34,156 25,425 1,772

2006 56,899 35,968 24,929 1,913

2007 25,464 10,338 7,215 192

2008 19,914 2,795 1,252 21

2009 29,272 10,896 7,994 402

2010 37,757 16,472 12,706 907

2011 20,571b 21 8 0

2012 22,143 4,238 3,089 224

2013 12,733 2,503 1,927 202

2014 10,425 2,528 1,336 8
106

a Passage numbers are for the east fish lift, which releases fish into Conowingo Pond. 

The west fish lift is operated to collect shad for hatchery egg supply, and for other 

experimental purposes.

b In 2011, Conowingo fish passage operations were terminated earlier than normal 

because construction at Holtwood dam prevented successful operation of the fish lifts. 

Therefore, all upstream fish lifts were also shut down after only brief operation.

Few other anadromous species currently pass upstream through the lower 

Susquehanna projects. Table 3-14 provides passage data for the other anadromous 

species and the gizzard shad, which is a non-anadromous migratory species that moves 

upstream from Chesapeake Bay to spawn in the spring. All the lower Susquehanna River 

reservoirs also contain landlocked gizzard shad populations, so fish passage counts at 

Holtwood, Safe Harbor, and York Haven may also reflect individuals from those 

populations. The peak passage of river herring occurred at Conowingo in 1997 and 2001, 

when about 243,000 herring passed in 1997 and 285,000 herring passed in 2001. During 

those same years, only about 1,000 to 1,300 herring passed the Holtwood Project, less 

than 1 percent of the number passed at Conowingo, with less than 1,000 herring reaching 

Safe Harbor in both years. The highest alewife passage (7,458) occurred in 2001. Since 

2003, the number of blueback herring and alewife passed at Conowingo has been less 

than 1,000 fish, with few or no herring and alewife recorded in some years. Since 2003, 

only sporadic herring and alewife passage has occurred at upriver dams with no herring 

or alewife passage recorded at York Haven since 2002. Only occasional hickory shad 

have been passed at Conowingo since 1997, with essentially none appearing at upriver 

dams. Small numbers of striped bass have been lifted at Conowingo dam (typically in the 

hundreds of fish per year), and a few of those have been passed at upriver dams, with a 

few striped bass consistently recorded at York Haven dam. 

Catadromous American eel elvers39 occur at the base of Conowingo dam, and a 

few may be passed upstream at Conowingo through the fish lift, although fish lifts are 

generally not effective in passing elvers, which are also difficult to quantify because they 

are small enough to pass through crowding devices and screens. Some of the eels that 

manage to pass Conowingo may appear at Holtwood and the upstream dams. Both FWS 

and Exelon have been collecting eels downstream of Conowingo dam since 2005, to 

assess the spatial distribution and size characteristics of American eels in the Conowingo 

tailrace, to assist in determining the feasibility and potential locations for upstream eel 

passage facilities. These studies used both experimental eel ramps and eel pots on the 

west shoreline of the tailrace near the west fish lift, as well as in locations near the east 

 

39 Elvers are juvenile American eel that ascend the river during the spring and 

summer months.
107

fish lift and in the spillway. Catches have been variable, ranging from total annual 

catches typically in the hundreds up to a maximum of 85,000 eels in eel ramps near the 

west fish lift in 2011. FWS collected more than 400,000 eels in 2013.40 Eels collected 

by the ramps have ranged in length from 76 to 225 millimeters (about 3 to 9 inches) and 

are likely primarily elvers, while eels collected in the eel pots are generally larger, up to 

770 millimeters (30 inches) in length, indicating the presence of older age classes that are 

residents to the lower river downstream of Conowingo dam.

Table 3-14. Summary of other anadromous fish (not including American shad) and 

gizzard shad passage on the Susquehanna River, 1997–2014 (Source: 

Pennsylvania FBC, 2014; SRAFRC annual reports).

Year Conowingoa Holtwood Safe Harbor York Haven

1997

Blueback herring 242,815 1,042 534 -

Alewife 63 0 1 -

Gizzard shad 344,332 167,916 116,158 -

Hickory shad 0 1 0 -

Striped bass 1,015 4 0 -

1998

Blueback herring 700 62 16 -

Alewife 6 0 4 -

Gizzard shad 654,575 138,713 102,702 -

Hickory shad 0 0 0 -

Striped bass 1,467 116 12 -

1999b NA NA NA NA

2000

Blueback herring 14,963 27 159 0

Alewife 2 0 657 2

Gizzard shad 317,753 141,176 120,696 72,972

Hickory shad 0 0 0 0

Striped bass 802 4 3 12

 

40 Email from Steve Minkkinen, FWS, Annapolis, MD, to Seth Johnson, 

Earthjustice, Washington, D.C. December 11, 2013.
108

Year Conowingoa Holtwood Safe Harbor York Haven

2001

Blueback herring 284,921 1,300 710 4

Alewife 7,458 1 13 0

Gizzard shad 429,461 188,098 151,873 89,272

Hickory shad 0 0 0 0

Striped bass 543 4 5 8

2002

Blueback herring 2,037 13 0 0

Alewife 74 0 1 1

Gizzard shad 513,794 107,600 98,137 60,247

Hickory shad 6 0 0 0

Striped bass 913 7 1 10

2003

Blueback herring 530 3 0 0

Alewife 21 2 0 0

Gizzard shad 459,634 145,732 110,652 112,000

Hickory shad 0 0 0 0

Striped bass 267 2 1 26

2004

Blueback herring 101 0 0 0

Alewife 89 2 1 0

Gizzard shad 602,677 170,411 127,628 84,234

Hickory shad 0 0 0 0

Striped bass 391 3 0 2

2005

Blueback herring 4 0 0 0

Alewife 0 0 0 0

Gizzard shad 305,100 52,708 44,331 11,969

Hickory shad 0 0 0 0

Striped bass 49 0 11 6

2006
109

Year Conowingoa Holtwood Safe Harbor York Haven

Blueback herring 0 0 0 0

Alewife 0 0 0 0

Gizzard shad 655,990 227,443 179,150 164,869

Hickory shad 4 0 0 0

Striped bass 75 0 8 5

2007

Blueback herring 460 0 0 0

Alewife 429 0 0 0

Gizzard shad 508,627 121,927 84,466 21,843

Hickory shad 0 0 0 0

Striped bass 127 3 2 0

2008

Blueback herring 1 0 0 0

Alewife 4 0 0 0

Gizzard shad 919,975 234,967 163,354 15,930

Hickory shad 0 0 0 0

Striped bass 20 0 3 5

2009

Blueback herring 71 0 0 0

Alewife 160 0 0 0

Gizzard shad 876,412 228,370 170,686 76,995

Hickory shad 0 0 0 0

Striped bass 66 0 0 7

2010

Blueback herring 4 0 0 0

Alewife 1 0 0 0

Gizzard shad 813,429 182,929 130,482 48,152

Hickory shad 0 0 0 0

Striped bass 34 2 5 6

2011 c

Blueback herring 17 - - -
110

Year Conowingoa Holtwood Safe Harbor York Haven

Alewife 2 - - -

Gizzard shad 257,522 - - -

Hickory shad 20 - - -

Striped bass 21 - - -

2012

Blueback herring 24 0 0 0

Alewife 27 0 0 0

Gizzard shad 1,064,708 211,478 136,369 86,515

Hickory shad 0 0 0 0

Striped bass 122 2 1 5

2013

Blueback herring 7 0 0 0

Alewife 0 8 0 0

Gizzard shad 1,076,048 418,310 348,753 106,395

Hickory shad 1 0 0 0

Striped bass 200 3 3 7

2014

Blueback herring 6 0 0 NAb

Alewife 130 2 0 NA

Gizzard shad 1,170,200 297,522 216,826 NA

Hickory shad 2 0 0 NA

Striped bass 110 1 6 NA a Passage numbers are for the east fish lift, which releases fish into Conowingo Pond. 

The west fish lift is operated to collect shad for hatchery egg supply, and for other 

experimental purposes.

b Data were not available from the Pennsylvania FBC website.

c In 2011, Conowingo fish passage operations were terminated earlier than normal 

because construction at Holtwood dam prevented successful operation of the fish lifts. 

Therefore, all upstream fish lifts were also shut down.
111

Several other species have successfully used the fish lifts in the lower 

Susquehanna River, including substantial numbers of game species such as walleye and 

smallmouth bass. In a review of resident fish passage from 1997 to 2007, 49 fish species 

were recorded in the fish passage facilities of the lower Susquehanna River 

(Shiels, 2007). The species that dominates fish passage through the lower river dams is 

the gizzard shad. The gizzard shad, however, is not considered a game or sport species, 

does not support a directed fishery, and is considered by many to be useful only as a 

forage species for other fish during its juvenile life stage, because of its large adult size. 

The number of gizzard shad annually passing the lower river dams typically numbers in 

the hundreds of thousands, reaching over a million fish at Conowingo in 2012 and 2013 

(see table 3-14). Shiels (2007) reported that gizzard shad comprised about 75 percent of 

all fish passed over the lower river dams from 1997 to 2007. While the number of 

gizzard shad passed at each upstream dam decreases substantially between dams, large 

numbers of gizzard shad are passed annually at York Haven, often exceeding 100,000 

fish, as in 2003, 2006, and 2013.

Engineered downstream fish passage facilities have generally not been provided at 

any of the lower Susquehanna River projects. Studies have been conducted at all of the 

projects to assess downstream passage of anadromous clupeids and the American eel. In 

addition, behavioral devices (lights and sound) were tested with shad at the York Haven 

Project, both as a deterrent to prevent turbine passage and as a guidance mechanism to 

move fish toward the forebay sluice gate for safe passage. Downstream passage at York 

Haven occurs via natural spillage over the dam or via the forebay sluice gate in 

combination with lights and sequencing of unit operations. Downstream passage at the 

other projects has generally been via the turbines, where passage survival has been found 

to be relatively high for juvenile anadromous clupeids (particularly at Safe Harbor and 

Conowingo). For example, at Safe Harbor dam, downstream passage survival was 

estimated at 97 percent for juvenile shad and 88 percent for adult shad (RMC

Environmental, 1991; Normandeau, 1998), and at Conowingo dam at 90 to 95 percent for 

juvenile shad and about 90 percent for adult shad (Normandeau and Gomez and Sullivan, 

2012f; 2012i). Some fish may also pass downstream over the project spillways if a highflow event and spillage coincides with the outmigration period. 

Freshwater Mussels

York Haven Project

Strayer and Fetterman (1999) list 14 mussel species from the Susquehanna River 

system. Spoo (2008) reported 13 species from the Susquehanna River system, and the 

Pennsylvania Natural Heritage Program reported seven mussel species from Lancaster 

County in the vicinity of Brunner (Lows) Island and Conewago Creek. Meyer (2010) 

reported an apparent decline in populations of the eastern elliptio in Pennsylvania, 

although it is considered stable throughout most of its north Atlantic slope distribution 

(NatureServe, 2010).
112

A mussel reconnaissance survey was conducted in July 2010 during low-flow 

conditions (6,000 cfs at USGS 01570500 gage at Harrisburg, Pennsylvania) at the York 

Haven Project. Based on substrate conditions, water depth, and velocity, representative 

aquatic habitat types within the project area were searched for live mussels and shells. 

Shoreline and exposed bars were checked for shell material and middens.41 Using results 

from the reconnaissance survey, seven sites were chosen for detailed analysis in four 

areas: main channel 1 (spillway reach), main channel 2 (middle section), main channel 3 

(lower section including the powerhouse area) and the east channel of the river 

(figure 3-12). 

A detailed survey was conducted in August 2010 when discharge was 6,000 to 

7,000 cfs at USGS 01570500 gage at Harrisburg, Pennsylvania. Five species and 56 live 

mussels were collected during 23.4 hours of searching (tables 3-15 and 3-16). An 

additional four species were found only as dead shells. Catch-per-unit-effort (CPUE) 

ranged from 2.7 to 9.3 at three locations, and with an average value of 2.6 for all sites 

combined. The mussel assemblage was dominated by eastern floater which comprised 

58.9 percent of the fauna and was approximately three times more abundant than the 

second most common species, yellow lampmussel. Several small eastern floaters and a 

single juvenile yellow lampshell were collected, which indicates that these species are 

likely recruiting in the area.

 

41 Middens are small collections or piles of mussel shell material, often 

accumulating as a result of river flow patterns.
113

Figure 3-12. Mussel sampling sites located below the York Haven Power Plant, 

Susquehanna River (Source: York Haven Power, 2012a).
114

Table 3-15. Mussel species collected in the Susquehanna River, York Haven Project, 

August 2010 (Source: York Haven Power, 2012a). 

Common Name Scientific Name 

Live Mussels

Shell 

Material Statusa Number

% 

Abundance

Eastern floater Pyganodon 

cataracta

33 58.9 X Not listed

Yellow 

lampmussel 

Lampsilis cariosa 10 17.9 X S3, S4

Eastern elliptio Elliptio complanata 7 12.5 X Not listed

Alewife floater Anodonta implicata 4 7.1 X S3, S4

Creeper Strophitus 

undulatus 

2 3.6 X Not listed

Rainbow mussel Villosa iris X S1

Green floater Lasmigona 

subviridus 

X S2

Susquehanna 

elktoe 

Alasmidonta 

marginata 

X S4

Triangle floater Alasmidonta 

undulata 

X S3, S4

Total live mussels 56 a Status designations are based on Pennsylvania Natural Heritage Program (PNHP, 

2011a) and PNHP (2011b): S1-Criticially imperiled; S2-Imperiled; S3S4-

Vulnerable/apparently secure; and S4-Apparently secure.
115

Table 3-16. Live mussels collected using semi-quantitative methods in the Susquehanna 

River, York Haven Project, August 17 to 18, 2010 (Source: York Haven 

Power, 2012a).

Location

Total 

Search

Time, hours

CPU, 

#/hour Species Number

1-Main Channel tailrace 3.65 0.0 None

2a-Main Channel, LDB 2.00 0.0 None

2b-Main Channel, RDB 0.35 0.0 None

3-Main Channel 1.52 0.0 None

4-Spillway Con 5.25 2.7 Eastern floater 8

Alewife floater 3

Yellow lampmussel 3

5-East Channel DS Bridge 3.20 0.0 None

6-East Channel, US Bridge 2.08 3.4 Eastern floater 5

Yellow lampmussel 2

7-Upper East Channel 3.75 9.3 Eastern floater 20

Eastern elliptio 7

Yellow lampmussel 5

Creeper 2

Alewife floater 1

For the project Area 21.80 2.6 56

Aquatic habitat in the project area consisted mainly of bedrock and boulders, 

which is not particularly suitable for freshwater mussels. No live mussels were found at 

sites 1-3 in the main channel. Virtually all of Site 1 was unsuitable, and the 

unconsolidated substrate between boulders and bedrock outcrops at Sites 2a, 2b, and 3 

was only marginally suitable for mussels. Fourteen mussels representing three species 

were found at Site 4, in the upper reach of the main channel in the project area, which 

consisted mainly of bedrock with only small amounts of gravel. 

No live mussels were found at Site 5 in the lower east channel, which was 

characterized by high velocity water, bedrock, boulders, and only small areas of cobble 

and gravel overlain by sand. Live mussels were collected at Sites 6 and 7, in the mid and 

upper east channel, respectively. Seven live mussels (eastern floater and yellow 

lampmussel) were collected during 2.08 hours of searching at Site 6. Habitat at this 
116

location was more suitable for mussels than at Site 5, and was a shallow pool/slow run 

with a mixture of cobble, gravel, and sand with some bedrock and boulders. Site 7 in the 

upper east channel supported the most abundant assemblage in the project area; 5 species 

and 35 individuals were collected and overall CPUE equaled 9.3. Substrate was a 

mixture of gravel, cobble, and sand with some areas of silt. 

Comparatively small numbers of live native mussels were taken in this semiqualitative survey; therefore it is not possible to provide a thorough analysis of 

population demography or recent recruitment in the York Haven Project area. Based on 

survey results, total shell length for eastern floater ranged from 40-110 millimeters, and 

for yellow lampmussel from 43-98 millimeters. Intermediate sized organisms of both 

species were collected, and presence of comparatively small-sized individuals indicates 

that at least these two species had recruitment in or immediately outside the project area 

within the last several years. No federally listed threatened or endangered mussel species 

were found during this survey. 

Muddy Run Project

Native freshwater mussels were not collected in Muddy Run reservoir or in the 

Susquehanna River below the dam. No federally listed threatened or endangered mussel 

species have been reported within the project boundary.

Conowingo Project

Marshall (1930) surveyed for mussels in September 1929, approximately 1 year 

after Conowingo dam was constructed. He reported two live eastern elliptio, as well as 

yellow lampmussel (one shell) and eastern lampmussel (Lampsilis radiata) (four shells). 

Ashton (2009) described results from three surveys conducted during 2008 and 2009. 

Methods included benthic trawling and SCUBA diving by personnel from Marshall 

University, West Virginia, and collections by personnel from Maryland DNR’s 

Monitoring and Non-tidal Assessment Division. Live individuals and dead shells of six 

species were found in 2008 and 2009, including eastern elliptio, alewife floater, eastern 

floater, tidewater mucket, northern lance (Elliptio fisheriana), and creeper. Ashton 

(2009) also reported that eastern lampmussel was collected in 1990 and 1998 by 

personnel of Maryland DNR’s Natural Heritage Program. In 2010, Ashton conducted 

mainly timed-snorkel searches in suitable mussel habitat downstream of Conowingo dam 

(Ashton, 2011). He collected dead shells of northern lance (Elliptio fisheriana), not taken 

in his previous two surveys, and was the first to report the presence of the invasive zebra 

mussel (Dreissena polymorpha) in the project area. 

Contact with nine museums yielded few historical records for mussels in the 

project area. Three records from the National Museum of Natural History in 

Washington, D.C., were from upper Chesapeake Bay approximately 8 to 10 miles 

downstream of the study reach; one was for tidewater mucket and two were for eastern 

lampmussel. The Canadian Museum of Nature had two records from the Susquehanna 

River near the mouth of Deer Creek. One is for eastern elliptio and the other is for 
117

Anodonta fluviatilis, a taxon that is no longer recognized. It is likely this was the eastern 

floater (Pyganodon cataracta) based on synonymies in Strayer and Jirka (1997). Two 

additional records at the Canadian Museum of Nature were for eastern elliptio and the 

eastern lampmussel. The exact location of these records was not clear, although they 

were likely from downriver of the project area. 

In 2010 and 2012, semi-quantitative (timed searches) mussel surveys were 

conducted in the Susquehanna River below Conowingo dam (figure 3-13). The 2010 

studies were conducted by Normandeau and Gomez and Sullivan (2012e), and the 2012 

studies were conducted by Biodrawversity and Gomez and Sullivan (2012). A total of 

128 sites were sampled using semi-quantitative methods during the 2 years. In 2010, 

locations likely to support live mussels were sampled; the 2012 study was designed to 

include areas not covered during the first survey. Semi-quantitative collections were 

obtained by wading, snorkeling, or SCUBA diving. During the 2012 survey, notes were 

made on water depth, substrate type, and flow conditions. 

Five species and 6,301 native mussels were collected in 2010 and 2012 using 

semi-quantitative methods (table 3-17). For all species and sites combined, CPUE ranged 

from 0 to 612 (mean = 64.1, standard deviation = 94.5). Most of the sites with the 

greatest number of mussels were within or near tidal areas at the downstream end of the 

study reach. CPUE values of less than 5.0 were recorded at 21.1 percent of the sites. 

Although sites with comparatively few mussels were found throughout the area, most 

were located near the mouth of Octoraro Creek, near Bird Island, Rowland Island, or in 

the back channel of Mud Island at the upstream end of the study reach. Overall, the 

fauna was strongly dominated by eastern elliptio which comprised 96.3 percent of the 

assemblage and was found at 93.7 percent of the sites. Average CPUE for this species 

was 61.7 (standard deviation = 91.8). Eastern elliptio was particularly abundant in the 

downstream portion of the project area, mainly in tidal areas. The remaining four species 

together comprised less than 4 percent of the fauna; average CPUE for each ranged from 

1.55 (standard deviation = 2.99) to 0.10 (standard deviation = 0.48). A single shell of the 

creeper was found in the project area by Maryland DNR in 2010. 

No federally listed threatened or endangered mussel species were found during 

this survey. In the state of Maryland, alewife floater was listed as S3, eastern lampmussel 

was listed at S1 and S2, and tidewater mucket was listed as SU (table 3-17).
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Figure 3-13. Mussel sampling sites located below Conowingo dam, Susquehanna 

River.
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Table 3-17. Freshwater mussels collected in the Conowingo Project area (Source: 

Biodrawversity Inc. and Gomez and Sullivan Engineers, 2012). 

Common 

Name Species

Percent 

Abundance

Frequency of

Occurrence

CPUE

Mean SD Statusa

Eastern Elliptio Elliptio 

complanata

96.3 93.8 61.70 91.8

Alewife Floater Anodonta 

implicata

2.1 35.9 1.55 2.99 S3

Eastern Floater Pyganodon 

cataracta

1.1 22.7 0.47 1.11

Tidewater 

Mucket 

Leptodea 

ochracea

0.4 17.2 0.25 0.69 SU

Eastern 

Lampmussel 

Lampsilis 

radiata

0.1 5.5 0.10 0.48 S1, S2

Notes: Results of two similarly conducted surveys were combined: Normandeau 

Associates (August 9– September 3, 2010), and Biodrawversity (July 16-19, 

2012). A total of 6,301 live mussels were collected using semi-quantitative 

methods at 128 sites.

a Status from the Maryland Natural Heritage Program (2010): S1-Criticially imperiled; 

S2-Imperiled; S3-Vulnerable; and SU - Possibly rare in Maryland, but of uncertain 

status.

A total of 117 live mussels were collected in the 66 quadrat samples collected 

during both study years. The fauna was dominated by eastern elliptio (95.7 percent), and 

equal numbers of alewife floater and eastern floater (both 3.1 percent). Mean total 

density ranged from a low of 0.11 (99 percent confidence interval: -0.07 to 0.29) to a 

high of 4.26 (99 percent confidence interval: 1.39 to 7.15). The highest densities were 

obtained at two locations in the secondary channel of McGibney Island. Mussels were 

more likely to be found in quadrats where silt, sand, and gravel comprised 30 to 80 

percent of total substrate. Population estimates for all species combined for the 450 m

2

plots ranged from 50 mussels (90 percent confidence interval = -32 to 132 mussels) to 

1,920 mussels (90 percent confidence interval = 623 to 3,217 mussels). 

The mussel fauna in the project area was characterized by dominance (>95

percent) of a single species (eastern elliptio), and fewer numbers of five other species. 

Physical conditions of substrate and water velocity were patchy throughout the project 

area, and this likely caused the high variability in overall CPUE, which ranged from at or 

near 0 to over 600. Although it can be difficult to assess recent recruitment of these long-
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lived organisms over a short sampling period, few small individuals of any species were 

taken in either type of sampling. Based on quantitative sampling, 95 percent of eastern 

elliptio measured 60 to 130 mm and only two were less than 40 mm total shell length. 

Only a single (0.01 percent of the total collection) juvenile-sized (32.0 mm) eastern 

floater was collected using semi-quantitative methods.

The distribution of freshwater mussels varies with distance from Conowingo dam, 

proximity to tidal influence, substrate conditions, and hydraulic conditions. Results 

indicate that water velocity, shear stress, and substrate type affect mussel distribution. In 

the project area, mussel species were either very uncommon or not collected in habitats 

prone to frequent dewatering, areas with poor substrate, or areas subjected to high shear 

stress. Mussels were more prevalent where modeled shear stress was relatively low. 

Areas of highest CPUE observed in this study were typically along the east side of the 

river in the downstream half of the project area, where flow is considerably less than near 

the dam in the upstream half of the project area. In addition to this overall trend, the 

several sites with highest CPUE values in the project area also occurred in zones of local 

flow refugia, where stream flow models showed shear stress to be lower than in 

immediate surrounding areas. These results are similar to findings from other mussel 

studies from other parts of the country (Layzer and Madison, 1995; Strayer, 1999;

Morales et al., 2006; Allen and Vaughn, 2010).

Invasive Species

York Haven Project

Asian clams (Corbicula sp.) were collected downriver of the York Haven Project

as part of macroinvertebrate studies. Although zebra mussels have been found in the 

upper Susquehanna River drainage (Kazyak et al., 2005), none were found in Lake 

Frederic or downriver of the project area. 

Muddy Run Project

Dead zebra mussel shells were observed along the shore of Muddy Run reservoir 

in November 2008, approximately 1 month after they were discovered in

Conowingo Pond. 

Conowingo Project

Zebra mussel veligers were found in 2009 and 2010 in the intake canal at PBAPS 

on the west bank of Conowingo Pond in Delta, Pennsylvania, during Exelon’s ongoing 

zebra mussel monitoring program at PBAPS. Zebra mussels were found at eight sites

downstream of Conowingo dam; three were close to the dam, and the remainder were

collected either at the mid- or extreme-lower portion of the project area. Asian clams 

were observed at nearly every site in the project area (Ashton, 2009).
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3.3.2.2 Environmental Effects

Brunner Island Station Cooling Water

The Brunner Island Station, owned by PPL Brunner Island LLC (PPL BI), is 

located 1.5 miles downstream of the York Haven powerhouse on the west side of the 

Susquehanna River. The station is a coal-fired generating station that uses up to 

1,200 cfs of water from the river for cooling when operating at full capacity. Stations 

such as this typically run at a set output, preferably peak or full capacity, to provide 

baseload electricity to the power grid. They are typically operated at that level for a set 

period of time, or run continuously, as needed. On August 6, 2012, PPL BI filed 

comments pertaining to the York Haven Project draft license application with the 

Commission expressing its concerns that, under low-flow conditions, new minimum flow 

requirements could allow the river flow in the vicinity of the Brunner Island Station water 

intake to fall below 1,200 cfs (PPL BI, 2012). PPL BI’s concern is that, during low-flow 

conditions when flows fall to or below 1,200 cfs, large areas of exposed rock can cause 

debris to affect water flow patterns in the natural channel upstream of, and in the vicinity 

of, the Brunner Island Station water intake.

In the final license application, York Haven Power stated that it did not anticipate 

changing its flow releases, and that it would consult with PPL BI if that changed. York 

Haven Power also stated in exhibit B of the license application that it voluntarily releases

1,000 cfs on the west side of the river for the benefit of the Brunner Island cooling water 

intake. Although the Settlement Agreement would change where flows are released from 

York Haven dam and generally reduces the magnitude of the releases at those locations, 

the minimum flows at the project would remain as a continuous minimum flow of 1,000 

cfs and a 2,500 cfs average daily minimum flow (or inflow, if less) downstream of the 

project as currently licensed. Inflow is based on river flows as recorded at the USGS 

gaging station at Harrisburg, Pennsylvania. 

On February 19, 2014, PPL BI filed a Protest and Comments on the Settlement 

Agreement (PPL BI, 2014). PPL BI stated that York Haven Power had not consulted 

with it during the settlement process and reiterated its concerns that the proposed 

minimum flow releases would result in periods of time when river flows downstream of 

the York Haven Project in the vicinity of the Brunner Island Station water intake would 

fall below 1,200 cfs, requiring PPL BI to reduce output at Brunner Island Station 

accordingly. PPL BI also stated that this has happened in the past, resulting in a station 

shutdown, further resulting in fish kills due to thermal changes in the Brunner Island 

Station discharge channel. PPL BI requested that a new license for the project include a 

requirement to release a continuous minimum flow of 1,500 cfs to ensure that Brunner 

Island Station operation is not affected.

On March 4, 2014, York Haven Power filed additional information with the 

Commission to support its proposal and contend that PPL BI’s concerns about the 

proposed operation of the York Haven Project are unfounded. It provided the additional 
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information to demonstrate that York Haven Power is not responsible for any detrimental 

effects on Brunner Island Station due to instream flows (York Haven Power, 2014b).

York Haven cited historical flow data provided in the license application that show

extreme low flows in the range of 2,000 cfs.42 York Haven Power notes that sections 

3.2.1(cc) and 3.2.2 of the Offer of Settlement state that, when inflows are less than 

3,000 cfs, the project (York Haven) would be operated on a run-of-river basis, adding or 

suspending operations at turbines to reflect, to the extent practicable, inflow from 

upstream and without adding or suspending turbine operations to deliberately draw down 

or store water for purposes of generating electricity during particular time periods. As 

such, York Haven Power would have no ability to provide additional flows to ensure that 

Brunner Island had sufficient flows to operate at full capacity.

York Haven Power suggests that PPL BI did not understand York Haven Power’s 

proposed minimum flow releases related to the proposed nature-like fishway and the 

reduced flows for the east channel fishway. A flow of 200 cfs would be diverted from 

the east channel fishway and passed through the nature-like fishway. Because the naturelike fishway is farther downstream of the east channel on the west shore of the bypassed 

reach, the flows passing downstream of the project would be distributed in a similar 

pattern to existing releases. York Haven Power expects that the result would be at least 

as favorable, if not more favorable flow conditions for operation of the Brunner Island 

station, than what is currently occurring.

In response to PPL BI’s concern that the distribution of flows in the vicinity of the 

Brunner Island cooling water intake may affect its ability to receive adequate flows at 

Brunner Island, York Haven Power notes that once the flows pass downstream of the 

York Haven Project, the project has no control over the distribution of flows in the 

natural channel.

With regard to debris in the channel that could hinder flows reaching the Brunner 

Island intake, York Haven Power points to its debris management program, which entails 

the passing of natural debris that accumulates in the forebay following notification to 

PPL BI that debris would be released. Any other debris passes over the east channel and 

main dams without being handled by York Haven Power. York Haven Power states that 

it has no control over the debris or where it may accumulate downstream of the project.

Our Analysis

Under the terms of the Settlement Agreement, the York Haven Project would 

operate under run-of-river operation during extreme low-flow periods, and would 

therefore have no ability or responsibility to provide supplemental flows to enable the 

Brunner Island station to operate at full capacity under such flow conditions. The 

Settlement Agreement would change where flows are released from York Haven dam and 

 

42 The actual minimum value from the record was 2,066 cfs.
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generally reduces the magnitude of the releases at those locations, but the minimum flows 

at the project would remain as a continuous minimum flow of 1,000 cfs and a 2,500 cfs 

average daily minimum flow (or inflow, if less) downstream of the project as currently 

licensed. Thus, these changes would not be noticed at Brunner Island. Further, York 

Haven Power would provide PPL BI with advanced notice when debris is going to be 

manually passed downstream, and York Haven Power has no control over the debris once 

it passes downstream. 

Competing Water Withdrawals within Conowingo Pond

There are several entities that draw water from the Conowingo Pond as discussed 

in section 3.3.2.1, Water Resources, Affected Environment, some of which are 

consumptive uses; others return water to Conowingo Pond. Although the current license 

allows Exelon to operate Conowingo Pond between elevation 101.2 feet and 110.2 feet, 

the pond is typically not drawn below elevation 105.2 feet to ensure adequate volume to 

meet the water withdrawals from Muddy Run and PBAPS. The other water withdrawals 

are very small in comparison to the withdrawals from Muddy Run and PBAPS. The 

pond is typically maintained at about elevation 109.2 feet. Exelon proposes to continue 

the current water level management in Conowingo Pond.

Although competing water withdrawals was included as a scoping issue, no 

specific stakeholder concerns were raised in regard to competing withdrawals in response 

to the license application for the Conowingo Project and the proposed project operation.

Our Analysis

The current water level management has provided adequate water supply for the 

existing water withdrawals, and the proposed continuation of this management should 

continue to be adequate.

Downstream Flooding at the Conowingo Project

Flooding downstream of Conowingo dam in the town of Port Deposit, Maryland, 

was raised as an issue during scoping by the mayor of the town. The mayor indicated 

that flooding occurs frequently and that it should be adequately evaluated during scoping 

studies. The mayor also indicated that the relationship between dam releases, 

coordination of those releases with the upriver dams, and flooding should be examined 

and the full range of solutions explored. The mayor also suggested that solutions could 

include better flow anticipation, management, and coordination of releases and 

physical/structural actions to prevent flooding (i.e., flood control doors on the 

underpasses in town and storm drain check valves devices). 

Exelon does not propose any project operational changes in regard to downstream 

flooding, and none of the stakeholders recommended changes in the agency terms and 

conditions or public comments filed with the Commission following the filing of the final 

license application.
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Our Analysis

Exelon conducted a study in 2011 (Gomez and Sullivan, 2012a) using a HECRAS model to evaluate the Conowingo Project’s actual and potential influence on 

downstream flooding at Port Deposit during several flood events (10-, 50-, 100-, and 

500-year floods). Three alternative operating scenarios were investigated for their 

potential to reduce downstream flooding. The first alternative simulated drawing down 

Conowingo Pond prior to arrival of high-flow events. The second alternative simulated 

the effect of targeting lower pond levels during the storm. The third alternative simulated 

using the reservoir storage during the storm peak to reduce downstream flows. 

Additionally, a no-dam scenario was included, which simulated Port Deposit stage time 

series to estimate what conditions would be like if Conowingo dam did not exist.

The study results indicated that none of the alternative operating scenarios 

evaluated would substantially reduce downstream flooding. The first alternative was 

found to have no effect on downstream flooding magnitude and only a slight reduction in 

flooding duration. The second alternative had no considerable effect on flooding 

magnitude or duration (less than 15 minutes). The third alternative negligibly reduced 

flooding magnitudes (less than 0.02 foot) and duration (less than 15 minutes). The nodam scenario had slightly increased (0.00 to 0.08 foot) flooding magnitudes and slightly 

decreased flooding durations, relative to existing conditions.

Based on the study results, Conowingo Project operation has little effect on 

downstream flooding. The three alternatives investigated that were considered to be the 

best possible mitigation alternatives showed negligible or no improvement over existing 

conditions. The storage available in Conowingo Pond is not enough to mitigate even 

relatively small events such as the 10-year flood. The no-dam scenario showed the 

current flooding durations would only be slightly different than if the dam did not exist. 

The study concluded that substantially higher storage capacity would be required in 

Conowingo Pond in order for the project to be a viable flood control mechanism. There 

do not appear to be any operational changes that could be made that would reduce Port 

Deposit flooding for the 10-, 50-, 100-, or 500-year storm events.

Water Quality Effects

York Haven Project

As described in section 3.3.2.1, Water Resources, Affected Environment, water 

quality in the York Haven Project area generally meets state water quality standards, and 

there have been no specific recommendations made by commenting entities regarding 

measures required to protect or enhance water quality. The Settlement Agreement also 

did not include any specific measures to address water quality. 

Our Analysis

Water temperatures exceeded the maximum state standard of 87°F (temperatures 

as high as 93°F were recorded) up to about 19 percent of the time in sampling locations at 
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the head of the project impoundment and at the upstream tip of Shelley Island. This 

indicates that inflows to the project reservoir already exceeded state standards due to 

normal summer warming. Water temperatures recorded in the project tailrace exceeded 

the state standard only about 12 percent of the time. While small localized deviations 

from water quality standards (water temperature and DO) have been reported in parts of 

the reservoir, those deviations are not a result of project operation. The operation of the 

Three Mile Island nuclear station does not appear to have any effect on water 

temperatures or thermal stratification at the project. The station has a closed-loop cooling 

system and does not discharge heated waters to the project reservoir. 

DO levels were below state standards for 4 percent and about 1 percent of the 

sampling observations at only two of the sampling sites--the shoreline of Hill Island and a 

location in the east channel upstream of the dam--respectively. Diurnal fluctuations in 

DO were also observed in the reservoir as a result of the natural 

photosynthesis/respiration cycle, particularly in areas with substantial SAV beds. 

Fluctuations in pH levels in the reservoir also appeared to reflect natural variations. 

Muddy Run Project 

As described in section 3.3.2.1, Water Resources, Affected Environment, waters 

discharged from the project generally meet state standards, although DO levels 

occasionally drop below state standards during the warmer summer months. The Muddy 

Run reservoir does not thermally stratify, but does exhibit DO stratification in the main 

reservoir in some locations, with DO levels as low as 2.4 mg/L at depth. Substantial 

mixing occurs in the reservoir near the head of the intake canal during project operation, 

particularly during pumping operation when Susquehanna River (Conowingo Pond) 

waters are entering the reservoir. In 2011, monitoring at times showed a weak inverse 

DO stratification (higher DO in deeper water and lower DO in surface water) as 

Susquehanna River waters entered the reservoir at depth, under the Muddy Run reservoir 

surface waters that were lower in DO. All other measured parameters met state 

standards. 

Exelon proposes to implement the conditions in the draft certification, which states

that it must maintain state water standards at the project, and requires that it submit a DO 

monitoring plan to Pennsylvania DEP no earlier than November 1, 2027; implement the 

plan; and if violations in state standards occur (fail to meet criteria less than 99 percent of 

the time), submit a plan to Pennsylvania DEP to resolve any DO violations. 

Pennsylvania DEP issued a final certification on June 3, 2014. While Exelon has not 

indicated the final certification represents its proposal, our review of the draft and final 

certifications found that they are nearly identical, and therefore we assume that Exelon’s 

proposal has not changed.

There were no other specific recommendations from stakeholders or agencies 

regarding water quality measures in response to the final license application. However, 

during scoping, questions were raised by FWS about the potential effects of flow 
126

reversals43 in Conowingo Pond associated with Muddy Run pumping operation during 

low-flow conditions, and the possible re-distribution of heated discharges from PBAPS.

Our Analysis

Exelon recorded some instances when DO levels within the Muddy Run reservoir 

and in discharges from the project did not meet state standards (see table 3-10 and 3-11). 

In general, project releases had fewer instances where DO did not meet the state standard

than did the reservoir. The Muddy Run Project discharges into the upper, more riverine 

reach of Conowingo Pond where river velocities are typically strong as a result of 

discharges from the upstream Holtwood Project. This results in immediate mixing of 

Muddy Run discharges with the Susquehanna River flow and would act to quickly raise 

DO levels to above state standards. Based on Exelon’s monitoring studies, and the 

location of the project at the upstream reach of Conowingo Pond, there appears to be no 

need to require measures to further protect or enhance water quality. Nevertheless, the

certification conditions when implemented would ensure that state DO standards are 

maintained.

Regarding the potential for Muddy Run pumping operation to result in flow 

reversals that would draw heated water from the downstream PBAPS in an upstream 

direction toward the Muddy Run Project, Exelon’s studies did not find any instances of 

the PBAPS’ heated discharge reaching as far upstream as the Muddy Run tailrace. 

Conowingo Project

In section 3.3.2.1, Water Resources, Affected Environment, we describe existing 

water quality conditions in both Conowingo Pond and in the river downstream of 

Conowingo dam. Based on many years of monitoring in Conowingo Pond, the pond 

exhibits DO stratification (higher DO levels in near-surface waters and low DO levels at 

depth) resulting in the potential for entrainment of lower DO waters through the lowlevel intakes. This occurred over a period of years until Exelon installed turbine venting 

in Units 1 through 7 between 1989 and 1991, and aerating turbine runners in two of the 

seven Francis units (Units 2 and 5) in 2005 and 2008. As a result of these modifications, 

releases from Conowingo dam now meet state standards nearly 100 percent of the time. 

Water temperature has not been an issue at Conowingo, and normally meets state 

standards, even with the presence of the heated discharge from PBAPS into Conowingo 

Pond. 

Commenting entities did not recommend additional water quality enhancement 

measures at Conowingo, although The Nature Conservancy recommends that project 

 

43 Flow reversals mean that flow patterns in Conowingo Pond may be affected by 

Muddy Run Project pumping such that currents would move upstream toward the project, 

potentially pulling the heated PBAPS discharge upstream or causing a wider distribution 

of heated waters in the pond. 
127

operation not result in violation of water quality standards or non-attainment of water 

quality criteria established for the river and Chesapeake Bay, including the Chesapeake

Bay TMDL. Maryland DOE, in its comments in response to the REA notice, states that it 

is premature to make conclusions as to the effect of the project on water quality, because 

it would fully assess project effects during its review of the certification application.

Our Analysis

For the two water quality parameters that may be typically affected by 

hydroelectric project operation, water temperature and DO, existing project operation 

generally does not exceed state standards. Past violations of state DO standards have 

been eliminated by the addition of turbine venting to seven Francis units and aeration to 

two of the seven Francis units. While comments were filed regarding the effects of the 

project on nutrients and sediment loading (discussed in the following section), there 

appears to be no need for further measures to protect or enhance water temperature and 

DO at the project.

Sediment and Nutrient Loading 

Sediment transport in the Susquehanna River and the effects of the presence of the 

lower river hydropower reservoirs on that transport are of concern to many stakeholders. 

This is primarily an issue for the Conowingo Project, because it has the largest and 

deepest reservoir on the lower river, and the greatest capacity for sediment storage. The 

York Haven Project reservoir has minimal storage capacity, because of its small size and 

shallow depth. The Muddy Run Project, because it is an off-stream pumped storage 

reservoir, also has minimal effect on sediment transport or storage in the river. Sediment 

transport is discussed in detail in section 3.3.1, Geology and Soils. 

Sediment transported by the river is also rich in nutrients (nitrogen and 

phosphorus). With the Susquehanna River being the largest source of freshwater to 

Chesapeake Bay, it is also the largest source of nutrients, contributing about 70 percent of 

the total nitrogen and 55 percent of the total phosphorus (Smullen et al., 1982, as cited by 

Cheng et al., 2013). These nutrients and organic matter in the sediment support the 

growth of phytoplankton, algae, and aquatic plants, but if high nutrient loading occurs, 

this may enhance eutrophication and result in hypoxia (the depletion of DO in the water 

column). High turbidity levels associated with high sediment loads may also block 

sunlight in the water column, adversely affecting plant photosynthesis and the production 

of DO. As we previously described, EPA has set a TMDL for Chesapeake Bay with total 

watershed limits on the contribution of nitrogen, phosphorus, and sediment to the Bay. 

The TMDL calls for a reduction in that loading from current levels. 

Exelon proposes a sediment management plan to control sediment from project 

lands, to identify benchmarks for actions needed to address sediment issues that would 

affect project operation, and it would conduct a bathymetric survey every 5 years to track 

depositional patterns in the pond. EPA, Maryland DNR, SRBC, NMFS, Chesapeake Bay 

Foundation, Stewards of the Lower Susquehanna, Inc., Midshore Riverkeeper’s 
128

Conservancy, Inc., and the Clean Chesapeake Coalition state that Exelon’s proposed 

management plans are not ready for analysis without an understanding of the sedimentrelated effects of scour in Conowingo Pond during peak flow events on the water quality 

and living resources in Chesapeake Bay. The Stewards of the Lower Susquehanna, Inc.,

also recommend that Exelon remove at least 4 million tons of sediment annually from the 

reservoir to eventually remove all sediment subject to scouring. The Clean Chesapeake 

Coalition requests that Exelon be required to dredge Conowingo Pond and restore oyster 

beds north of the Bay Bridge and SAV in the upper Bay and its tributaries that were 

buried by sediment scoured from Conowingo Pond. The Town of Port Deposit, 

American Rivers, and Henry Immanuel also recommend that Exelon prevent and mitigate 

for the downstream effects of scoured sediments. Maryland DNR notes, however, that it 

is premature to conclude that the Corps’ LSRWA study (described above in Geology and 

Soils) will be adequate to appropriately identify and evaluate sediment and nutrient 

effects on the Bay’s resources related to the Conowingo Project. 

Our Analysis

As we describe in Geology and Soils, sediment and nutrient loading from the 

Susquehanna River Basin is a long-term natural process that has been interrupted by the 

construction of the lower river hydropower reservoirs. Beginning in 1910, with the 

construction of Holtwood dam, followed by the construction of Conowingo and Safe 

Harbor dams in 1928 and 1930, a portion of the Susquehanna River sediment and nutrient 

load has been stored in these reservoirs, and has not reached Chesapeake Bay. So, during 

parts of the past 100 or so years, nutrient loading in the Bay has been lower than it would 

have been without the lower river reservoirs. Some of this sediment and nutrient load, 

however, has been and continues to be re-suspended and scoured from the reservoirs 

during flood events, and deposited in the Bay. The Bay TMDL does recognize that this is 

a watershed-wide issue. 

Some commenters have suggested dredging Conowingo Pond, to allow for 

continued storage of sediment and nutrients, and to avoid the large spikes in loading that 

may occur during scouring flood events. The TMDL recognizes the existing storage 

capacity of the three lower river reservoirs, and that storage capacity may be reduced 

over time as the reservoirs fill in. If that occurs, the TMDL requires that governmental 

jurisdictions in the watershed might need to increase their sediment and nutrientreduction efforts to meet the allocations they have been assigned in the Bay TMDL. A 

primary focus of the TMDL is the preparation of watershed implementation plans that

detail how and when the six Chesapeake Bay states and the District of Columbia will 

meet their pollution allocations in the TMDL. It is reasonable that Exelon and the other 

project owners on the lower river are not considered the primary source of sediment and 

nutrient loading to the Bay, and that the TMDL recognizes that it is a watershed issue. 

We find no justification at this time for requiring Exelon to implement measures such as 

dredging to help control sediment and nutrient loading in the Bay, which would occur in 

the long term whether or not Conowingo dam was in place.
129

Reservoir Fluctuations 

York Haven Project

Reservoir fluctuations have the potential to dewater shoreline habitat, which could 

strand nearshore biota such as young fish, especially if drawdowns occur during the 

spawning and rearing season for shoreline spawning nestbuilders such as smallmouth 

bass, largemouth bass, and sunfish. Fluctuations can also limit the development of SAV 

and emergent vegetation. Nearshore aquatic vegetation is often an important habitat 

element for benthic macroinvertebrates and fish. 

York Haven Power proposes to continue to operate the York Haven Project as it 

has in the past, in a run-of-river mode with a maximum drawdown of 1.1 feet for 

purposes of dam maintenance. No specific recommendations pertaining to reservoir 

fluctuations have been made by any commenting entities, and the Settlement Agreement 

does not include any measures that pertain to reservoir fluctuations. 

Our Analysis

The proposed continued operation of the project in a run-of-river mode would 

result in nearly constant reservoir water surface elevations, when the project has 

sufficient control over river flows. Flow and reservoir level fluctuations would continue 

to occur during high-flow events, or changing natural inflows, but this would be beyond 

the control of the project. Drawdowns of up to 1.1 feet are reserved for specific project 

maintenance activities and are generally scheduled for late summer through fall. This 

timing avoids the spring to mid-summer spawning period of nearly all resident fish, and 

the young of shoreline nest building species would have reached the juvenile life stage 

and be mobile enough to leave shallow shoreline habitat prior to any maintenance 

drawdown. There has been no evidence of fish stranding or any negative effect on 

nearshore spawning habitat attributed to the current drawdown regime.

Muddy Run Project

Muddy Run reservoir can have water surface elevation changes of up to 50 feet on 

a weekly basis during typical operation. Although such fluctuations create poor 

nearshore habitat for aquatic biota, creel surveys in 1972 and 1987 (when the public was

allowed to fish the reservoir) indicate that populations of game fish are present in Muddy 

Run reservoir; large white crappie dominated the catch. This suggests that the forage 

base in the reservoir is adequate. The likely source of both forage and game fish is 

pumping operation from Conowingo Pond. However, Muddy Run reservoir is currently 

off-limits to public recreation and is surrounded by fencing that precludes public access. 

Muddy Run Recreation Lake abuts Muddy Run reservoir. This 100-acre lake provides a 

stable water level habitat that supports an important recreational fishery from the entire 

shoreline and small boats.

Exelon is not proposing any changes in its operation of the Muddy Run Project, 

and no specific recommendations pertaining to reservoir fluctuations have been made by 

any commenting entities.
130

Our Analysis 

Sufficient angling opportunities exist at this project at the Recreation Lake under 

current conditions, and they would continue during the term of a new license. Significant 

fluctuations in the Muddy Run reservoir would continue to affect fish populations, but 

given that the reservoir is not open to the public and is not proposed to be opened under a 

new license, there would be little benefit to restricting current fluctuations. We discuss 

reservoir fluctuations at Conowingo Pond, the lower reservoir of the Muddy Run Project, 

in the following section.

Conowingo Project

Exelon proposes to continue to operate the Conowingo Project as it has in the past. 

This includes maximum reservoir fluctuations between elevations 101.2 and 110.2 feet. 

On weekends between Memorial Day and Labor Day, however, the water level would be 

maintained at or above elevation 107.2 feet to accommodate recreational boating and 

associated activities. No entity has recommended an alternative reservoir fluctuation 

regime. However, The Nature Conservancy and American Rivers suggest run-of-river 

operation of the Conowingo Project. Such operation would result in a relatively constant 

water surface elevation except when inflow to the project exceeds the hydraulic capacity 

of the turbines. 

Our Analysis 

Conowingo Pond fluctuations primarily influence aquatic habitat in the lower 11 

miles of the reservoir (from Hennery Island to Conowingo dam, referred to as the lower 

pond). Upstream of Hennery Island, flow releases from the Holtwood Project have a 

greater influence on water surface elevations than operation of the Conowingo Project. 

Although the current license for the Conowingo Project allows the reservoir to fluctuate 

between elevations 101.2 and 110.2 feet, typical operation results in reservoir fluctuations 

between elevations 105.2 and 109.2 feet. As shown in figure 3-3, the minimum average 

monthly reservoir elevation from January 2004 through September 2010 was at or above 

elevation 104.7 feet for nearly the entire 6+ year period. This is most likely because the 

Muddy Run Project experiences pumping cavitation when Conowingo Pond is below this 

elevation. Exelon estimates that there are a total of 453 acres of habitat within the 9-foot

permitted reservoir fluctuation zone based on an analysis of bathymetry and reservoir 

fluctuations in the lower pond. Of this total, 380 acres (84 percent) are between 

elevations 101.2 and 106.0 feet. The greatest amount of habitat in any 1-foot increment 

in the maximum drawdown zone (98 acres) is between elevations 104 and 105 feet. 

Consequently, under current and proposed future operation, most of the aquatic habitat in 

the drawdown zone would remain submerged.

A key element of nearshore habitat for aquatic biota in lakes and reservoirs is 

cover, where benthic macroinvertebrates and young fish can forage and hide from larger 

predators. In Conowingo Pond, a substantial amount of cover is provided by SAV. 

Exelon estimates that 320.8 acres of SAV occupy the drawdown zone, which is 71 
131

percent of the total aquatic drawdown zone habitat of the lower pond. Most of the SAV 

was found between elevations 104 and 107 feet. The primary growing season for SAV is 

during the warm summer months (June, July, and August). This also is the primary 

spawning and nursery period for important nearshore spawning fish such as black bass 

and sunfish. This corresponds with the period when Exelon is required to maintain the 

water level of Conowingo Pond at or above elevation 107.2 feet on weekends for 

recreational purposes. The net result of this requirement is evident in figure 3-3, where 

the minimum monthly elevation during June, July, and August is above elevation 105.5 

feet and the average monthly elevation is above elevation 108.0 feet. During this period, 

weekly average water surface fluctuations range between elevation 107.5 and 108.8 feet. 

This likely explains why most but not all of the SAV occurs below elevation 107 feet 

under current conditions.

Consequently, continuing to maintain the existing reservoir fluctuation regime 

within an overall range between elevations 101.2 and 110.2 feet and a summer weekend 

minimum elevation of 107.2 feet would be protective of nearshore aquatic habitat and 

associated biota. We note that when inflow to Conowingo Pond exceeds the hydraulic 

capacity of the turbines, Exelon would operate the spill gates to maintain reservoir level 

control, but under spillage conditions the maximum water level in the pond may exceed 

the elevation 110.2-foot high end of the permissible range. We acknowledge that if the 

Conowingo Project would be operated in a run-of-river mode, as The Nature 

Conservancy and American Rivers suggest, the reservoir level would be essentially 

constant at elevation 110.2 feet, which would represent a slight enhancement to nearshore 

habitat compared to existing conditions. An elevation of 110.2 feet would provide an 

additional 55 acres of aquatic habitat, compared to the current normal maximum 

elevation of 109.2 feet. We expect the incremental benefits of run-of-river operation over 

existing conditions to be minimal. 

While a constant reservoir elevation of 110.2 feet would result in a slight 

enhancement to nearshore habitat, it would also allow nuisance invasive plant species 

such as hydrilla to infest areas between the 107-foot contour and the full pond elevation 

of 110.2 feet. This would likely negatively affect shoreline fishing and boating. In 

addition, as discussed in section 3.3.5.2, Recreation and Land Use Resources,

Environmental Effects, it would also negatively affect the ability of larger boats to access 

the reservoir from the tributary boat ramps because at full pond they are not able to pass 

under the railroad bridges at Peters and Conowingo creeks.

Downstream Flow Releases 

In the Settlement Agreement, York Haven Power proposes a continuous minimum 

flow release of 1,000 cfs and an average daily minimum flow release of 2,500 cfs, or 

inflow if less, as measured at the Harrisburg, Pennsylvania, USGS gaging station (York 

Haven Power, 2014a). However, York Haven Power also proposes to install a new 

nature-like fishway at the north end of the main dam, which would serve as the primary 

fish passage facility. The east channel fishway would continue to operate as a secondary 
132

passage facility. York Haven Power proposes to continue the existing flow releases at 

the east channel dam until the nature-like fishway is operational, and then attraction flows 

would be reallocated. Table 3-18 presents a summary of the flow management 

distribution at the project before and after the proposed nature-like fishway construction.

The proposed flow distribution once the nature-like fishway is operational would 

result in a lower minimum flow in the east channel during the upstream passage seasons 

for American shad and resident species, and more flow at the apex of the main dam, to 

enhance passage through the nature-like fishway.

The only comment received by the Commission in opposition to the settlement 

agreement proposed flow releases was from PPL BI in regard to adequate flows for its

cooling water purposes, as discussed above.

Our Analysis

York Haven Power’s flow proposal is similar to its currently licensed flow regime 

that has been provided for more than 30 years. The primary difference is that there 

would be less flow in the east channel, which has had additional flow releases since the 

east channel fishway went into operation in 2000, to attract fish to that facility. With the 

current proposal to shift the primary upstream fish passage route to the nature-like 

fishway, less flow would be provided to the east channel and more flow would be shifted 

to the nature-like fishway and main dam most of the year. The current 4,000-cfs flow 

provided along the main dam during the shad migration season (2 months) would no 

longer be provided, but a 1,000-cfs flow would be provided at the apex of the main dam 

with Three Mile Island. The changes would likely have minimal effects on aquatic 

habitat downstream of the dam, although some areas that were previously wetted would 

receive less flow, while other areas would receive more flow. No concerns were 

expressed by stakeholders regarding the environmental effects of these flow distribution 

changes, which overall should improve upstream fish passage at the project, once the 

nature-like fishway is operational. Because the York Haven Project has a low hydraulic 

capacity and minimal control over river flows, with spillage occurring on average about 

60 percent of the time, these flow distribution changes would only be evident at 

extremely low river flow levels.
133

Table 3-18. Proposed minimum flow schedule for York Haven Project (Source: York Haven Power, 2014a).

Location and Season

Before Nature-like Fishway 

Construction (existing 

conditions)

After Nature-like Fishway 

Construction 

Reason for Change (from 

existing conditions to after 

fishway construction)

Minimum flow below project

(powerhouse + main dam + 

east channel) (all year)

Continuous: 1,000 cfs or 

inflow, whichever is less

Average daily: 2,500 cfs or 

inflow, whichever is less

Continuous: 1,000 cfs or 

inflow, whichever is less

Average daily: 2,500 cfs or 

inflow, whichever is less

No change. These flows may 

be delivered via any 

combination of turbines, spill at 

the main dam, and gate 

releases.

East channel dam

(1) Resident upstream fish 

passage (April 1 through 

beginning of American 

shad passage season (about 

mid-April)

400 cfs 267 cfs

Flow shift to nature-like

fishway as primary resident 

fish passage route; discourage 

migration into east channel

(2) American shad 

upstream passage (about 

mid-April through midJune) 

2,000 cfs 267 cfs

Flow shift to maximize 

attraction flow to nature-like

fishway; discourage migration 

into east channel

(3) Resident fish passage 

(mid-June to end of 

upstream passage season –

December 15)

400 cfs 267 cfs

Flow shift to the nature-like

fishway as primary resident 

fish passage route; discourage 

migration into east channel

(4) Winter (December 15 

through April 1) 0 267 cfs

Enhance east channel winter 

habitat conditions; east channel 

fishway to be left open during 

winter
134

Location and Season

Before Nature-like Fishway 

Construction (existing 

conditions)

After Nature-like Fishway 

Construction 

Reason for Change (from 

existing conditions to after 

fishway construction)

Main channel dam/ nature-like 

fishway 

(1) American shad 

upstream passage season 

(about mid-April through 

mid-June)

4,000 cfs 

1,000 cfs (total) through naturelike fishway channel and 

nature-like fishway

supplemental attraction flow 

channel

Design to provide total 

attraction flow ≥ 5 percent of 

river flow from 5,000 to 

150,000 cfs.

Provide attraction flow to 

nature-like fishway at main 

dam apex; maintain habitat and 

adequate migration flow below 

main dam

(2) Resident fish passage 

(mid-June through midApril)

0

200 cfs minimum flow through 

nature-like fishway channela

Provide attraction flow to 

nature-like fishway at main 

dam apex for resident fish; 

enhance main channel habitat 

conditions; maintain nature-like

fishway as resident fish passage 

route year round

a When river flows are greater than the hydraulic capacity of the generating units plus the required flows in the east 

channel, and at the main dam/ nature-like fishway, flows would be managed to maintain an east channel flow of 267 cfs, 

and maximize the remainder of flows over the main dam and through the nature-like fishway, with the supplemental 

attraction flow channel to be operated with the objective of maintaining a higher attraction flow through the nature-like

fishway (except during the winter period of December 15 to the earlier of April 1 or the start of the American shad 

upstream passage season, when total nature-like fishway flow would be 200 cfs).
135

Conowingo Project 

Exelon proposes to continue to provide the minimum flow releases required under 

the current license, as follows: 

• March 1 – March 31: 3,500 cfs or natural river flow (as measured at the upstream 

USGS Marietta gage No. 0157600), whichever is less;

• April 1 – April 30: 10,000 cfs or natural river flow, whichever is less;

• May 1 – May 31: 7,500 cfs or natural river flow, whichever is less;

• June 1 – September 14: 5,000 cfs or natural river flow, whichever is less;

• September 15 – November 30: 3,500 cfs or natural river flow, whichever is less; 

and 

• December 1 – February 28: 3,500 cfs intermittent release (maximum 6 hours off 

followed by equal amount on).

Several commenters made statements regarding the adverse effects of flow 

releases from the project. Interior, in its section 10(j) recommendation, states that Exelon 

should finalize and implement a flow management plan and implement the flow 

recommendations of The Nature Conservancy or any more restrictive flows required by 

the Maryland certification (when that is issued), returning the river downstream of 

Conowingo to more natural conditions. The Nature Conservancy, in its comments filed 

January 31, 2014, recommended flows be released downstream of Conowingo dam 

sufficient to achieve the following objectives: 

(1) restore persistent habitat and maximum weighted usable area (MWUA)44 for

the spawning, migration, and egg and larval development of diadromous and

resident fish and for macroinvertebrates by providing at least 50 percent of 

historic maximum persistent habitat, minimize the amount of time that less 

than 25 percent of historic maximum persistent habitat is available, and target 

70 percent of MWUA across species and life stages; 

(2) increase the probability of lift entry for American shad, river herring, and

American eel; 

(3) eliminate stranding-related mortality of adult and juvenile fish; 

(4) provide at least 50 percent of available mussel habitat with suitable shear 

stress; 

 

44 Weighted usable area is an index of aquatic habitat that is calculated using the 

Instream Flow Incremental Methodology. It is meant to be used as a comparative 

statistic (for comparing alternative flow levels) and is not an absolute measure of habitat.
136

(5) increase the stability and suitability of basking and hibernation habitats for

map turtles; and 

(6) increase the suitability for SAV and emergent vegetation establishment. 

The Nature Conservancy also recommends that the EIS evaluate two operational 

alternatives: (1) run-of-river operation (passage of the daily average flow measured at 

the USGS Marietta, Pennsylvania, gage plus any intervening flows that enter the river 

between the Marietta gage and Conowingo dam); and (2) the set of operational 

constraints that The Nature Conservancy identified as a potential approach for meeting its 

performance goals, listed above. We refer to this second alternative as the TNC Flow 

Regime. Table 3-19 summarizes the components of the TNC Flow Regime, and includes 

Exelon’s proposed flow regime. The TNC Flow Regime includes restrictions on 

upramping and downramping. In addition, Pennsylvania FBC recommends that Exelon 

should reduce ramping-related stranding of migratory fish by (1) extending the retaining 

wall at the east end of the east fish lift or adding boulder fill in that area to prevent 

generation flow from flooding the spillway pool at high levels of generation, or (2) 

dredging a channel(s) from the spillway pool area to downstream areas to provide egress 

for stranded fishes.

Table 3-19. Summary of Exelon and TNC flow recommendations (Source: Staff).

Month

Minimum flow (cfs)

TNC

Maximum 

flow (cfs)

TNC

Maximum

Downramping 

(cfs/hr)

TNC

Maximum 

Upramping 

(cfs/hr)

Exelon TNC

Minimum

Minimum 

Q>50b

Minimum 

Q<50

January 0/3,500a 11,000

86,000

(January 

and 

February)

20,000

(January 

through June)

40,000

(yearround)

February 0/3,500 12,500

March 3,500 30,000 24,000

April 10,000 35,000 29,000

May 7,500 25,500 17,500

June 5,000 14,000 10,000

July 5,000 8,500 5,500

65,000

(March 

through 

September)

10,000 if 

Q<30,000

20,000 if 

Q<86,000 

(July through 

September)

August 5,000 6,000 4,500

September 

1-14 5,000 5,500 3,500
137

Month

Minimum flow (cfs)

TNC

Maximum 

flow (cfs)

TNC

Maximum

Downramping 

(cfs/hr)

TNC

Maximum 

Upramping 

(cfs/hr)

Exelon TNC

Minimum

Minimum 

Q>50b

Minimum 

Q<50

September 

15-30 3,500 5,500 3,500

October 3,500 6,000 86,000

(October 

through 

December)

20,000

(October 

through 

December)

November 3,500 11,000

December 0/3,500 11,000 a From December 1 through February 28, Exelon proposes an intermittent flow regime, 

with 6 hours of 3,500 cfs followed by 6 hours with no minimum flow.

b If natural inflow is greater than the median flow.

Under Exelon’s proposed flows, minimum flow releases would range from as low 

as 0 cfs for up to 6 hours at a time from December through February, up to 10,000 cfs in 

April. Minimum flows under the TNC Flow Regime would range from 3,500 cfs in 

September when natural flows at the Marietta gage are less than the median flow, up to 

35,000 cfs in April when flows at the Marietta gage are greater than the median flow. 

Under the TNC Flow Regime, the maximum generating flow would also be limited to 

65,000 cfs from March through September, upramping rates would be limited to 40,000 

cfs per hour year-round, and downramping rates would be limited to 20,000 cfs per hour 

overall and 10,000 cfs from July through September if flows are less than 30,000 cfs.

Exelon, in its reply comments filed on March 18, 2014, states that (1) commenting 

entities have no basis for stating that the existing flow regime harms fish and wildlife, 

(2) stranding has not resulted in adverse effects on migratory and resident fishes, (3) a 

robust fishery occurs both upstream and downstream of the project, and (4) the 

recommended TNC Flow Regime would have a major adverse effect on project power 

production and economics. 

Our Analysis

The flow regime downstream of Conowingo dam has the potential to affect a wide 

range of resources, including SAV; the spawning, incubation, and rearing habitat for a 

variety of fish species; and habitat for freshwater mussels, other invertebrates, map 

turtles, and waterfowl nesting. Flow fluctuations associated with project operation also 

has the potential to cause fish mortality due to stranding and to affect upstream fish 

migration. We assess the effects of Exelon’s proposed operation, alternative run-of-river 

operation, and the TNC Flow Regime on SAV, fish habitat, fish migration, fish stranding, 
138

freshwater mussels, and other aquatic invertebrates. Effects on map turtles and waterfowl 

nesting habitat are evaluated in section 3.3.3, Terrestrial Resources.

SAV. As we previously described, SAV downstream of Conowingo dam is limited 

to areas that have finer-grained substrate or are protected from high water velocities 

associated with high river flows. The highest concentrations of SAV are in the lower part 

of the river closer to the mouth of the river, where river levels are influenced by tidal 

flow from the Chesapeake Bay and velocities tend to be lower. Portions of the river 

closest to Conowingo dam have a steeper gradient, a substrate of primarily bedrock and 

boulder, and little SAV. SAV distribution downstream of the dam is more influenced by 

existing substrate conditions and natural high-flow events, which have the potential to 

scour and redistribute finer-grained substrate, than by normal day-to-day project 

operation. 

Fish Habitat. To assess the effects of proposed operation and alternative flow 

regimes on habitat for fish and invertebrates, Exelon conducted study 3.16, Instream 

Flow Habitat below Conowingo Dam (Gomez and Sullivan and Normandeau, 2012a). 

The study included evaluation of effects on different life stages of American shad, striped 

bass, shortnose sturgeon, smallmouth bass, several taxa of aquatic insects (mayflies, 

stoneflies, caddisflies), and freshwater mussels. The study used the River2D model to 

simulate hydraulic conditions in a study reach extending from Conowingo dam to the 

downstream end of Spencer Island (where tidal effects begin). The calibrated hydraulic 

model was used to simulate habitat conditions over a range of flows. In addition, a 

habitat persistence analysis was performed to assess the effects of peaking operation by 

determining the area of habitat that maintained a habitat rating of “good” (composite 

habitat suitability index of 0.5) or higher over the flow range that represents a given 

peaking cycle. The Nature Conservancy used the results of this persistence analysis to 

develop the TNC Flow Regime. 

Implementing run-of-river operation downstream of Conowingo dam would 

benefit mobile life stages of fish (fry, juveniles and adults) by reducing the frequency and 

magnitude of flow changes compared to current and proposed operation, which would 

improve habitat stability. This would help fish to seek out and remain in areas with 

suitable depth, velocity, and substrate conditions, without incurring the energetic costs 

associated with shifting locations to seek favorable habitat when flow conditions change. 

Implementing the TNC Flow Regime flows would reduce the magnitude and rate of flow 

changes compared to existing and proposed operation, which would provide an 

intermediate level of reduction in energetic costs. Reducing the magnitude and extent of 

flow fluctuations would provide even greater benefits to non-mobile life stages of fish 

(eggs) and less mobile organisms including fish larvae and aquatic invertebrates. Any 

increase in the production of aquatic insects would increase the amount of forage 

available and the potential production of juvenile fish.

Assessing the extent of the benefit that would be provided to any individual life

stage and species of fish or invertebrate from reducing the magnitude of flow fluctuations 
139

is a complex challenge. Evaluating the effects on any individual life stage requires 

substantial assumptions to be made regarding the effects of changes in amount, quality, 

and location of the available habitat for that life stage, as well as the influence of the rate 

at which those attributes change. Any benefits that may occur to a particular species and 

life stage from a specific flow level, however, may not necessarily transfer to another 

species and life stage. These uncertainties are magnified during the assessment of 

potential population effects for a species, which requires incorporating effects on each 

life stage.

Focusing the instream flow evaluation on the spring migration and spawning 

period for American shad, river herring, and hickory shad may have the most merit. 

Enhancing flows during the spring period has the potential to provide increases in the 

production of these anadromous species without unnecessarily constraining project 

operation in other seasons, including the summer and winter seasons when there are 

peaks in the demand for power for cooling and heating. Substantial use of the river 

downstream of Conowingo dam for spawning by each of these species has been 

documented (Normandeau and Gomez and Sullivan, 2012b), and juveniles of these 

species (as well as gizzard shad) likely provide a seasonal source of forage for migratory 

striped bass. We provide a further analysis of effects on anadromous and resident species 

below under “Alternative Flow Regime.”

Fish Migration. Although Exelon’s studies have found little evidence of a 

relationship between operational flow releases and the ability of upstream migrating fish 

to find and enter the east and west fish lifts, it is possible that reducing the frequency and 

magnitude of flow fluctuations could improve fish passage efficiency. The results of 

radio telemetry studies conducted in 2010 and 2012 (Normandeau and Gomez and 

Sullivan, 2011; 2012c) indicate that many American shad that migrate upstream to the 

tailrace area subsequently returned downriver within a few hours or days. While this 

type of movement has been observed on other rivers unaffected by fluctuating flow 

releases, if the magnitude of operational flow changes was reduced during the migration 

season, it is possible that some of these fish would remain in the tailrace area for a longer 

period of time and increase their success in finding and entering one of the fish lifts. 

Additional discussion of effects on fish migration is included below under our discussion 

of upstream fish passage.

Fish Stranding. Reducing the magnitude and frequency of flow fluctuations could 

benefit fisheries resources by reducing the number of fish that are injured or killed when 

they are stranded as flow and water levels downstream of Conowingo dam are reduced. 

However, stranding studies conducted by Exelon (Normandeau and Gomez and Sullivan, 

2012d) indicated that few fish are killed by stranding under existing operation, and about 

90 percent of those killed were gizzard shad, carp, and catfish species (table 3-20). 

Although implementing run-of-river or TNC Flow Regime flows could reduce this source 

of mortality, the results of Exelon’s stranding surveys indicate that the magnitude of this 

benefit would be minor. There would also be minimal benefit in implementing the 

Pennsylvania FBC recommendation to extend the retaining wall at the east end of the east 
140

fish lift, add boulder fill in that area to prevent generation flow from flooding the 

spillway pool at high levels of generation, or dredge a channel(s) from the spillway pool 

area to downstream areas to provide egress for stranded fishes. 

Table 3-20. Total number of dead fish and crabs observed during 12 stranding 

surveys (4 in each season) conducted within and just downstream of the 

spillway reach below Conowingo dam (Source: Normandeau and 

Gomez and Sullivan, 2012d).

Spring Summer Fall Total %

American eel 1 1 0.1

River herring 1 1 0.1

American shad 46 46 4.4

Gizzard shad 675 40 41 756 72.5

Carp 80 4 3 87 8.3

Minnows 1 1 0.1

Quillback 2 2 0.2

Shorthead redhorse 1 1 2 0.2

Catfishes 75 7 12 94 9.0

White perch 1 1 0.1

Striped bass 1 1 0.1

Banded killifish 6 6 0.6

Smallmouth bass 2 1 3 0.3

Largemouth bass 9 1 10 1.0

Sunfish 4 4 0.4

Walleye 1 4 5 0.5

Darters 3 3 0.3

Unidentified 19 19 1.8

Blue crabs 1 1 0.1

Freshwater Mussels. As part of study 3.16, Instream Flow Habitat Below 

Conowingo Dam (Gomez and Sullivan and Normandeau, 2012a), Exelon examined the 

effects of operational flows on mussel habitat by calculating and mapping shear stress at 

the river bed in the study area over a range of flows. The study found that mussel CPUE

versus shear stress plots showed that model-predicted shear stress related fairly well to 
141

observed mussel densities. However, the distribution of mussels below Conowingo dam 

is likely limited by the shear stress that occurs during spring runoff, and locations that are 

sufficiently protected from high shear stress during spring runoff would also be 

sufficiently protected from shear stress during peaking operation. Accordingly, we 

conclude that reducing flow fluctuations by implementing run-of-river or the TNC Flow 

Regime operations would provide a limited benefit to mussels.

Alternative Flow Regime. Our analysis of Exelon’s instream flow study indicates 

that several combinations of minimum and maximum flows may improve habitat for 

some species and life stages, but those flow combinations are not consistent among the 

evaluation species. Certain flows may improve habitat for some species and life stages, 

while those same flows would reduce habitat for other species and life stages. Selection 

of an alternative flow regime would require balancing among the several target species 

and life stages (determine which life stage is most important for each time interval), as 

well as consideration of the effects of an alternative regime on project power production 

and economics. As we note above, Exelon’s instream flow study included a habitat 

persistence analysis, and the report summarized that analysis by month, using only the 

species and life stage that may be present during that month and for which there is a 

relatively high amount of structural habitat available (relative to total wetted area). 

Table 3-21 summarizes the results of that analysis, showing the range of flows that would 

provide the TNC target of 70 percent of MWUA by month, and also showing the normal 

range of flows in Exelon’s existing and proposed operation, and the median unregulated 

flow. This table, however, only shows evaluation fish species, because use of 

invertebrates and the “guilds” life stages would consistently show a low end of the flow 

range less than current minimum flows.45 In addition, we adjust the life stages by month 

to those key life stages present, to reflect the changing importance of certain species and 

life stages during certain months (such as when anadromous species are present).

Table 3-21 indicates that, overall, the current and proposed Exelon operation 

generally bracket the range of flows that would provide 70 percent of MWUA as 

determined by the instream flow study. From December through March, when Exelon 

reduces to zero minimum flow for 6-hour intervals, however, the MWUA criterion would 

not be met for those 6-hour intervals. Eliminating the zero minimum flow periods during 

those months would likely provide some benefits to aquatic habitat, and Exelon should 

have no trouble in meeting a continuous flow requirement (of 3,500 cfs), because median 

flows are higher during those months. For the remainder of the year, Exelon’s minimum 

flows are lower than the low end of the 70 percent MWUA criterion in April, May, and 

 

45 Gomez and Sullivan and Normandeau (2012a) state that some flow ranges were 

limited by the lowest or highest production run flow, thus the true flow range providing 

this habitat may fall outside of the modeled flows. However, even some fish life stages 

selected for our analysis showed this low end of the flow range. 
142

June, but higher than the criterion the remainder of the year. In April, Exelon provides a 

minimum flow of 10,000 cfs (compared to the 70 percent minimum criterion of 13,008 

cfs), but because April is the highest flow month of the year, Exelon overall maintains 

higher average releases during April, and there would be no need to adjust minimum 

flows.46 In May, Exelon’s minimum flow is very close to the 70 percent minimum 

criterion. In June, at the end of the spawning period for shad and striped bass, Exelon 

currently reduces its minimum flow from 7,500 to 5,000 cfs. If that reduction occurs on 

June 1 (as it does currently), that could adversely affect spawning and early-fry 

development for later spawning shad by reducing the area of suitable spawning and 

incubation habitat during the period of the day when only the minimum flow is provided. 

Areas that would be available for spawning and incubation during higher generation 

periods of the day may not be available or may be dewatered at a minimum flow of 5,000 

cfs, and extending a 7,500-cfs minimum flow until mid-June would provide additional 

protection to spawning and incubation habitat. There would be no need to extend this 

minimum flow into late June, after spawning and early-fry development has ended. 

Maximum flows have also been a concern at Conowingo, and The Nature Conservancy

recommended that maximum flows be capped at 65,000 cfs from March through 

September. The habitat persistence analysis, however, does not support such a 

restriction, as some of the key life stages in all months still maintain the 70 percent 

minimum criterion at the full station discharge of 86,000 cfs. While 86,000 cfs is the 

high end of the flow range that was limited by the production run flow, according to 

Gomez and Sullivan and Normandeau (2012a), that analysis still indicates that there is 

little basis for a 65,000-cfs maximum flow cap.

We understand that this is a somewhat “broad-brush” analysis of instream flows 

downstream of Conowingo, and that certain species and life stages may have narrower or 

higher flow bands where MWUA is provided. As we discuss earlier, the flow issue is 

complex downstream of Conowingo, but Exelon’s studies have provided substantial 

information on the effects of flow releases from Conowingo. Based on this information, 

Exelon’s current flow regime is generally adequate for protection of aquatic resources 

downstream of the project, although some adjustments to these flows as we discussed 

(eliminating periods of zero minimum flow in December through February, and 

increasing the minimum flow to 7,500 cfs in the first half of June) could provide 

additional protection to downstream aquatic habitat. 

The Nature Conservancy recommends that run-of-river operation be considered at 

Conowingo. We previously briefly discussed potential benefits of such operation, but 

strict run-of-river operation does not appear to be technically feasible at Conowingo. If 

 

46 The 90 percent exceedance flow in April at the Conowingo USGS gage is

29,690 cfs (see table 3-6). 
143

any run-of-river operation is tied to inflow at the Marietta gage (plus inflow downstream 

of Marietta), Exelon may not be able to duplicate Marietta flows, because of the 

operation of the upstream Safe Harbor and Holtwood projects. Safe Harbor, with a total 

hydraulic capacity of 110,000 cfs, generally controls river flows at flows less than its 

hydraulic capacity. Safe Harbor is a peaking station with no minimum flow releases, so 

downstream flows may fluctuate from zero up to full capacity on a daily basis. The 

Holtwood Project is immediately downstream of Safe Harbor and also controls the river 

up to its current newly expanded capacity of about 61,000 cfs. If Conowingo was to 

attempt to operate so that it passes on a continuous basis the daily average flow at the 

Marietta gage, plus inflow downstream of Marietta, as recommended by The Nature 

Conservancy, it would likely be an operational challenge. Exelon’s operation would 

likely be in a constant state of flux because actual inflow to Conowingo Pond would be 

fluctuating over a wide range (as a result of upstream operation at Safe Harbor and 

Holtwood), potentially causing major fluctuations in Conowingo Pond as Exelon 

attempted to match Conowingo releases to the Marietta flows (plus other inflow). In 

addition, not all of the tributaries between Marietta and Conowingo are gaged, so Exelon 

would not have reliable inflow data for all of the tributaries. 
144

Table 3-21. Summary of Exelon’s habitat persistence analysis by month, showing the range of flows (cfs) providing 

70 percent of the MWUA for fish species and life stages likely to occur during each month, compared to 

Exelon’s current operation and median unregulated flow (Source: Gomez and Sullivan and Normandeau, 

2012a; Staff).

Parameter Jan.a Feb.a Marcha Aprilb Mayc Juned Julye Aug.f Sept.f Oct.f Nov.f Dec.g

70% of 

MWUA

3,127 –

86,000

3,127 –

86,000

3,127 –

86,000

13,008 –

86,000

7,744 –

86,000

7,744 –

86,000

2,000 –

86,000

2,000 –

86,000

2,000 –

86,000

2,000 –

86,000

2,000 –

86,000

2,000 –

86,000

Exelon 

operation

0/3,500 –

86,000

0/3,500 

– 86,000

3,500 –

86,000

10,000 –

86,000

7,500 –

86,000

5,000 –

86,000

5,000 –

86,000

5,000 –

86,000

5,000/

3,500 –

86,000

3,500 –

86,000

3,500 –

86,000

0/3,500

–

86,000

Median 

unregulated 

flow

27,732 32,617 61,744 63,752 38,768 20,661 13,045 9,201 7,995 9,845 22,927 30,672

a Includes only adult smallmouth bass and adult striped bass.

b Includes adults and spawning for American shad, shortnose sturgeon, and striped bass.

c Includes adults, spawning, and fry for American shad, shortnose sturgeon, and striped bass.

d Includes adults, spawning, fry, and juveniles for American shad and striped bass.

e Includes adults, fry, and juveniles for striped bass and fry and juveniles for American shad.

f Includes adult and juvenile striped bass and smallmouth bass and juvenile American shad.

g Includes adult and juvenile striped bass and smallmouth bass.
145

Upstream Fish Passage

As we described in section 3.3.2.1, Water Resources, Affected Environment, 

volitional upstream fish passage for anadromous species has been provided at the four 

lower-river hydroelectric projects since the year 2000. An experimental fish trap (with 

trucking) was first installed in 1972 at Conowingo dam, but passage was not provided at 

all four dams until completion of the east channel fishway at York Haven in 2000. While 

fish passage facilities have been in place for many years, inefficiencies in their operation 

have been documented at some of the projects. Only the Safe Harbor Project has 

demonstrated consistently high efficiency. Inefficiencies in upstream passage were a 

stakeholder concern at both York Haven and Conowingo, and those issues are discussed 

separately by project. American eel passage to date has been limited to experimental 

operations and trapping and trucking from Conowingo, but is also an issue for all the 

projects on the Susquehanna River. The American eel issue is discussed 

separately below. 

York Haven Project

York Haven Power is proposing, consistent with the Settlement Agreement, to 

improve upstream fish passage at the project by constructing a nature-like fishway where 

the upstream end of the main dam joins Three Mile Island (referred to as the “apex”). 

Pennsylvania DEP did not sign the agreement but has indicated it would issue 

certification that is consistent with the agreement. 

Our Analysis

American shad passage counts on the river (table 3-13) show that shad passage at 

the east channel fishway has been relatively low, generally only from about 2 to 

22 percent of the count at the downstream Safe Harbor dam, and not exceeding 

10 percent since 2003. This may not have been entirely as a result of inefficiency at the 

east channel fishway.

47 Radio telemetry studies conducted by York Haven Power in 

2010 found that many shad that did reach the project area did not reach the east channel

fishway. Of 174 radio-tagged shad exiting the downstream Safe Harbor fish lift, 

70 percent reached the York Haven Project area. Of those, 100 percent passed through 

the York Haven tailrace and 78 percent were detected in the apex area of the main dam, 

where tagged fish spent the most time of any of the locations at York Haven. Only 

 

47 There is spawning habitat in the 22 river miles between the Safe Harbor Project 

and York Haven and in years when spring water temperatures increase rapidly in the 

river, shad may cease migration once spawning temperatures are reached and use 

spawning habitat downstream of York Haven. While some shad may spawn downstream 

of York Haven in any year that portion of the run may be greater if water temperatures 

increase rapidly. 
146

4 percent (5 tagged shad) successfully passed above York Haven dam through the east 

channel fishway, and another 2 fish passed through the fishway but immediately dropped 

back downstream through the attraction flow gates (York Haven Power, 2011; 2013). 

These data indicate that the apex area of the main dam would be a good location for a 

fishway, likely a better location than the existing east channel fishway.

Fish passage options at this site, which has a maximum head of only 7 feet, would 

be a pool and weir or vertical slot fishway, similar to the east channel fishway, or a 

nature-like fishway. A fish lift would not be a good option at this site because of the low 

head and the somewhat remote location, making operation and maintenance more 

difficult. As the record shows, consultations with the fisheries agencies resulted in the 

selection of the nature-like fishway as the preferred alternative, ultimately resulting in the 

inclusion of this design in the Settlement Agreement. The proposed fishway would 

consist of an approximately 300-foot-wide and 500-foot-long channel with arched weirs 

made from natural stone and boulders to be harvested from the river immediately 

downstream of the main dam. The fishway base material would consist of a large stone 

mix with a median diameter (D50) of 18 inches, and large rock/boulders that form the 

fishway weirs would be 3- to 5-foot-diameter rock set into the 18-inch D50 base material. 

The large rocks would be arranged to form an arched weir, with the large rocks 

approximately 1-foot apart. Flows through the fishway would pass between and over the 

large rocks with the water level dropping approximately 0.7-foot from the upstream to 

downstream side of each rock weir. There would be a 65-foot-wide ‘thalweg’ located 

within the fishway, which would have a channel invert approximately 1-foot lower in 

elevation than the adjacent fishway channel. This would provide a deeper channel to 

concentrate flows during periods of low headpond elevations and river flows outside of 

the adult American shad migration season. The gradient through the fishway would be 

approximately 1.5 percent. Figure 3-14 shows the location of the proposed nature-like 

fishway, the east channel dam, the rock harvesting area, and staging areas.
147

Figure 3-14. Proposed location of the York Haven nature-like fishway and associated 

construction sites (Source: York Haven Power filing of updated figure for 

Nature-like Fishway Conceptual Design Final Report, filed June 10, 2013).

The fishway would have a normal minimum flow through the fishway of 200 cfs 

and would include a supplemental attraction water supply of 800 cfs, to be provided via a 

parallel concrete channel. This would result in a total minimum flow of 1,000 cfs from 

the apex area of the dam, to attract shad to the fishway location. At the same time, the 
148

minimum flow from the east channel would be reduced to 267 cfs year-round (from the 

current minimum of 2,000 cfs during the shad passage season). This would reduce 

attraction of shad to the east channel and increase attraction toward the nature-like 

fishway, which would become the primary route for upstream passage at the project. The 

east channel fishway would continue to operate year-round for resident fish passage, but 

it would become a secondary route for shad and other anadromous species. The naturelike fishway would also be designed so that a full range of anadromous, catadromous, and 

resident species could use the facility for upstream passage, and downstream passage if 

fish can locate the facility on their downstream migration. Downstream passage is 

discussed below in greater detail.

With this arrangement for fish passage, some shad would likely continue to be 

attracted to the powerhouse tailrace, because under lower flow conditions the majority of 

flow from the project would be released from the powerhouse (up to full powerhouse 

capacity). However, the applicant’s radio telemetry studies found that 78 percent of the 

fish that were detected in the tailrace ended up in the apex area, where the nature-like 

fishway would be located, and those fish lingered in that area for the longest time of any 

of the locations monitored. The proposed location and design of the nature-like fishway 

would constitute an enhancement of existing upstream fish passage facilities at the 

project, and should improve fish passage effectiveness at the project. Another future 

monitoring technology provided for in the Settlement Agreement is the use of PIT tag 

monitoring devices. While the methodology for using these devices in a 300-foot-wide 

nature-like fishway has not yet been developed, the upstream end of the nature-like 

fishway would be designed to accommodate future installation of PIT tag monitoring 

devices at such time that these tag monitoring devices become available and feasible for 

reliably monitoring American shad exiting the fishway. 

Under the Settlement Agreement, York Haven Power proposes to conduct an 

effectiveness study beginning in year 2 of fishway operation, continuing for 2 years, 

using radio-tagged shad. The Settlement Agreement establishes an “Upstream Shad 

Passage Target” that at least 75 percent of the shad counted at the downstream Safe 

Harbor Project be passed above York Haven dam (using all passage routes), and a 

“Project Area Passage Success Criteria” that 85 percent of the shad that reach the York 

Haven Project successfully pass upstream of the project (using all passage routes). If the 

passage target or success criteria are met after 2 successive years of study, then the 

project would be considered as successfully meeting its target and no additional passage 

studies would be needed. If the target effectiveness is not met, after consideration of 

extenuating circumstances such as unusual river flows or high water temperatures, 2 

additional years of study would be conducted after a hydraulic evaluation of the fishway 

and possible modifications to the design or operation (attraction flows) of the fishway. 

Radio telemetry studies can be an effective methodology for monitoring fish 

movements as they approach a fishway and for determining the percentage of fish that are 

able to pass it. The proposed studies are appropriate for a major new fish passage 

facility, particularly because a nature-like fishway design has never been constructed for 
149

American shad at a hydroelectric project on a major North American river.48 The 

establishment of passage targets and success criteria, used properly, allow a 

determination of whether the fishway is operating as designed. Caution is needed, 

however, because many factors beyond engineering design and hydraulics may affect 

effectiveness, particularly for shad. 

The Safe Harbor Project is considered to have the most effective upstream fish 

passage facilities on the Susquehanna River, and perhaps one of the most effective on the 

Atlantic coast. Safe Harbor consistently lifts on-average about 71 percent of the shad 

counted at the downstream Holtwood Project, but that has ranged from 45 to 98 percent 

since 1997, with 13 of 17 years not reaching the target effectiveness of 75 percent 

(table 3-22). While Safe Harbor has not met the 75 percent criteria proposed for York 

Haven in all years, Safe Harbor is still considered highly effective. The distance between 

Holtwood and Safe Harbor is only 7 miles of reservoir habitat, while the distance 

between Safe Harbor and York Haven is about 22 miles, including both large reservoir 

(about 10 miles) and riverine habitat (about 12 miles) that contains suitable spawning 

habitat. It may be unrealistic to expect that the same effectiveness can be achieved at 

York Haven, especially because fish reaching York Haven would be doing so at the end 

of the migration period when water temperatures may be warming quickly, and reaching 

the range when fish would begin spawning.49 

The Settlement Agreement acknowledges this issue, and while the upstream shad 

passage target is at least 75 percent of the shad counted at the downstream Safe Harbor 

Project to be passed above York Haven dam, compliance is based on the project area 

passage success criteria that 85 percent of the shad that successfully reach the York 

Haven Project area successfully pass upstream of the project. This properly recognizes 

that York Haven Power has no control over whether or not shad reach the project area. 

 

48 A nature-like fishway was recently installed on a lock and dam on the Cape Fear 

River in North Carolina, but effectiveness data are not yet available for that facility.

49 In fact, York Haven Power’s 2010 radio telemetry study found that only 70 

percent of the tagged fish released at Safe Harbor reached the York Haven Project area, 

indicating that some fish did use the habitat between the projects, or had no motivation to 

continue upstream migration to York Haven. 
150

Table 3-22. Numbers of shad lifted at Holtwood and Safe Harbor dams, and the 

effectiveness of the Safe Harbor fish lift, reported as percent of the 

Holtwood passage (Source: Staff).

Year Holtwood Safe Harbor % of Holtwood

1997 28,063 20,828 74

1998 8,235 6,054 74

1999 34,702 34,150 98

2000 29,421 21,079 72

2001 109,976 89,816 82

2002 17,522 11,705 67

2003 25,254 16,646 66

2004 3,428 2,109 62

2005 34,156 25,425 74

2006 35,968 24,929 69

2007 10,338 7,215 70

2008 2,795 1,252 45

2009 10,896 7,994 73

2010 16,472 12,706 77

2011 21 8 --a

2012 4,238 3,089 73

2013 2,503 1,927 77

2014 2,528 1,336 53

Average 71 a The Conowingo and Holtwood fish lifts were not operated the entire migration season 

because of construction at Holtwood, so 2011 was not a representative year.

Muddy Run Project

The Muddy Run Project is a pumped storage project with an offstream upper 

reservoir that does not physically block upstream fish migration, but instead may affect 

migration by creating flow patterns that may confuse migrating fish or create areas with 

high velocities that may delay migration. There is no proposal or need for passing fish 

into the Muddy Run upper reservoir, and in fact the objective is to keep migrating fish 

out of the reservoir. Some migrating fish would be entrained and pumped into the upper 

reservoir, resulting in a loss of those fish to the overall population, unless those fish are 

able to survive passage back to the Susquehanna River/Conowingo Pond during the 
151

generation cycle. Both Interior and NMFS reserve their authority to prescribe fishways 

during the term of the license, and both agencies recommend that the project be operated 

to allow safe, timely, and effective fish passage past the project. Interior, as part of its

preliminary fishway prescription, requires preparation of FPOP to describe Muddy Run 

Project operation during the fish passage season including regular maintenance activities 

and emergency procedures. Interior also requires an FPMP, including an American shad 

passage monitoring plan, for post-FPOP implementation monitoring, with the criteria for 

success to be consistent with the goals and objectives set forth in the Susquehanna River 

Anadromous Fish Restoration Plan (85 percent passage effectiveness, with target passage 

of 80 percent within 36 hours). However, in a letter filed with the Commission on 

February 28, 2014, Interior amended its preliminary fishway prescription, and dropped 

the requirement for specific target effectiveness at Muddy Run (80 percent within 36 

hours), but instead would require that Muddy Run demonstrate safe, timely, and effective 

fish passage past the project, based on site-specific studies or other available information. 

Interior states that while it believes that Muddy Run operation may affect fish migration, 

the effects may not be sufficient to affect the fisheries agencies goals for this reach of the 

river. As part of the FPMP, Exelon would be required to conduct an effectiveness 

monitoring study every 10 years beginning in 2018, and if effectiveness is not met, 

Exelon would be required to implement operational or structural measures to improve 

effectiveness.50 NMFS is concerned that flow patterns in the vicinity of the project may 

delay American shad migration, and recommends that FWS’ reanalysis of a 2008 shad 

radio telemetry study be considered in the analysis of this issue. Passage measures 

related to American eel are discussed below in a separate section. 

In its reply comments filed on March 18, 2014, Exelon states that it is opposed to 

Interior’s preliminary fishway prescription, but is in agreement with the conditions of the 

draft certification. Pennsylvania DEP issued a final certification on June 3, 2014. While 

Exelon has not indicated the final certification represents its proposal, our review of the 

draft and final certifications found that they are nearly identical. Thus, Exelon is in 

agreement with the fish passage conditions of the certification that require at least 88 

percent successful passage of upstream-migrating adult shad past the Muddy Run 

 

50 By its filing of March 28, 2014, Interior notified the Commission that it had 

reached an agreement in principle with Exelon on a modified fishway prescription, but 

that agreement has yet to be reduced to writing and signed. Because we are unsure of the 

details of that agreement, our analysis focuses on the preliminary fishway prescription, as

amended by Interior’s February 28, 2014, filing.
152

Project,51 80 percent survival of downstream-migrating adult shad, and 95 percent 

survival of downstream-migrating juvenile shad. In addition, Exelon agrees to conduct 

additional effectiveness studies at Muddy Run if the upstream Holtwood Project fails to 

meet its target effectiveness and Pennsylvania DEP determines that Muddy Run 

operation is a proximate cause for Holtwood failing to meet its target. Radio telemetry 

studies would be conducted over a 4-year period, and if the studies demonstrate that less 

than 88 percent of the tagged shad are successful in passing upstream of the Muddy Run 

Project area, Exelon would amend its FPOP to provide measures to enhance upstream 

passage past Muddy Run. Exelon would also submit a plan to continue to provide for the 

target downstream passage survival rates (80 percent for adult shad and 95 percent for 

juvenile shad) by January 15, 2015. By February 15, 2026, Exelon would prepare a plan 

for Pennsylvania DEP approval to measure the passage of American shad moving 

downstream through the project area. If the studies determine that the project is not 

achieving the minimum passage rates, then Exelon would be required to develop a 

mitigation plan. 

Our Analysis

Exelon conducted multiple studies on the effects of Muddy Run operation on 

migratory fishes, summarized in Normandeau and Gomez and Sullivan (2012k). These 

studies included three radio telemetry studies involving more than 500 radio-tagged adult 

shad, data from other lower Susquehanna River studies pertaining to shad run timing, 

hydraulic modeling from the expansion of the upstream Holtwood Project, and near-field 

velocity profiles at Muddy Run. Other available reports included FWS re-analysis of 

Exelon telemetry data and juvenile shad entrainment at Muddy Run (Sweka, 2013; 

Pugh, 2013). The Exelon studies concluded that the effects of the Muddy Run Project on 

upstream and downstream shad passage are negligible. Radio telemetry studies found 

that a majority of shad in upper Conowingo Pond migrate upstream along the east bank 

of the river and would pass in close proximity to the Muddy Run tailrace. This would be 

expected because higher flows occur on the east side of the river associated with flows

discharging from the upstream Holtwood tailrace and Muddy Run releases. Those 

studies found that successful upstream passage of tagged (and detected) shad past the 

Muddy Run Project was 91 percent in 1989, 80 percent in 2001, and 84.5 percent in 2008

(average of 85.2 percent). Telemetry studies in 2001 and 2008 provided data on the adult 

shad entrainment rate during Muddy Run pumping operation from April to June, and 

those rates ranged from 3.6 to 5.1 percent. Exelon’s review of Holtwood Project 

modeling found that river velocities may approach 7.5 to 10.0 fps when both post-

 

51 This differs slightly from Interior’s previously recommended 85 percent passage 

effectiveness, with target passage of 80 percent within 36 hours. However, Interior

commented that the Pennsylvania DEP certification conditions for fish passage (when 

issued) should be considered an alternative for consideration.
153

expansion Holtwood and Muddy Run are generating at or near full capacity (total flow of 

about 94,000 cfs). This indicates that parts of the river channel would be reaching 

velocities that may deter shad, potentially causing some migratory delays, but Exelon 

states that large portions of the river channel would remain with suitable velocities for 

upstream migration, based on field measurements of velocities in the immediate project 

vicinity. For downstream juvenile shad passage, Exelon estimated that for fish that were 

in the zone of influence during pumping, 22.6 percent of those fish could be entrained. 

For the overall population, however, Exelon estimated that only 2.9 to 6.6 percent of the 

population would be vulnerable to entrainment during peak outmigration times, because 

the project is not pumping during many of the peak hours of outmigration (Normandeau 

and Gomez and Sullivan, 2012g). These data indicate that the project already meets the 

agencies’ effectiveness targets for upstream adult shad passage and downstream juvenile 

shad passage.

The reviews by Sweka (2013) and Pugh (2013), however, do not agree with the 

Exelon study results and argue that Exelon has understated the effects of the project on 

upstream migration and entrainment of juvenile shad. Sweka (2013) states that the 

Exelon data show that project releases do result in a slower travel time for adult shad 

migrating upstream in those flows. He also states that only 18 percent of upstream forays 

by migrating shad were successful at continued passage past the Muddy Run tailrace

from the downstream Sicily Island to the upstream Deepwater Island with no fall back 

behavior, and some individual fish needed to make several forays prior to successfully 

passing Muddy Run. Sweka concludes that project operation results in migratory delays 

and possible termination of upstream migration by shad. Pugh (2013) states that by 

adjusting the periods when juvenile shad may actually be passing the project, based on 

information from the scientific literature, the actual entrainment rate for juvenile shad 

would be from 12.3 to 14.5 percent of the population, and not 2.9 to 6.6 percent as 

estimated by Exelon. 

Exelon, in its reply comments filed on March 18, 2014, states that the Sweka 

(2013) and Pugh (2013) reviews of the data were flawed and that they overstate the actual 

effects of the project.

Our assessment of these conflicting studies and analyses is that the argued 

differences in migration and entrainment rates may be within the range of error for the 

field studies and the data analysis. While the field studies may do a reasonable job of 

representing the “real world,” there are issues with any field study (tag losses, differences 

in behavior of tagged fish, equipment failures, etc.) that may influence the study results. 

Instead of trying to determine whose studies or analyses are most correct, our conclusion 

is that the studies and analyses have overall shown that the Muddy Run Project does not 

have an adverse effect on a major proportion of the shad population migrating past the 

project, and has not resulted in major delays to the shad migration. In addition, with 

Exelon now agreeing to the conditions of the certification, Exelon has committed to 

maintaining the effectiveness targets required by Pennsylvania DEP, would monitor this 
154

effectiveness via the studies required by the certification as part of its FPOP, and would 

mitigate any effects of the project if the target effectiveness is not maintained. 

Both the fishway prescription and the certification would require additional 

effectiveness studies, but on different time schedules. The fishway prescription would 

require periodic studies (every 10 years) beginning in 2018, while the certification would 

require upstream passage effectiveness studies only if Pennsylvania DEP determines that 

Muddy Run operation is causing the upstream Holtwood Project to not meet its

effectiveness targets. Downstream passage effectiveness studies would be required 

beginning in 2026, for the certification. Both the fishway prescription and the 

certification would require that additional measures be implemented if effectiveness 

targets are not met. It appears that the fishway prescription and the certification would 

accomplish the same goals, but on a slightly different timetable.

Conowingo Project

The Conowingo Project currently operates two fish passage facilities: the east fish 

lift for volitional upstream passage into Conowingo Pond, and the west fish lift, for 

collection of shad for egg-taking and other experimental purposes. Exelon proposes to 

continue operating these facilities and to implement a preventive maintenance program at 

the east fish lift, to extend the life of the facility through the new license term. Several 

commenting entities have stated that the current facilities are inadequate and outdated and 

fail to meet the required effectiveness to achieve successful anadromous fish restoration 

in the Susquehanna River. Both Interior and NMFS reserve their authority to prescribe 

additional fishways during the term of the license, and Interior also provides a 

preliminary fishway prescription for the project for both anadromous and catadromous 

species.52 Interior also recommends that Conowingo fish passage facilities need an 

operation and maintenance plan and a fish passage effectiveness monitoring plan 

(FEMP), and as a section 10(j) measure recommends that alternative G of the fishway 

prescription be implemented. Alternative G would include:

• Phase I: Construct a new west fish lift for both trap and trucking and direct 

volitional upstream shad passage (two 6,500-gallon hoppers), with an auxiliary 

water system of 2,600 cfs. The objective would be to truck 50,000 adult shad per 

year. Create a 5,000-foot zone of passage53 on the east and west shores of the 

tailrace below the dam. Implement a maximum downramping rate of 20,000 

cfs/hour. Make channel modifications downstream to eliminate stranding in the 

spillway channel.

 

52 Fish passage for American eel is discussed below in a separate section.

53 A zone of passage is a reach within a stream where depth and velocities are 

maintained within suitable ranges for upstream or downstream fish passage.
155

• Phase II: Modify the east fish lift stilling basin to allow a 900-cfs attraction flow, 

as originally designed. Relocate east fish lift entrance A to upstream of the 

Kaplan unit boils. Construct a new entrance D and collection gallery to east fish

lift, along the Kaplan units and connect to a new second hopper. Reconstruct 

entrance B to the east fish lift at 45 degrees to the river flow (see figure 3-15).

• Phase III: If passage efficiency is not met in Phase I and II, make daily 

adjustments to minimum flows and turbine operation, construct an east fish lift 

auxiliary water supply of 4,325 cfs, and upgrade east fish lift equipment to allow a 

15-minute cycle time.

Figure 3-15. View of the east end of the Conowingo powerhouse showing the 

approximate locations of Interior’s recommended entrance modifications to 

the east fish lift (Source: Google Earth; Morales and Towler, undated; 

Staff). 

Exelon, in its reply comments, states that there is currently no need to construct 

additional fish passage facilities at Conowingo dam, that the recent shad population 

trends in the Susquehanna River and along the Atlantic coast do not indicate that large 

increases in shad populations are likely, and that there is no scientific basis for the target 
156

effectiveness rates that Interior and other agencies have recommended for fish passage 

facilities at Conowingo and the other Susquehanna River hydroelectric projects. Exelon 

also comments that past agency management decisions for the Susquehanna River have 

been flawed, including the decision to terminate shad trap and truck operations from 

Conowingo after 1996, resulting in a decrease in the number of spawners reaching 

upriver spawning habitat.

Our Analysis

Exelon conducted several studies as part of relicensing to assess the effectiveness 

of the existing fish lifts and to identify which operating conditions at the project resulted 

in the best fish passage. Exelon also conducted an engineering evaluation to assess 

alternatives for improvements to the facilities to improve fish passage. In addition to the 

current studies, there are more than 40 years of operational experience with the fish 

passage facilities at Conowingo dam, with a multitude of associated studies. Numerous

other studies and operational experiences at fish passage facilities for American shad and 

other anadromous species are also available for other projects on the Atlantic and Pacific 

coasts that may have some applicability to the Susquehanna River. Fish passage at 

Conowingo is one of the primary issues for relicensing, as passage at Conowingo has a 

major effect on fish passage upstream of Conowingo and on the restoration program for 

the Susquehanna River. Ultimately, the final fishway prescriptions from Interior and 

NMFS would become conditions of any license issued for Conowingo, but we are 

presenting our independent analysis of this issue at Conowingo, including our assessment 

of Interior’s preliminary fishway prescription.

Fishway Effectiveness

Fishway effectiveness is an important aspect of fishway operations on the 

Susquehanna River, as the objective is to pass as many spawners as possible to areas 

upstream of York Haven dam, where the best spawning habitat for shad occurs. Some 

spawning habitat is also available between the Safe Harbor and York Haven projects 

(about 12 miles of river), in some of the tributaries (such as the Conestoga River), and in 

limited areas in the upper reaches of Conowingo Pond and Lake Aldred (Holtwood 

reservoir). But the primary focus of the shad restoration program has always been a 

target population as measured at the York Haven Project. As stated in the current 

restoration plan for the river (SRAFRC, 2010), the goal of the program is: “Restore selfsustaining, robust, and productive stocks of migratory fish capable of producing 

sustainable fisheries, to the Susquehanna River Basin throughout their historic ranges in 

Maryland, Pennsylvania, and New York. The goals are 2 million American shad and 5 

million river herring spawning upstream of the York Haven Dam. Goals for American 

eel and other migratory species are yet to be determined.” In order to achieve that goal, 

the plan also states as a primary objective: “Develop and implement upstream passage 

plans and performance measures at all four lower river hydroelectric dams to ensure that 

each facility passes at least 75 percent of the adult American shad passed at the next 

downstream facility, or at least 85 percent of the adult American shad reaching project 
157

tailwaters.” The fishway effectiveness target has also recently been revised slightly by 

Interior to say that 80 percent of the fish in each tailwater must pass within 36 hours, to 

reduce delay at each project.54 The basis for these effectiveness targets is not provided in 

the restoration plan, but is believed to be a reflection of the effectiveness at the Safe 

Harbor Project, which has the highest effectiveness of any facility on the Susquehanna 

River (or perhaps on the Atlantic coast), averaging about 71 percent of the passage at the 

downstream Holtwood Project. Recent population modeling by both Exelon 

(Normandeau and Gomez and Sullivan, 2012j) and FWS (Sweka, 2014) also indicate that 

the most important factor in achieving a population growth in line with restoration goals 

is providing a sufficient numbers of spawners to upriver habitat. Without high fishway 

effectiveness or trucking of spawners to that habitat, the shad population would not 

substantially grow or reach restoration goals. This modeling also included hatchery 

contributions of shad fry, and while hatchery production may result in some population 

growth, the most important factor is providing sufficient numbers of spawners to upriver 

habitat (see discussion below on Susquehanna River Shad Population Trends).

While fishway effectiveness is important, we previously discussed our concerns 

about specific target effectiveness goals at the York Haven Project, and whether target 

effectiveness is something that can entirely be controlled by the licensees. At 

Conowingo, Exelon’s studies showed that the east fish lift attraction efficiency55 ranged 

from 73 percent in 2010 to about 44 percent in 2012 (Normandeau and Gomez and 

Sullivan, 2012a; 2012b). Total fish passage effectiveness56 ranged from 45 percent in 

2010 to 26 percent in 2012. Several variables were assessed for the two study years;

river flows and project discharges were generally higher in 2012 than 2010, possibly 

resulting in lower attraction efficiency in 2012. The portion of those fish that entered the 

fish lift and ended up successfully passing the fish lift was similar in both years (61.5 

percent in 2010 and 58.6 percent in 2012). This would be expected as once fish are 

inside the facility the hydraulic conditions are more controlled than what fish may 

experience in the river or tailrace. However, in both years fish made multiple forays, 

both successful and unsuccessful, into the fish lift and were detected in many areas of the 

tailrace, indicating searching behavior. 

This searching behavior results in delay of fish locating the fish lift entrances and 

achieving passage, and is a concern expressed by Interior and other agencies. Fish that 

 

54 However, Pennsylvania FBC has a slightly different criterion that 80 percent of 

the fish should pass a project within 5 days.

55 That is, the percentage of radio-tagged shad documented in the tailrace that 

subsequently entered the east fish lift. 

56 That is, the percentage of radio-tagged shad documented in the tailrace that 

successfully completed passage through the east fish lift.
158

experience delays in passing Conowingo and the other lower river hydroelectric projects 

may not reach upstream spawning areas in time to complete spawning, as Susquehanna 

River water temperatures typically increase quickly in late spring as river flows recede. 

FWS analyzed radio telemetry data from the 2010 and 2012 studies, to assess the amount 

of delay that fish encountered in entering and passing the east fish lift (Morales, undated). 

According to this analysis, fish in 2010 required from 3.5 hours to 383 hours (average of 

129 hours – about 5.4 days) from their initial entry into the tailrace (as detected by radio 

telemetry), for successfully completing passage into Conowingo Pond, and only 10.1 

percent of the fish met the current Interior criteria that passage occur within 36 hours. In 

2012, fish required from 56 hours to 768 hours (average of 276 hours – 11.5 days) for 

completing passage, and no fish met the Interior criterion that passage occur within 36 

hours. 

We are unsure of the basis for the Interior 36-hour criteria, and what an acceptable 

delay may be. To further assess potential “acceptable” delays, we examined water 

temperature data from the Harrisburg USGS gage (No. 01570500), located just upstream 

of York Haven, for 2008 through 2013 (data not available for 2011), to determine when 

water temperatures typically reach the upper range of most suitable spawning 

temperatures for shad (71°F – Walburg and Nichols, 1967). The assumption is that once 

the maximum suitable temperature is reached and maintained and then exceeded, there 

would be little successful spawning after that point. In reality, however, some spawning 

would likely continue at higher temperatures, as Walburg and Nichols (1967) report that 

spawning may occur at temperatures as high as 78°F. The following summarizes when a 

temperature of 71°F was first reached and then maintained at Harrisburg:57

• 2008 – May 31

• 2009 – June 7

• 2010 – May 26

• 2012 – June 9

• 2013 – May 28.

Conowingo dam typically begins fish lift operations by about April 1, although 

substantial numbers of shad are usually not available until mid-April. An approximate 

average of the above dates when water temperatures would exceed 71°F would 

conservatively be about May 31, which would mean that shad reaching Conowingo dam 

in mid-April would need to pass York Haven in about 45 days. This would mean that 

 

57 There were instances when this temperature was reached for a short time, but 

then decreased after a few days as a result of colder weather or higher flows. We used 

the date when the temperature first reached 71°F and then remained above that for a 

prolonged period.
159

fish would need an average of about 10 days to pass each project dam and migrate the 

distance between each project.58 For later arriving fish, however, this window would be 

shorter, with fish arriving by May 1 having a 30-day window, needing to pass each 

project in an average of about 7 days. If we subtract the travel time (5 to 6 days – see 

footnote below), this would further reduce the window at each project to an average of 

about 6 days for fish to locate and successfully pass the fishway at each dam. While we 

understand Interior’s objective to reduce delay at each project, our simple analysis 

indicates that Interior’s 36-hour criteria may be overly conservative, and that fish could 

still reach habitat upstream of York Haven at suitable spawning temperatures as long as

they could pass each project within a matter of days. Our estimate is more in line with 

the Pennsylvania FBC criteria that 80 percent of the fish pass a project within 5 days.

In any event, the fish passage effectiveness at Conowingo dam, based on Exelon’s 

studies, appears relatively low (45 percent in 2010 to 26 percent in 2012), with average 

delay ranging from 5.4 to 11.5 days. While this effectiveness may be within the range of 

other fish passage facilities in the Northeast (such as Holyoke dam on the Connecticut 

River), the Holyoke dam is located at RM 86, and has suitable and ample spawning 

habitat both downstream and upstream of the dam. On the Susquehanna River, fish must 

pass four dams before reaching the best spawning habitat. 

The best example of a multiple-dam system that has an established healthy shad 

run is the Columbia River, although the American shad is an introduced species in the 

Columbia River and is not a management species of interest. The Columbia River shad 

runs have reached more than 6 million fish annually, probably the largest run in North 

America, and the hydroelectric projects have large fishways designed for salmon with 

high volumes of attraction water not typically seen in Atlantic coast projects. Table 3-23

summarizes American shad counts on the Columbia River for three lower-river dams: 

The Dalles, John Day, and McNary. Bonneville dam is the lowermost dam on the river, 

but because a large segment of the shad run passes through the navigation lock at 

 

58 The distances between projects on the lower Susquehanna River, however, are 

not large, although fish would also have to pass by the Muddy Run Project. With 

Conowingo dam at river mile 10 and York Haven dam at river mile 54, shad would only 

need to travel 44 river miles to reach York Haven. At a shad cruising speed of about 3 

fps (2 miles per hour) (Bell, 1991), an unobstructed shad could travel 44 miles in about 

22 hours (about a day), if it migrated continuously. However, Normandeau and Gomez 

and Sullivan (2012h) reported much slower migration speeds in Conowingo Pond of 4 to 

6.7 miles per day. At an average speed of 5 miles per day, fish would require about 

9 days to reach York Haven. Because the 44-mile-reach is a combination of reservoir 

and riverine habitat, we assume that travel time to York Haven may be in the range of 5 

to 6 days, for a freely-migrating shad.
160

Bonneville (resulting in higher counts at the next upstream dam, The Dalles), we are 

using The Dalles counts as the “beginning” count on the Columbia. 

While some shad may use navigation locks for passage at all the dams on the 

Columbia River, the fishway counts at The Dalles and above dams are believed to 

reasonably represent shad passage at these dams. These data show that John Day dam 

passes an average of 51 percent of the count at The Dalles (range of 27 to 70 percent), 

and McNary dam passes an average of 55 percent of the John Day passage (range of 32 

to 108 percent [potential counting error]). The Dalles reservoir is about 24 miles long, 

and John Day reservoir is about 76 miles long, and both reservoirs may contain suitable 

shad spawning habitat. The passage at McNary dam averages 28 percent of the passage 

at The Dalles (range of 13 to 58 percent). These data show that there has been a wide 

range in passage effectiveness through the years, but the long-term average is that about 

50 percent of the fish passed at the lower dam is passed at the next upstream dam. These 

long-term data show that the target passage effectiveness recommended for the 

Susquehanna River (75 percent from dam to dam) has only been occasionally met on the 

Columbia River, and in most years is much less than that target. While the shad is not a 

target species of interest on the Columbia River, the Corps and fisheries agencies still 

have an interest in effectively passing the shad at each dam, so that shad successfully 

move through the fishways and do not affect or block the passage of the salmonid species 

of interest, many of which are federally listed. Consistently maintaining a high fish 

passage effectiveness (75 percent) on all the Susquehanna River projects, as 

recommended by Interior and other commenting entities, may not be a realistic objective, 

but as fish counts on the Columbia River have shown, somewhat lower passage 

efficiencies may still result in substantial growth and maintenance of a large shad 

population (table 3-23). 

Table 3-23. American shad passage at lower Columbia River dams, and passage 

effectiveness between dams, 1984 to 2013 (Source: http://www.fpc.org/, 

accessed March 22, 2014).

Year The Dalles 

(RM 192)a

John Day 

(RM 216)

JD % of 

The Dalles

McNary 

(RM 292)

McN % of 

John Day

McN % of 

The Dalles

2013 --b -- -- 1,246,494 -- --

2012 -- -- -- 675,421 -- --

2011 -- -- -- 224,905 -- --

2010 1,241,770 -- -- 276,673 -- 22

2009 1,641,362 -- -- 486,725 -- 30

2008 1,805,516 -- -- 623,010 -- 35

2007 3,591,988 -- -- 985,466 -- 27

2006 4,611,592 -- -- 1,176,899 -- 26
161

Year The Dalles 

(RM 192)a

John Day 

(RM 216)

JD % of 

The Dalles

McNary 

(RM 292)

McN % of 

John Day

McN % of 

The Dalles

2005 6,067,028 -- -- 1,951,001 -- 32

2004 5,472,400 -- -- 1,751,728 -- 32

2003 4,258,889 2,735,108 64 1,077,670 39 25

2002 3,218,050 1,850,942 58 599,294 32 19

2001 2,724,946 1,796,826 66 1,063,568 59 39

2000 1,556,619 851,598 55 350,457 41 23

1999 1,718,679 763,007 44 248,895 33 14

1998 2,149,097 1,025,044 48 393,305 38 18

1997 2,571,260 1,007,896 39 340,090 34 13

1996 2,648,553 959,262 36 352,755 37 13

1995 1,959,564 1,033,727 53 481,081 47 25

1994 1,801,545 935,958 52 668,528 71 37

1993 2,394,394 647,097 27 701,404 108 29

1992 2,824,313 1,963,060 70 1,635,089 83 58

1991 2,191,077 1,382,009 63 674,483 49 31

1990 3,706,855 1,641,943 44 866,940 53 23

1989 2,971,017 1,773,938 60 1,076,473 61 36

1988 2,008,572 908,741 45 665,925 73 33

1987 1,289,698 748,767 58 575,338 77 45

1986 1,361,854 609,363 45 307,361 50 23

1985 1,389,547 682,344 49 438,329 64 32

1984 1,135,982 586,015 52 281,793 48 25

Average % 51 55 28 a Bonneville dam is at RM 146.

b The Corps ended shad counts at The Dalles in 2011 and at John Day in 2004.
162

Susquehanna River American Shad Population Trends

The resource agencies and cooperating project owners have made progress in 

restoration of shad to the Susquehanna River over the past 40 years. As described in 

Susquehanna River Anadromous Fish Restoration Cooperative (SRAFRC, 2010), the 

number of shad collected annually in the west fish lift generally numbered in the 

hundreds of fish in the 1970s and early 1980s, and did not consistently exceed 1,000 fish 

until 1985. As table 3-13 shows, the numbers of shad passed at Conowingo increased 

substantially into the late 1990s with the completion of the east fish lift and reached a 

peak of 193,574 in 2001. Since 2001, however, the numbers have consistently declined. 

Maryland DNR has also been making shad population estimates for the Conowingo 

tailrace since the 1980’s (SRAFRC, 2013), using both a Petersen mark/recapture 

methodology and surplus production method (SPM).59 These estimates are shown in 

figure 3-16, and show a similar trend to the fish lift counts, with strong population growth 

up until 2000 to 2001, with an overall decline since then. The Petersen estimates show 

much higher numbers than the SPM method in some years, believed to be because of 

very low recapture rates in some years. Both methods show a small increase in 

population estimates from 2007 to 2012. In 2012, Maryland DNR estimated a tailrace 

shad population of 150,743 fish using the Petersen method and 111,500 fish using the 

SPM.60 Maryland DNR finds that the Petersen method may overestimate the actual 

population size, while the SPM may underestimate the population, but also indicates that 

the cessation of trucking in 1997 has been a factor in the decline of the shad population in 

the lower river (SRAFRC, 2013). 

 

59 The SPM is a mathematical technique in which the population estimate is based 

on the previous-year’s population, the intrinsic rate of population increase, the estimated 

maximum population size, and assumed losses associated with upstream and downstream 

fish passage and by-catch mortality in the Atlantic herring fishery in the previous year.

60 The east fish lift passed 22,143 shad in 2012, or about 15 percent of the Petersen 

population estimate and 20 percent of the SPM estimate. An additional 1,486 shad were 

collected in the west fish lift and used for egg collections and other experimental 

purposes. 
163

 

Figure 3-16. Maryland DNR American shad population estimates for the Conowingo 

tailrace, 1986 to 2012 (Source: SRAFRC, 2013). 

Other factors in the decline may include the strong growth of the gizzard shad 

population, the increase in the number of predators in the river (including the introduction 

of the flathead catfish), and continued harvest of shad in offshore fisheries. Table 3-14 

illustrates the strong increase in the gizzard shad population in the river, with annual 

passage at the Conowingo east lift now reaching more than 1 million gizzard shad, and an 

additional 300,000 to 400,000 gizzard shad taken in the west lift. The effects of 

crowding in the fish lifts are unknown but there is the potential that large numbers of 

gizzard shad may delay or hinder American shad entry to the lifts. Another effect of 

gizzard shad on American shad and other species that rely on zooplankton as a food 

source for early life stages (larvae and juveniles), is that large numbers of larval and 

juvenile gizzard shad may have an adverse effect on zooplankton populations via 

extensive grazing of that population (Sullivan et al., 2011). With a large population of 

juvenile gizzard shad in the lower river, interspecific competition for that food source 

may affect the growth and survival of juvenile American shad. The effects of a voracious 

predator such as flathead catfish has not been quantified, but this invasive species is now 

regularly caught throughout the lower river, with hundreds now typically collected in the 

Conowingo lifts and in the York Haven east channel ladder, and is also recorded in the 

Holtwood and Safe Harbor fish lifts (SRAFRC, 2013). Flathead catfish has also now 

become a target species of interest for anglers in the Susquehanna River, and the 

Pennsylvania FBC reports that flathead catfish in excess of 40 pounds are commonly 
164

caught within Pennsylvania (http://www.fish.state.pa.us/catfish_flathead.htm, accessed 

May 15, 2014). An offshore ocean fishery for American shad, both directed and bycatch, continues along the Atlantic coast, although that fishery has shown declines as the 

stocks have reached lower levels and with the closure of an ocean intercept fishery in 

2005.61 Because of its concern about this continued source of mortality to American shad 

stocks, including the Susquehanna River, the Atlantic States Marine Fisheries 

Commission (ASMFC) has adopted a strategy to quantify and manage sources of bycatch mortality where possible (ASMFC, 2010). 

Several comments have been made by both the agencies and Exelon that the 

cessation of trucking to upriver habitat has been a factor in the recent decline of the shad 

population, and that reinstatement of some trucking would likely benefit the population 

by “jump-starting” population growth. We further examined this issue by summarizing 

the total number of spawners reaching upriver habitat by trucking from the east and west 

fish lifts since the beginning of the program, as well as out-of-basin trucking,62 and 

compared that to the number of spawners reaching upriver habitat since volitional 

passage was established at all the dams in 2000. Table 3-24 and figure 3-17 show that 

the number of spawners reaching upriver spawning habitat since trucking was eliminated 

in 2000 has decreased significantly, particularly after 2001. Based on these data, it is 

likely that the recent decrease in the shad numbers at Conowingo is related to the 

significant decrease in spawners reaching upriver habitat. The peak number of upstream 

spawners occurred from 1994 to 1996, followed by peak returns to the east lift in 2000 to 

2004, from 4 to 8 years after the peak number of upstream spawners occurred. Most shad 

return to spawn at ages IV to VII, with some age VIII fish reported (SRAFRC, 2013). To 

illustrate the potential benefits of trucking, simple math shows that if fish are allowed to 

pass the three dams upstream of Conowingo via volitional passage at 75 percent 

effectiveness at each dam, only about 42 percent of the fish exiting the Conowingo fish 

lifts would reach above York Haven. In contrast, 100 percent of the fish trucked from 

Conowingo would reach habitat upstream of York Haven, minus any mortalities in 

transport, which in past trucking operations were minor. A sustained trucking program 

would have the potential to maintain greater numbers of spawners in upriver locations 

when the shad population is low, as now, than volitional passage over four dams.

 

61 An ocean intercept fishery is a commercial fishery in the ocean directed at 

stocks of migratory fishes on their way to spawning streams. 62 From 1980 to 1987 pre-spawn shad were trucked to the Susquehanna River from 

other river basins (most from the Delaware River).
165

Table 3-24. Number of American shad spawners, from multiple sources reaching 

upriver spawning habitat (primarily upstream of York Haven), 1980 to 

2014 (Source: SRAFRC, 2010; Pennsylvania FBC, 2014).

Year

Out-of-basin 

Trucking

Trucking from 

Conowingo

Volitional 

Passage to 

York Haven

Total 

Spawners

1980 114 -- -- 114

1981 1,165 -- -- 1,165

1982 2,565 800 -- 3,365

1983 4,310 64 -- 4,374

1984 3,777 0 -- 3,777

1985 2,834 967 -- 3,801

1986 4,965 4,172 -- 9,137

1987 6,051 7,202 -- 13,253

1988 -- 4,736 -- 4,736

1989 -- 6,469 -- 6,469

1990 -- 15,075 -- 15,075

1991 -- 24,662 -- 24,662

1992 -- 15,674 -- 15,674

1993 -- 11,717 -- 11,717

1994 -- 28,681 -- 28,681

1995 -- 56,370 -- 56,370

1996 -- 33,825 -- 33,825

1997 -- 10,528 -- 10,528

1998 -- 4,593 -- 4,593

1999 -- 5,508 -- 5,508

2000 -- 1,351 4,675 6,026

2001 -- -- 16,200 16,200

2002 -- -- 1,555 1,555

2003 -- -- 2,536 2,536

2004 -- -- 219 219

2005 -- -- 1,772 1,772
166

Year

Out-of-basin 

Trucking

Trucking from 

Conowingo

Volitional 

Passage to 

York Haven

Total 

Spawners

2006 -- -- 1,913 1,913

2007 -- -- 192 192

2008 -- -- 21 21

2009 -- -- 402 402

2010 -- -- 907 907

2011 -- -- 0 0

2012 -- -- 224 224

2013 -- -- 202 202

2014 -- -- 8 8
167

Figure 3-17. Graphical depiction of number of American shad spawners, from multiple 

sources reaching upriver spawning habitat (primarily upstream of York 

Haven), 1980 to 2014 (Source: SRAFRC, 2010; Pennsylvania FBC, 

2014). 

Hatchery production of shad has also been a part of the Susquehanna River 

restoration program since 1976. Fertilized American shad eggs have been collected over 

the years on several rivers on the Atlantic coast (Susquehanna, Delaware, Connecticut, 

Hudson, Potomac, York, James River and its tributaries) and from the Columbia River in 

Oregon/Washington. In recent years, egg-taking has also occurred at the west fish lift via 

artificial tank spawning. Since the Pennsylvania FBC Van Dyke hatchery went into 

operation in 1976, more than 220 million shad fry and juveniles (mostly fry) have been 

stocked into the Susquehanna River and its tributaries, ranging on an annual basis from 

660,000 to 13.5 million. In the last 5 years the numbers stocked have ranged from about 

2.5 to 5.5 million, totaling 18.6 million, almost exclusively fry. SRAFRC (2013) 

estimated that for the 1986-2007 year classes, stocking of approximately 404 hatchery 

larvae was required to return one adult to the Conowingo lifts. Assuming that 400 fry are 

required for each adult return, stocking in the past 5 years could result in a return of about 

46,500 adult shad to the lifts, but spread over 4 to 5 years and longer. For trucked fish, 

SRAFRC (2013) estimated that transport of 1.28 adults to upstream areas was required to 

return one wild fish to the lifts. Thus, 59,520 fish would need to be trucked to produce a 

return of 46,500 fish. However, past experience has shown that up to 56,000 fish were 
168

trucked in 1 year (see table 3-24), so this production could occur in 1 year, instead of 

being spread over 5 years, as with the recent hatchery program. Even a more modest 

trucking program of 30,000 fish per year over 5 years (stocking of 150,000 spawners) 

would result in the production of about 117,000 returning adults to the lifts, using current 

survival rates. A modest trucking program would have the potential to produce more 

adult returns than a hatchery program similar to that of the recent 5 years. Actual 

survival rates and adult returns to the Conowingo tailrace may even be higher, however,

than estimated by SRAFRC because not all returning adults successfully enter the lifts. 

Atlantic coast and Chesapeake Bay American shad population trends

The current decline in shad populations on the Susquehanna River parallels 

declines that have been occurring coast wide, including in the Chesapeake Bay. A report 

by the Chesapeake Bay program 

(http://www.chesapeakebay.net/indicators/indicator/american_shad_abundance, accessed 

March 26, 2014) states that in 2013, the Bay-wide shad restoration program reached 

41 percent of its goal, but most of the increase in recent years has been due to the 

improvement in the Potomac River shad run. The recent trend for all the other major 

tributaries to the Bay has been either a decline or continued maintenance of low levels 

well short of the goals. These other rivers include the York, James, Rappahannock, and 

Susquehanna. Fish passage impediments were removed on the James River (Bosher’s 

dam fishway) and on the Rappahannock River (removal of Embrey dam) some years ago, 

but shad populations has not responded as expected to this increased availability 

of habitat.

For other Atlantic coast rivers, ASMFC (2010) reports that shad populations in 

most of the Atlantic coast rivers remain at historic lows and are not recovering to 

acceptable levels. ASMFC (2010) notes that data on annual numbers of fish passing 

upriver at dams on several Atlantic coastal rivers showed a coast-wide pattern of an 

increase followed by a decrease in the past 20 to 30 years. In fact, most fish passage 

numbers declined at about the same time (beginning in the late 1990s to early 2000s). 

This simultaneous decline suggests a coast wide change in environmental conditions or

mortality factors that affected stocks from South Carolina to Maine within the last 5 to 10 

years. This suggests that operation of hydroelectric projects on Atlantic coast rivers, 

many of which have fish passage facilities, have not been a primary cause of the 

population declines observed, and that additional or more effective fish passage facilities 

on these rivers may not necessarily result in population increases. 

Interior preliminary fishway prescription and improvements to Conowingo 

fish lifts

As described above, in its preliminary fishway prescription, Interior specifies

major renovations to the Conowingo fish lifts. Other agencies and other entities also 

generally recommend major renovations to the lifts to improve the effectiveness of the 

lifts, but only Pennsylvania FBC provides specific step by step recommendations for fish 
169

lift improvements. Table 3-25 summarizes the recommended improvements by Interior 

and Pennsylvania FBC.

Table 3-25. Summary of Interior preliminary fishway prescription and Pennsylvania 

FBC recommendations for upstream anadromous fish passage at 

Conowingo dam (Source: Interior and Pennsylvania FBC terms and 

conditions; Staff).

Interior preliminary fishway 

prescription

Pennsylvania FBC recommended 

improvements

Phase I: Construct a new west fish lift for 

both trap and trucking and direct volitional 

upstream shad passage (two 6,500-gallon 

hoppers), with an auxiliary attraction water 

system of 2,600 cfs. The objective would 

be to truck 50,000 adult shad per year. 

Create a 5,000-foot zone of passage on the 

east and west shores of the tailrace below 

the dam. Implement maximum 

downramping rate of 20,000 cfs/hour. 

Make channel modifications downstream to 

eliminate stranding in the spillway.

Timeline: No schedule given, but we 

assume 1 year for design and 2 years for 

construction, for total of 3 years.

Item 1: Incorporate performance criteria 

into new license where 80 percent of the 

shad that enter the project area must pass 

the project within 5 days, to be based on 

telemetry study of 150 shad per year for 3 

years. If goal is not reached, initiate 

operational changes as specified by the 

agencies and test for 3 years using 

telemetry study. If goal is still not reached 

after 3 years, make structural changes to 

the fish lifts as specified by the agencies, 

and test for an additional 3 years using a 

telemetry study. If goal is still not reached 

within 3 years, additional structural 

changes may be required, depending on 

behavior of tagged shad.

Timeline: Potential for 12 years – 3 years 

for initial studies, 3 years for study of 

operational changes, 3 years for structural 

changes, and 3 years for additional 

monitoring. 

Phase II: Modify the east fish lift stilling 

basin to allow 900-cfs attraction flow, as 

originally designed. Relocate east fish lift 

entrance A to upstream of the Kaplan unit 

boils. Construct new entrance D and 

collection gallery to east fish lift, along the 

Kaplan units and connect to a new second 

hopper. Reconstruct entrance B to east fish 

lift at 45 degrees to the river flow (see 

figure 3-15).

Item 2: Modify east fish lift to include a 

larger hopper, increased attraction flow, 

and addition of a collection gallery in front 

of units 8-11. 

Timeline: No schedule given as to when 

improvements would be required in relation 

to item 1, but we assume these would be 

the structural changes that would occur 

after the first 6 years of studies. Assume 1 

year for design and 2 years for 

construction. Similar to Interior Phase II. 
170

Interior preliminary fishway 

prescription

Pennsylvania FBC recommended 

improvements

Timeline: To begin when new west fish lift 

begins operation; we assume 1 year for 

design and 2 years for construction, for 

total of 3 years

Phase III: If passage efficiency is not met 

in Phase I and II, make daily adjustments to 

minimum flows and turbine operation, 

construct an east fish lift auxiliary 

attraction water supply of 4,325 cfs, and 

upgrade east fish lift equipment to allow a 

15-minute cycle time. 

Timeline: No timeline given but we 

assume 1 year for design and 1 year for 

construction, for total of 2 years.

Item 3: Complete the rebuild of the west 

fish lift to include additional attraction 

water and provision to expand to volitional 

passage if needed. Ultimately, fish passage 

facilities at Conowingo will need to pass a 

design population of 5 million fish, and fish 

lifts will be required on both sides of the 

tailrace.

Timeline: No schedule given as to when 

improvements would be required in relation 

to item 1, but we assume these would be 

the structural changes that would occur 

after the first 6 years of studies. Assume 1 

year for design and 2 years for 

construction. Similar to Interior Phase I.

Item 4: Telemetry study of gizzard shad is 

needed to understand the issues of passage 

efficiency, capacity, and interference with 

American shad, and the recycling of 

gizzard shad in the west fish lift.

Timeline: No schedule given but we 

assume a 1-year study during the first 3 

years of study in Item 1.

 

The Interior preliminary prescription and Pennsylvania FBC recommendations are 

similar in that they both call for the complete re-build of the west fish lift and major 

improvements to the east fish lift that would involve major structural changes. The 

Pennsylvania FBC recommendations differ from the Interior preliminary prescription, in 

that the Pennsylvania FBC appears to recommend that at least 6 years of radio telemetry 

studies first be conducted to determine fish passage effectiveness before structural 

changes are made, and after first studying operational changes for 3 of those 6 years. 

Interior does not specify any studies prior to making structural improvements, only after 

the improvements are made.
171

While we understand that the final Interior fishway prescription would become 

conditions of any license issued, the requirements to re-build both the east and west fish 

lifts do not appear to be justified at this time. Although we describe above that the 

effectiveness of the Conowingo fish lifts have not been high in two recent years of 

studies (2010 and 2012), we also find that other fish passage facilities for American shad 

have similarly exhibited a wide range of effectiveness, with some exhibiting low 

effectiveness. Even at Safe Harbor dam, which has demonstrated the highest 

effectiveness of the four fish passage facilities on the Susquehanna River (and perhaps of 

any fish passage facility on the Atlantic coast), has not met the minimum Interior criteria 

in many years. The current declining trend in the shad population in the Susquehanna 

River and elsewhere along the Atlantic coast also does not indicate that the existing fish 

passage facilities will be exceeding their current design capacity for American shad 

anytime soon. There is, however, a concern about the continuing increase in the gizzard 

shad population in the Susquehanna River, and the ability of the current lifts to handle 

that population.

Other concerns are that the existing facilities have not been well maintained by 

Exelon, are showing their age, and have not been operating as originally designed. For 

example, the west fish lift first began operation in 1972 for a 5-year period, and is still in 

operation, but with a hopper that is relatively small and that has the capacity to hold 

fewer numbers of fish than desired in light of current fish populations in the tailrace 

(particularly gizzard shad). The east fish lift was designed to operate with an attraction 

flow of 900 cfs (about 1 percent of the full Conowingo station capacity of about 86,000 

cfs), but because of excessive turbulence within the fish lift at that flow, and issues with 

some of the gates, it now operates at an attraction flow of only 300 cfs (0.3 percent of full 

capacity). The west fish lift was designed with a total attraction flow of 300 cfs, so 

current total attraction flow at Conowingo is 600 cfs (about 0.7 percent of full capacity). 

Experience has shown that the Conowingo fish lifts are most effective when station 

discharge is much less than full capacity, so that the total attraction flow is a greater 

percentage of ambient station discharge. The Interior and NMFS criterion for attraction 

flow is that it should be from 3 to 5 percent of full powerhouse capacity (Towler and 

Orvis, 2013), which at Conowingo would range from 2,580 to 4,300 cfs. Towler and 

Orvis (2013) also provide a summary table of attraction flows at fish passage facilities 

along the Atlantic coast, and for the major fish passage facilities listed (including those 

on the Connecticut, Merrimack, Penobscot, and Santee rivers), Conowingo attraction 

flows are the lowest percentage of any of the major facilities. Conowingo also has the 

lowest attraction flows of the Susquehanna River fish passage facilities. Making 

structural modifications within the east lift to increase the east lift attraction flow to its 

original design capacity of 900 cfs would be a reasonable way to increase attraction to the 

east lift without having to make major changes to the lift associated with constructing a 

new attraction water supply system.

Another operational deficiency of the existing east fish lift is that entrance A, 

which faces the Kaplan units (numbers 8 through 11), is not usable when the Kaplan units 
172

are operating. The Kaplan units’ discharge drowns out the attraction flow from 

entrance A, resulting in the closure of that entrance when the Kaplan units are operating. 

Interior’s prescription would result in relocating entrance A to upstream of the Kaplan 

unit boils, to provide a better attraction flow jet to the quiescent area upstream of the 

boils (see figure 3-15). While this may have some merit, in that it would be similar to

one of the Safe Harbor dam fish lift entrances that operates with good effectiveness, this 

would involve a major modification of the east lift. An alternative approach would be to 

first restore the 900-cfs attraction flow, and determine whether that additional flow, 

combined with operational modifications with the Kaplan units, would provide better 

attraction to entrance A when the Kaplan units are in operation. If the attraction problem 

persists after restoration of the 900-cfs flow, then the feasibility of relocating the entrance 

could be investigated. Interior’s prescription would also require the reconstruction of

entrance B to a 45-degree angle to the river flow. This appears to be counter to normal 

Interior guidance that attraction flow should be parallel to river flow, but this is another 

entrance modification that could be investigated if restoration of the 900-cfs attraction 

flow does not produce improvements in attraction flow patterns.

Interior’s prescription would require and Pennsylvania FBC recommends 

construction of a collection gallery upstream of the Kaplan units’ discharge, with Interior

prescribing that the collection gallery be connected to a new second hopper, to increase 

the capacity of the east fish lift, in light of the large number of gizzard shad now being 

lifted, and to help meet the American shad design capacity. Addition of a collection 

gallery would also be a major modification to the east lift, and may not be warranted, 

based on the current population size and the questionable value of a collection gallery for 

shad. Few of the major passage facilities for shad on the Atlantic coast have collection 

galleries,63 and where small collection galleries have been installed (Holyoke and Turners 

Falls dams on the Connecticut River), shad primarily use the shoreline entrances and the 

gallery entrances have collected few fish and in some cases have been closed. The Safe 

Harbor Project, which has a similar size tailrace to Conowingo with a total hydraulic 

capacity of 110,000 cfs (larger than Conowingo), does not have a collection gallery and 

has the highest fishway effectiveness on the river. Construction of a collection gallery 

should be a last step in making improvements to the fish lift entrances at Conowingo, and 

only if the previously discussed steps (restoring 900-cfs attraction water, and 

reconstructing entrances A and B) are unsuccessful, and there is evidence that large 

numbers of shad are in the tailrace and not locating the entrances. The past operation of 

the east fish lift has shown the capability to collect and lift large numbers of shad 

(193,574 in 2001), so making a major modification such as a collection gallery should not 

 

63 The Columbia River projects that pass shad have collection galleries, originally 

built for salmon, but the extent of collection gallery use by shad has not been reported. 
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be required unless a preponderance of information indicates that large numbers of shad 

are not locating the entrances. 

The installation of a second hopper, however, is an east lift improvement that 

warrants consideration. The current hopper at the east lift has a stated design capacity of 

750,000 shad annually, and an unknown number of other species. As we illustrated in 

table 3-14, large numbers of adult gizzard shad are now lifted at Conowingo (and all the 

Susquehanna River projects), and the gizzard shad, which is only slightly smaller than the 

American shad, occupies much of the available space in the east-lift hopper. Addition of 

a second hopper, while it may not double the capacity at the lift, should provide an 

increase in capacity of at least 150 percent (Gomez and Sullivan and Normandeau, 2012). 

The original design of the east lift included the provision for adding a second hopper, so 

the space is there and no major modifications to the overall fish lift structure would be 

required. We have additional discussion of required hopper size below, under our 

discussion of west lift improvements.

Phase III of the Interior prescription also requires addition of an auxiliary 

attraction water supply of 4,325 cfs at the east lift (5 percent of the maximum

powerhouse discharge) if passage efficiency is not met in Phase I and II, and the 

modification of fish lift equipment to allow a 15-minute lift cycle time. While we do not 

agree that an auxiliary attraction water supply is needed at this time,64 we do agree that 

the fish lift should be able to achieve a lift cycle time of 15 to 20 minutes (the original 

design was to be a 15-minute cycle). Gomez and Sullivan and Normandeau (2012) report 

that the current lift cycle time is about 1 hour, which is inadequate for a fish lift that is 

handling millions of clupeids and other species annually. A shorter lift cycle time is 

needed to minimize the delay in lifting fish, and to reduce the potential for overcrowding 

the hopper on days of peak fish movement. Gomez and Sullivan and Normandeau (2012) 

state that one of the main reasons that the cycle time is about an hour is that the hopper 

floats when it is lowered back into the collection channel, and takes a while to fill with 

water and sink to the bottom. This has not been a major issue at other fish lifts on the 

Susquehanna and elsewhere, and it appears it could be easily remedied by the installation 

of hinge flap valves on the hopper floor.

Interior prescribes and Pennsylvania FBC recommends complete reconstruction of 

the west fish lift so that it can serve as a trap and truck facility and for volitional passage. 

Interior prescribes volitional passage at the same time that the trap and truck facility 

(50,000-fish capacity) is constructed with two large hoppers (6,500-gallon) and a 

2,600-cfs attraction water supply. Pennsylvania FBC does not specify the facilities 

required at the west lift, although it appears to also recommend a trap and truck facility 

 

64 As we describe earlier in this section, we conclude that the originally designed 

900-cfs attraction flow should first be restored and tested before making any major 

changes to the attraction flow system. 
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with the provision to expand to volitional passage if needed in the future, to meet the 

design population of 5 million shad at Conowingo. We agree that the west lift should be 

improved and used for trap and trucking of shad, but it is premature to completely 

reconstruct the lift on the scale that would be required by Interior’s prescription. Even in 

its current condition, the west lift continues to collect about 5 to 20 percent of the shad 

lifted at the east lift, with 2,030 collected in 2013 (16 percent of the east lift catch).65 

During the peak year of trap and trucking (1995) when about 56,000 shad were trucked 

upstream from Conowingo, about 12,000 shad were collected in the west lift and trucked 

upstream (21 percent of the total trucked). While trucking of shad has not occurred since 

the year 2000, the current fish sorting process at the west lift is labor-intensive and is

essentially the same process using the same sorting tank initially installed in 1972. Trap 

and trucking operations at more recently constructed fish lifts typically involve a more 

automated process where transported fish can be more efficiently delivered to the 

transport truck, reducing the stress on trucked fish. Modifying the west lift facilities to 

improve the sorting and loading process would be an important measure as part of the 

reestablishment of a trap and trucking program from Conowingo. While Interior would 

establish an objective to truck 50,000 shad per year, the peak shad catch for the west lift 

was about 16,000 fish in 1990, so the initial handling facilities could be sized with a 

lower capacity but use a design that could be expanded in the future if needed. 

Reestablishment of trap and trucking would also require purchase of trucks and transport 

tanks and associated aeration systems, unless some of that equipment is available from 

the previous program. 

Another prescribed west lift improvement would be replacement of the existing 

hopper, which has a volume of 900 gallons, or the capacity to hold 700 fish (1.3 gallons 

per fish) according to Gomez and Sullivan and Normandeau (2012).66 Interior has 

commented that the current hopper volumes at both lifts are inadequate for the design 

population and the other non-target species collected with shad (particularly gizzard shad 

that vastly outnumber American shad). Towler and Morales (2012) have estimated that 

using a design population of 2 million shad, and the Interior criterion of 0.10 cubic foot 

per pound of fish in a hopper, the required hopper size at Conowingo (total of both lifts) 

would range from 842 to 1,768 cubic feet (depending on whether a 1963 log-correlation 

or a 2011 regression is used). At 7.48 gallons per cubic foot, this would require hopper 

sizes of 6,298 gallons to 13,225 gallons (the Interior prescription requires hopper sizes of 

6,500 gallons at a new west lift). Towler and Morales (2012), however, also factor in a 

non-target species allowance (gizzard shad), which increases these hopper sizes by 9 

times with an 800 percent non-target species allowance. Towler and Morales (2012) 

conclude that sufficient hopper volume, as per the Interior criterion, cannot be achieved 

 

65 The west lift also collected 480,000 gizzard shad in 2013.

66 In contrast, the east lift hopper has a capacity of 3,300 gallons.
175

through any reasonable number of lifts at Conowingo, and recommend sorting as a way 

to eliminate nontarget species from the lifts. 

At the current hopper size and using the Interior criterion of 0.10 cubic foot per 

pound of fish, the west lift hopper with 900 gallons (120.3 cubic feet) would have a 

capacity of about 1,200 pounds of fish. The east lift hopper at 3,300 gallons (441.2 cubic 

feet) would have a capacity of about 4,400 pounds of fish. If we use a combined average 

weight of 2 pounds for American and gizzard shad,67 the west lift hopper has a capacity 

of about 600 fish and the east lift hopper has a capacity of about 2,200 fish. Gomez and 

Sullivan and Normandeau (2012) estimated that the current west lift hopper has a 

capacity of 700 fish (which would be an average weight of 1.7 pounds). Gomez and 

Sullivan and Normandeau (2012) also describe that the existing west lift hopper could be 

replaced with a larger 1,500-gallon hopper without changing the existing footprint of the 

west lift, although it would require changes in the steel superstructure and electrical and 

other mechanical components. This would have a capacity of about 2,000 pounds of fish, 

or about 1,000 fish using our calculations, and 1,150 fish as stated by Gomez and 

Sullivan and Normandeau (2012). While this would not meet the Interior prescription for 

a 6,500-gallon hopper (capacity of about 8,700 fish), the Interior prescription is well in 

excess of what is currently needed. A new 1,500-gallon hopper would increase the fish 

capacity by about 40 percent, which would be a substantial improvement over the 

existing hopper, particularly if hopper replacement is combined with structural and 

electrical/mechanical improvements, and an improved fish sorting and delivery system. 

Adding a second hopper of 3,300 gallons to the east lift as we describe above, would 

increase the lifting capacity of the east lift by an average of 2,200 fish, meaning that the 

total lifting capacity at Conowingo would increase to about 1,100 cubic feet (8,100 

gallons), with a fish lifting capacity of about 5,500 fish. Even if the lifts were only able 

to cycle at one lift per hour (which we believe should be shortened), this would provide a 

lifting capacity of about 55,000 fish over a 10-hour day, a substantial improvement over 

the existing capacity at Conowingo.

Interior’s prescription would require a major increase in attraction flows at the 

west lift to 2,600 cfs under phase I, and an increase in attraction flows at the east lift to 

4,325 cfs under phase III, as we previously discussed. A flow of 2,600 cfs would be 3 

percent of the powerhouse full capacity, while the combined attraction flows of 6,925 cfs 

would be 8 percent of powerhouse capacity. We previously discussed that it would be 

appropriate to increase the east lift attraction flow to its original design capacity of 900 

cfs. For the west lift, the current attraction flow is supplied by the house generating units, 

 

67 Walburg and Nichols (1967) state that male American shad average 2 to 3 

pounds, and female shad average 3 to 4 pounds. Gizzard shad are generally smaller than 

American shad, but larger gizzard shad do overlap in size with American shad. Morales 

(2013) uses an average weight of 1.2 pounds for gizzard shad.
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which provide on-site local power to the station, and is limited to about 300 cfs. This is a 

somewhat low attraction flow for the west side of the tailrace, and an attraction flow 

similar to the restored east lift flow (900 cfs) would be desirable, providing a total 

attraction flow from Conowingo of 2.1 percent, coming close to the Interior minimum of 

3 percent of total station discharge. In addition, if higher attraction flows could be 

provided during periods of lower generation, these attraction flows could be more 

effective in attracting shad during off-peak generation. Providing additional attraction 

flow at the west lift would require additional structures at the lift, because the current 

supply through the house units could not be increased. Tailrace pumps or additional 

withdrawals from the reservoir would be required, and it is not known if the existing lift 

structure could accommodate an additional 600 cfs through its entrance weir gates 

without modification. Gomez and Sullivan and Normandeau (2012) did not include an 

assessment of adding additional attraction flow to the west lift, so a feasibility study 

would be required before additional action could be taken on this measure.

Interior prescribes and Pennsylvania FBC recommends that the west lift be 

modified so that it could be used for direct volitional passage to Conowingo Pond. The 

Interior preliminary prescription appears to require volitional passage now, while the 

Pennsylvania FBC recommendation is that a new west lift be designed so that volitional 

passage could be provided later if needed. We agree with Pennsylvania FBC that there 

would be no immediate need for west lift volitional passage, which would be a 

challenging engineering project. The west bank has no easy access route to Conowingo 

Pond for a volitional fish passage facility because of the west dam embankment, the 

presence of U.S. Route 1 on the dam, and the administrative offices on the west end of 

the powerhouse. Any fish passage channel conveying fish to Conowingo Pond would 

need to tunnel through the dam embankment and under U.S. Route 1, or pass through the 

administrative offices. An alternative approach would be to dedicate the west lift to trap 

and trucking, egg taking, and experimental purposes, while the east lift would continue 

operating exclusively for volitional passage. Upstream project owners also have major 

investments in fish passage facilities, so it wouldn’t be appropriate to substantially reduce 

volitional upstream migration from Conowingo. The east lift has been shown to be 

capable of lifting large numbers of shad in the past, and if additional improvements are 

made as we describe, this capability should be enhanced. Enhancing the west lift for trap 

and trucking, as we discuss, would provide an important boost to the overall shad 

population if good numbers of shad can be successfully trucked to upstream habitat. A 

decision on volitional passage at the west lift could be postponed until all the project fish 

passage improvements (including trap and trucking) that we describe are implemented 

and are operated for a period of time, to determine (based on fish returns) whether any 

additional volitional passage is required, or whether trap and trucking is still needed. 

The Interior preliminary fishway prescription also includes in phase I the creation 

of a 5,000-foot zone of passage on the east and west shores of the tailrace below the dam, 

implementation of a maximum downramping rate of 20,000 cfs/hour, and channel 

modifications downstream of the dam to eliminate stranding in the spillway. Our review 
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of Exelon’s report on tailrace water velocities (Normandeau and Gomez and Sullivan, 

2012o) and several other studies conducted in the tailrace (such as shad radio telemetry 

studies in 2010 and 2012), found no indication of a blockage or substantial hindrance to 

migration associated with high water velocities. While high velocities were observed in 

the tailrace, there were also adequate zones of passage along the shoreline and in other 

locations, and none of the radio telemetry studies indicated that fish were unable to reach 

the powerhouse. While rapid downramping can cause fish stranding below hydroelectric 

projects, Exelon’s fish stranding survey did not find evidence of substantial stranding of 

target species downstream of Conowingo dam (Normandeau and Gomez and Sullivan, 

2012d). Although some fish stranding was observed, non-target species such as carp and 

gizzard shad comprised more than 90 percent of those observed. Total mortality of 

stranded fish ranged from 18 percent of the fish observed in the spring to 4 percent in 

other seasons. There appears to be little justification for requiring specific measures to 

prevent stranding below the dam. 

Pennsylvania FBC recommends additional effectiveness studies for 3 to 6 years 

before any structural improvements to the fish lifts are made. We find that this additional 

round of studies would be unnecessary. Exelon has decade’s worth of operational 

experience with the Conowingo fish lifts, and also conducted several studies during 

relicensing to address the fish passage issues. Sufficient information is available now to 

serve as the basis for fish passage improvements. We agree that additional effectiveness 

studies would be necessary to evaluate improvements made, but not prior to making the 

improvements. Pennsylvania FBC also recommends a gizzard shad telemetry study to 

understand the issues of passage efficiency, capacity, and interference with American 

shad, and the recycling of gizzard shad in the west fish lift.68 This would be an important 

study to better understand how the gizzard shad affects the passage of American shad in 

the Conowingo lifts.

Downstream Passage and Fish Entrainment 

York Haven Project

At each of the hydroelectric projects on the Susquehanna River, fish are 

susceptible to injury or mortality if they are entrained through the powerhouse turbines. 

Migratory fish species in the Susquehanna River that are susceptible to entrainment 

during their migration to the ocean include American shad, river herring (alewife and 

blueback herring) and American eel. River herring and American eel, however, have 

only been documented in the York Haven project area a few times since fish passage in 

the east channel became operational in 2000. Resident game fish including smallmouth 

bass, walleye, sunfish, and catfish that occur in the project area do not need to migrate 

 

68 Recycling means that fish enter the west fish lift, are sorted and released back to 

the tailrace, and then the fish re-enter the fish lift.
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downstream past the project to complete their life history, but these species may also be 

subject to entrainment through the project turbines.

Post-spawned adult American shad in the Susquehanna generally migrate 

downstream from June through mid-July, and juveniles migrate downstream from midSeptember through mid-November. Post-spawned river herring tend to migrate 

downstream during the late-spring and summer, and the juvenile outmigration extends 

into the early fall. Adult American eel migrate downstream in the fall. 

Under the terms of the Settlement Agreement, York Haven Power has agreed to 

implement several measures that are intended to or may serve to reduce fish entrainment 

mortality. These include: (1) increasing spill flows at the east channel and main dams 

during the American shad upstream passage season69; (2) continuing the current 

downstream juvenile American shad passage protocol, which schedules the operation of 

units 1-6 (Kaplan and propeller units) to be first online and last offline during the juvenile 

shad downstream migration period (which typically is from October 1 through November 

30); (3) pass about 370 cfs through the forebay sluice gate for 1 or 2 hours in the morning 

during weekdays if river flows exceed the sum of the turbine hydraulic capacity, flows 

through the nature-like fishway (once constructed), flows through the east channel, and 

flows (if any) over the main dam from May 1 through June 30 to facilitate downstream 

passage of post-spawning adult American shad; (4) pass about 370 cfs through the 

forebay sluice gate between the hours of 5 p.m. and 11 p.m. during the entire juvenile 

American shad passage period to facilitate downstream passage of juvenile American 

shad; and (5) develop designs within 4 years of license issuance for removal of 

obstructions in or deepening of the downstream plunge pool from the forebay sluice gate,

and a chute structure to convey flows beyond the roadway on the downstream side of the 

cable alley structure to protect outmigrating juvenile and adult American shad that land in 

the downstream pool.

Under the terms of the Settlement Agreement, York Haven Power also proposes to 

construct, operate, and maintain a nature-like fishway in the vicinity of the apex of the 

main dam and Three Mile Island in compliance with design criteria specified in appendix 

A of the Settlement Agreement. Upon completion of the nature-like fishway, York 

Haven Power proposes to implement several additional measures that may reduce fish 

entrainment mortality. These include: (1) conducting a juvenile American shad headrace 

turbine avoidance study; (2) if the juvenile American shad headrace turbine avoidance 

goals are not achieved, implement measures that would enhance the effectiveness and 

conduct a supplemental juvenile American shad headrace turbine avoidance study within 

 

69 The magnitude of these flows would vary depending on whether the nature-likefishway is in operation or not. Post-spawned shad begin downstream migration 

immediately after spawning, and could take advantage of increased spillage flow during 

the upstream passage season.
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2 years of implementing the measures; (3) provide an average daily minimum flow of 

267 cfs in the east channel below the east channel dam year round; (4) provide at least 5 

percent of river flow through the nature-like fishway and supplemental attraction flow 

channels when flows entering the project during the American shad upstream passage 

season are between 5,000 and 150,000 cfs; (5) provide a minimum flow of 200 cfs 

through the nature-like fishway when the river elevation is at the crest of the main dam 

and outside of the American shad upstream passage season; and (6) to the extent 

controllable by York Haven Power, when flows exceed the hydraulic capacity of all 

available generating units, manage flows to maximize flow over the main dam and the 

nature-like fishway.

Our Analysis

Currently, both migratory and resident fish species can move downstream past the 

project via four routes: (1) the powerhouse turbines, (2) the sluice gate located at the 

downstream end of the powerhouse, (3) the main dam spillway, and (4) the east channel 

dam spillway and gates. Once construction of the nature-like fishway has been 

completed, this will provide a fifth potential avenue for downstream passage.

As part of study 2.3, Assessment of American Shad at the York Haven Project, 

York Haven Power conducted a desktop assessment of turbine entrainment and mortality, 

which was included as Appendix G in the Initial Study Report. The assessment included 

a literature review of relevant fish entrainment and passage survival data applicable to the 

project and an evaluation of the flows passed via each potential passage route to assess 

the overall effects of entrainment and passage survival at the project.

Passage survival over the project spillways and sluice gate was evaluated by 

reviewing studies conducted at other low-head (equal to or less than 60 feet) non-turbine 

exit routes including sluices, spillways, and bypass pipes. These studies were conducted 

at seven different hydroelectric projects under a total of 17 different release locations or 

test conditions (head or spill volume). Survival rates estimated during these studies using 

the balloon-tag testing method ranged from 91 to 100 percent. Based on a comparison of 

site characteristics to the sites where the field studies were collected, York Haven Power 

concluded that the survival rate of fish passing the spillways and sluice gate at York 

Haven is likely about 97 percent.

York Haven Power used a variety of approaches to estimate the likely fish passage 

survival rates for fish that are entrained through the project turbines, based on an 

assessment prepared by Normandeau (2011), which was included as Attachment B of the 

desktop assessment. This included a review of site-specific data, analysis of comparable 

data from similar projects, and the use of a predictive turbine blade strike model 

developed by Franke et al. (1997). For outmigrating juvenile American shad, 

Normandeau estimated that the survival rate of juvenile American shad likely ranges 

between 83 and 98 percent at the six Kaplan units (units 1-6), and 66-92 percent at the 14 

Francis units (units 7-20). The available data for juvenile American shad included the 

results of site-specific tests conducted in 2000, which produced survival estimates of 92.7 
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percent at unit 3 and 77.1 percent at unit 7, both of which fell within the ranges estimated 

for Kaplan and Francis units, respectively. For outmigrating post-spawned adult 

American shad, Normandeau estimated that the survival rate likely ranges between 61 

and 91 percent at the Kaplan units (units 1-6), and 60-78 percent at the Francis units 

(units 7-20). The turbine blade strike model predicted that survival rates at all turbines 

would decline with increasing fish size, from about 95 percent for 4-inch fish to about 54 

percent for a 40-inch fish, the approximate maximum length for an adult American eel. 

More typical sizes for adult eels are from 18 to 30 inches (Scott and Crossman, 1973), so 

survival should be higher for the more typical sizes. 

The percentage of fish passing the project that are entrained through the 

powerhouse and subject to potential turbine entrainment mortality is likely to be roughly 

proportional to the percentage of the river flow that passes through the powerhouse. The 

hydraulic capacity of the project is exceeded about 60 percent of the time, and on average 

the proportion of the flow that passes through the project powerhouse varies from about 

23 percent in April to nearly 100 percent from July through September. However, fall 

rainstorms that increase Susquehanna River flows (and may trigger downstream 

migrations of juvenile shad and American eel) may also result in spillage at York Haven, 

providing for safe downstream passage. Each of the measures proposed by York Haven 

Power that would increase the amount of flow that passes the project via routes other than 

the turbines (including spillways, sluice gates and the nature-like fishway, once 

constructed) are likely to reduce the number of fish that are entrained through the turbines 

and subject to potential injury or mortality. York Haven Power’s proposal to remove 

obstructions in or deepen the plunge pool below the forebay sluice gate, and a chute 

structure to convey flows beyond the roadway, would help to ensure that fish passed via 

the sluice gate would be subject to minimal, if any, injury or mortality.

York Haven Power’s proposal is to continue the current downstream juvenile 

American shad passage protocol, which requires the operation of units 1-6 (Kaplan and 

propeller units) to be first online and last offline during the juvenile shad downstream 

migration period (which typically is from October 1 through November 30), and to pass 

about 370 cfs through the forebay sluice gate between the hours of 5 and 11 p.m. during 

the entire juvenile American shad passage period. This protocol would reduce 

entrainment mortality by reducing the amount of flow that passes through the Francis 

turbines and by increasing the proportion of fish that emigrate through the sluice gate, as 

opposed to the turbines. Conducting a juvenile American shad headrace turbine 

avoidance study and implementing any measures that may be needed to meet headrace 

turbine avoidance goals would further improve the survival rate of juvenile American 

shad passing the project.

York Haven Power’s proposal for downstream passage of post-spawned adult 

American shad is to pass about 370 cfs through the forebay sluice gate for 1 or 2 hours in 

the morning during weekdays if river flows exceed the sum of the turbine hydraulic 

capacity, pass flow through the nature-like fishway (once constructed), continue flow 

through the east channel, and utilize any spillage flow over the main dam from May 1 
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through June 30. During the radio telemetry monitoring conducted by York Haven 

Power in 2012 (York Haven Power, 2012b), 13 out of 59 adult American shad (22 

percent) that were documented passing the project passed through the forebay sluice gate. 

Continuing the operation of this sluice gate would ensure that a considerable portion of 

downstream-migrating adults can utilize this safe passage option, while other passage 

routes would provide additional options for safe passage.

Muddy Run Project

Downstream passage concerns at Muddy Run are somewhat different than at the 

other projects, because Muddy Run does not form a blockage to migration (like a dam), 

and fish do not require passage through the project to reach the ocean. The primary 

concern at Muddy Run is that downstream-migrating fish may be entrained and killed or 

pumped to the upper reservoir, and lost to the population. Resident species may also be 

entrained but few concerns were expressed by stakeholders about effects on resident 

fishes. Commenting agencies have generally recommended the same downstream 

passage survival rates at Muddy Run as recommended at the other projects (80 percent 

survival of adult shad and 95 percent survival of juvenile shad). Exelon states that it 

believes the downstream passage survival criteria are already met, but also has agreed to 

the Pennsylvania DEP certification conditions. Those conditions state that: (1) Exelon 

must submit a plan and schedule to provide for 95 percent survival of juvenile American 

shad and 80 percent survival of adult American shad that pass through the project area, 

with full implementation of the plan by 2015; (2) by February 15, 2026, or later, Exelon 

would be required to submit a plan to measure the passage of American shad moving 

downstream past the project to Pennsylvania DEP for approval (the “discrete passage 

study”); (3) Exelon would conduct the discrete passage study, and if results indicate that 

passage goals are met, specific operational measures or protocols would be incorporated 

into the FPOP to ensure that goals are continued to be met; and (4) if study results 

indicate that passage goals are not met, Exelon would propose a plan and schedule for 

mitigation to meet the passage goals. 

Our Analysis

We previously discussed the downstream migration of juvenile shad past the 

Muddy Run Project. Exelon’s studies estimated that for juvenile shad that were in the 

zone of influence during pumping, 22.6 percent of those fish could be entrained. For the 

overall population, however, Exelon estimated that only 2.9 to 6.6 percent of the 

population would be vulnerable to entrainment during peak outmigration times, because 

the project is not pumping during many of the peak hours of outmigration (Normandeau 

and Gomez and Sullivan, 2012g). These data indicate that the project essentially already 

meets the target effectiveness for downstream juvenile shad passage. The FWS review of 

Exelon’s study (Pugh, 2013) stated, however, that by adjusting the periods when juvenile 

shad may actually be passing the project, based on information from the scientific 

literature, the actual entrainment rate for juvenile shad would be from 12.3 to 14.5 

percent of the population, and not 2.9 to 6.6 percent as estimated by Exelon. Exelon, in
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its reply comments filed on March 18, 2014, states that the Pugh (2013) review of the 

data was flawed and that he overstates the actual effects of the project. We previously 

concluded that: (1) these conflicting studies and analyses and the argued differences in 

migration and entrainment rates may be within the range of error for the field studies and 

the data analysis; and (2) the studies and analyses have overall shown that the Muddy 

Run Project has not had an adverse effect on a major proportion of the shad population 

migrating downstream past the project. Interior also states, in an amendment to its 

preliminary fishway prescription filed on February 28, 2014, that while it believes that 

Muddy Run operation may affect fish migration, the effects may not be sufficient to 

affect the fisheries agencies goals for this reach of the river. 

In addition, with Exelon now agreeing to the conditions of the Pennsylvania DEP

certification, Exelon has committed to maintaining the effectiveness targets required by 

Pennsylvania DEP, would monitor this effectiveness via the studies required by the 

certification as part of its FPOP, and would mitigate any effects of the project if the target 

effectiveness is not maintained.

Conowingo Project

The Conowingo Project has the potential to entrain and injure or kill migratory 

fish moving downstream, as well as non-migratory species from Conowingo Pond. As is 

the case for the upstream hydroelectric projects, large numbers of American shad migrate 

past the project each year (although those numbers have decreased in recent years), while 

very few American eel and river herring occur upstream of Conowingo dam. Resident 

game fish species that are common in Conowingo Pond that may be subject to turbine 

entrainment include channel catfish, smallmouth bass, largemouth bass, walleye, green 

sunfish, pumpkinseed, bluegill, and white crappie. The reservoir currently supports a 

large population of gizzard shad as well as other species of forage fish, which may also 

be subject to entrainment.

Exelon proposes to continue to provide downstream passage via the project 

turbines at the Conowingo Project for juvenile and adult American shad. Interior, The 

Nature Conservancy, Pennsylvania FBC, and the Chesapeake Bay Foundation all 

recommend that Exelon implement measures to meet the downstream passage survival 

goal of 95 percent for juvenile American shad passing the Conowingo Project, as

specified in the SRAFRC 2010 Restoration Plan. The Nature Conservancy and the 

Chesapeake Bay Foundation further recommend that Exelon meet the 80 percent 

downstream passage survival goal for adult American shad established in the SRAFRC

2010 Restoration Plan.

Interior also recommends that Exelon develop an FEMP in consultation with 

Interior, to ensure that any changes in structure or operation as a result of relicensing 

continue to meet the survival goal for juvenile American shad of 95 percent. Interior 

recommends that Exelon provide an annual report detailing implementation of the FEMP 

to the resource agencies, including any deviations from the FEMP, followed by an annual 

meeting. Any required modifications to the FEMP would have to be submitted to the 
183

resource agencies within 30 days of receipt of a request for the modification unless a 

longer period is approved by Interior. The modifications to the FEMP would have to be 

implemented consistent with the approval of Interior.

In its reply comments, Exelon contends that relicensing studies demonstrate that 

the project meets the downstream targets requested by the parties and it is unnecessary to 

include these passage rates as conditions in the license.

Our Analysis

As part of Revised Study Plan 3.2, Exelon conducted a desktop study of turbine 

entrainment and mortality (Normandeau and Gomez and Sullivan, 2012i). The study 

included an assessment of the potential for fish impingement on the trashracks, 

assessment of entrainment potential based on habitat use, and estimation of passage 

survival rates for the Francis and Kaplan turbines at the project. The turbine passage 

survival assessment included a review of site-specific studies, analysis of comparable 

data from similar projects, and the use of a predictive turbine blade strike model 

developed by Franke et al. (1997).

To evaluate the potential for impingement on the trashracks, the desktop 

assessment included an evaluation of the swimming capability of American shad, 

American eel, and six representative resident fish species in relation to the approach 

velocity at the powerhouse trashracks, estimated fish widths, and trashrack spacing. The 

estimated approach velocity at the trashracks ranged from 2.4 to 3.7 feet per second at 

Units 1-11, which have trashracks with a 5.37-inch clear spacing. The two smaller house 

units have a clear spacing of 1.5 inches and an estimated approach velocity of 1.4 feet per 

second. The results of this analysis indicate that the potential for fish impingement at the 

project is minimal, because most larger fish would have sufficient swimming ability to 

avoid being swept into the trashracks, and smaller fish with lower swim speeds would 

likely pass through the trashracks and pass through the units. A possible exception is that 

larger channel catfish could be impinged, because they may have lower swimming speeds 

than other species, although no swim speed information was available. Results of the 

habitat use assessment indicated that entrainment potential was low for littoral species 

such as bluegill, largemouth bass and smallmouth bass because the bottom intakes are in 

the deepest part of the reservoir and not located near shallow water littoral areas where 

these species are typically found.

The desktop assessment also included an evaluation of turbine passage survival 

rates measured at other sites, but the results of these studies showed a wide range of 

values that are likely less informative than the results of site-specific testing that Exelon 

performed using juvenile and adult American shad.

Site-specific testing of turbine passage survival of juvenile American shad was 

conducted in 1993 (RMC, 1994) at one of the Kaplan turbines and in 2011 (Normandeau 

and Gomez and Sullivan, 2012n) at one of the Francis turbines using the balloon tag 

testing technique. Testing at the Kaplan turbine (unit 8) was conducted with a wicket 
184

gate opening of 55-56 percent, which was considered to provide less than optimal 

passage conditions, and resulted in a short-term (1-hour) survival estimate of 94.9 

percent. Testing of juvenile American shad passed through the Francis turbine (unit 5) in 

2011 resulted in a survival estimate of 89.9 percent. Testing at the Francis unit was 

conducted at near-peak efficiency, the setting the unit operates at most of the time when 

juvenile American shad would be moving past the Conowingo Project.

Site-specific testing of the turbine passage survival of adult American shad was 

conducted in 2011, also using the balloon tag testing technique (Normandeau and Gomez 

and Sullivan, 2012f). Testing was conducted at the Francis turbine (unit 2) at near-peak 

efficiency, and testing at the Kaplan turbine (unit 8) was conducted at a turbine discharge 

of 8,842 cfs (efficiency not given, but assumed to be near-peak). The resulting survival 

estimates for adult American shad passed through the Francis and Kaplan turbines were 

93.0 and 86.3 percent, respectively. The turbine passage survival rate of adult American 

shad was also estimated using the turbine blade strike model developed by Franke et al. 

(1997). The blade strike model predicted a survival rate of 79.8 to 90.4 percent for the 

Francis unit and 82.1 to 94.5 percent for the Kaplan unit.

The site-specific turbine passage survival rates estimated for adult American shad 

using the balloon-tag testing technique were consistent with survival rates estimated 

using the blade strike model, providing a reasonable degree of assurance that the passage 

survival rates for adult American shad meet or exceed the 80 percent downstream 

passage survival goal for adult American shad established in the SRAFRC 2010 

Restoration Plan. The site-specific passage survival estimated for juvenile American 

shad indicates that survival rates likely equal the downstream passage survival goal of 95 

percent at the Kaplan turbines, but are about 5 percent below this goal in the Francis 

turbines.

An FEMP, as recommended by Interior, would provide additional information on 

any variations in turbine passage survival associated with differences in operating 

conditions, and would provide an improved understanding of the survival rates of 

juvenile and adult American shad that are entrained through turbines at the Conowingo 

Project. Although the available data indicate that the passage survival rate for juvenile 

American shad through the Francis units may be about 5 percent lower than the passage 

survival goal of 95 percent, none of the stakeholders have suggested measures that may 

be feasible to improve passage survival in order to meet this goal. In the absence of any 

potentially feasible measures that could be implemented, the benefit of conducting 

additional testing of passage survival rates is unclear.

American Eel Passage 

Our previous discussion of upstream and downstream fish passage focused on 

anadromous species. Because American eel differ in life history (a catadromous species), 

behavior, and swimming ability, they require different types of passage facilities. 

Accordingly, we discuss American eel passage separately. 
185

York Haven Project

Eel passage has not been a major issue at York Haven because American eel have 

not occurred in appreciable numbers in the project area since construction of the lower 

river dams blocked upstream migration. American eel have occasionally been 

experimentally stocked in the upper river through the years, and recent studies and 

restoration efforts to date have been focused at Conowingo. Some eels collected at 

Conowingo have been transported to Susquehanna River tributaries upstream of York 

Haven (York Haven Power, 2011).70 

York Haven Power conducted a review of potential upstream and downstream eel 

passage measures at the project (York Haven Power, 2011), and included provisions for 

eel passage in the Settlement Agreement. No additional upstream fish passage measures 

are proposed for eels, because York Haven Power and the signatories to the Settlement 

Agreement believe that the proposed nature-like fishway and the low-head nature of the 

dam would provide adequate upstream passage. For downstream passage, York Haven 

Power would cooperate with the agencies and other project owners in a lower 

Susquehanna River downstream eel study to investigate the behavior and passage routes 

for migrating silver eels in the lower river and in the vicinity of York Haven. This would 

be a 2-year study to occur in about 2017-2020. York Haven Power would also conduct 

an eel survival study for passage through the turbines. If studies indicate that eel survival 

objectives are not met, York Haven Power would conduct a downstream eel 

improvements study, to identify measures that could be implemented to improve survival, 

to be followed by implementation and testing of those measures, and additional 

consultations as required.

Our Analysis

American eels do not occur in the project area in any numbers, with only 

experimental upstream stockings to date. Because upstream passage at downstream dams 

on the river would require several years to be implemented, it would be many years 

before upstream migrating eels arrive in the project area through volitional migrations. 

We agree that the nature-like fishway and the low-head configuration of the dam would 

likely provide for adequate upstream passage once upstream migrating eels arrive at the 

project. If trap and trucking of eels is implemented at Conowingo as proposed, it is likely 

that eels would be trucked upstream of York Haven in the immediate coming years.71 

These eels would remain in the river for 10-20 years before maturing to the silver eel 

 

70 FWS has been trapping and trucking eels from the Conowingo tailrace since 

2008, and transported about 300,000 eels through 2012.

71 Exelon would begin trap and trucking after issuance of any new license and 

would continue that program until 2029, when volitional passage would begin. 
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phase and out-migrate to the ocean. At that time, downstream passage over the project 

would be needed. 

The Settlement Agreement includes provisions for the eventual downstream 

passage of eels at the project, including studying the migratory pathways at the project 

and survival through the turbines, and then implementing protective measures if needed. 

These provisions of the Settlement Agreement would adequately protect downstream 

migrating eels once they arrive at the project. 

Muddy Run Project

American eel are not currently migrating through the Muddy Run Project area, as 

existing studies are focused downstream of Conowingo dam, and any experimental 

trucking has focused on upriver areas. However, the certification for the project has 

several measures related to eel, although many of those measures would be implemented 

at Conowingo. Exelon would be required to implement its American Eel Passage Plan 

with all measures to occur at Conowingo. Thus, we discuss those measures below under 

the Conowingo Project.72 For downstream passage, Exelon would comply with 

downstream eel passage rates of at least 85 percent through the Muddy Run Project area. 

However, the compliance date when that would be required is October 1, 2026, once 

sufficient numbers of eels have been released into the Susquehanna River to produce a 

substantial number of downstream migrating silver eels. Exelon would be required to 

conduct studies to demonstrate compliance with the passage rate, and if not achieved 

would be required to provide mitigation.

Both NMFS and Interior reserve their authority to require fishways during the 

term of the license, and Interior also provides a preliminary fishway prescription. For 

American eel, the preliminary fishway prescription requires an eel passage program with 

other licensees on the river, so that operation at Muddy Run does not interfere with 

passage objectives at the upstream Holtwood Project. The prescription also requires 

establishment of an Eel Passage Advisory Group within 6 months of license issuance, and 

an American Eel Passage Plan that would be implemented at the downstream Conowingo 

Project, which we discuss below.73 

 

72 Although mandatory conditions such as those contained in the certification 

would be requirements of any license issued, the Commission could not enforce a 

condition on another licensed project (Conowingo) through the Muddy Run license.

73 Interior does not specify the location of upstream eel passage facilities, only that 

immigrating juvenile eels be trapped “from a point downstream of the Muddy Run 

Project, and transport them to designated points in the Susquehanna River watershed.” 

We assume that this unnamed location would be the Conowingo dam tailrace, where the 

FWS has been conducting eel trapping investigations for more than 8 years.
187

For downstream passage, Interior requires a downstream eel passage study to 

evaluate the timing, magnitude, duration, annual variation and environmental conditions 

associated with active migration of silver eels from tributaries stocked with elvers, 

through the lower Susquehanna River and past the Muddy Run Project to the Chesapeake 

Bay. This study would be conducted for at least 2 years and would begin 3 years after 

license issuance. Concurrent with the downstream eel passage study or at a later date as 

approved by Interior, Exelon would also conduct a site-specific route of passage study to 

evaluate the entrainment rate of silver eels migrating in the vicinity of the project. If the 

results of the study indicate that the project’s existing operating measures do not meet the 

downstream passage criterion (survival of 85 percent of silver eels passing the project),

Exelon would prepare and submit a plan and schedule for evaluating the feasibility and 

costs of potential physical and/or operational modifications to the project to facilitate 

downstream eel passage.

Our Analysis

The downstream passage measures at Muddy Run required by both the 

certification (which Exelon has agreed to) and the Interior preliminary fishway 

prescription are similar, in that they both require monitoring studies of downstreammigrating silver eels past the project. If downstream passage survival criteria are not met, 

then operational or physical changes to the project would be required to mitigate any 

effects. Exelon has already conducted a radio telemetry study of silver eel passage past 

the Muddy Run Project (Normandeau and Gomez and Sullivan, 2012g), and found that 

nearly all the eels migrated past the project with minimal delay, and that the entrainment 

rate (i.e., pumped to the upper reservoir) was only 7 percent (exceeding the Interior 85 

percent passage survival criterion). Eels used in the study were transported from the 

Delaware River, because virtually no silver eels are currently available from the 

Susquehanna River upstream of Conowingo. 

The certification and Interior preliminary fishway prescription requiring later 

monitoring of downstream silver eel passage past the project is reasonable, although it 

would be more appropriate to conduct these studies farther into the future when “native” 

Susquehanna River silver eels are available for passage studies. The certification 

requirement appears to reflect that objective, in that it would not require such studies 

until after 2026 (at least 12 years into the future). The Interior preliminary fishway 

prescription, however, requires a 2-year study that would begin 3 years after license 

issuance. This would be much too soon to have substantial numbers of Susquehanna 

River silver eels available from any required trap and trucking operation (typical 

freshwater residence time is 10 to 20 years), and any such study would essentially be a 

repeat of Exelon’s recent study using eels from another river system. More valuable data 

would be collected if naturally migrating Susquehanna River silver eels were used in the 

study, instead of eels trucked from another river. 
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Conowingo Project

Exelon’s proposal for upstream passage at Conowingo is to construct an eel trap 

and transport facility on the west side of the tailrace, and cooperate with other licensees 

in implementing a trap and transport program for eel downstream passage from 

tributaries upstream of York Haven. As we discussed above, as part of the Interior

preliminary fishway prescription for Muddy Run, Interior is requiring an eel trap and 

transport program from downstream of Muddy Run (we assume Conowingo) to upstream 

locations. The Interior preliminary fishway prescription for Conowingo requires an eel 

trap and transport program beginning with a facility on the west shore of the Conowingo 

tailrace, to be completed within 1 year of completion of any construction at the west fish 

lift, or within 1 year of license issuance if no construction occurs at the west fish lift. 

This trap and truck facility would operate until 2029, and volitional passage would begin 

in 2030. Exelon would also be required to investigate a location for an eel trap on the 

east side of the Susquehanna River or in Octoraro Creek, and establish a temporary trap 

and truck facility within 2 years of license issuance and a permanent facility within 5 

years of license issuance. This trap and truck facility would be operated until 2029;

volitional passage would begin in 2030, we assume from a facility on the east side of the 

Susquehanna River below Conowingo dam. 

Interior included additional details on upstream eel passage in its Muddy Run 

preliminary fishway prescription that it did not include in its Conowingo preliminary 

fishway prescription. However, because it appears the Muddy Run preliminary fishway 

prescription actually applies to actions at Conowingo, we discuss those details here.74 

Interior requires Exelon to provide financial support to Interior of $20,000/year for its eel 

trapping facility at Conowingo dam until Exelon’s facility is completed. The prescription 

would require field testing to determine the best locations for eel traps, prior to 

construction of permanent traps that would consist of two ramp-style traps with capacity 

to pass 50,000 eels/day. Exelon would also be required to provide facilities for holding 

and transport and implement a quality assurance/quality control program to ensure that a 

target survival of 95 percent is achieved. An instream evaluation of the presence of eels 

in the river and tributaries would be required every 3 years, and a 2-year downstream 

passage study of silver eels would be required within 3 years of license issuance

(discussed above under Muddy Run).

The certification for Muddy Run also provides substantial detail for American eel 

passage in its specified American Eel Passage Plan. This plan is very similar to the 

Interior Muddy Run preliminary fishway prescription, requiring facilities at Conowingo 

 

74 As previously noted, although mandatory conditions such as those contained in 

a fishway prescription would be requirements of any license issued, the Commission 

could not enforce a condition on another licensed project (Conowingo) through the 

Muddy Run license.
189

and the detailed steps and schedules required. The certification also requires an eel trap 

and truck facility on the east shore, although it specifies that the facility be placed in 

Octoraro Creek, with the caveat that the location may be changed to other locations on 

the east side of the tailrace if the Octoraro Creek location is not successful. Similar to the 

preliminary fishway prescription, the certification also requires volitional passage at 

Conowingo, but states that will occur if the eel trap and transport program terminates in 

2030. 

Our Analysis

Because Exelon has accepted the conditions of the certification for Muddy Run, it 

has essentially also accepted the FWS preliminary fishway prescription, with some minor 

differences. As American eel restoration in the Susquehanna River is in its beginning 

stages, a phased approach for passage at Conowingo as agreed upon by Exelon, FWS, 

and Pennsylvania DEP is a reasonable way to proceed. We note that all parties have 

agreed to proceed with volitional passage at Conowingo at a fixed date in the year 2030. 

The assumption may be that over the next 15-year period the number of juvenile eels 

approaching the dam would increase to the point that trucking would no longer be a 

viable option, or that it may take that long to properly design and construct effective 

volitional facilities at all projects that may need them. The former may or may not be a 

good assumption, because even if the number of silver eels emigrating from the 

Susquehanna River increases over the next several years of trap and trucking, that would 

not necessarily translate into an increasing number of juvenile eels returning from the sea. 

Because American eel are thought to be one, well-mixed, single-breeding population 

(panmictic), the distribution of juvenile eels along the Atlantic coast is random with no 

homing to specific watersheds (Interior, 2007). A trap and trucking program may still be

viable past 2030 and would give managers the option to stock specific watersheds that 

may not be available with volitional passage, or in the event volitional passage facilities 

at the three lower Susquehanna River projects are not highly effective.

For downstream passage, Exelon is proposing to cooperate with other licensees on 

the lower Susquehanna River in implementing a trap and transport program and studies 

on eel passage from upstream of York Haven. Because essentially no silver eels are 

currently emigrating from the Susquehanna River, downstream eel passage is not a major 

issue at this time. It would be reasonable for Exelon and the other licensees on the river 

to cooperate in studies and in a possible trap and transport program for downstream 

passage, as more silver eels become available as a result of trap and truck efforts. If 

potentially good locations for trapping and trucking of silver eels are identified upstream 

of York Haven, or in tributaries upstream of any of the projects, such a program may be 

an effective measure for reducing mortality associated with downstream passage over the 

four lower-river dams. 
190

Freshwater Mussels

York Haven Project

Because substratum in the project area consists mainly of bedrock and large 

boulders and is subjected to frequent periods of elevated water velocity, this river reach 

provides little optimum mussel habitat. Based on sampling conducted in August 2010, 

five mussel species and 56 individuals were collected during 21.8 hours of searching; half 

of the sites yielded no live mussels. Weathered shells and shell material were observed 

along the shore and in shallow water, and there were no large deposits of fresh shells that

indicate presence of a nearby dense mussel assemblage. Although obtaining quantitative, 

total substratum sampling was not an objective of this survey, the fact that some small 

mussels were collected using qualitative methods indicates that conditions are suitable for 

limited mussel recruitment. 

The American eel is one of many other fish species that is host for eastern elliptio 

(Nadeau, 2008). Because eel passage is limited by the dams in the lower Susquehanna 

River, it is possible that distribution and abundance of eastern elliptio could be affected 

by lack of eels. Exelon proposes to develop a trap and transport program to restore 

passage of American eel to tributaries in the project area, which would likely start in two 

small tributaries upstream of York Haven dam that were previously stocked by FWS.

Our Analysis

The York Haven Project operates run-of-river and is not designed for flood 

control; therefore, downstream frequencies of major hydraulic events remain largely 

unchanged from pre-project conditions. There are no specific effects on resident mussels 

associated with operation of this project. The relatively low habitat value of the project 

area, compared with other reaches of the Susquehanna River, results mainly from existing 

conditions of substratum and water flow. 

In June 2010, York Haven Power agreed to maintain minimum releases of 400 cfs 

in the east channel for aquatic habitat enhancement and resident fish passage.

75 

Continuing this minimum release would benefit mussels and other aquatic organisms in 

the east channel. Based on results of York Haven Power’s mussel surveys, the east 

channel provides the best aquatic habitat for mussels in the project area.

The results of fish sampling by York Haven Power indicate that a diverse fish 

assemblage is present in this reach of the Susquehanna River. Based on a review of 

laboratory fish host studies (Strayer and Jirka, 1997; Nadeau et al., 2000; Wick, 2006; 

Spoo, 2008; NatureServe, 2010; PNHP, 2011b), it was determined the project area 

supports appropriate fish species to serve as fish hosts for mussels inhabiting this river 

 

75 The minimum releases are pursuant to the June 2010 Consent Order and 

Agreement between York Haven Power and Pennsylvania DEP.
191

reach. Given that many species of fishes act as fish host for eastern elliptio, it is unlikely 

that dams on the lower Susquehanna River, which are limiting passage of eels, are 

negatively affecting this mussel. 

Conowingo Project

The Conowingo Project has the potential to affect freshwater mussels downstream 

of the dam by causing flow and water level fluctuations associated with peaking 

operation, impeding the passage of fish species that serve as hosts for mussel species, and 

altering substrate composition downstream of the dam. Exelon proposes to implement 

measures to restore passage of American eel to tributaries upstream of the project by 

implementing a trap and truck program, which could benefit the eastern elliptio by 

expanding the range of this host species. The Nature Conservancy recommends that 

Exelon mitigate for loss of coarse sediments (such as sand, gravel, and cobble) within the 

project area between Conowingo dam and Chesapeake Bay, to enhance the habitat for 

living resources, including freshwater mussels. 

Our Analysis

The Nature Conservancy suggests that loss of coarse sediments below Conowingo

dam could be mitigated by extracting appropriate material from another location and 

placing it in appropriate areas that would not be subjected to erosive flow. Although this 

would likely increase the quantity of suitable habitat, it is unlikely that this would cause a 

notable increase in either mussel density or species richness. Mussel habitat below the 

dams is negatively affected by high discharge events, and increasing the amount of 

substrate appropriate for mussels would not eliminate the effects of high flow events.

Implementing Exelon’s proposal to transport American eel to and from tributaries 

upstream of the York Haven Project could provide some benefit to the eastern elliptio, 

but because many other species of fishes act as fish host for eastern elliptio this benefit is 

likely to be minimal. Given the diverse fishery that occurs upstream and downstream of 

Conowingo dam and the variety of fish that are passed upstream of Conowingo dam via 

the existing fish lifts, it is likely that there would continue to be sufficient fish host 

species to support a diverse freshwater mussel fauna.

We addressed the potential effects of flow and water level fluctuations associated 

with project operation and recommendations to modify operational constraints earlier in 

this section in our discussion under Downstream Flow Releases.

Invasive species

Limited numbers of zebra mussels have been detected downstream of Conowingo 

dam and York Haven dam, although no major infestations have been documented at the 

lower Susquehanna River projects. The projects do not directly influence the spread of 

the invasive zebra mussel and other exotic mollusks. Because of the concern over 

fouling by non-native bivalves at power plants, Exelon developed a set of mussel fouling 

prevention/control options that would provide a starting point in developing an effective 

zebra mussel control program. The measures include oxidizing biocides, non-oxidizing 
192

molluscicides, as well as a series of non-chemical options such as manual cleaning, use of 

pigs,76 high pressure water jets, strains, traps, filters and thermal treatment. Personnel

would be prepared to further evaluate and deploy any of these control methods if 

required.

3.3.2.3 Cumulative Effects

We previously identified water quantity, water quality, migratory fishes, and 

Chesapeake Bay habitat as resources that could be cumulatively affected by operation of 

the three projects, in combination with other projects and activities in the basin. While 

there would be some continuing effects from all the lower river hydroelectric projects 

related to flow regulation and effects on migratory species, the applicants for the York 

Haven, Muddy Run, and Conowingo projects are proposing a number of environmental 

enhancement measures that would offset some of the continuing effects. Staff is also 

recommending modifications to the applicant-proposed measures, and additional 

measures that would act to minimize cumulative effects. In addition to measures already 

implemented (such as minimum flows and fish passage facilities at the projects), new 

measures proposed and recommended include: (1) a nature-like fishway at the York 

Haven main dam, as well as measures to protect eel passage once they arrive in the 

project area; (2) investigations to ensure that migratory fish are successfully migrating 

past the Muddy Run Project; (3) increased minimum flows at Conowingo as 

recommended by staff; (4) improvements to the existing fish lifts at Conowingo as 

recommended by staff; and (5) provision of eel passage at Conowingo. All of these 

measures, in combination with fish passage improvements recently completed at the 

Holtwood Project, and the ongoing operation of the highly effective Safe Harbor Project 

fish lift, would result in an overall positive cumulative effect on migratory fish passage in 

the Susquehanna River. Flow regulation in the lower Susquehanna River would not be 

substantially changed under alternatives evaluated by the staff, although we evaluated an 

increase in minimum flows at Conowingo, which should enhance aquatic habitat 

downstream of the project into the Chesapeake Bay. Water quality has generally been 

protected in the lower river, including downstream of Conowingo dam with the addition 

of turbine venting and aeration that now maintains state DO standards nearly 100 percent 

of the time. Exelon is proposing to continue DO monitoring downstream of Conowingo 

and at Muddy Run in the future, and this would help ensure that state DO standards are 

continuing to be met. Overall, these measures would have a net beneficial cumulative 

effect on water quality, and aquatic habitat in the lower Susquehanna River and parts of 

the upper Chesapeake Bay that are influenced by project operation.

 

76 Pigs are devices that are placed inside pipes, to clean the inside of the pipe, 

often while the pipe remains in operation.
193

3.3.3 Terrestrial Resources

3.3.3.1 Affected Environment

Vegetation

The dominant upland cover classes in the vicinity of all three projects form a 

mosaic of agricultural, forest, and developed lands. Agricultural land ranges from 

intensely cropped cornfields and horticultural nurseries to less intensely used hayfields 

and pastures. Upland forest is typically found on land that has marginal utility for 

contemporary agricultural use, such as steep slopes and poorer quality soils.

Natural overstory vegetation within the York Haven project boundary includes red 

and silver maple, yellow birch, and black and northern red oak. Common shrub species 

include northern arrowwood, hornbeam, witch-hazel, and spicebush. The herbaceous 

layer is highly variable. Representative species include wild oats, false Solomon's-seal,

May-apple, and pipissewa. The major upland vegetation type within the project 

boundary is red oak-mixed hardwood forest, which is characterized by a well-developed 

canopy of mature red and black oak and red maple. Most of this community is located on 

the southern section of Three Mile Island.

Overstory vegetation within the Muddy Run and Conowingo project boundaries 

includes green ash, sycamore, black willow, and box elder along the reservoir shorelines; 

red and white oak, American beech, eastern hemlock, pignut hickory, sweet birch, black 

cherry, tulip polar, and sugar maple in forest interiors, with black locust and black walnut 

along forest edges. Evergreen communities are present in the project area, including 

eastern red cedar and Virginia, white, and sort-leaf pine. Representative shrub species 

include pawpaw, bladdernut, rosebay, eastern rebud, witch-hazel, northern arrowwood, 

maple-leaved viburnum, and spicebush. Herbaceous vegetation may include wild oats, 

may-apple, and striped wintergreen. The major upland vegetation type within both 

project boundaries is mixed mesophytic and species-rich hemlock-mesic hardwood forest 

(1,260 acres at Muddy Run and 856 acres at Conowingo). Lesser amounts of upland 

vegetation types include dry oak-mixed hardwood or red oak-mixed hardwood forest 

(265 acres at Muddy Run and 202 acres at Conowingo) and Virginia pine-mixed 

hardwood forest (38 acres at Muddy Run and 357 acres at Conowingo). In addition, 

maintained lawns comprise about 257 acres and agricultural croplands about 148 acres of

vegetation within the Muddy Run project boundary. About 800 acres, some of which is 

within the Muddy Run project boundary, is the Muddy Run WMA, which is managed to 

provide food and cover for wildlife. As noted in section 2.1.1, Existing Project 

Facilities, of the three projects, only the Muddy Run Project has primary transmission 

lines, two 4.25-mile-long, 230-kV transmission lines running from the powerhouse to the 

PBAPS North Substation along a 300-foot-wide corridor. The transmission lines pass 

from the powerhouse across about 0.5 mile of open water of the Susquehanna River. On 

the east side of the Susquehanna River, the transmission lines are surrounded by 
194

deciduous forest for about 1 mile after which the lines pass through agricultural fields 

(pasture and cropland) to the substation. 

Wetland and Riparian Habitat

York Haven Project

York Haven Power characterized wetland habitats occurring within the project 

boundary using FWS’ National Wetland Inventory digital mapping, which provides 

information on wetland habitats using remote sensing and aerial photo interpretation 

techniques (table 3-26). Extensive vegetated wetland communities are generally lacking 

in the project boundary. Wetlands within the project area are represented by riverine

(open-water), palustrine forested, and palustrine emergent wetland types.

Open-water areas are well represented in and adjacent to the project boundary, and 

Lake Frederic is an example of this open-water wetland habitat. Open-water habitats 

associated with Lake Frederic occupy about 2,363 acres. Lake Frederic contains many 

areas of SAV (primarily wild celery; Torocco et al., 2012) mostly found along island 

perimeters and areas of shallow water depth. 

The palustrine forested wetland habitats located within the project boundary are 

primarily forested silver maple floodplain areas. This forested wetland type typically 

occurs along larger rivers with a well-developed floodplain. Aside from the usually 

dominant silver maple, other trees include red maple, black willow, river birch, and 

American elm. Shrubs include poison ivy, spicebush, American elder, and northern 

arrow-wood. Common herbs include jewelweed, Japanese stiltgrass, and sensitive fern.

The largest areas of emergent wetlands occur on the southern section of Three 

Mile Island, within topographic depressions separate from the riparian zone associated 

with Lake Frederic. Several small emergent wetlands are mapped in the vicinity of 

where the main dam abuts Three Mile Island. Large areas of emergent vegetation are 

found bordering the western side of the access road leading to Three Mile Island. This 

area supports a variety of communities located within the floodplain of the Susquehanna 

River that are formed naturally by river flows and sedimentation. However, York Haven 

Power observed evidence of fill berms, old access roads, and other types of disturbance 

during various site visits associated with relicensing studies. 
195

Table 3-26. York Haven Project wetland types and acreages (Source: York Haven 

Power, 2012).

Class (FWS map 

code) Subclass Water Regime Total Acres Within Project Boundary

Unconsolidated 

bottom (R2UBH)

Not applicable Permanently flooded 2,240

Unconsolidated shore 

(R2USC)

Not applicable Seasonally flooded 111

Emergent (R2EM2H) Nonpersistent Permanently flooded 10

Unconsolidated 

bottom (R2UBHx)

Not applicable Permanently flooded 3

Forested (PFO1E) Broad-leaved 

deciduous

Seasonally 

flooded/saturated

31

Forested (PFO1C) Broad-leaved 

deciduous

Seasonally flooded 4

Scrub-shrub (PSS1) Broad-leaved 

deciduous

Seasonally flooded 6

Forested (PFO1A) Broad-leaved 

deciduous

Temporarily flooded 13

Unconsolidated 

bottom (PUBHx)

Not applicable Permanently flooded 1

Emergent (PEM1Cx) Persistent Seasonally flooded 17

Total wetland acreage 2,436

Three Mile Island has a mixture of floodplain forest located along the island 

boundaries, areas of emergent wetland, and large areas of open water bordered by 

palustrine forested and palustrine scrub-shrub wetland communities. York Haven Power 

notes that during overbank flooding this area holds a considerable amount of floodwater 

as the open water areas are inundated with water up to several feet in depth. The water 

regime in this system is typically seasonally flooded (i.e., surface water present for 

extended periods at certain times of the year). The vegetation associated with the 

wetlands on Three Mile Island consists of a mature canopy of various trees including red 

maple, silver maple, river birch, and sycamore. Common shrubs include species 

contained in the over-story layer, as well as black willow, elderberry, and silky dogwood. 

The herbaceous layer contains cattails, bur-reed, common rush, sedges, and smartweeds.
196

Muddy Run Project

The Muddy Run Project power reservoir and Recreation Lake provide open water 

habitat, and Exelon estimates that 84 percent of the reservoir shoreline is bordered by 

riparian woody vegetation, such as green ash, sycamore, black willow, and box elder.

The littoral zone around the power reservoir is about 240 acres, and the reservoir margin 

is free of emergent or submergent vegetation because of the magnitude and frequency of 

rapid water fluctuations (up to 50 feet on a weekly basis). Exelon identified six wetlands 

within the project boundary using FWS National Wetland Inventory mapping but did not 

quantify the area of each, although the descriptions suggest that they are relatively small. 

Each of these six wetlands was reviewed in the field to enable further characterization. 

Three wetlands are emergent wetlands (PEM) that appear to be supported by 

springs or seeps, and only one is adjacent to the power reservoir. Two of these emergent 

wetlands are dominated by sedges, rushes, and jewelweed. One of these two wetlands is 

within the transmission line right-of-way in a pasture. The third emergent wetland, 

located along a non-project natural gas pipeline, is dominated by the invasive common 

reed and reed canary grass; sedges, rushes, and jewelweed are also present along with 

cattails, goldenrod, and aster. This wetland has compacted soils related to the presence of 

the pipeline.

One wetland is a forested wetland (PFO1) along a small stream that drains into the 

power reservoir. It is dominated by red maple, spicebush, and skunk cabbage. A second

forested wetland with emergent components (PFO1/EM) is associated with a stream that 

ultimately flows into the reservoir. Dominant vegetation in this wetland includes 

sycamore and skunk cabbage.

The sixth wetland within the Muddy Run project boundary is an emergent/scrubshrub (PEM/SS1) wetland adjacent to the upper reaches of the recreation lake. Dominant 

vegetation in this wetland includes sedges, rushes, cattails, rice cutgrass, sweetflag, and 

blue vervain. 

Conowingo Project

Wetland habitat within the Conowingo Project boundary is governed by 

predominant substrate type and river hydrology. Conowingo Pond is generally operated 

at a maximum elevation of 109.2 feet, at which 8,605 acres of open-water habitat is 

provided. In the 7,000-foot-long reach from Holtwood dam to the downstream end of 

Hennery Island (see figure 2-2), the substrate is predominantly exposed bedrock. 

Downstream of Hennery Island, the bedrock channel bottom is covered with a thickening 

wedge of alluvial sediment that has been accumulating behind Conowingo dam since its 

construction in 1928. Downstream of Conowingo dam, a bedrock channel similar to that 

downstream of Holtwood dam influences the types of wetlands that are present. We 

discuss wetland habitat separately for the bedrock and alluvial channel types within the 

project boundary.
197

Bedrock reach--The bedrock reach at the upstream end of Conowingo Pond is 

characterized by riverbed emergent wetlands (REM). The wetland vegetation in the 

upper portion of the reach grows in cracks and crevasses on the protected downstream 

side of rocks. Pools in this upper reach are smaller (less than 100 square feet) and more 

isolated than further downstream where the pools are larger with more contiguous areas 

of open water (up to 10,000 square feet). Upstream vegetation is generally shorter and 

less abundant than downstream vegetation because the upstream, more-constricted reach 

is subjected to higher water levels and velocities than lower reaches. As the energy 

conditions diminish downstream, the vegetation becomes more prominent, growing on 

most available rock surfaces. Dominant vegetation within the lower elevation channel 

with longer periods of inundation includes water willow and purple loosestrife. Dense 

root mats with trapped sediment ultimately develop and may be stripped from the rock 

during high flow events. This lower elevation zone transitions to grasses, sedges, and 

rushes, the width of which is a function of slope. Along the shore margins of the river 

and islands, the riverbed emergent wetlands transition to a riparian wetland community 

dominated by woody vegetation such as black willow and red maple saplings (PSS1). 

The vegetation near the shoreline is composed of elements found growing on the riverbed 

as well as elements that encroach from the riparian forest located upgradient.

Similar to the riverbed emergent wetlands described in the previous paragraph, 

wetlands downstream of Conowingo dam consist largely of water willow that has taken 

root in fine sediment trapped within bedrock crevasses and interstices among boulders. 

However, emergent vegetation does not extend across the channel, as it did at places in 

the upper end of Conowingo Pond, but is restricted to river and island margins and 

tributary mouths. 

Alluvial reach--In the alluvial-dominated reach of Conowingo Pond, 

opportunities for the establishment of wetlands occur at sites of accumulating sediment, 

often at the mouths of tributaries. Wetland surveys of the alluvial reach conducted by 

Exelon in 2008 and 2010 identified 32 emergent wetlands (PEM) within the project 

boundary with varying degrees of open-water and scrub-shrub elements. The distribution 

of these wetlands reflects different geomorphic settings, water sources, and 

hydrodynamics. Although these wetlands are mapped, no indication of the area of each 

wetland or the total acreage of wetlands is provided. From the descriptions of the 

wetlands, they appear to be relatively small (i.e., each less than 1 acre). During typical, 

non-storm conditions, Exelon determined that the major driver of wetland properties of 9 

wetlands was primarily flows in the Susquehanna River (pond margin), 2 wetlands were 

strongly influenced by both the river and tributaries (pond/tributary), and 21 wetlands 

were influenced primarily by tributaries.

Common species occurring in the emergent wetlands include water willow, water 

pepper, broadleaf cattail, purple loosestrife, and Japanese stiltgrass. Although water 

willow was observed in most emergent wetlands, wetland vegetation generally comprised 

more than one dominant species (URS et al., 2012).
198

Invasive Plant Species

Invasive upland, wetland, and aquatic plants are known to occur at all three 

projects. The applicants did not propose and no entities requested that directed invasive 

plant surveys be conducted. However, incidental observations of invasive species were 

made during other studies at all three projects. York Haven Power identified invasive 

species that have the potential to occur at the York Haven Project, and this listing would 

also be applicable to the other two projects (table 3-27). 

Table 3-27. Invasive plants with potential to occur in the vicinity of the Susquehanna 

River Projects (Source: York Haven Power, 2012; Exelon, 2012a, 2012b, 

Staff).

Observed in Vicinity of Projectsa

Common name York Haven Muddy Run Conowingo

Aquatic

Eurasian watermilfoilX

Hydrilla X

Water chestnut

Brittle waternymph X

Terrestrial

Goutweed

Garlic mustard

Musk thistle

Canada thistle

Bull thistle

Jimsonweed

Goatsrue

Giant hogweed

Dame’s rocket

Purple loosestrife X

Star-of-Bethlehem

Wild parsnip

Beefsteak plant

Japanese knotweed X X
199

Observed in Vicinity of Projectsa

Common name York Haven Muddy Run Conowingo

Lesser celadine

Cheatgrass

Japanese stiltgrass X X X

Reed canary grass X

Shattercane

Common reed X X

Johnson grass

European barberry

Russian olive

Autumn olive X

Border privet

Common privet

Amur (bush)

honeysuckle

X

Morrow’s 

honeysuckle

Bell’s honeysuckle

Standish 

honeysuckle

Tartarian 

honeysuckle

Common buckthorn

Glossy buckthorn

Wineberry

Multiflora rose X

Sycamore maple

Tree-of-heaven X X

Empress tree

Siberian elm

Fiveleaf akebia
200

Observed in Vicinity of Projectsa

Common name York Haven Muddy Run Conowingo

Porcelain-berry

Oriental bittersweet

Japanese 

honeysuckle

Mile-a-minute vine X X

Kudzu

a Directed surveys for invasive plant species were not conducted at any of the three 

projects, but incidental observations were made during fieldwork associated with 

other studies.

At the York Haven Project, Japanese stiltgrass, Japanese knotweed, and mile-aminute vine were observed along old road edges and disturbed areas in the southern 

section of Three Mile Island. Within the floodplain of the Susquehanna River below the 

east channel dam and spillway, located in the southern section of Three Mile Island, large 

infestations of Japanese stiltgrass were observed in monotypic stands, where mile-aminute vine was also commonly observed. 

Invasive species, including mile-a-minute, tree-of-heaven, autumn olive, bush 

honeysuckle, and Japanese stiltgrass, were prevalent in areas along the western shore of 

the Muddy Run reservoir, but less so along the eastern shore. Invasive plants were most 

common along edge areas near the recreation park and in transmission line rights-of-way. 

Hydrilla and Eurasian water-milfoil were often the dominant species in SAV beds in the 

alluvial-dominated reach of Conowingo Pond. Downstream of Conowingo dam, 

Eurasian water-milfoil is the dominant SAV species. Hydrilla and purple loosestrife are 

also present in this reach. SAV is discussed in greater detail in section 3.3.2, Water 

Resources.

Sensitive Plants

York Haven Power and Exelon consulted with state natural resource agencies 

during pre-filing consultation and reviewed available literature to identify state-protected 

plant species and plant species that could be state-protected in the future with the 

potential to occur in the vicinity of each project. This process identified 31 such species 

that could occur near at least one of the projects (table 3-28), along with habitat 

preferences and whether or not the species was observed. 
201

Table 3-28. State protected plant species with potential to occur in the vicinity of the York Haven, Muddy Run, and/or 

Conowingo projects (Source: York Haven Power, 2012; Exelon, 2012a, 2012b).

Common Name 

(Scientific 

Name) State--Status

Potential 

Project 

Occurrencea Preferred Habitat Documented Occurrence

Bradley's 

spleenwort 

(Asplenium 

bradleyi)

PA -- Threatened C Acidic rock outcrops and 

barrens, within crevices and 

ledges, and on cliff faces

Historically occurred in the 

vicinity of the Conowingo 

project area. Although the 

general habitat for a plant may 

be present in the project area, 

Bradley’s spleenworts were 

not observed in the project 

area. 

Aster-like 

boltonia

(Boltonia 

asteroides)

PA, MD --

Endangered

YH, C Open canopy wetlands with 

sandy to loamy acidic soils; 

gravel shores; sandy, wet 

thickets, alluvial meadows and 

marshes, and openings in 

forested floodplains

Reportedly found in the 

riverside outcrop community 

of the Holtwood dam spillway 

area; however, none were 

observed in the project area. 

Reflexed 

flatsedge 

(Cyperus 

refractus)

PA --

Endangered

MR, C Found in dry woods with an 

open canopy and sandy soils; 

also associated with fields, 

barrens

Historically occurred in the 

vicinity of the Conowingo 

Project area. Although the 

general habitat for a plant may 

be present in the project area, 

reflexed flatsedges were not 

observed in the project areas. 
202

Common Name 

(Scientific 

Name) State--Status

Potential 

Project 

Occurrencea Preferred Habitat Documented Occurrence

Flat-stemmed 

spike-rush 

(Eleocharis 

compressa)

PA, MD --

Endangered

YH, C Found in wet depressions in 

woodlands and limestone 

glades, wet prairies, roadside 

ditches; and other wet seeps in 

calcareous grasslands, fens, 

sandy ground, stream banks and 

waste places

Reportedly found between 

Conowingo dam and the 

mouth of Octoraro Creek (in or 

near Susquehanna Floodplain 

Protection Area). However, 

this species was not observed 

within the project boundary. 

Ellisia (Ellisia 

nyctelea)

PA -- Threatened YH Found in damp, shady stream 

banks with rich alluvial soils 

and sometimes on disturbed 

ground

Potentially could occur within 

0.5 mile of the York Haven 

Project area. Although the 

general habitat for the plant 

may be present in the project 

area, ellisia was not observed 

in the project area.

Harbinger-ofspring (Erigenia 

bulbosa)

PA -- Threatened C Found in rich, mixed hardwood 

forests located in lowlands, 

coastal plains, and mountain 

valleys

Historically occurred in the 

vicinity of the Conowingo 

Project area. Although the 

general habitat for the plant 

may be present in the project 

area, harbinger-of-spring was 

not observed in the project 

area.
203

Common Name 

(Scientific 

Name) State--Status

Potential 

Project 

Occurrencea Preferred Habitat Documented Occurrence

Bicknell’s hoary 

rockrose 

(Helianthemum 

bicknellii)

PA, MD --

Endangered

C Found in dry, open areas with 

abundant sun and generally thin 

soil; around exposed banks, dry 

rocky slopes and outcrops, open 

woods, serpentine barrens and 

open forests

Historically occurred in the 

vicinity of the Conowingo 

Project area. Although the 

general habitat for a plant may 

be present in the project area, 

Bicknell’s hoary rockroses 

were not observed in the 

project area.

American holly 

(Ilex opaca)

PA -- Threatened C Typically found in shallow, 

well-drained, sandy soil; also 

found in coastal dunes and 

deciduous woodlands; and 

within moist alluvial woods and 

along wooded slopes

Historically occurred in the 

vicinity of the Conowingo 

Project area. Although the 

general habitat for a plant may 

be present in the project area, 

American hollies were not 

observed in the project area.

Common 

hemicarpa 

(Lipocarpha 

micrantha)

PA --

Endangered

C Prefers moist, sandy soil; found 

along sparsely vegetated ponds, 

streams, and sandy beaches 

without large water level 

fluctuations or strong currents

Historically occurred in the 

vicinity of the Conowingo 

Project area. Although the 

general habitat for a plant may 

be present in the project area, 

common hemicarpas were not 

observed in the project area.
204

Common Name 

(Scientific 

Name) State--Status

Potential 

Project 

Occurrencea Preferred Habitat Documented Occurrence

False loosestrife 

seedbox 

(Ludwigia 

polycarpa)

PA --

Endangered

C Found on level terrain in open 

canopy areas, including former 

oxbows, river channels in 

floodplain swamps, marshes, 

and wet prairies, and on the 

shores of ponds and other wet 

places

Historically occurred in the 

vicinity of the Conowingo 

Project area. Although the 

general habitat for a plant may 

be present in the project area, 

false loosestrife seedbox were 

not observed in the project 

area.

Umbrella 

magnolia 

(Magnolia 

tripetala)

PA -- Threatened MR, C Prefers upland areas with fine to 

medium textured soils that are 

neutral to slightly acidic; found 

in rich woods and ravines, near 

mountain streams and other wet 

areas, and in mesic shaded 

coves

Historically occurred in the 

vicinity of both Muddy Run 

and Conowingo Project areas. 

Although the general habitat 

for a plant may be present in 

the project areas, umbrella 

magnolias were not observed 

in the project area.

Three-flowered 

melicgrass 

(Melica nitens)

PA -- Threatened C Prefers a partly open canopy 

and calcareous or sandy loam 

soil; found in open dry woods; 

rocky grasslands; streambanks; 

and dry to mesic prairies

Historically occurred in the 

vicinity of the Conowingo 

Project area. Although the 

general habitat for a plant may 

be present in the project area, 

three-flowered melicgrasses 

were not observed in the 

project area.
205

Common Name 

(Scientific 

Name) State--Status

Potential 

Project 

Occurrencea Preferred Habitat Documented Occurrence

Sticky 

goldenrod 

(Solidago 

simplex ssp. 

randii var. 

racemosa)

PA --

Endangered

C Typically found in 

boulder/cobble river bars

Documented community in a 

riverside outcrop below 

Holtwood Dam, included areas 

downstream of the Norman 

Wood Bridge within the 

Conowingo Project. However, 

this species was not identified 

within the project boundary.

Slender 

goldenrod 

(Solidago 

erecta)

PA --

Endangered and 

MD --

Threatened

C Found in both loamy and sandy 

soils; typically in open woods 

and fields

Historically occurred in the 

vicinity of the Conowingo 

Project area. Although the 

general habitat for a plant may 

be present in the project area, 

slender goldenrods were not 

observed in the project area. 

Tawny 

ironweed 

(Vernonia 

glauca)

PA --

Endangered

C Typically found in sandy to clay 

soils that can be acidic, neutral, 

or basic; usually in upland 

woods, dry fields and clearings, 

and rich woods

Historically occurred in the 

vicinity of the Conowingo 

Project area. Although the 

general habitat for a plant may 

be present in the project area, 

tawny ironweeds were not 

observed in the project area. 
206

Common Name 

(Scientific 

Name) State--Status

Potential 

Project 

Occurrencea Preferred Habitat Documented Occurrence

Appalachian 

gametophyte 

fern (Vittaria 

appalachiana)

PA -- Threatened C Found on noncalcareous rocks, 

in dark moist cavities, and 

occasionally as an epiphyte on 

tree bases

Historically occurred in the 

vicinity of the Conowingo 

Project area. Although the 

general habitat for a plant may 

be present in the project area, 

Appalachian gametophyte 

ferns were not observed in the 

project area.

Davis' sedge 

(Carex davisii)

MD --

Endangered

C Found in both upland and 

floodplain woodlands where the 

canopy is somewhat open; also 

inhabits deciduous forested 

floodplains and moist limestone 

woodlands, rocky shores, 

abandoned fields and wet 

meadows, and unpaved trails

Documented scattered 

populations found in forested 

floodplains, rocky shores, and 

moist woods in or near the 

Northern Susquehanna Canal 

Protection Area north of the 

mouth of Deer Creek. 

However, this species was not 

observed within the project 

boundary.

Hitchcock's 

sedge (Carex 

hitchcockiana)

MD --

Endangered

C Found under a mostly closed 

canopy of rich mesic woods, in 

rock soils along unstable slopes, 

and in calcium-rich loams on 

slopes near streams

Documented occurrences in or 

near the Susquehanna Slopes 

Protection Area along the 

wooded shoreline slopes north 

of Conowingo Creek. 

However, this species was not 

observed within the project 

boundary.
207

Common Name 

(Scientific 

Name) State--Status

Potential 

Project 

Occurrencea Preferred Habitat Documented Occurrence

Glade fern 

(Diplazium 

pycnocarpon)

MD --

Threatened

C Prefers neutral to slightly 

alkaline soils and found in 

moist open woods and slopes, 

moist meadows, swamps, and 

forested ravines

Documented scattered 

populations found in forested 

floodplains, rocky shores, and 

moist woods in or near the 

Northern Susquehanna Canal 

Protection Area north of the 

mouth of Deer Creek. 

However, this species was not 

observed within the project 

boundary.

Sweet-scented 

Indian plantain 

(Hasteola 

suaveolens)

MD --

Endangered

C Prefers an open Canopy; found 

in alluvial soils on high-energy 

floodplains and stream banks 

but can also be found within 

open woodlands and along the 

edges of thickets

Documented scattered 

populations were found in 

forested floodplains, rocky 

shores, and moist woods in or 

near the Northern Susquehanna 

Canal Protection Area north of 

the mouth of Deer Creek. 

However, this species was not 

observed within the project 

boundary.
208

Common Name 

(Scientific 

Name) State--Status

Potential 

Project 

Occurrencea Preferred Habitat Documented Occurrence

Goldenseal 

(Hydrastis 

canadensis)

MD --

Threatened

C Found in moist, well-drained 

acidic sandy loam soil that 

contains abundant organic 

matter; possibly found within 

mixed hardwood forests 

(Henson, 2001), rich moist 

woodlands, and along wooded 

streams

Documented population in the 

wooded bluffs in or near Glen 

Cove Marina and in or near the 

Susquehanna Slopes Protection 

Area along the wooded 

shoreline between U.S. Route 

1 and Conowingo Creek boat 

landing and north of 

Conowingo Creek. However, 

this species was not observed 

within the project boundary. 

American 

gromwell 

(Lithospermum 

latifolium)

PA -- and MD --

Endangered

C Prefers a partly closed canopy 

with light to medium shade; 

found in loamy soil that 

contains abundant organic 

matter in rich deciduous woods, 

wooded slopes, and along 

shaded riverbanks

Documented along the 

shoreline, mostly in rich moist 

woods, between U.S. Route 1 

and Conowingo Creek boat 

landing (in or near the 

Susquehanna Slopes Protection 

Area). However, this species 

was not observed within the 

project boundary.
209

Common Name 

(Scientific 

Name) State--Status

Potential 

Project 

Occurrencea Preferred Habitat Documented Occurrence

Tall dock 

(Rumex 

altissimus)

MD --

Endangered

C Prefers full to part sun and rich 

fertile soil and may tolerate 

gravel and/or clay; found in wet 

depressions, stream margins and 

low areas along ponds, lakes 

and riverbanks

Documented on the north and 

south sides of the Octoraro 

Creek mouth (in or near the 

Susquehanna Floodplain 

Protection Area). However, 

this species was not observed 

within the project boundary.

Veined skullcap 

(Scutellaria 

nervosa)

MD --

Endangered

C Found in wet to mesic 

deciduous woodlands, near 

wetland edges, and in wet 

depressional floodplain forests

Documented along the 

shoreline, mostly in rich moist 

woods, between U.S. Route 1 

and Conowingo Creek boat 

landing (in or near the 

Susquehanna Slopes Protection 

Area). However, this species 

was not observed within the 

project boundary.

Virginia mallow 

(Sida 

hermaphrodita)

PA -- and MD --

Endangered

C Prefers mostly open canopy; 

found in sandy or rocky alluvial

soil and on stream and 

riverbanks

Documented in the WSSC of 

Wildcat Ravine. However, 

this species was not observed 

within the project boundary.
210

Common Name 

(Scientific 

Name) State--Status

Potential 

Project 

Occurrencea Preferred Habitat Documented Occurrence

Star-flowered 

false Solomon's 

seal (Smilacina 

stellata)

MD --

Endangered

C Prefers wetlands and shallow 

soils; also found on rocky, welldrained side hills, coastal plains, 

thickets, and open forests 

adjacent to streams

Scattered populations observed 

in the forested floodplains, 

rocky shores, and moist woods 

in or near the Northern 

Susquehanna Canal Protection 

Area north of the mouth of 

Deer Creek. However, this 

species was not observed 

within the project boundary.

Swamp oats 

(Sphenopholis 

pensylvanica)

MD --

Threatened

C Requires full sun and grows in 

wet meadows and woods, 

swamps, and stream sides

Documented along the 

shoreline in swamp habitat 

between U.S. Route 1 and 

Conowingo Creek boat landing 

(in or near the Susquehanna 

Slopes Protection Area). 

However, this species was not 

observed within the project 

boundary.
211

Common Name 

(Scientific 

Name) State--Status

Potential 

Project 

Occurrencea Preferred Habitat Documented Occurrence

Valerian 

(Valeriana 

pauciflora)

MD --

Endangered

C Found in the rich loamy soils 

associated with forested 

floodplains, mesic forests, and 

along moist wooded stream 

banks

Documented on the floodplain 

downstream of Octoraro Creek 

(in or near the Susquehanna 

Floodplain Protection Area) 

and in forested floodplain, 

rocky shore, and moist woods 

habitat in or near the Northern 

Susquehanna Canal Protection 

Area north of the mouth of 

Deer Creek. However, this 

species was not observed 

within the project boundary.

Eastern gamagrass 

(Tripsacum 

dactyloides)

PA --

Undetermined

MR Found in wetter areas associated 

with swales, thickets, woodland 

borders, abandoned fields, wet 

shores, roadsides, and limestone 

glades and prefers an open 

canopy

Historically, may have occurred 

in the vicinity of Muddy Run 

Project area. Although the 

general habitat for a plant may 

be present in the project area, 

this species was not observed in 

the project area.

Cranefly orchid 

(Tipularia 

discolor)

PA -- Rare MR An upland plant species found 

in rich well-drained soils within 

in mixed hardwood forests. 

Known to occur within the 

boundaries of the Ferncliff 

Wildlife and Wildflower 

Preserve

Historically occurred in the 

vicinity of Muddy Run Project 

area. Although the general 

habitat for a plant may be 

present in the project area, 

cranefly orchids were not 

observed in the project area.
212

Common Name 

(Scientific 

Name) State--Status

Potential 

Project 

Occurrencea Preferred Habitat Documented Occurrence

Netted chainfern 

(Woodwardia 

areolata)

PA -- Non-listed MR Typically found in wetlands 

with moist, acidic soils; found 

in acidic bogs, woodland 

swamps, thickets, on seeps, 

siliceous cliffs and ledges, and 

near still water

Historically occurred in the 

vicinity of Muddy Run Project 

area. Although the general 

habitat for a plant may be 

present in the project area, this 

species was not observed in the 

project area. a YH= York Haven, MR= Muddy Run, C= Conowingo
213

Wildlife

Open-water, wetland, riparian, and upland habitat within the three project 

boundaries supports a variety of wildlife. Wildlife occupying each habitat type at all 

three projects is expected to be similar.

Reptiles and Amphibians 

Representative reptile and amphibians that are typically found in open-water, 

riparian, and wetland habitats such as Lake Frederic, tributaries, and the Susquehanna 

River include snapping turtle, red-eared slider, common musk turtle, map turtle, northern 

water snake, northern spring peeper, bullfrog, northern leopard frog, pickerel frog, and 

green frog. These species use aquatic habitats for foraging, resting, protection, 

reproduction, and hibernation. Representative reptiles and amphibians typically found in 

upland and riparian habitat in the vicinity of the projects include: eastern garter snake, 

northern ribbon snake, American toad, gray tree frog, wood frog, spotted salamander, and 

northern red-backed salamander. 

Birds

The Susquehanna River and associated water resources and bottomland areas in 

the projects’ vicinity are used by migratory waterfowl and neotropical passerines. 

Representative avian species typically found in wetland habitats and along the shoreline 

include the great blue heron, cattle egret, great egret, yellow-crowned night heron, redwinged blackbird, swamp sparrow, song sparrow, mallard, wood duck, American black 

duck, common merganser, and Canada goose. Species such as the ducks may nest within 

vegetated shallows and bottomlands and forage in open water.

Upland and riparian habitat associated with the project areas provide breeding, 

migratory stopover, and wintering habitat for a high diversity of bird species including 

neotropical songbirds and resident species. Species such as the black capped chickadee, 

house wren, song sparrow, white-breasted nuthatch, brown creeper, and an assortment of 

woodpeckers occur along the wooded shorelines of the project areas. Birds that inhabit 

non-forested areas within the project areas include American robin, eastern bluebird, 

mourning dove, and rock dove. A high diversity of migrating warblers also use the 

upland habitats, and several species of birds of prey are known or suspected to use the 

project areas. Some of these birds of prey include: bald eagle, osprey, Cooper’s hawk, 

red-tailed hawk, American kestrel, great horned owl, and barred owl. These species use 

many different habitat types throughout the year including woodland, scrub-shrub or 

early successional areas, and wetland, and open-water areas.

Mammals

White-tailed deer is the most common big game species in the project vicinities, 

commonly occurring along forest edges characterized by brushy and woody vegetation, 

swamp borders, and areas interspersed with fields and woodland openings. Raccoon are 
214

also common, especially along the riparian corridor associated with the Susquehanna 

River. Other mammals present in the project vicinities include: urban and suburban 

species such as striped skunk and opossum; furbearers such as red and gray fox and longtailed weasel; small game species such as gray and red squirrel and eastern cottontail; 

rodents such as white-footed, deer and house mouse; and little and big brown bat. 

Sensitive Wildlife Species

York Haven Power and Exelon consulted with state natural resource agencies 

during pre-filing consultation and reviewed available literature to identify state-protected 

wildlife species with the potential to occur in the vicinity of the Susquehanna River 

Projects, and identified 13 state-listed species that either do or could occur in the vicinity 

of at least one of the three projects. Several of these species, including eastern redbelly 

turtle (York Haven), bald eagle (Muddy Run and Conowingo), osprey (Muddy Run and 

Conowingo), black-crowned night-heron (Conowingo), and rough green snake (Muddy 

Run), were studied during the licensing proceedings. In addition, FWS has proposed to 

list the northern long-eared bat for protection under the ESA. Table 3-29 shows the 13 

state-protected species and the one species proposed for federal listing, along with habitat 

preferences and whether or not the species were observed in the vicinity of the project. 

The bog turtle is both state and federally listed and is discussed in section 3.3.4, 

Threatened and Endangered Species. Existing and potential future project operation 

could affect the bald eagle, osprey, northern map turtle, and northern long-eared bat, and 

we provide more detailed information regarding these species in the following 

subsections.

Bald eagle

The bald eagle is listed as threatened in Pennsylvania and is federally protected 

under the Bald and Golden Eagle Protection Act of 1940, as amended. Bald eagles are 

currently found in every state except Hawaii. Eagles prefer undisturbed areas near large 

lakes and reservoirs, marshes and swamps, and stretches along rivers where they can find 

open water and their primary food, fish. Nests are primarily constructed in dominant 

mature trees (often pine, sycamore, red oak, and red maple), or cliffs near water but 

occasionally are also built on man-made structures. Egg laying and incubation by local 

populations occur between January and April with fledging occurring as early as midJune and as late as the end of July. Nesting eagles are particularly sensitive to human 

intrusions and such activities can compel eagles to abandon a nest. 

At the York Haven Project, one bald eagle nest was reported to occur at the 

southern end of Three Mile Island based on York Haven Power’s review of available 

information (no site specific surveys for bald eagles were proposed by the applicant or 

recommended by other entities). Lake Frederic provides large populations of warmwater fish species that form a reliable source of live prey for foraging bald eagles. One 

active nest and a communal roosting site have been documented within the Muddy Run 
215

Project boundary and a reported nest was found on a Conowingo Pond island traversed 

by the Muddy Run transmission line corridor. At the Conowingo Project, bald eagle 

surveys conducted by Exelon documented 11 pairs of breeding bald eagles, 18 communal 

bald eagle roosts, and many foraging bald eagles along Conowingo Pond and 

downstream of Conowingo dam. Exelon observed up to 153 bald eagles per week during 

bald eagle surveys of known roosting areas in 2010 and 2011 (Center for Conservation 

Biology et al., 2012). Bald eagles occur in the vicinity of the three projects year round, 

but are less common during the winter.

Osprey

The osprey is listed as threatened in Pennsylvania and is federally protected under 

the Migratory Bird Treaty Act of 1918. Ospreys are found along seacoasts and major 

waterways on every continent except Antarctica. Fish are the primary prey for osprey, 

although they also feed on small waterfowl, mammals, and carrion. Ospreys typically 

inhabit salt marshes, large inland rivers, lakes, ponds, and wetlands bordered by mature 

trees. Nests are usually built near water in large, often dead, trees but nests have also 

been found on channel markers, telephone poles, chimneys, and manmade platforms built 

specifically for their use. Preferred foraging habitat of local osprey populations was 

reported to be shallow water with low turbidity. Osprey pairs typically return to 

Pennsylvania in late March to early April to nest and depart by the end of September. 

At the York Haven Project no directed osprey surveys were proposed or requested, 

but an osprey nest is located on the York Haven powerhouse and field staff performing 

other studies frequently observed osprey flying in the vicinity of Lake Frederic. Exelon 

conducted osprey nest surveys at the Muddy Run and Conowingo projects in 2010 and 

2011. During both years an active osprey nest was documented along the shore of 

Muddy Run reservoir. Eleven osprey nests were documented in the Conowingo project 

area in 2010, and a twelfth in 2011 (8 were in Pennsylvania and 4 in Maryland). All of 

the nests observed in 2010 were active in 2011, with the exception of two nests in 

Pennsylvania. Osprey activity was frequently observed at the Muddy Run transmission 

line crossing of the river and entailed ospreys using the transmission towers for perching.

Northern map turtle

The northern map turtle is listed by Maryland as an endangered species. Map 

turtles are found in deep, slow-moving large rivers and lakes with ample locations for 

basking. Muddy bottom with aquatic vegetation are preferred and vegetation comprises 

the majority of the map turtle diet. Mollusks and crayfish are also occasionally 

consumed. Eggs are laid from April to mid-July in areas with open canopies most often 

on sunny days after rain events. Turtles were found to make almost immediate use of 

newly-opened gaps (i.e., tree-falls) in the forest canopy. Hatching occurs from midAugust through September.
216

According to Towson University studies, a reproductively active population 

occurs both upstream and downstream of Conowingo dam, although most turtles are 

concentrated in a 1.2-mile-long river reach downstream of the dam in the vicinity of Port 

Deposit and Susquehanna State Park in Maryland (Seigel et al., 2014). Nesting occurs in 

relatively open areas on both in-river islands, along the banks of Octoraro and Deer 

creeks, and in the town of Port Deposit. Most nesting areas are heavily disturbed by 

recreational visitors, raccoons, foxes, and feral dogs. Towson University biologists 

observed basking map turtles from late April through mid-November, with the most 

intensive activity in September. Basking occurs predominantly on rocks and large woody 

debris, but can also occur on man-made structures such as bulkhead footings and riprap. 

Basking is an essential activity for most aquatic turtles, serving to raise body 

temperatures so that physiological processes such as digestion and egg development are 

maximized. Reptiles that are precluded from basking may suffer reduced reproductive 

output and growth rates (Seigel et al., 2014). 

Northern long-eared bat

The northern long-eared bat (Myotis septentrionalis) is not currently federally 

listed, but is proposed to be listed as endangered, with a final rule expected in October 

2014. FWS published a proposal to list the northern long-eared bat as endangered in the 

Federal Register on October 2, 2013. In Pennsylvania, it is a candidate for listing as a 

rare species, but more information is needed before adequate management decisions can 

be made (PNHP, 2014). The northern long-eared bat’s range extends from Maine to 

North Carolina along the Atlantic coast, including the Susquehanna River in the vicinity 

of the three projects. The northern long-eared bat historically occurred in Lancaster 

County based on pre-1980 data, and currently occurs in York and Dauphin counties based 

on data from 1980 to the present (PNHP, 2014). During winter hibernation, the northern 

long-eared bat dwells in underground caves and similar sites. Suitable roosting caves 

need large open space with cracks and crevices, cool temperature (32 to 48°F), high 

humidity, and low air movement. Spring migration to new habitat happens from midMarch to mid-May. During summer migration, roosting occurs underneath bark, cavities 

or hollows of trees or snags (typically greater than 3 inches diameter at breast height 

[dbh]), although occasional roosting in barns and sheds have occurred. Preferred roosting 

trees such as shagbark hickory and oaks usually display exfoliating bark, hollows, 

cavities, and crevices. The northern long-eared bat forages in lowland woods, along 

forest edges and in corridors, feeding on insects. Fall migration and the return to

wintering habitat occur between mid-August and mid-October (FWS, 2014a). Neither 

York Haven Power nor Exelon conducted surveys for the northern long-eared bat and no 

entity requested that surveys be conducted.
217

Table 3-29. State-protected wildlife species with potential to occur in the vicinity of the York Haven, Muddy Run, and/or 

Conowingo projects (Source: York Haven Power, 2012; Exelon, 2012a, 2012b).

Common Name State Status Potential Project 

Occurrencea Preferred Habitat Documented Occurrence

Bald eagle PA --

Threatened

YH, MR,b Cc Undisturbed areas near large 

lakes and reservoirs, marshes 

and swamps, or stretches along 

rivers with open water and 

access to fish; nearby tall trees 

for roosting and nesting. Can 

be found in the projects’ 

vicinities year round.

Please see previous detailed 

discussion.

Osprey PA --

Threatened

YH, MR,d Ce Along seacoast and major 

waterways with access to fish; 

nests usually built near water in 

large trees, but also use channel 

markers, telephone poles, 

chimneys, and platforms built 

specifically for their use. 

Found near projects in spring 

and summer.

Please see previous detailed 

discussion.

Peregrine falcon PA --

Endangered

YH Nest and roost on high 

prominences, building, cliffs, 

and other open spaces with 

expansive views.

Reportedly a pair returned to 

nest at the Three Mile Island 

Unit 1 Reactor Building in 

2010; however, none 

observed during projectrelated field work, and there 

is no suitable nesting habitat 

in the project area, other than 
218

Common Name State Status Potential Project 

Occurrencea Preferred Habitat Documented Occurrence

at Three Mile Island.

American 

bittern

PA --

Endangered

YH Found in expansive wetland 

habitats and wetland borders 

along lakes, ponds, rivers and 

streams; breed in large 

wetlands, especially those with 

dense stands of cattails, 

bulrushes, grasses, and sedges,

and pockets of open water.

Not observed in the vicinity 

of the project and expansive 

wetland habitats are lacking.

Yellowcrowned nightheron

PA --

Endangered

YH Typically feed along small, 

shallow streams and nest in 

brush or trees, usually 

sycamores, found on islands or 

along streams.

The project area below the 

east channel dam and along 

the southeastern side of 

Three Mile Island provides 

riparian forest and scrubshrub wetlands that could 

provide suitable habitat, but 

none observed during 2010 

and 2011 field seasons.

Black-crowned 

night-heron

PA --

Endangered

YH, Cf Found primarily near rivers and 

creeks, but also margins of 

lakes and reservoirs and 

wetlands; often colonial nest on 

forested islands or along 

wooded streams.

Reported to occur in the 

vicinity of York Haven but 

none were observed during 

2010 and 2011 field seasons. 

Three to six black-crowned 

night-herons were regularly 

observed near the 

Conowingo dam tailrace and 

spillway and on Rowland 
219

Common Name State Status Potential Project 

Occurrencea Preferred Habitat Documented Occurrence

Island during 2010 and 2011, 

foraging below the dam and 

roosting in trees on the 

island. No nests observed, 

but potential nesting habitat 

is present.

Common tern PA --

Endangered

YH Typically seen flying over 

lakes, slow-moving rivers, or 

occasionally marshes, or 

perched on beaches, sand pits, 

mudflats, or on structures such 

as buoys or piers. Nesting 

habitat restricted to sandy 

shorelines and barren islands of 

large lakes; currently not 

known to nest in PA.

No common terns were 

observed during 2010 or 

2011 field seasons.

Black tern PA --

Endangered

YH When not nesting, found along 

the coast; move inland to nest 

on prairies or extensive marsh 

complexes that are half open 

water and half emergent 

vegetation. Northwest PA is 

the only location in state where 

nesting occurs.

Expansive wetland 

complexes do not occur in 

the vicinity of the project. 

No black terns observed 

during 2010 or 2011 field 

survey seasons.

Yellow-bellied 

flycatcher

PA --

Endangered

YH In shady coniferous forests and 

forested wetlands at higher 

elevations; nesting occurs in 

Habitat generally lacking in 

the project boundary. No 

yellow-bellied flycatchers 
220

Common Name State Status Potential Project 

Occurrencea Preferred Habitat Documented Occurrence

remote areas. were observed during 2010 

and 2011 field survey 

seasons.

Hellbender 

salamander

MD --

Endangered

C Fast-moving, mid-sized 

streams/channels with good 

water quality and gravel or sand 

substrate and abundant large 

structures for hiding; breed in 

late summer.

Only historic (confirmed and 

unconfirmed) records of 

occurrence in Cecil County 

and unconfirmed historic 

records for Harford County, 

all in the Susquehanna River 

and tributaries (Stranko et 

al., 2010).

Northern map 

turtle

MD --

Endangered

C Deep slow-moving large rivers 

and lakes with ample locations 

for basking; muddy bottoms 

with aquatic vegetation are 

preferred.

Please see previous detailed 

discussion.

Eastern redbelly 

turtle

PA --

Threatened

YHg Water depths ranging from 6.5 

to 12.0 feet deep with an 

abundance of aquatic 

vegetation, reduced current 

velocities, soft substrates, and 

rocks and logs for basking. 

They nest on sandy areas along 

shorelines.

York Haven Power 

conducted targeted surveys 

during 2011 for eastern 

redbelly turtles in Lake 

Frederic using established 

protocols and none were 

found.

Rough green 

snake

PA --

Endangered

YH, MR,h C Moist areas such as wet 

meadows and the borders of 

lakes, marshes, and woodland 

Documented in PA only 

from Greene and southern 

Chester counties although 
221

Common Name State Status Potential Project 

Occurrencea Preferred Habitat Documented Occurrence

streams; frequently found in 

woody vegetation growing 

along or overhanging water.

recent evidence places them 

in Lancaster County near the 

Muddy Run and Conowingo 

projects. Suitable habitat is 

present in the vicinity of the 

projects. No rough green 

snakes were observed during 

targeted surveys (at Muddy 

Run) or other field studies at 

all three projects.

Northern longeared batPA -- Candidate 

for rare species 

designation

YH, MR, C During the summer, roosting 

occurs underneath bark, 

cavities, or hollows of trees or 

snags; in winter, they hibernate 

in caves or similar sites

Please see previous detailed 

discussion

a YH= York Haven, MR= Muddy Run, C= Conowingo

b Study 3.8: Study to identify habitat use areas for bald eagle, Muddy Run Pumped Storage Project. c Study 3.23: Study to identify habitat use areas for bald eagle, Conowingo Hydroelectric Project.

d Study 3.15: Osprey nesting survey, Muddy Run Pumped Storage Project. e Study 3.30: Osprey nesting survey, Conowingo Hydroelectric Project.

f Study 3.31: Black-crowned night-heron nesting survey, Conowingo Hydroelectric Project.

g Eastern redbelly turtle phase II presence/absence and nesting surveys for the York Haven Hydroelectric Project.

h Study 3.9B: Study to identify potential habitat and presence/inferred absence of rough green snake, Muddy Run 

Pumped Storage Project.
222

3.3.3.2 Environmental Effects

Effects of project operation and water level fluctuations on riparian, littoral, 

and wetland habitat 

For all three projects, project operation, including water level fluctuations, could

affect riparian, littoral, and wetland habitat. Reservoir fluctuations and changes in 

downstream flows could affect the distribution, species composition, and health of 

wetland and riparian habitat. Wetland and riparian habitats are important for functions 

such as water quality, habitat for fish and wildlife, regulating flooding, and stream 

recharge.

According to the terms of the Settlement Agreement, York Haven Power proposes 

to maintain the overall project minimum flow requirements downstream of the project, 

but it would modify project flow releases to redistribute minimum flow releases among 

the various project flow release structures (east channel spillway, east channel fishway,

nature-like fishway, main dam, and powerhouse).

Exelon does not propose any changes to the existing project operation at Muddy 

Run or Conowingo. There are no recommended measures specifically relating to 

wetlands, riparian, or littoral habitat at either project; however, The Nature Conservancy 

recommended, and Interior endorsed, an alternate flow regime for flows below 

Conowingo dam, referred to as the TNC Flow Regime. The TNC Flow Regime is 

described in greater detail in section 3.3.2.2, Water Resources, Environmental Effects, but 

in general it would stabilize flows below the dam, particularly from March through June. 

Our Analysis

Under existing and proposed operation, extensive vegetated wetland communities 

are and would be generally lacking in the York Haven Project boundary. Three Mile 

Island contains the largest of the emergent marsh wetlands as well as forested floodplain 

wetlands. Existing and proposed project operations would allow for 1.1 feet of draw 

down from the impoundment for dam maintenance activities. Because proposed 

operation would not change the reservoir levels or the overall minimum flows 

downstream of the York Haven Project, it is not expected that wetland, riparian, or 

wildlife habitat conditions would change.

The Muddy Run Project operates as a pumped storage facility by moving water 

from the upper reservoir to the lower reservoir (Conowingo Pond) via gravity to generate 

power. Water levels in the upper reservoir can fluctuate up to 50 feet within a week. 

With these large fluctuations, shoreline habitat would vary between dry and flooded 

periods. As a result, the upper reservoir margins are generally free of emergent or 

submerged vegetation. Exelon plans to implement an SMP that includes erosion control 

measures (see further discussion in section 3.3.5, Recreation and Land Use Resources) at 
223

the Muddy Run upper reservoir to minimize erosion. Of the six wetlands identified in the 

project boundary, only one (which is adjacent to the upper reservoir) would appear to be 

affected by project operation; however, even this wetland has its own source of 

hydrology. Because the Muddy Run Project would be operated as it has in the past, the 

existing wetland and riparian habitat would remain similar to their present condition and 

wildlife habitat would not be affected. Fluctuations of the lower reservoir, Conowingo 

pond, are discussed below for the Conowingo Project. 

Within the Conowingo Project, wetlands are prevalent in the alluvial reach of the 

Conowingo Pond where the river deposits sediment loads. Conowingo Pond generally 

operates with a maximum pool elevation of 109.2 feet, but allows for a maximum 

fluctuation of 9 feet, from elevation 110.2 down to 101.2 feet. The existing wetland and 

riparian habitat distribution is affected by current project operation (and the operation of 

the Muddy Run Project). For example, vegetation in the upstream reaches of Conowingo 

Pond is generally shorter and less abundant than downstream vegetation, as the upstream, 

more-constricted reach is subjected to higher water levels and velocities than lower 

reaches. As the energy conditions diminish downstream, the vegetation becomes more 

prominent, growing on most available rock surfaces. Because Exelon does not propose 

to change Conowingo Project operation, the existing wetland and riparian conditions 

would be expected to remain unchanged, and wildlife habitat would not be affected; 

however, the TNC Flow Regime would stabilize flow below the dam, which could 

benefit wetlands, riparian habitat, and wildlife habitat. In addition, it is likely the more 

stabilized minimum flows would result in less fluctuation in Conowingo Pond, which 

would also benefit wetlands. However, based on our evaluation of Conowingo Pond 

fluctuations in section 3.3.2.2, Water Resources, Environmental Effects, any such benefits 

would be minor.

Maintenance of project facilities and right-of-way

York Haven Power and Exelon manage vegetation around project facilities, 

including the project transmission line at Muddy Run, around powerhouses, and

recreation areas during routine maintenance activities. Vegetation maintenance could 

affect the presence or proliferation of invasive species, rare plant species, and wildlife 

habitat. Neither York Haven Power nor Exelon conducted targeted surveys for rare 

plants at any of the three projects; however, there are multiple rare plant species known to 

historically occur within 0.5 mile of the three projects.

York Haven Power and Exelon propose no specific project maintenance measures, 

invasive species management measures, or rare plant protection measures. However, 

Exelon manages vegetation along the 4.25-mile-long transmission line right-of-way at the 

Muddy Run Project in accordance with American National Standards Institute A300 

standards, which includes Integrated Vegetation Management (IVM). This approach 

provides for managing plant communities in which compatible and incompatible 
224

vegetation are identified, action thresholds considered, control methods evaluated, and 

selected controls implemented to achieve a specific objective. IVM also includes 

provisions for protection of species of concern, wetlands and streams, and cultural 

resources. The portion of the right-of-way within the wire zone77 is managed to promote 

a low-growing plant community dominated by grasses, herbs, and small shrubs less than 

3 feet high. The rest of the right-of-way is managed to promote shrubs and small trees 

lower than 25 feet high at maturity. Exelon uses a combination of manual, mechanical, 

and herbicide control techniques. In addition, Exelon proposes the implementation of an 

SMP at both the Muddy Run and Conowingo projects. The SMP contains shoreline 

vegetation management measures to protect shoreline vegetation wherever feasible and 

sensitive natural resources policies that would limit or restrict land use in areas of rare 

species and wetlands.

There were no recommendations made by stakeholders regarding vegetation 

maintenance at any of the three projects.

Our Analysis

Rare Plants

Although it is possible that rare plant species occur within any of the three 

projects, no rare plant species were observed within the project boundaries during studies 

conducted for the projects. Project maintenance at all three projects would be expected to 

continue similarly to how it has in the past, with vegetation habitats remaining as they 

exist currently. Overall, proposed maintenance activities such as tree trimming, lawn 

care, herbicide use, and building maintenance would create minimal vegetation 

disturbance and result in minimal vegetation removal. As a result, it is expected that if 

rare plant species exist in the project areas they are not likely to be affected by 

project maintenance. 

At the Muddy Run Project, Exelon uses manual, mechanical, and herbicide 

methods to maintain the transmission line right-of-way free of tall-growing species that 

could interfere with line reliability. Again, because this IVM would continue under the 

terms of any new license, any rare plant species that currently may exist in the right-ofway would not be expected to be affected by the proposed project maintenance. The 

proposed SMP at the Muddy Run and Conowingo projects would likely benefit rare plant 

species, if they occur, because it would limit the amount of shoreline vegetation removed 

and, if any rare plants are found during the life of any licenses issued, these locations 

 

77 The wire zone is the section of right-of-way directly under the transmission 

wires and extending outward 10 feet on each side of the wires.
225

would be integrated into the SMP’s sensitive natural resources land use protection 

program. 

Invasive Species

Regular project maintenance activities, such as vegetation mowing, trimming, and 

clearing, and herbicide applications around project facilities, as well as project-related 

recreation facility use at all three projects would create disturbance that could contribute 

to the spread of invasive species. The presence and spread of invasive species could also 

affect rare plant populations by outcompeting such species. At the York Haven Project, 

York Haven Power observed invasive species along road edges and disturbed areas of 

Three Mile Island and at the Muddy Run Project, Exelon observed invasive species along 

the western shore of the power reservoir and areas near recreation facilities and in the 

transmission line right-of-way. All of these areas are routinely disturbed by project 

maintenance and, in some cases, public use. With York Haven and Exelon continuing 

their project maintenance activities, invasive species would continue to exist in the 

project boundaries and could potentially spread. Eradicating or even controlling invasive 

species populations is very difficult, however, because outside activities can continuously 

introduce new populations of invasive species into the project boundary. Because the 

presence and spread of invasive species is an issue that extends far beyond the three 

projects, the effect of project maintenance on invasive species proliferation would be 

minimal. In addition, at Muddy Run, at the location where invasive species could 

directly affect the federally listed bog turtle, Exelon proposes, as part of its Bog Turtle 

Management Plan, to conduct invasive species control measures. The bog turtle is 

discussed further in section 3.3.5.2, Threatened and Endangered Species, 

Environmental Effects. 

Recreation Facilities 

Existing and proposed recreation facilities at the three project areas could cause 

disturbance to wildlife by creating noise and human activities, which cause wildlife to 

leave the area. Proposed recreation facilities would result in the loss of some wildlife or 

possibly rare plant habitat, if any still exists.

York Haven Power does not propose any new recreation facilities. Exelon 

proposes improvements to existing recreational areas within the Muddy Run Project. 

Improvements that would disturb vegetation include: a new boat ramp and shoreline 

improvements at the Muddy Run Campground, and expanding the playground and other 

facilities at the Visitor’s Center. At the Conowingo Project, Exelon proposes several 

recreation facility improvements that would disturb vegetation such as vegetation 

clearing, additional parking spaces, and new docks at Lock 13 and 15; a new parking lot 

and concrete pad for restroom placement at the Cold Cabin Campground; installation of 

new drainage ditches at the Conowingo Creek boat launch; parking lot expansion at the 

Glen Cove Marina; replacing the existing pavilion and removing a portion of the parking 
226

lot at the Conowingo dam overlook; widening access roads, constructing a retaining wall, 

creating additional parking, constructing a new boat launch, and replacing the existing 

launch area at the Fisherman’s parking/Shures landing site; and, constructing a new road 

at the Peach Bottom access. See section 3.3.5.2, Recreation and Land Use Resources, 

Environmental Effects, for additional details describing specific changes made in each 

area. 

Our Analysis

Existing recreation facilities in the three project boundaries are not expected to 

adversely affect wildlife species because it is likely that most wildlife species that occur 

in those areas have adapted to current levels of activity. Some more sensitive wildlife 

species would likely continue to move out of the areas during high recreation use. 

Proposed recreation improvements at Muddy Run and Conowingo are expansions or 

improvements to existing facilities. As a result, increased noise and human activity

would be expected to result in only minor disturbance to wildlife. Proposed recreation 

enhancements at Muddy Run and Conowingo would, however, result in the loss of 

wildlife habitat through the removal of vegetation. Although the exact amount of 

vegetation that would be cleared for the proposed facilities is unknown, the nature of the 

facilities at both Muddy Run and Conowingo is not expected to have a large construction 

footprint outside already disturbed areas. Because all of Exelon’s proposed improvements 

would be at existing sites, most land clearing would likely occur in previously disturbed 

areas. Direct mortality of smaller, less mobile wildlife species could occur; however, 

more mobile species would be expected to disperse into nearby similar habitat. In 

addition, ground disturbance during construction could result in the increased presence 

and proliferation of invasive species. 

Nature-like Fishway Construction at the York Haven Project

York Haven Project

In the Settlement Agreement, York Haven Power proposes, and the Settling 

Parties recommend, the installation of a nature-like fishway at the north end of the main 

dam. Further discussion can be found in section 3.3.2.2, Water Resources, 

Environmental Effects. The nature-like fishway would serve as a primary fish passage 

facility. The facility would consist of an in-river nature-like fishway near the toe of the 

main dam and reaching upstream from the main dam and would be approximately 300 

feet wide. York Haven Power proposes in the explanatory statement filed with the 

Settlement Agreement that during the finalization of the nature-like fishway plans and 

required permitting it would conduct vegetation cover type mapping, wetland delineation, 

invasive species surveys, rare species surveys, a bog turtle habitat assessment, and a bald 

eagle survey in 2014 in the area right around the proposed nature-like fishway. In 

addition, it would follow all necessary steps to submit applications for a section 404 

permit from the Corps and an NPDES Permit for Stormwater Discharge Associated with 

Construction Activities from Pennsylvania DEP in 2015. Interior commented that York 
227

Haven Power should follow conservation measures that protect bald eagles in addition to 

adopting the National Bald Eagle Management Guidelines. 

Our Analysis

Construction of the proposed nature-like fishway would disturb vegetation located 

at the apex of the main dam and abutment with the west shore of Three Mile Island and 

wetlands within the Susquehanna River. Initial construction of the nature-like fishway 

would result in the loss of vegetation and wildlife habitat in the construction footprint. 

During construction, human activity and construction noise would result in a temporary 

disturbance to wildlife in the area. Following construction, wildlife disturbance would 

return to pre-construction conditions. 

Ground disturbance and vegetation removal activities associated with construction 

of the nature-like fishway could disturb or directly affect rare plant and wildlife species 

such as the bald eagle, as well as result in the spread of invasive species or wetland 

impacts. However, because York Haven proposes to conduct all the indicated surveys, 

complete the resource agency consultation required to obtain the section 404 and NPDES 

permits, and follow all protection measures and BMPs contained in any permits they 

receive, including measures to protect any bald eagles identified during surveys and FWS 

consultation, the proposed nature-like fishway would not adversely affect rare terrestrial 

resources. 

Bald Eagle and Osprey Management

Bald eagle and osprey populations occur within the vicinity of all three project 

areas mainly along the reservoirs and river edges. Project recreation and maintenance 

could potentially affect raptors such as the bald eagle and osprey by creating human 

disturbance and cutting trees and vegetation. The Muddy Run transmission line could 

also potentially affect large raptors from electrocutions or collisions.

York Haven Project 

Although York Haven Power does not propose any measures specifically for bald 

eagle, osprey, or raptor management, York Haven Power proposes to conduct a bald 

eagle survey around the proposed nature-like fishway facility. No resource agencies 

recommend any raptor measures at the York Haven Project other than the Settling 

Parties’ recommendation to construct the nature-like fishway facility as included in the 

Settlement Agreement and Interior’s comment that York Haven Power follow 

conservation measures that protect bald eagles and adopt the National Bald Eagle 

Management Guidelines. This is discussed above under Nature-like Fishway 

Construction at the York Haven Project. Overall, even though bald eagles, osprey, and 

other raptors occur in the York Haven project area, because York Haven Power does not 

propose to change the overall minimum flows below the dam or any new recreation 

facilities and the project does not include a transmission line, it would not affect these 

species and they are not analyzed further.
228

Muddy Run and Conowingo Projects

At both the Muddy Run and Conowingo projects, Exelon proposes to implement 

the Bald Eagle Management Plans included in its license applications that provide for the 

management of bald eagle habitat on Exelon lands based on recommendations from the 

FWS National Bald Eagle Management Guidelines and state agency guidance. This 

includes implementing distance and landscape buffers around nesting sites and avoiding 

certain activities during nesting season. In addition, the Bald Eagle Management Plans 

include guidelines for activities around roosting and foraging areas. The plans also 

include provisions for monitoring of nesting, roosting, and foraging sites every 5 years 

and injury and mortality procedures. 

In addition, Exelon proposes, as part of the SMPs at both projects, to implement 

an osprey management policy that states that Exelon would work with state and federal 

agencies to provide appropriate buffers dictated by the types of activities carried out in 

either visual or auditory proximity to nests during breeding and nesting season (January 

to late July). This includes implementation of: (1) nest buffers during the breeding 

season of 330 feet for most activities and larger buffers up to 600 feet for activities with 

the potential to emit excessive noise (which excludes routine project operation and 

maintenance activities); and (2) restriction on herbicide application within 330 feet of 

osprey nests during breeding season. Exelon would also consult with FWS and 

Pennsylvania Game Commission to determine BMPs and obtain applicable permits in the 

event an osprey nest on project transmission line towers is identified as a problem nest 

that needs to be removed or relocated.

For both the Muddy Run and Conowingo projects, Interior recommends under 

section 10(j) that Exelon finalize and implement Bald Eagle Management Plans in 

consultation with FWS, Maryland DNR, and the Pennsylvania Game Commission. The 

management plan would manage bald eagle habitat on Exelon land in accordance with 

recommendations in the National Bald Eagle Management Guidelines (FWS, 2007a) and 

state agency guidance. Bald eagle habitat, including nest sites, forage sites, and 

communal roost sites, would be managed through a range of conservation measures that 

meet the provisions of the Bald and Golden Eagle Protection Act, including incidental 

take of eagles. The range of measures would include seasonal restrictions, distance 

buffers, and landscape buffers. For the Conowingo Project, Interior indicates two 

specific measures that Exelon should reconcile to avoid disturbance of eagle 

concentration areas: (1) enforcement of human traffic restrictions on both sides of 

Roland Island, under the towers in the river, and on the Cecil County side of the river 

where current human activities disturb perching and foraging eagles; and (2) a 

requirement that Exelon release information pertaining to federal regulations that protect 
229

eagles and great blue heron rookeries, and other migratory birds if any lands are 

potentially donated by Exelon.78

Exelon, in its response to Interior’s recommendations on the Conowingo Project, 

states that its proposed Bald Eagle Management Plan was developed in consultation with 

FWS and Maryland DNR. Exelon states that its proposed Bald Eagle Management Plan 

would manage, through a range of measures, bald eagle nest habitat, including nest sites, 

forage sites, and communal roost sites, on Exelon land. Exelon states that it would 

consult with FWS and other pertinent resource agencies to finalize the Bald Eagle 

Management Plan.

Our Analysis

In August 2012, Exelon completed a transmission line avian interaction study 

report for the Muddy Run Project. The report focused on the biology and morphology of 

avian species, environmental factors, and site configuration of the lines and structures. 

Birds that are large in size, such as eagles, osprey, herons, and vultures are thought to 

have a greater risk of mortality around transmission lines due to large body size and wing 

span contacting transmission lines during flight, and nesting on towers. Many avian 

species prefer nesting on these structures because of height and openness overlooking 

foraging areas. 

As part of the study, Exelon conducted bird surveys between April 2010 and 

October 2010 along the 4.25-mile-long transmission line right-of-way that connected the 

Muddy Run powerhouse to the PBAPS north substation. Data collected were used to 

determine the potential risk of electrocution and collision at the project transmission line. 

The study covered 86 observational hours with 1,376 avian sightings and one mortality. 

Large raptors, including bald eagles and osprey, concentrate in a section of the project,

known as the Water Crossing, where the transmission line perpendicularly crosses

Conowingo Pond from the Muddy Run powerhouse to a slope above Muddy Creek Boat 

Launch. The 2012 study determined this area to have a higher collision risk for raptors 

and other birds because the abundance of large species, the configuration of lines 

perpendicular to shorelines in an open/shoreline environment, and the presence of shield 

wires. Electrocution, on the other hand, is not a risk because the separation of the 

transmission line’s energized and grounded components is larger than the wing span of 

the largest bird in the area. Electrocution is unlikely to occur if a bird is not able to touch 

multiple components at once.

 

78 We interpret Interior’s comment as recommending, in the event that Exelon 

donates land, that Exelon must provide information to the recipient regarding bald eagles 

and other migratory bird species that are present, and the state and federal protection 

afforded to these species. 
230

Overall, although the Water Crossing area of the Muddy Run Project has a higher 

risk for avian collision, the transmission line interaction study documented only one 

mortality with more than 1,376 avian sightings, suggesting that raptor mortality from 

collisions with the transmission line may not be common. Although the study is unlikely 

to have observed every instance of avian mortality and occasional mortality from 

collisions is possible, the Muddy Run Project transmission line is not expected to result in 

adverse effects on raptor populations, including bald eagles and osprey. 

Implementation of the Bald Eagle Management Plan, as proposed by Exelon and 

recommended by Interior, would benefit bald eagles within the Muddy Run and 

Conowingo project boundaries. FWS’ National Bald Eagle Management Guidelines

include active nest protection buffers ranging from 330 feet to 1 mile, depending on the 

nature of disturbance under consideration. By following the proposed Bald Eagle 

Management Plan, Exelon would comply with bald eagle management guidelines and 

state guidelines during construction of recreational facility enhancements, project 

maintenance, and other proposed project measures. In addition, conducting monitoring 

every 5 years would identify new nesting, roosting, and foraging sites and identify sites 

that have been abandoned. This would ensure that future bald eagle nest, roost, and 

foraging areas are also protected by the Bald Eagle Management Plan. Finally, the 

mortality reporting component of the proposed plan would ensure that FWS and the 

Pennsylvania Game Commission are aware of any project-related bald eagle mortality for 

the term of any new license and allow Exelon and the agencies to identify and address 

any increase in project-related mortality. 

At the Muddy Run and Conowingo Projects, both the Exelon proposed and 

Interior recommended Bald Eagle Management Plans would result in the same benefit to 

nesting, roosting, and foraging bald eagles. At the Conowingo Project, Interior’s 

recommendation for restrictions to human activity in the vicinity of eagle concentration 

areas would result in greater protection of foraging and communal roosting bald eagles 

from human disturbance. As Exelon has not proposed to donate lands as part of the 

proposed project, it is not necessary at this time to include a measure in the proposed 

Bald Eagle Management Plan that would require Exelon to release information on bald 

eagles or other migratory species to a recipient.

Similar to the bald eagle, Exelon’s proposed osprey management policy would 

result in landscape and seasonal buffers around osprey nests. By implementing 

appropriate buffers, as determined in consultation with FWS and Pennsylvania Game 

Commission, Exelon is likely to protect the osprey during construction of recreational 

facility enhancements, project maintenance, and other proposed project measures. In 

addition, it would ensure that Exelon follows BMPs identified by FWS and the 

Pennsylvania Game Commission and obtains necessary permits before removing active 

osprey nests. Overall, the proposed policy would benefit the osprey by enacting 

protection measures.
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Waterfowl Nesting Protection 

Waterfowl nesting habitat is present in wetland and riparian habitat. As a result, 

project operations that result in water level fluctuations in project reservoirs or varying 

flows downstream could flood waterfowl nests.

York Haven Power and Exelon do not propose measures related to waterfowl

protection, and waterfowl nesting protection was not identified as a concern by resource 

agencies or other stakeholders at the York Haven or Muddy Run projects.

For the Conowingo Project, Interior recommended under section 10(j) that Exelon 

develop a waterfowl nesting protection plan in consultation with FWS. The plan would 

identify waterfowl nesting areas within the project area that are vulnerable to flooding 

during nesting season, and create a range of alternatives and recommendations to avoid 

flooding active nests.

Exelon, in its response to Interior’s recommendation, states that there is no 

evidence that Conowingo Project operation affects waterfowl or that a waterfowl 

protection plan would be necessary. Exelon states that it was not asked to conduct an 

assessment of the effects of project operation on waterfowl during the relicensing 

process. In addition, Exelon states that the zone of fluctuation around Conowingo Pond 

does not provide waterfowl nesting habitat and that project fluctuations around 

Conowingo Pond and flows downstream of the dam would not affect foraging habitat. 

Our Analysis

Exelon does not propose to change project operation at the Conowingo Project; 

however, project operation would continue to result in fluctuations of Conowingo Pond 

of up to 9 feet. In addition, waterfowl nesting downstream of the Conowingo Project 

could be affected by proposed seasonal fluctuations in flow, specifically the increase in 

minimum flow, from 3,500 cfs in March to 10,000 cfs in April, during the early stages of 

waterfowl nesting. Although we acknowledge that the fluctuation zone of Conowingo 

Pond does not provide much waterfowl nesting habitat and nesting success would not 

likely decrease from existing conditions, implementation of a waterfowl nesting 

protection plan, as recommended by Interior, would identify areas where waterfowl 

nesting habitat is affected by inundation. If project-related effects on waterfowl nesting 

are identified, then such a plan would then allow appropriate protection or mitigation 

measures to be established. Overall, implementation of a waterfowl nesting protection 

plan at the Conowingo Project, in consultation with FWS and the state agencies, would 

benefit nesting waterfowl by allowing Exelon to determine if the Conowingo Project is 

affecting waterfowl nesting habitat, identifying which species of nesting waterfowl the 

project is affecting, and establishing appropriate protection or mitigation measures. In 

addition, the TNC Flow Regime would result in more stable minimum flows during 

waterfowl nesting season, which could result in less flooding downstream of the dam and 

around Conowingo Pond.
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Northern Map Turtle Management

The northern map turtle is known to occur at several locations along the 

Susquehanna River both above and below Conowingo dam, including Wood Island, the 

town of Port Deposit, and Octoraro Beach. Operation of the Conowingo Project, 

including changes in minimum flow releases could affect map turtle nesting and basking 

sites. Maryland DNR comments that Exelon failed to address effects on the map turtle, 

which occurs upstream and downstream of Conowingo dam. It states that constant water 

level changes from the Conowingo Project affect map turtle basking sites, nesting areas, 

and egg production and viability. 

The Nature Conservancy and Interior recommended an alternative flow regime 

downstream of Conowingo dam, partly to benefit basking northern map turtles. The 

TNC Flow Regime would result in more stable flows downstream of the dam, 

particularly during the spring season.

Exelon, in its response to Maryland DNR’s comment, stated that it has funded 

several map turtle studies through Towson University since 2011; however, at this time 

there is no substantial evidence that project operation is adversely affecting the map turtle 

and that implementing any protection, mitigation, or enhancement measures would be 

premature. Exelon states that it is currently working with the State of Maryland and 

Towson University researchers to develop a plan of study for 2014, which would include 

the following research components: (1) nesting habitat enhancement; (2) assessment of 

ecology and viability of populations upstream of Conowingo; (3) development of 

artificial basking structures to mitigate loss of basking sites; (4) rapid assessment of 

population size to determine population trends; (5) hatchling and juvenile ecology; and, 

(6) working with the State of Maryland to develop potential protection and enhancement 

measures for any identified project-related adverse effects. 

Our Analysis

Towson University conducted interim northern map turtle studies from 2011-2013

that discussed the effect of Conowingo Project operation on the northern map turtle

(Seigel et al., 2014). The studies have indicated that turtle nest predation and disturbance 

is prevalent in the Conowingo Project area, particularly at the Octoraro Beach site. 

Encroachment of woody vegetation and brush at the site meant that the turtles had to 

concentrate nests in the few open areas where predators could locate nests more easily. 

Exelon, at Towson’s request made some nesting habitat improvements in 2012 and 

2013, and Towson’s study indicates that these improvements, such as opening up canopy, 

decreased predation and improved nesting success. In 2011, the map turtle predation rate 

was 96.7 percent. Following Exelon’s habitat improvements in 2012 and 2013, the 

predation rates lowered to 44 percent and 66 percent, respectively. Towson stated that 

such habitat manipulations would need to continue biannually to maintain the improved 

conditions. In addition, human disturbance to nesting areas during nesting season is 

likely to limit the nesting success.
233

The studies also have shown that basking sites below the dam are affected by 

human disturbance during recreation and could be affected by water level and flow 

changes. According to the 2013 study, kayaks appeared to be the most likely cause of 

disturbance to basking turtles; however, other sources of disturbance include fishing 

boats, speed boats, canoes, and swimmers. Additionally, the seasonal period when boat 

traffic is the heaviest (specifically, June and August) and the time of day when boat 

traffic is heaviest (between 11a.m. and 1p.m.) coincided with the map turtle’s critical 

basking times. The study hypothesized that the disturbance to basking turtles as a result 

of boat traffic during the early summer may lead to reduced production of map 

turtle offspring. 

Although some map turtle disturbance, such as predation, is not a result of project 

operation, fluctuations in river flow and human disturbance from recreational activities 

may be partly project-related. The 2013 study determined that a combination of flow 

rates from the dam in combination with tide level results in water level fluctuations that 

submerge basking sites, limiting the ability of the map turtle to bask. As described above, 

initial studies indicate that project operation and project-related recreation could affect 

map turtle nesting and basking success. Although Exelon indicates that it is continuing to 

work with Towson University and the State of Maryland on northern map turtle studies 

and the development of protection, mitigation, and enhancement measures, if Exelon 

develops and implements a formal northern map turtle protection plan, in consultation 

with Towson University and Maryland DNR, that incorporates nest management and

mitigation measures to improve and maintain nesting habitat, create new alternative 

nesting and basking sites, and implement measures to restrict human access to nesting 

sites during nesting season, the project would benefit the northern map turtle. 

In addition, it appears that high flow releases from Conowingo dam may 

contribute to the submergence of turtle basking sites, which in turn could affect 

reproductive success. It is likely that more stable flows, such as those in the TNC Flow 

Regime, would benefit basking turtles by allowing basking sites to be available for 

longer periods. 

Wildlife Species of Special Concern

In addition to the species of special concern discussed above (e.g., bald eagle, 

osprey, and northern map turtle), there are four additional species that are either known to 

occur or could potentially occur within the three project boundaries during the year, for 

breeding, foraging, migration, or overwintering. Neither York Haven Power nor Exelon 

proposed any measures and no stakeholders proposed measures relating to these species 

in response to the Commission’s ready for environmental analysis notice. 

The peregrine falcon has been observed in and around the York Haven Project; 

however, the project contains no suitable nesting habitat other than buildings. In 

addition, York Haven Power does not propose to change existing project operation. 

Because project operation would not change, York Haven Power does not propose any 
234

additional recreation facilities which would increase human disturbance, and project 

maintenance is unlikely to affect falcon habitat it is unlikely that the York Haven Project 

would affect any peregrine falcons that may use the project area.

According to the license applications, black-crowned night-herons were not

observed at either the York Haven or Muddy Run projects; however, this species has 

been observed regularly foraging and roosting in the Conowingo dam tailrace, spillway, 

and around Rowland Island. However, Conowingo Project operation and maintenance, 

and recreation activities at the project, particularly in the portion of Rowland Island 

identified as potential nesting habitat, may affect black-crowned night-heron nesting 

activity. Exelon does not propose to change existing project operation or maintenance, 

nor does it propose any recreation facilities on Rowland Island; therefore, it is likely that 

night-herons the presently forage within the project area would continue to do so. The 

TNC Flow Regime would result in more stable flows below the dam, which could 

improve night-heron habitat suitability. 

York Haven Power and Exelon did not observe the rough green snake during any 

non-targeted surveys in 2010 and 2011. Although potential habitat was identified in the 

Muddy Run Project, no rough green snakes were observed during Exelon’s targeted 

surveys at the Muddy Run Project. It is unlikely that this species would be affected by 

operation of the three projects. Project maintenance in suitable rough green snake habitat 

at the three projects has the potential to cause mortality to individuals, but based on the 

lack of observation, it is unlikely that maintenance would affect this species. Lastly, 

construction of staging areas for the York Haven Project’s nature-like fishway would not 

likely affect this species, as management practices to minimize impacts to wildlife during 

construction would be employed.

Although potential habitat for the northern long-eared bat exists within the three 

project areas, along the riparian forested edges of the river and reservoirs, and forested 

edges along transmission line rights-of-way and recreational areas, neither York Haven 

Power nor Exelon propose any activities that would result in more than a minimal amount 

of tree clearing. Continued vegetation management practices, such as trimming and 

herbicide application, would be unlikely to affect trees large enough to provide roosting 

habitat for bats. Therefore, the York Haven, Muddy Run, and Conowingo projects are 

not likely to affect the northern long-eared bat.

Exelon did not observe the red-bellied turtle during any non-targeted surveys in 

2010 and 2011, nor has it been identified as occurring in the project areas. Although 

potential habitat was identified in the York Haven area, York Haven Power conducted 

protocol-level surveys and did not locate any turtles. Although project operation could 

affect red-bellied turtle habitat, because red-bellied turtles were not observed in the 

project area after a thorough search, this species would not likely be affected.
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Rare, Threatened, and Endangered Species Review for Muddy Run

Pennsylvania DEP filed with the Commission on June 9, 2014 a WQC for the 

Muddy Run Project with a mandatory condition requiring Exelon to conduct an 

evaluation of all state and federal endangered or threatened species that may be present 

within the project boundary every 10 years, and to propose a plan and schedule for 

protection if its evaluation identifies the presence, critical habitat, or critical dependence 

of such species within the Muddy Run project boundary. 

Over the course of any new license, the presence and locations of rare, threatened, 

and endangered species in the Muddy Run project boundary is likely to change. Exelon 

proposes to evaluate all state and federal endangered or threatened species that may be 

present within the project boundary once every 10 years through the term of the license. 

If the evaluation identifies the presence, critical habitat, or critical dependence of 

endangered species, Exelon would propose and, following approval, implement a plan to 

ensure protection of endangered or threatened species.

Although we agree that this measure would allow Exelon to continue to be aware 

of the current rare, threatened, and endangered species populations in the Muddy Run 

Project during the length of any license, the Commission typically includes in its licenses 

a standard license article with a fish and wildlife reopener provision that could be used to 

require changes to project facilities upon Commission motion or as recommended by the 

appropriate federal and state fish and wildlife agencies after notice and opportunity for 

hearing. This standard reopener provision retains authority for the Commission to 

implement any measures that may be needed to protect threatened or endangered species 

or other fish and wildlife resources over the term of any license issued for the project. 

3.3.4 Threatened and Endangered Species

3.3.4.1 Affected Environment

In a letter filed January 4, 2007, Interior provided a list of federally listed species 

that may occur in the project area. Staff also referred to FWS’ website 

(http://ecos.fws.gov/ipac/; accessed March 11, 2014 and May 12, 2014) to gather recent 

information on the potential presence of federally listed threatened and endangered 

species within the counties that contain the three projects, and contacted FWS and 

Maryland DNR regarding a bog turtle record close to Conowingo dam. Six federally 

listed species are known to occur in the vicinity of one or more of the projects: shortnose 

sturgeon (Acipenser brevirostrum), Atlantic sturgeon (Acipenser oxyrinchus oxyrinchus), 

bog turtle (Glyptemys [Clemmys] muhlenbergii), Indiana bat (Myotis sodalis), Delmarva 

Peninsula fox squirrel (Sciurus niger cinereus), and swamp pink (Helonias bullata). 
236

Aquatic Species

Shortnose Sturgeon

The shortnose sturgeon (Acipenser brevirostrum) is a federally listed (endangered) 

species with a range along the Atlantic coast extending from New Brunswick, Canada, to 

Florida. NMFS recognizes 19 distinct population segments (DPSs) occurring in New 

Brunswick, Canada (1), Maine (2), Massachusetts (1), Connecticut (1), New York (1), 

New Jersey/Delaware (1), Maryland/Virginia (1), North Carolina (1), South Carolina (4), 

Georgia (4) and Florida (2). The species typically occurs in coastal tidal rivers and 

spawns in fresh water, sometimes moving substantial distances upstream. Shortnose 

sturgeon have been collected in the Connecticut River as far upstream as the Holyoke 

Project, at RM 86. Shortnose sturgeon are not considered anadromous or strongly 

migratory but have been found in brackish and salt water, moving some distance from its 

natal stream (Scott and Crossman, 1973). It is a relatively small sturgeon, seldom 

reaching a length of greater than 35 inches and a weight of 8 or 9 pounds. The 

populations of shortnose sturgeon vary substantially over their range, and it is thought 

that they no longer occur in some tributary rivers to Chesapeake Bay, including the 

Susquehanna. The nearby Delaware River, however, has been estimated to have a stable 

shortnose sturgeon population of from 10,000 to 20,000 fish, based on several population 

estimates. Delaware River fish are able to access the lower Susquehanna River via the 

Chesapeake and Delaware Canal, which connects Delaware Bay to the upper 

Chesapeake Bay.

Documented shortnose sturgeon occurrences in the Susquehanna River in recent 

years have been limited, with only a total of five fish reported. Three fish were recorded 

at the mouth of the river on the Susquehanna Flats, and two fish were reportedly caught 

by anglers in the Conowingo tailrace. No shortnose sturgeon are known to have been 

collected or passed via the Conowingo fish lifts since they began operation in 1972 

(Normandeau and Gomez and Sullivan, 2012l). Additional shortnose sturgeon have been 

collected in upper Chesapeake Bay, but analysis of genetic samples found that the source 

of these fish was likely Delaware Bay. In 2010 and 2011, Exelon conducted monitoring 

for acoustically tagged shortnose and Atlantic sturgeon in the lower Susquehanna River 

downstream of Conowingo dam near Port Deposit and downstream of the I-95 bridge. 

The objective was to determine if any sturgeon acoustically tagged by other researchers 

in Chesapeake and Delaware bays made forays into the Susquehanna River. No tagged 

fish were recorded. 

Exelon assessed Susquehanna River shortnose sturgeon (and other species) habitat 

downstream of Conowingo dam in the 4.5-mile non-tidal reach ending just upstream of 

Port Deposit (Gomez and Sullivan Engineers and Normandeau Associates, 2012). 

Shortnose sturgeon was selected as one of the target species of special concern, and the 

analysis found that there is suitable habitat for all sturgeon life stages in this reach of the 

river at a range of flows modeled.
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Atlantic Sturgeon

The Atlantic sturgeon (Acipenser oxyrinchus oxyrinchus) is also federally listed 

with a range along the Atlantic coast from Maine to Florida. NMFS recognizes five 

DPSs: Gulf of Maine, New York Bight, Chesapeake Bay, Carolina, and South Atlantic. 

Atlantic sturgeon are listed as threatened in the Gulf of Maine DPS and endangered in the 

remaining four DPSs. Atlantic sturgeon are considered an anadromous species, spawning 

in freshwater in the spring and early-summer and returning to estuarine or marine waters 

where they spend most of their lives. Atlantic sturgeon are believed to be present in 32 

rivers along the Atlantic coast, with spawning occurring in 20 of those rivers. Atlantic 

sturgeon are larger in size than shortnose sturgeon, and may reach a length of 14 feet and 

up to 800 pounds 

(http://www.nmfs.noaa.gov/pr/species/fish/atlanticsturgeon.htm#distribution, accessed 

March 7, 2014). 

Atlantic sturgeon are commonly reported in Chesapeake Bay, particularly during 

the winter months, but none have been documented in the Susquehanna River, other than 

anecdotal reports. As with shortnose sturgeon, there is evidence that Atlantic sturgeon 

may use the Chesapeake and Delaware Canal for movement between the Chesapeake and 

Delaware bays. No Atlantic sturgeon have been collected in the Conowingo dam fish 

lifts since beginning operations in 1972. Exelon’s instream flow study (Gomez and 

Sullivan Engineers and Normandeau Associates, 2012a) did not use Atlantic sturgeon as 

an evaluation species, but did include the species in the “deep slow” and “deep fast” 

habitat guilds, and found suitable habitat for all Atlantic sturgeon life stages in the lower 

Susquehanna River. 

Bog Turtle

The bog turtle (Glyptemys [Clemmys] muhlenbergii) is a federally listed species 

(threatened) that has been documented at the Muddy Run Project, and has the potential to 

occur at the York Haven and Conowingo projects. The bog turtle was listed as threatened 

under the ESA in 1997. The bog turtle is also listed by Maryland DNR as a threatened 

species, and by Pennsylvania FBC as an endangered species. 

The bog turtle is native to the eastern United States and ranges from Georgia to the 

lower New England states. In Pennsylvania, extant populations of bog turtle are known 

from 14 counties (including Lancaster and York) located primarily in the southeastern 

quadrant of the Commonwealth. Bog turtle populations are also known from the vicinity 

of Conowingo dam in adjoining Harford County, Maryland.

Bog turtles inhabit distinct types of headwater wetland habitats that include 

spring-fed hydrology and loose, saturated soils. Small spring-courses, rivulets, and 

shallow pockets of surface water typify the surface hydrology of bog turtle wetlands. 

Subterranean tunnels that access flowing groundwater are often used by bog turtles as 

hibernacula for winter brumation and as refugia during the hot summer months. Deep, 

loose, saturated soils (unofficially described as “mucky”, and not to be confused with 
238

muck) in which bog turtles can burrow are an important component of their habitat. Ideal 

bog turtle wetlands contain mostly emergent vegetation with open canopy (minimal 

woody species), though some shrubs and small trees may be scattered throughout.

Bog turtles in Pennsylvania typically emerge from hibernation in March or early 

April, and return to hibernacula in late October to November, depending on weather 

conditions. Breeding occurs from late April through early June, with nesting in 

Pennsylvania occurring from June through early July. Turtles typically lay eggs within or 

on top of suitable vegetation such as sedges or sphagnum moss. Hatchlings emerge from 

the nest August through September and overwinter near their nest. 

York Haven Project

Although the York Haven Project is located within the range of the bog turtle, 

York Haven Power did not conduct specific surveys during its relicensing proceedings. 

Potential habitat for bog turtles may exist within the project boundary, mostly on the 

southern section of Three Mile Island within the relatively large wetland complexes, 

York Haven Power noted several small fringe riparian wetlands along the banks of the 

east channel and in isolated pockets below the main dam and headrace wall, but the 

frequent flooding of these wetlands during high-flow periods likely makes these habitats 

unsuitable for bog turtles. The wetland habitat located on Three Mile Island within the 

project boundary may provide habitat for bog turtles; however, no bog turtles were 

observed during the Eastern Redbelly Turtle Phase II Presence/Absence and Nesting 

Survey or any other surveys conducted in 2010 or 2011. York Haven Power indicates 

that it will conduct a bog turtle habitat assessment in the vicinity of the nature-like 

fishway during the 2014 field season.

Muddy Run Project

The Muddy Run Project is located within the range of the bog turtle. Exelon 

conducted studies during the spring and summer of 2010 and 2011 to identify potential 

habitat for herpetofaunal species within the Muddy Run Project area. Qualified 

biologists searched all land areas to identify potential habitats. Of the six wetlands 

identified within the project study area, four wetlands were not potential habitat and did 

not warrant further surveys, and two wetlands were potential habitat. Bog turtles were 

found to occupy one wetland within the project study area during surveys in June 2011. 

Conowingo Project

According to the Muddy Run bog turtle report, bog turtles are known to exist in 

the vicinity of Conowingo dam in adjoining Harford County, Maryland. Exelon 

conducted surveys in 2008 and determined that none of the 31 wetlands surveyed around

Conowingo Pond contain suitable bog turtle habitat. As documented in telephone and email memoranda filed April 23, 2014, and June 9, 2014, FWS staff stated that a bog turtle 

was sighted close to Conowingo dam in 2013, and directed Commission staff to contact 

Maryland DNR for further information. However, at the time of the issuance of this 
239

document, FWS and Maryland DNR have not provided specific information on the 

location of the bog turtle sighting.

Terrestrial Species

Indiana Bat

The Indiana bat (Myotis sodalis) was originally listed as endangered under the 

Endangered Species Preservation Act of 1966. Currently, the Indiana bat is federally 

listed as endangered. This species, mainly dominant in Indiana, ranges from Florida 

north to Vermont and extending as far west as Eastern Oklahoma. It could potentially 

occur throughout Pennsylvania. The Indiana bat is a temperate, insectivorous, migratory 

bat that hibernates colonially in caves and mines in the winter. Spring migration to new 

habitat happens from mid-March to mid-May. During spring months, females migrate, 

forming maternity colonies to raise their young in wooded areas. Males and nonreproductive females remain near their location for winter hibernation or migrate to 

summer habitat. Summer colony roosts are typically behind exfoliating bark of large, 

often dead, trees (typically >5 inches dbh) where individuals roost in similar smaller trees 

(as small as 3 inches dbh). Between mid-August and mid-October, males and females 

return to their dwelling to hibernate. During winter months, Indiana bats are restricted to 

underground dwelling, but during summer month’s female roosts seek out forested 

habitat. Roosting Indiana bats prefer the bark of dead trees that retain large, thick slabs 

of peeling bark, such as shagbark hickory and oaks, that are usually located within 

canopy gaps, along fence lines and wooded edges. Indiana bats typically roost in riparian 

zones, forested wetlands and upland communities, and forage along forested edges and 

within forested and riparian areas (FWS, 2007). 

Delmarva Peninsula Fox Squirrel

The Delmarva Peninsula fox squirrel (Sciurus niger cinereus) is federally listed as 

endangered. Historically, the fox squirrel was found within the eight counties in the 

Delmarva Peninsula of Delaware, Maryland, and Virginia, including Cecil County. 

Although SD1 indicated that the Delmarva Peninsula fox squirrel would be assessed, the 

FWS website indicates that this species is not currently known to occur in Cecil County, 

Maryland (FWS, 2014c). Therefore, we do not analyze it further in this document.

Swamp Pink

Swamp pink (Helonias bullata) is federally listed as a threatened plant species. 

New Jersey contains the majority of the remaining populations of the species; however, 

according to FWS, the species is known to occur or is believed to occur in Cecil County 

(FWS, 2014b). Swamp pink belongs to the lily family and is characterized by a hollow 

flower stem (1 to 3 feet tall), evergreen, lance shaped leaves that lay flat on the ground, 

and topped by a cluster of pink flowers (FWS, 2006). Swamp pink inhabits forested and 

scrub-shrub wetlands usually bordering meandering streamlets, headwater wetlands, and 
240

spring seepage areas, although swamp pink is limited to perennial saturated wetlands that 

are not inundated by floodwater. Ideal swamp pink habitat contains mainly shaded 

forested areas with the water close to surface level fluctuating little during the spring and 

summer. 

Because the swamp pink is not listed by FWS as occurring in the counties 

occupied by York Haven or Muddy Run projects, these projects would have no effect on 

the species and it is not analyzed further in this document. Although Exelon did not 

conduct targeted swamp pink surveys at the Conowingo Project, and no swamp pink 

communities were incidentally observed during any of Exelon’s 2010 and 2011 field 

survey activities, potential habitat may occur within the Conowingo Project area in 

forested wetland, riparian habitat along the river and reservoir edges and Rowland Island. 

3.3.4.2 Environment Effects

Shortnose and Atlantic Sturgeon

Both sturgeon species have been reported in the Chesapeake and Delaware bays, 

but neither species has been documented in the lower Susquehanna River or in the 

Conowingo tailrace, other than anecdotal reports.

Our Analysis

Neither sturgeon species has any possibility of occurring near the York Haven 

Project, unless they were to pass upstream through the existing fish lifts at the 

Conowingo, Holtwood, and Safe Harbor projects. None, however, have been recorded 

passing these projects since the fish lifts began volitional passage in 1997. No sturgeon, 

likewise, have ever been reported at the Conowingo fish lifts since they first began 

operations in 1972. While there is suitable habitat downstream of Conowingo for both 

species, there is no evidence of their occurrence in the lower Susquehanna River. 

Therefore, continued operation of the York Haven, Muddy Run, and Conowingo projects 

would not likely adversely affect the shortnose and Atlantic sturgeon. 

Bog Turtle

No bog turtles are known to occur within the York Haven project area. 

Nevertheless, there is potential habitat in the vicinity of the proposed nature-like fishway 

and construction activities could affect any turtles occupying that area. As bog turtles 

have been confirmed within the Muddy Run Project area, recreation and maintenance 

activities that occur within the Muddy Run Project boundary have the potential disturb 

bog turtles or habitat. Interior, in its January 31, 2014, letter, states that bog turtles and 

habitat are present near Conowingo dam.

York Haven Power proposes to conduct bog turtle surveys at the proposed naturelike fishway site during the 2014 field season. York Haven Power would provide the 

results of the field studies to applicable agencies for review and adhere to any provisions 

contained in state or federal wetland permitting and NPDES permitting. In addition, 
241

Interior commented that York Haven Power should contact the FWS Pennsylvania Field 

Office prior to any land-clearing activity. 

Exelon proposes, and Interior recommends, the finalization and implementation of 

the Bog Turtle Management Plan for the Muddy Run Project, in consultation with FWS 

and Pennsylvania FBC. Both the Exelon proposed and the Interior recommended Bog 

Turtle Management Plan would include three components: (1) restriction of mowing in 

the wetland documented to support bog turtles; (2) invasive plant and woody plant 

control, particularly for reed canary grass; and (3) possible limits on public access to the 

wetland without advertising the reason. 

Exelon does not propose any specific bog turtle measures at the Conowingo 

Project. Interior recommends79 under section 10(j) that Exelon develop and implement a 

bog turtle management plan in consultation with FWS, Pennsylvania FBC, and Maryland 

DNR as appropriate. The bog turtle management plan would include three components: 

(1) restriction of mowing in the wetland documented to support bog turtles; (2) invasive 

plant and woody plant control, particularly for reed canary grass; and (3) possible limits 

on public access to the wetland without advertising the reason. 

In its response to Interior’s 10(j) recommendation at the Conowingo Project, 

Exelon indicates that no study requests were made at the Conowingo Project for bog 

turtle and therefore it cannot respond to Interior’s statement that the bog turtle is known 

in the project area. Exelon indicates that if there is a known bog turtle record in the 

Conowingo Project area, the record information and a study request should have been 

provided by Interior during the relicensing study plan development process. As 

previously mentioned, staff has been unable to obtain the location of the bog turtle record 

from Maryland DNR or FWS as of the time of this document issuance.

Our Analysis

York Haven Project

Construction of the nature-like fishway has the potential to affect potential bog 

turtle individuals and habitat located on Three Mile Island; however, York Haven Power 

states that it would conduct bog turtle habitat assessments and surveys prior to 

construction to determine if bog turtles exist in this area. York Haven also proposes to 

 

79 Although Interior states in its January 31, 2014, terms and prescriptions letter 

that bog turtles are known to exist near “the dam” and makes a 10(j) recommendation 

that Exelon develop and implement a bog turtle management plan, it is not clear where 

the bog turtle record near Conowingo dam is located. According to the April 23, 2014 

and June 9, 2014, telephone and e-mail memoranda, staff have requested this location 

from FWS and Maryland DNR, but as of the time of the issuance of this document, has 

not received it. 
242

consult with FWS and Pennsylvania FBC, and adhere to any protection or mitigation 

measures recommended by the agencies, such as time of year restrictions or preconstruction exclusion surveys, as part of required permits. Therefore, by following the 

above measure construction of the nature-like fishway at the York Haven Project may 

affect, but is not likely to adversely affect, the bog turtle.

Muddy Run Project

Recreational and maintenance activities that occur within the Muddy Run Project 

boundary could affect known bog turtles if protection measures are not implemented. 

Maintained trails currently traverse the habitat, increasing accessibility to the area and the 

potential for habitat disturbance. These recreation trails would continue to be used in the 

same manner under any new license for the project. Exelon’s proposed Bog Turtle 

Management Plan includes measures to prevent the public from veering off the trails and 

protocols for maintaining the habitat and trails. In addition, invasive species such as reed 

canary grass and mowing in the bog turtle wetland during the bog turtle’s most active 

time could decrease the habitat quality and affect the bog turtle population health. 

Exelon’s plan would ensure that invasive species are controlled in the area and the 

wetland is not affected by vegetation management during the emergence and breeding 

season. If the Exelon-proposed and Interior-recommended Bog Turtle Management Plan 

is developed and implemented by Exelon, in consultation with FWS and Pennsylvania 

FBC, it would protect the turtle by restricting access to the area, restricting mowing, and 

controlling invasive species. Through implementation of the Bog Turtle Management 

Plan, in consultation with FWS and Pennsylvania FBC, the Muddy Run Project would be 

not likely to adversely affect the species.

Conowingo Project

During relicensing proceedings, Exelon determined that none of the 31 wetlands 

surveyed in 2008 at Conowingo Pond contained potential bog turtle habitat and neither 

Interior, nor Maryland DNR, nor Pennsylvania FBC requested further bog turtle studies. 

Although Interior, in its January 31, 2014, terms and prescriptions letter states that “[a] 

survey for bog turtle habitat and bog turtles has confirmed their presence near the dam,” 

it does not provide any further details on this study or where specifically the bog turtle 

was found. Exelon, it its reply comments also indicates it has no information on the bog 

turtle wetland Interior references. According to the April 23, 2014, and June 9, 2014, 

telephone and e-mail memoranda, FWS stated that the bog turtle sighting was “close” to 

Conowingo dam. Although Interior states that bog turtles have been observed close to 

Conowingo dam and recommends a bog turtle management plan for the Conowingo 

Project, it has yet to provide evidence to indicate that bog turtles are present within the 

Conowingo Project boundary. Thus, staff cannot presently determine if bog turtles would 

be affected by the Conowingo Project. Further consultation with Interior is necessary to 

determine the potential for project effects and the applicability of Interior’s recommended 

bog turtle management plan.
243

Indiana Bat

All three project areas are located within the range of the Indiana bat. Project 

maintenance, such as cutting trees over 5 inches dbh, could affect the Indiana bat by 

removing potential roosting habitat or causing direct mortality during roosting season. 

Neither York Haven Power nor Exelon proposed any measures directly related to 

the Indiana bat. In addition, no resource agency or other stakeholder recommended any 

Indiana bat measures. In its terms and conditions letters for the three projects, Interior 

did not identify the Indiana bat as species of concern in any of the three project areas.

Our Analysis

Although potential habitat may exist within the three project areas, along the 

riparian forested edges of the river and reservoirs, and forested edges along transmission 

line rights-of-way and recreational areas, neither York Haven Power nor Exelon propose 

any activities that would result in more than a minimal amount of tree clearing. At the 

Muddy Run Project, continued routine vegetation management practices, such as 

trimming and herbicide application, would be unlikely to affect trees large enough to 

provide roosting habitat. Therefore, York Haven, Muddy Run, and Conowingo projects 

would not be likely to adversely affect the Indiana bat. 

Swamp Pink

Although the swamp pink is known or is believed to occur in Cecil County, where 

the Conowingo Project is partly located, the FWS Information, Planning, and 

Conservation System website (FWS, 2014c) indicates that swamp pink has not been 

documented within the specific project area. Because this species does not appear to

occur in the immediate project area, the Conowingo Project would have no effect on the 

swamp pink. 

3.3.5 Recreation and Land Use Resources 

3.3.5.1 Affected Environment

Regional Resources

Recreation resources in the region provide a full range of activities, including 

boating, canoeing, swimming, fishing, water sports, hiking, camping, hunting, biking, 

and nature viewing. Lakes and reservoirs in the region, including the project reservoirs, 

provide a variety of recreation opportunities and varying levels of developed facilities for 

overnight and day-use activities. Paved roads and boat launches in the area provide 

opportunities for motorized boat use. The varying physical characteristics of the area 

provide for diverse recreational opportunities. 

Safe Harbor and Holtwood hydroelectric reservoirs are located downstream of 

York Haven and upstream of Conowingo and Muddy Run. These FERC-licensed 

projects provide water-oriented recreation opportunities such as fishing, boating, 
244

swimming, and nature viewing that are similar to those offered at the projects analyzed in 

this document. 

Susquehannock State Park is located on the eastern shore of Conowingo Pond 

downstream of the Muddy Run powerhouse, adjacent to the Muddy Run Project 

boundary and just outside the Conowingo Project boundary. The park is about 224 acres 

and offers recreational opportunities including scenic views from the 380-foot-high cliffs 

that overlook the river, picnicking, hiking/walking and horseback riding trails, and 

organized group overnight camping. 

The lower section of the Susquehanna River Water Trail (see 

http://www.susquehannawatertrail.org/) extends from Harrisburg, Pennsylvania, to the 

Broad Creek Public Landing just below the Pennsylvania/Maryland state line (about

53 miles) and is part of the Chesapeake Bay Gateways and Watertrails Network and a 

designated National Recreation Trail.

Ferncliff Wildflower and Wildlife Preserve in Lancaster County is a designated 

National Park Service National Natural Landmark.80 The preserve is located on the east 

side of Conowingo Pond across from the PBAPS and encompasses old growth forest and 

wooded ravines home to plants common to the region. The preserve was established in 

1972 due to the exceptional old growth forest and seasonal wildflowers at this 65-acre 

site, which has a short (0.62-mile) hiking trail for visitors. The preserve lands are 

privately owned and open to the public. 

The Mason-Dixon Trail is a 193-mile-long trail that connects the Appalachian 

Trail with the Brandywine Trail. The trail begins in Cumberland County, Pennsylvania, 

travels east towards the Susquehanna River where it follows the western shoreline south 

to Havre de Grace before heading across the river and north to its terminus at Chadds 

Ford, Pennsylvania. The Appalachian Trail is a 2,180-mile-long continuously marked 

footpath along the crests and valleys of the Appalachian mountain range from Springer 

Mountain, Georgia, to Katahdin, Maine. The Brandywine Trail is a 36-mile-long trail 

along the East Branch of Brandywine Creek and the Brandywine River in Delaware. 

Sections of the Mason-Dixon Trail cross Exelon-owned land. 

The Conestoga Trail is a 61-mile-long trail that begins in Furnace Hills where it

intersects with the Horse-Shoe Trail, before meandering throughout Lancaster County,

Pennsylvania and reaching its terminus with the Mason-Dixon Trail. Near the Muddy 

Run Project, the trail travels near the northwestern section of the Muddy Run WMA, 

 

80 The National Landmark Program is administered by the National Park Service 

and recognizes and supports the voluntary conservation of outstanding geological and 

biological sites, regardless of ownership. Land acquisition by the federal government is 

not a goal of the program. 
245

before travelling across Holtwood Road, Route 372, to intersect with the MasonDixon Trail.

Public Recreation Sites around the Projects

York Haven Project

Recreation facilities available at the York Haven Project include boat launches, 

fishing platforms, a portage trail, nature trails, and day-use areas with picnic facilities,

ball courts, and a catwalk fishing platform on the side of the powerhouse. Lake Frederic 

contains five significant islands (Battery, Beshore, Goodling, Goosehorn, and Shelley) 

with picnic facilities and nature trails provided and maintained by York Haven Power. 

Beshore Island currently only includes York Haven Power-licensed recreational lot sites 

and a boat launch. In addition, Lake Frederic contains several smaller islands that do not 

have facilities, but may be accessed by boaters. Camping and overnight use of the 

islands outside a recreational lot lease is prohibited. None of the publicly available 

recreation sites accommodate overnight use. Fishing platforms are provided in the 

headrace and tailrace areas. The tailrace fishing access is located on a walkway along the

downstream face of the powerhouse. The land immediately adjacent to the York Haven 

Project powerhouse provides a playground and picnic facilities as well as tennis and 

basketball courts and ample parking. A 0.25-mile portage trail is provided on the right 

bank at this location.

There are five boat launches within the project boundary owned and operated by 

York Haven Power or public entities: Newberry Township Boat Launch, Beshore Island 

Boat Launch, Goldsboro Borough Boat Launch, Pennsylvania FBC Boat Launch, and the 

East Shore Boat Launch (figure 3-18). Additionally, the Falmouth Boat Launch, owned 

and operated by Pennsylvania FBC, is located on the eastern shore of the Susquehanna 

River, downstream of the dam and across the river from the powerhouse. Although this 

boat launch is located outside of the project boundary, it often is used to gain access to 

the project spillway and tailrace. Three privately owned marinas and boat launches are 

also present along the shoreline of Lake Frederic. Fuel is available at Goldsboro Marina, 

Tri County Boat Club, and the Riverside Marina. Table 3-30 summarizes the recreation 

sites at the York Haven Project.
246

Figure 3-18. York Haven Project recreation facilities (Source: York Haven Power, 

2012, as modified by Staff).
247

Table 3-30. Recreation sites at the York Haven Project (Source: York Haven 

Power, 2012, as modified by Staff).

Site Name Owner

Project 

Facility

Facilities and 

Opportunities

Annual 

Estimated Usea

(Historic) Canal Lock York Haven 

Power

Yes Abandoned canal lock, 

picnic area

596

East Shore Boat 

Launch

York Haven 

Power

Yes Boat launch, trail, picnic 

area

1,580

Goosehorn Island 

Picnic Area

York Haven 

Power

Yes Picnic area 3,908

Shelley Island 

Recreation Area

York Haven 

Power

Yes Recreational lots, picnic 

area, interpretive display, 

nature trail, historic 

cemetery

123

Goodling Island York Haven 

Power

Yes Picnic Area 740

Pennsylvania FBC 

Boat Launch

Pennsylvania 

FBC

No Boat launch 6,903

Goldsboro Borough 

Boat Launch

Goldsboro 

Borough

No Boat launch 235

Beshore Island 

Recreation Area

York Haven 

Power

Yes Recreational lot sites not applicable

Battery Island 

Recreation Area

York Haven 

Power

Yes Picnic area 1,292

Newberry Township 

Boat Launch (Falls 

Landing)

Newberry 

Township

No Boat launch 1,006

Cly Shore York Haven 

Power

Yes Recreational lot sites not applicable

York Haven Power 

Plant Recreation Area

York Haven 

Power

Yes Visitor’s center, fishing 

pier, tailwater fishing, 

playground, picnic area, 

sport court

944

Canoe Portage Trail York Haven 

Power

Yes Canoe portage 28

a Estimated from spot counts conducted over 32 days throughout the year; estimate 

presented is the highest recorded number of visitors to each site observed during all 

visits to each site.
248

Muddy Run Project

At the Muddy Run Project, existing formal recreation opportunities include the 

Muddy Run Park and Campground, Wissler’s Run Park, and Muddy Run WMA 

(figure 3-19). Exelon owns all of the lands used for recreation at the Muddy Run Project, 

and leases the operation of Muddy Run Park and Campground and the Muddy Run WMA 

to other parties. Exelon reports two informal recreation areas exist within the Muddy 

Run Project boundary. These are areas without developed recreation infrastructure and 

are not managed or maintained as such by any entity. The sites provide fishing access or 

informal boat launch access to the project. 

The 800-acre Muddy Run Park and Campground is located in the northern section 

of the project boundary. Within the park is the 100-acre Recreation Lake, separated from 

the Muddy Run reservoir by a dam and concrete sill that maintains a stable water 

elevation. The park is operated by a vendor, and the developed portion of the park 

includes overnight and day-use facilities. A 189-site campground with showers, 

playgrounds, covered picnic pavilions, and many other amenities is located on the 

northern shore of the Recreation Lake. The park also provides numerous separate 

facilities including picnic areas, trails, an outdoor amphitheater, ball field, sport courts, 

restrooms, wildlife viewing areas, and shoreline fishing opportunities. Boat rentals 

(canoes, kayaks, paddleboats, rowboats) are available at the park, as well as a boat ramp 

for visitors to launch their own boats. Gasoline-powered boats, swimming, and wading 

are not allowed in the Recreation Lake. A visitor’s information center contains displays 

(static and interactive) and meeting rooms. The center also is used for park-related 

programs and rental functions. Table 3-31 summarizes the recreation facilities associated 

with the Muddy Run Project.
249

Figure 3-19. Muddy Run Project recreation facilities (Source: Exelon, 2012a, as 

modified by Staff).
250

Table 3-31. Recreation facilities in the Muddy Run Project area (Source: Exelon, 

2012a, as modified by Staff).

Site Name Owner Project 

Facility

Facilities and 

Opportunities

Annual 

Estimated Use

Muddy Run Park 

and Campground

Exelon 

(leased to 

vendor)

Yes Camping, 

picnicking, fishing, 

boating (electric 

motor only), 

playgrounds, 

sports fields and 

courts, etc.

254,000a

Wissler’s Run Exelon Yes Fishing, 

picnicking, 

wildlife/nature 

viewing

5,800b

Muddy Run 

WMA

Exelon 

(leased to 

Pennsylvania 

Game 

Commission)

Yes Hunting, wildlife 

viewing, hiking 

and horseback 

riding

7,500b

a Estimated from a combination of data supplied by facility operator, traffic counts, and 

spot counts over 12 months.

b Estimated from spot counts recorded 6 days a month for 12 months.

Wissler’s Run is located on the eastern shore of Conowingo Pond just downstream 

of the Muddy Run powerhouse. The park provides a large green open space area for 

picnicking, bank fishing, and an overlook of the upper Conowingo Pond and islands. The 

site also includes a non-functioning fish cleaning station. A paved 130-space parking lot 

services the site. The Muddy Run WMA surrounds the southern portion of the Muddy 

Run reservoir. The 800-acre site is leased to Pennsylvania FBC and managed to provide 

food and cover for wildlife, which in turn promotes hunting and wildlife viewing 

opportunities. Two gravel parking areas provide vehicle access to the WMA while 

additional management roads and trails provide access for hunters, hikers, birders, and 

equestrians. 

Within the Muddy Run Project, the Mason-Dixon Trail crosses the transmission 

parcels located in York County, and travels near several recreation sites in the 

Conowingo Project. Exelon entered into a license agreement with the Mason-Dixon Trail 

System, Inc., allowing sections of the trail to be located on Muddy Run Project land.
251

Conowingo Project

The Conowingo Project is the most downstream of the FERC projects on the 

Susquehanna River and offers a large component of recreation opportunities in the lower 

Susquehanna River. There are 15 project recreation public access areas (see figure 3-20). 

Table 3-32 summarizes the public recreation facilities associated with the Conowingo 

Project. Exelon also identifies numerous informal access points around the reservoir and 

downstream of the dam.

Lock 13 is located at the site of the Susquehanna and Tidewater Canal Lock 13. 

The facility is maintained in a primitive state with no public amenities or interpretive 

improvements. Lock 13 is owned and managed by Exelon, but is accessed from the PPL 

Holtwood LLC Lock 12 parking lot (Holtwood Project, FERC No. 1881) via the MasonDixon Trail. Recreation opportunities at Lock 13 include the Mason-Dixon trail and 

shoreline fishing.

Lock 15 is owned and operated by Exelon as a day-use and interpretive area. The 

site has a 36-space gravel parking lot and portable restrooms, and offers picnicking and 

shoreline fishing opportunities. There are interpretive signs on-site that describe the 

Susquehanna and Tidewater Canal system, how the lock worked, and the history of the 

site. A pathway connects the picnic area with the Muddy Creek Boat Launch 

immediately downstream. The Mason-Dixon Trail runs through the site and connects 

Lock 15 with Lock 13 to the north and Muddy Creek Boat Launch to the south.

Muddy Creek Boat Launch is owned by Exelon and leased and operated by 

Pennsylvania FBC. The facility provides shoreline fishing access, a 20-foot-wide hard 

surface ramp, courtesy docks, and portable toilets. The site is serviced by a paved 

parking lot (44 boat trailer spaces and 26 vehicle spaces) and used by both power boaters 

and car-top boaters. The Mason-Dixon Trail connects the site to the Lock 15 

interpretive area.

Cold Cabin Boat Launch is owned by Exelon and managed by Peach Bottom 

Township, which developed the recreation facilities. Amenities include a 12-foot-wide 

hard surface boat launch, informal parking for approximately five vehicles, and a small 

picnic area. The Mason-Dixon Trail passes through this site.

Dorsey Park Boat Launch is located just upstream of PBAPS. Although the 

majority of the site is located outside of the project boundary, the boat ramps extend into 

and provide access to project waters. The site, which is owned and operated by Exelon, 

includes boat launching, shoreline fishing, and picnicking opportunities with several 

tables and grills. Amenities include two 32-foot-wide boat ramps, courtesy docks, a 

paved parking lot (25 boat trailer spaces and 30 vehicle spaces), portable toilets, picnic 

tables, and grills.
252

Figure 3-20. Conowingo Project recreation facilities (Source: Exelon, 2012b, as 

modified by Staff).
253

Table 3-32. Recreation facilities in the existing Conowingo Project boundary

(Source: Exelon, 2012b, as modified by Staff).

Site Name Owner

Project 

Facility

Facilities and 

Opportunities

Annual 

Estimated Usea

Lock 13 Exelon Yes Unrestored site 

with no public 

amenities or 

interpretive 

improvements

782

Lock 15 Exelon Yes Interpretive 

displays, picnic 

tables, bank 

fishing

13,066

Muddy Creek 

Boat Launch

Exelon (leased to 

Pennsylvania 

FBC)

Yes Boat ramp, 

courtesy docks, 

and interpretive 

panels

38,742

Cold Cabin Boat 

Launch

Exelon (leased to 

Peach Bottom 

Township)

Yes Boat ramp, picnic 

tables, and 

interpretive sign

11,968

Dorsey Park Exelon (as part 

of Peach Bottom 

Nuclear Station)

Yes Boat ramp, picnic 

tables, grills, 

benches, and 

interpretive signs

16,706

Peach Bottom 

Marina

Exelon (operated 

by commercial 

operator)

Yes Boat ramp, docks, 

fuel, and boat 

maintenance

538

Line Bridge Exelon (leased to 

Harford County)

Yes Informal 

shoreline access; 

hand launch

5,789

Broad Creek 

Public Landing

Exelon (leased to 

Harford County, 

Maryland)

Yes Boat ramp and 

courtesy dock, 

small open space 

for day use

10,138

Conowingo 

Creek Boat 

Launch

Exelon Yes Boat ramp, 

courtesy dock

10,594
254

Site Name Owner

Project 

Facility

Facilities and 

Opportunities

Annual 

Estimated Usea

Glen Cove 

Marina

Exelon (operated 

by commercial 

operator)

Yes Boat ramp, docks, 

picnic area, fuel, 

repair services, 

store and boat 

slips. Also serves 

as the take out for 

the Conowingo 

dam portage.

707

Funk’s Pond Exelon Yes Shoreline fishing, 

picnic area, and 

pedestrian trail

4,380

Conowingo 

Swimming Pool 

and Visitors 

Center

Exelon (operated 

by commercial 

operator)

Yes Swimming pools, 

picnic tables, 

restrooms, 

playground, and 

visitor center

8,471

Conowingo Dam 

Overlook

Exelon Yes Picnic tables and 

view of the 

powerhouse and 

dam

closed during 

study period

Fisherman’s 

Park/Shures 

Landing

Exelon Yes Shoreline and 

platform fishing, 

carry-in boat 

launch, 

observation areas, 

picnic areas

141,580

Octoraro Creek 

Access

Exelon Yes Creekside trail 

connecting to 

Susquehanna 

River, 

informational 

kiosk

7,485
255

Site Name Owner

Project 

Facility

Facilities and 

Opportunities

Annual 

Estimated Usea

3.5 miles of 

Mason-Dixon 

Trail

Exelon (managed 

and maintained 

by Mason-Dixon 

Trail System, 

Inc.)

No Trail passes 

through Lock 13, 

Lock 15, Muddy 

Creek, Cold 

Cabin, Broad 

Creek, Glen 

Cove, Swimming 

Pool/Visitors 

Center, and 

Fisherman’s 

Park)

No estimate 

available

Lower 

Susquehanna 

Heritage 

Greenway Trail

Exelon (leased to 

State of 

Maryland)

No Paved trail from 

Fisherman’s Park 

to Deer Creek, 

collocated with 

Mason Dixon 

Trail, benches, 

tables, 

interpretive 

displays, and 

boardwalk

No estimate 

available

Susquehanna 

State Park

Exelon (leased to 

State of 

Maryland)

No Camping, 

picnicking, 

shoreline fishing, 

walking trails, 

boat ramps, 

playgrounds, bike 

and equestrian 

riding trails, 

hunting area and 

an archery range

No estimate 

available

Deer Creek 

Access

Part of 

Susquehanna 

State Park

No Informal car top 

boat launch, 

parking and 

shoreline access

No estimate 

available
256

Site Name Owner

Project 

Facility

Facilities and 

Opportunities

Annual 

Estimated Usea

Lapidum Boat 

Launch

Part of 

Susquehanna 

State Park

No Boat ramp, 

parking, 

restrooms, 

interpretive 

displays

No estimate 

available

McLhinney Park Exelon (leased to 

City of Havre de 

Grace)

No Playground, 

picnic area, 

restrooms, green 

space and nonmotorized trails

No estimate 

available

a Estimated from one or a combination of methods depending on the type of site and 

could include spot counts, traffic counters, or facility operator records recorded over 

12 months. 

Peach Bottom Marina is owned by Exelon and operated by a commercial 

contractor. The marina offers boat launching, shoreline fishing, and picnicking 

opportunities. The facility amenities include a 25-foot-wide boat hard surface ramp, a 

paved parking area (17 boat trailer spaces and 33 vehicle spaces), boater courtesy docks, 

tie-up rental space, boat storage, repair shop, portable toilet, fueling facilities, and picnic 

tables. There is a launch fee charged to use the ramp. The marina is located on Peters 

Creek, a tributary on the east side of Conowingo Pond. The Norfolk Southern rail line 

extends along the entire east shore of the pond and access to/from the marina requires 

boating under the train trestle spanning Peters Creek.

The Line Bridge Access site is owned by Exelon and managed and maintained by 

Harford County under an agreement with Exelon. The property provides informal 

shoreline access, a three car parking area, and an unimproved carry-in boat access area.

The Broad Creek Public Landing is owned by Exelon and managed and 

maintained by Harford County under agreement with Exelon. The facility provides a 

hard surface boat launch, small dock, shoreline fishing opportunities, and parking for four 

vehicles. A 33-space boat trailer off-site parking lot was constructed on nearby Paddrick 

Road due to the steep terrain and limited parking available at the boat launch site. The 

Mason-Dixon Trail extends through this site.

The Conowingo Creek boat launch is owned and operated by Exelon. The facility 

provides an 80-foot-wide hard surface boat ramp, two parking areas (one for 9 boat 

trailers and one for 10 vehicles), a small picnic area and shoreline fishing opportunities. 

The site is located on Conowingo Creek, a tributary on the east side of Conowingo Pond. 

The Norfolk Southern rail line extends along the entire east shore of the pond and access 

to/from the ramp requires passing under the train trestle spanning Conowingo Creek.
257

Glen Cove Marina is owned by Exelon and operated by a commercial contractor. 

Recreation opportunities include boat launching and picnicking. Facility amenities 

include a hard surface boat ramp, boat slips, portable toilets, fueling facilities, picnic 

tables, and parking for 16 boat trailers and 20 vehicles. There is a launch fee charged to 

use the ramp. The operator also provides repair services and a small onsite store. This 

facility also serves as the take-out for the Conowingo dam canoe portage. The MasonDixon Trail runs through the site.

Funk’s Pond is a small inlet separated from Conowingo Pond by the Norfolk 

Southern rail line. The “pond” is within the project boundary and accessed from a 

24-vehicle parking lot and trail on adjacent non-project land. The site is owned and 

operated by Exelon. The site provides a non-motorized, 0.45-mile trail, picnicking and 

shoreline fishing opportunities.

The Conowingo swimming pool complex and Visitor’s Center are located just 

upstream of Conowingo dam on U.S. Route 1. The Conowingo swimming pool complex 

is owned by Exelon and operated by a commercial contractor. Pool facilities include a 

swimming pool, wading pool, playground area, picnic area, concession stand, and 

changing/restrooms. The pool is open 11:00 a.m. to 7:00 p.m. from May to September, 

and users are charged an entrance fee. The Visitor’s Center contains informational 

displays and brochures, restrooms, conference rooms, and office space for the Lower 

Susquehanna Heritage Greenway. The center is owned, operated, and staffed by Exelon. 

A small picnic area is also provided. A 213-space paved parking lot is shared by these 

two facilities. The Mason-Dixon Trail extends through the site.

Fisherman’s Park is located on the western shore of the Susquehanna River 

immediately downstream of Conowingo dam and powerhouse. Fisherman’s Park is 

owned and operated by Exelon and is a popular fishing and bird watching area. 

Amenities at the park include shoreline and platform fishing, a carry-in boat launch 

(Shure’s Landing), observation areas, portable toilets, picnic areas, and scenic views. 

This area also serves as a trailhead for the Lower Susquehanna Heritage Greenway Trail 

to Deer Creek and a wildflower viewing area. There is a 124-space paved vehicle 

parking lot, a 14-space paved boat trailer parking lot, and a 12-vehicle gravel parking lot 

associated with this site. The fishing platform is ADA-compliant. The Mason-Dixon 

Trail passes through the lower part of the parking lot. The park is open 1 hour before 

sunrise to 1 hour after sunset.

Exelon investigated tributary access to the main reservoir between full pond 

(109.2 feet) and the minimum weekend recreation pool level (107.2 feet) between 

Memorial Day and Labor Day. Exelon reported that five tributaries provide recreational 

value; four due to the presence of public boat launch facilities, all of which are also 

commercial marinas (Peters Creek/Peach Bottom Marina, Conowingo Creek, Glen Cove, 

and Broad Creek). The fifth tributary, Muddy Creek, provides recreation value due to its 

large size.
258

Shallow water depths due to sediment accumulation limit boat launch egress and 

ingress at Peters Creek (Peach Bottom Marina), Conowingo Creek, and Broad Creek. 

The minimum recreation pool elevation is 107.2 feet. During a field reconnaissance of 

navigability conducted in August 2012 when the pool elevation ranged between 107.32 to 

107.64 feet, Exelon documented that the boat launch and areas immediately surrounding 

the ramp at Broad Creek were not usable for motorized boats due to the shallow water 

and dense vegetation. Water depths leading to the boat launch were generally 2 feet with 

areas near the launch being less than 1 foot. At Conowingo Creek, water depths in the 

main channel were 4.5 feet and 2 feet in the vicinity of the boat launch. At Peters Creek, 

water depths were 4 to 5 feet in the main channel and zero at mud flats exposed at the 

time of the survey. 

Exelon concluded that pond elevations do influence boat access at three of the four 

tributary boat launches. At full pond, boats higher than 5.2 feet above the water cannot 

navigate under the railroad bridge at Peters Creek. Similarly, boats higher than 4.9 feet 

cannot navigate under the railroad bridge at Conowingo Creek. Conversely, the 

minimum weekend recreation season elevation is too shallow to launch a boat limiting 

access from three tributary launches: Peters Creek, Conowingo Creek, and Broad Creek 

ramps. In addition, dense beds of SAV hamper the approach for boaters attempting to 

use these ramps at elevations of 107.2 feet or less. When Conowingo Pond elevation 

reaches 105.9 feet, boat access is denied at three of the four tributary boat launches. 

Recreation in the River Downstream

York Haven Project

Pennsylvania FBC owns and operates the Falmouth Boat Launch located across 

from the York Haven powerhouse on the east shore of the Susquehanna River. The 

launch is outside the project boundary but provides water access, albeit shallow, to the 

bypassed reach, project spillway, and tailrace areas, as well as points further downstream 

within the Safe Harbor reservoir.

Conowingo Project

The Conowingo Project boundary extends 2.5 miles downstream of the dam along 

the east bank of the river and 0.5 mile downstream along the west bank of the river. In 

addition to Fisherman’s Park/Shures Landing, access to the river below the dam within 

the project boundary is provided at the Octoraro Creek Access on the east bank and 

Susquehanna State Park on the west bank. Land based, non-project recreation exists

further downstream along the Lower Susquehanna Heritage Greenway, which provides 

trails and informal access points to the river. Access to the Susquehanna River also is 

available at non-project public launch and commercial marinas downstream of 

Conowingo dam. Public access is provided at Deer Creek Access about 3 miles 

downstream of the dam, Lapidum boat launch, within Susquehanna State Park, about 

5 miles downstream of the dam, in Port Deposit, Maryland, across the river from 
259

Lapidum boat launch, and McLhinney Park (or North Park) in Havre de Grace, which 

provides shoreline fishing and other predominantly passive recreational opportunities. 

Recreation Use

York Haven Project

York Haven Power estimates that the York Haven Project supported more than 

17,000 recreation days81 during the 2008-2009 sampling season. The greatest use occurs 

during weekends during the late May through early September, peak season. The 

Goldsboro Borough Boat Launch was the most visited recreation site (see table 3-30). 

York Haven Power reports that an overwhelming majority of visitors to recreation 

facilities at the project are from Pennsylvania (99 percent), with many of those from the 

local, southeastern region of Pennsylvania, including the Harrisburg, Lancaster, and York 

areas. York Haven Power notes that peak weekend use approaches or exceeds capacity 

when the weather is favorable; however, the sites are capable of absorbing a great deal 

more use if visitors were to shift their use patterns and use the project sites more 

frequently or in greater numbers outside the peak weekends.

During the 2008-2009 recreation study, York Haven Power estimated the physical 

utilization for each recreation site. Table 3-33 shows the parking site utilization rates 

observed during the recreation study. Typically, use of the parking areas is well below 

the capacity; however, both Goldsboro Borough Boat Launch and East Shore Boat 

Launch were observed at or near capacity on holiday weekends. In general, all sites were 

observed well below capacity throughout the peak season.

 

81 A recreation day is considered each visit by a person to a development for 

recreational purposes during any portion of a 24- hour period.
260

Table 3-33. Physical capacity utilization of York Haven Project recreation sites

(Source: York Haven Power, 2012, as modified by Staff).

Site Name

Number of 

Parking 

Spaces

Highest Number 

of Spaces Used on 

Summer Weekend

Average 

Percent 

Utilization

Maximum 

Percent 

Utilization

Pennsylvania FBC

Goldsboro Boat 

Launch

242a 209 23 86

East Shore Boat 

Launch 57 57 31 100

York Haven Power 

Plant Recreation 

Area

31 6 3 19

a Covering three parking areas.

Muddy Run Project

Exelon estimates that the Muddy Run Project supported slightly more than 

267,000 recreation days during 2008-2009, with 95 percent occurring within the Muddy 

Run Park and Campground (see table 3-31). Exelon reports the majority of visitation 

occurs during summer (late May to late August) and that an estimated 21 percent of the 

recreation days spent at the park were coupled with overnight stays (camping). 

Swimming and wading are not permitted at any location within the park, and this 

limitation was cited most frequently in the Exelon visitor survey (27 percent). Activities 

in the WMA vary by season with hunting popular in the fall and winter, and running and 

walking popular in the summer. Wissler’s Run Park saw the greatest usage during the 

spring season (52 percent), followed by summer (35 percent). Sightseeing is the most 

popular activity (71 percent), followed by shoreline fishing (21 percent). 

During its 2008-2009 recreation study, Exelon estimated the physical utilization 

for each recreation site. Table 3-34 shows the utilization rates observed during the 

recreation study by recreation site. 
261

Table 3-34. Physical capacity utilization of Muddy Run Project recreation sites (Source: 

Exelon, 2012b, as modified by Staff).

Site Name Number of 

Parking Spaces

Average Spaces 

Used on Summer 

Weekend

Percent Utilization

Muddy Run Park & 

Campground 582 338 58

Muddy Run WMA 80 3 4

Wissler’s Run Park 130 3 2

 

Conowingo Project

Exelon estimates that the Conowingo Project supported just under 271,000 

recreation days in 2008-2009, with about half of those recorded at Fisherman’s 

Park/Shures Landing immediately downstream of the dam (see table 3-32). The vast 

majority of recreation days were recorded during the summer season. Within the 

Conowingo Project, the top three recreation activities were sightseeing (29 percent of 

total use), shoreline fishing (22 percent), and boating (21 percent). These three activities 

accounted for more than 7 out of every 10 visitors to the project in 2008-2009. 

Exelon conducted a user preference survey that revealed recreation sites within the 

Conowingo Project were well regarded as a whole. Fisherman’s Park received positive 

scores with 9 of 10 respondents giving the park a good or excellent rating. The most 

frequently requested specific improvements throughout the Conowingo Project were 

restrooms, boat ramps, parking, and trash cans/clean-up of site. Highest on the list for 

Fisherman’s Park was the desire to reopen the catwalk on the downstream side of the 

powerhouse for fishing.

During the recreation study, Exelon also estimated the physical capacity utilization 

for each recreation site. Table 3-35 shows utilization rates observed during 2008-2009 by 

recreation site. As the table indicates, many of the sites are used well below the site 

capacity, with the exception of Cold Cabin Boat Launch and Line Bridge, both of which 

offer only a small number of parking spaces. 
262

Table 3-35. Physical capacity utilization of Conowingo Project recreation sites

(Source: Exelon, 2012b, as modified by Staff).

Site Name Number of Parking 

Spaces

Average Spaces 

Used on Summer 

Weekend

Percent Utilization

Lock 13 22 1 5

Lock 15 36 1 3

Muddy Creek Boat 

Launch 69 31 45

Cold Cabin Boat 

Launch 5 5 100

Dorsey Park 57 6 11

Line Bridge 3 3 100

Broad Creek Public 

Landing 41 4 12

Glen Cove Marina 47 22 47

Conowingo 

Swimming Pool and 

Visitors Center

213 80 38

Peach Bottom 

Marina 48 7 15

Conowingo Creek 

Boat Launch 19 3 16

Funk’s Pond 24 2 8

Fisherman’s 

Park/Shures 

Landing

124 34 27

Octoraro Creek 

Access 12 2 17
263

Land Use

Land use in the Susquehanna River Basin is primarily forest (70 percent), 

farmland (22 percent), and urban areas (7 percent). All three projects are located within 

the Lower Susquehanna Subbasin, which exhibits similar land use patterns to the overall 

basin. Harrisburg, the capital of Pennsylvania, is about 17 miles upstream of the York 

Haven Project. Most of the population is centered in the urban areas of Harrisburg, York, 

and Lancaster, all within an hour drive from at least one of the projects. The larger cities 

of Baltimore, Wilmington, and Philadelphia are generally within a 2-hour drive of some 

portion of project waters. 

Below the Conowingo Project, the Susquehanna River flows about 10 miles to the 

head of the Chesapeake Bay at Havre De Grace, Maryland. Counties in the project areas 

include Dauphin, York, and Lancaster in Pennsylvania and Harford and Cecil in 

Maryland. 

York Haven Project

The York Haven Project includes about 3,220 acres, of which York Haven Power 

has acquired fee title and flowage rights to land within the project boundary, and claims 

by easement to all other near shore lands adjoining Lake Frederic. All of the islands 

within the impoundment are within the project boundary except for the portion of Hill 

Island located above the 282.5-foot contour, and the northern portion of Three Mile 

Island, where Exelon’s Three Mile Island nuclear facility is located. The Three Mile 

Island nuclear facility has a 2,000-foot exclusion zone from the two nuclear reactors on 

the site that encompasses a small slice of shoreline on Shelley Island. The lands within 

the exclusion zone on Shelley Island are considered non-project lands located in the 

project boundary. The impoundment is about 3.5-miles-long with approximately 

29 miles of shoreline. The York Haven Project boundary extends about 3.5 miles from 

the top of the impoundment to the downstream face of the dam and powerhouse. There 

are no lands of the United States within the project boundary. 

York Haven Power leases 288 recreational lots at Cly Shore, Shelley Island, and 

Beshore Island. Sites are available to the public for a small fee. Current York Haven 

Power policy does not provide for new permitted recreational lots within the project 

boundary. In addition, permits for existing recreational lots that are abandoned or where 

existing structures become damaged and are not replaced by structures conforming to all 

applicable federal, state, and local regulations would be terminated.

York Haven Power lease conditions and rules require lot residents to comply with 

applicable federal, state, and local laws, including requirements related to potable water, 

sanitation, sewage facilities, waste disposal, and dock placement and use. Lease holders 

are not allowed to cut trees without York Haven’s permission nor plant any nonindigenous or invasive plants on the islands. York Haven Power conducted an 

assessment of the sewage disposal systems by recreational lots on Shelley and Beshore 

Islands and five parcels near Cly Shore. York Haven Power reported that almost every 
264

site had water service through a well or withdrawal from the Susquehanna River and 

every site appeared to have sewage disposal means, either through an outhouse, septic 

tank, or a drain line that went underground. 

The Pennsylvania Sewage Facilities Act and regulations adopted under that 

statute, including the Londonderry Township On-Lot Disposal Systems ordinance, cover 

sewage waste at leased recreational lots. The York Haven Power lot lease states that lot 

lessees are responsible for completing any sewage system upgrades or replacements 

required to comply with these statutes and ordinances.

In 2010, after a sewerage assessment on the islands, York Haven Power prohibited 

the use of water withdrawn from wells or the river for any potable purposes (drinking, 

cooking, showering, dishwashing, oral hygiene, etc.). Lot lease holders are expected to 

provide their own supplies of bottled water for potable purposes. York Haven Power 

further noted that the Pennsylvania Sewage Facilities Act required ordinances related to 

sewage facilities are adopted at the local level and that new language in the local 

ordinance (2012) would force upgrades or replacements at the majority of leased lots. 

York Haven Power lease agreements make it clear this is the responsibility of the lease 

holder.

Muddy Run Project

The Muddy Run Project lands include the 900-acre power reservoir and the 

100-acre Recreation Lake in Lancaster County, and the transmission line corridor that 

spans the Susquehanna River and extends into York County. In total, the project consists 

of about 2,790 acres, 1,790 of which are upland consisting primarily of agricultural fields 

and forested land. The Muddy Run project boundary is irregularly shaped around the 

upper reservoir, parallels the Susquehanna River in the areas of Wissler’s Run and the 

powerhouse and then extends east, and continues to parallel the river for another roughly 

5,000 feet. The project boundary extends west across the Susquehanna River 

encompassing the transmission lines for about 4.5 miles to PBAPS. 

Exelon has classified land use throughout the project based on its primary use. 

Existing classifications include:

• Project Operation (425 acres) – Lands used for power generation and 

electric transmission/distribution infrastructure and purposes;

• Developed Recreation (667 acres) – Lands managed for developed public 

recreation facilities and activities. This includes commercial recreation 

facilities.

• Public Access Lands (701 acres) – Lands generally open to the public but 

that are managed by a federal, state, county, or conservation entity. 

Exelon has an SMP for the Muddy Run Project to manage shoreline resources 

through the following programs and policies: shoreline erosion control; general 

maintenance; woody debris management; game species management; sensitive natural 
265

resource projection overlays and policies; leased premises policy; and a policy restricting 

certain recreational uses. No lands of the United States are within the project boundary.

Conowingo Project

The Conowingo Project is located in Pennsylvania and Maryland. The northern

8 miles lie within Lancaster and York counties, Pennsylvania, while Conowingo dam and 

the southern 5 miles within the project boundary are within Cecil and Harford counties, 

Maryland. The Conowingo Project boundary extends approximately 14 miles upstream 

from Conowingo dam to the lower end of the Holtwood Project tailrace. The project 

boundary crosses the river just below Holtwood Road (Route 372) at the Norman Wood 

Bridge on the western shoreline, to approximately 0.5-mile south of the bridge on the 

eastern shoreline. The project boundary extends 2.5 miles downstream of Conowingo 

dam along the west bank of the river and 0.5 mile downstream along the east bank of the 

river. No lands of the United States are within the project boundary.

The Conowingo Project encompasses 11,721 acres: 9,951 acres of flowed land 

and 1,770 acres above the normal high water elevation. The land in and around the 

project boundary is mostly rural, consisting primarily of agriculture fields and forested 

lands. 

Exelon leases more than 420 lots on project lands for seasonal residential cottage 

use. The leases stipulate that the cottages must remain shuttered from November through 

March 1. In addition to complying with all environmental regulations, zoning standards, 

and building codes, the cottage leases include a uniform set of standards that address the

size, materials, and floatation materials used in dock construction as well as erosion 

control, vegetation removal, wastewater disposal, shoreline development, and cultural 

resource protection. Residents cannot dig wells, install septic systems, or expand homes 

without permission from the county and Exelon. It is Exelon’s current policy not to 

create any new cottage lease lots within the project boundary and that any leases for 

existing cottages that are abandoned or become damaged and are not replaced by 

structures conforming to all applicable regulations will be terminated. All structures and 

improvements will be removed from the leased lot, the land will be restored to a natural 

condition, and the site will be precluded from future cottage leases. 

3.3.5.2 Environmental Effects

Recreation Management 

York Haven Project

York Haven Power proposes to maintain the existing public recreation facilities at 

the York Haven Power Plant Recreation Area (including the canoe portage trail), Battery 

Island Picnic Area, Goodling Island Picnic Area, Shelley Island Recreation Area, 

Goosehorn Island Picnic Area, and the East Shore Boat Launch and Canal Lock to ensure 

continued public use and enjoyment of project lands and waters through a future license. 
266

York Haven Power does not propose any improvements to these project recreation sites. 

York Haven Power also does not propose a recreation management plan; however, it 

proposes to consult with the Pennsylvania DEP, Pennsylvania DCNR, SRBC, and 

Pennsylvania FBC to consider the recreation resources and management strategies at the 

York Haven Project 10 years after the effective date of a future license. The review 

would take into consideration the recreation facilities, use levels, and operation and 

maintenance of both York Haven Power project facilities, as well as private and 

commercial facilities at the project. York Haven Power suggests it would conduct a 

recreation study if such information would be helpful in the consultation process. 

The adequacy and condition of existing recreation facilities and access at the York 

Haven Project, including the ease of portaging and the potential for additional recreation 

facilities, was raised as a concern during project scoping. Specifically, Pennsylvania 

FBC recommended improvements to non-motorized watercraft portages at the project so 

that boaters would not have to notify York Haven Power in advance for assistance. 

Our Analysis

York Haven proposes a number of operational and maintenance activities related 

to recreation, such as allowing anglers to fish the project’s catwalk, maintaining public 

boat access areas, consulting on the recreation resources 10 years after license issuance, 

and complying with FERC Form 80 reporting requirements. York Haven Power does 

not, however, include a plan for implementing these measures or investigating whether or 

not the sites are meeting the demand over the course of a license. Developing a formal 

recreation management plan would provide a more cohesive guide for the protection, 

mitigation, and enhancement of these resources. Effective recreation management plans 

ensure that the project adequately provides for the recreation needs of the area. An 

effective plan would include procedures to consult with the Pennsylvania FBC, 

Pennsylvania DNR, and Pennsylvania Game Commission over the course of any license. 

Comprehensive recreation management plans would include summaries of the facilities 

and uses, current and future visitation estimates, and formal monitoring plans every 

10 years as proposed by York Haven Power to ensure the sites meet the demand. 

There are currently no known issues of crowding, overutilization, unsafe 

conditions, or general issues that compromise recreation use, access, and enjoyment of 

the York Haven Project lands and waters. Retrieval of river rocks for the proposed

nature-like fishway would require the use of heavy machinery driving back and forth 

downstream of the main dam to collect and deliver the large boulders in an area popular 

with anglers, kayakers, and general exploration of the rocks. York Haven Power does not 

propose any specific measures to protect human safety during this process. Development 

of measures to allow recreation and extraction and transport activities to coexist during 

construction of the fishway would ensure visitor safety is considered. Including those 

measures in a formalized recreation management plan would further ensure all recreation 

resources are considered, operated, and maintained for the duration of any license. 
267

Muddy Run and Conowingo Projects

Exelon proposes to implement Recreation Management Plans for both the Muddy 

Run and Conowingo projects. The plans address recreation resources, including: 

recreation facilities that are located within the FERC project boundary, are owned and 

managed by Exelon, and are on lands owned in fee title by Exelon. The plans would 

address maintenance and capital improvements to ensure continued public use and 

enjoyment of project lands and waters through a future license. The three recreation 

areas addressed by the proposed Recreation Management Plan at the Muddy Run Project 

include: Muddy Run Park and Campground, Muddy Run WMA, and Wissler’s Run 

Park. The 15 recreation sites addressed by the proposed Recreation Management Plan for 

the Conowingo Project include: Lock 13, Lock 15, Muddy Creek Boat Launch, Cold 

Cabin Boat Launch, Dorsey Park, Line Bridge, Broad Creek Public Landing, Glen Cove 

Marina, Conowingo Swimming Pool and Visitors Center, Peach Bottom Marina, 

Conowingo Creek Boat Launch, Funk’s Pond, Conowingo Dam Overlook, Fisherman’s 

Park/Shures Landing, and Octoraro Creek Access. Specific elements of the plans, such 

as facility improvements, operation and maintenance, monitoring, and plan updates, are 

addressed below in our analysis.

Recreational Facility Improvements and Rehabilitation

As part of the proposed Recreation Management Plans, Exelon would make 

capital improvements to two facilities at the Muddy Run Project and 13 facilities at the 

Conowingo Project. Proposed improvement projects would be implemented within the 

first year of license issuance. In addition, Exelon suggests it would pursue dredging as a 

means to maintain boater access at Peters, Conowingo, and Broad creeks. 

Exelon proposes to upgrade a variety of amenities within Muddy Run Park and

make repairs at Wissler’s Run Park near the Muddy Run powerhouse. As part of the 

improvements, Exelon would replace the existing boat launch facility at Recreation Lake 

with a new concrete plank ramp that includes a new gangway and floating dock (ADA 

compliant) and also make shoreline improvements to limit erosion. Exelon also proposes 

to upgrade the ADA picnic site, stabilize 150 feet of the shoreline at Recreation Lake 

between the ADA picnic site and the rental boat dock, convert the timber retaining wall 

to sheetpile retaining wall, upgrade service to 50-amp electrical service at 50 sites, 

expand the playground adding a tot lot, construct a spray park, and provide Wi-Fi service 

to park users. 

At Wissler's Run Park, Exelon proposes improvements that include removing the 

non-functioning fish cleaning station, rebuilding and repaving the existing walkway 

along the top of the bank, and designating two parking spaces near the picnicking

pavilion as meeting ADA standards. The walkway from the parking area to the picnic 

area and the parking lot were both repaved in 2011.

As part of the plan, Exelon also proposes to erect and maintain FERC Part 8 signs 

at River Road and Furniss Road Muddy Run WMA parking areas. Exelon proposes to 
268

continue to lease these lands to Pennsylvania Game Commission for the term of a future 

license. 

The State of Maryland agrees that Exelon’s proposed improvements to existing 

recreation facilities would enhance recreation use at the projects; however, it 

recommends additional measures, such as providing additional facilities for bird watchers 

and more hiking trails. 

A number of individuals commented that the biggest issue at Peach Bottom 

Marina is that the harbor and river just outside of the railroad bridge are so badly silted in 

that boats cannot access the marina at normal low or even medium water levels.

Exelon proposes to upgrade and improve 13 existing recreation facilities at the 

Conowingo Project. The proposed recreation enhancements include:

• adding fencing and vegetation removal at Lock 13;

• new restrooms, dock, and parking enhancements at Lock 15;

• boat launch enhancements at Muddy Creek;

• parking, picnic area, and boat ramp upgrades at Cold Cabin;

• restroom and boat ramp upgrades at Dorsey Park;

• creek stabilization at Conowingo Creek;

• parking and wall improvements at Glen Cove Marina;

• improved signage at Funk’s Pond;

• providing ADA improvements at Conowingo Pond;

• upgrading pavilion, picnic area, fence and parking at Overlook;

• providing improvements to the boat ramp at Fisherman’s Park;

• bank stabilization at Line Bridge; and

• providing shore access at Peach Bottom.

Recreation Facility Operation and Maintenance

As part of the proposed Recreation Management Plans, Exelon would maintain the 

existing and proposed recreation facilities as described in the plan for the term of a FERC 

license. Exelon, at its discretion, may also restrict use and access to (or close) a site, or 

any portion thereof, on a short-term basis for maintenance/construction activities, unsafe 

conditions, emergencies, and operational reasons. At the Conowingo Project, Exelon 

also proposes a number of programs and measures to meet safety objectives including: 

water release safety devices, upstream boat buoys and warning signs, flow information, a 

canoe portage shuttle, boat launch channel markers, security fencing/warning signs, 

maintaining water levels during the boating season, and general facility maintenance. 
269

Exelon states that, should additional project facilities be developed over the term of the 

FERC license, it would be receptive to partnering with interested parties for the 

development, operation, and management of such facilities. Exelon would ensure that 

project facilities, existing and future, that are managed and operated by third parties, 

would be managed and operated in accordance with FERC rules and regulations and any 

license articles.

Recreation Monitoring Program

As part of the Recreation Management Plans, Exelon proposes to use the FERC 

Form 80 Licensed Hydropower Development Recreation Use Report to assess and report 

recreation use and capacity every 6 years. Exelon states this level of monitoring would 

provide a comparison with the recreation use projections provided in the Recreation 

Management Plans to help determine if additional recreation facilities are warranted 

during the license period.

Our Analysis

Exelon (2012a and 2012b) concludes that, although visitors indicated high 

satisfaction with the facilities, many of the recreation sites managed by Exelon exhibited 

deferred maintenance (e.g., boat ramp upgrades, parking resurfacing) or a complete lack 

of highly desired amenities, such as restrooms. The lack of restrooms or restrooms in 

disrepair could pose potential health risks if visitors are forced elsewhere. Broken 

amenities, amenities in a state of disrepair, or amenities in need of routine maintenance 

also provide unsafe and uninviting conditions that diminish the quality of the recreation 

experience and resources. Implementation of the proposed Recreation Management 

Plans and the specific enhancements would provide a framework to guide the 

management of recreational resources to ensure that these sites receive updated 

amenities.

As currently proposed, the plans for the Muddy Run and Conowingo projects put 

an increased emphasis on facility improvements, especially boater access and parking, 

and restrooms. Overall, 96 percent of survey respondents rated the facilities at Muddy 

Run Park as ‘good’ or ‘excellent.’ The comment received most frequently (27 percent)

was that a swimming pool within the park or a roped-off swimming area at the recreation 

reservoir was desired by visitors. Construction of Exelon’s proposed spray park would 

provide the body-contact recreation visitors requested while preserving the no-swimming 

policy at Recreation Lake. 

Improvements to the Recreation Lake boat ramp, ADA picnic area, shoreline and 

retaining walls would improve boater access and maintain water quality by reducing 

erosion from these areas. Improvements to the ramp would enhance boater access; a 

popular activity on the lake. Similarly, improvements to the campground electrical 

service, such as more 50-amp service campgrounds and Wi-Fi, would address modern 
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camper needs such as increased use of electronic devices (e.g., recreational vehicles with 

air conditioning, personal computers, smart phone charging). 

Removal of the non-functioning fish cleaning station at Wissler’s Park would 

eliminate the temptation for users to clean fish on site and leave the waste, which could 

negatively impact the aesthetics of the area. Enhancements to the pathway and 

designating two additional parking areas ADA would improve the overall recreation 

resources at the site.

As licensee, Exelon is responsible for providing reasonable public access to 

project lands and waters. Through the proposed Recreation Management Plans, Exelon 

recognizes the importance the two projects play in providing recreation in the region and 

acknowledge that the recreation facilities will be maintained for the duration of any 

license. However, the plans are limited in scope by failing to identify specifics of any 

monitoring programs to ensure the sites are meeting demand throughout any license other 

than through the FERC Form 80 process. 

The FERC Form 80 is useful to analyze overall use levels and project-wide 

capacity; however, it provides broad, rather than site-specific, recreation information. 

Development of a monitoring program that includes input from users that mimics the 

methods used during the relicensing studies would enable Exelon to meet its stated goal 

of comparing recreation data, by site, with future use estimates, as described in the 

Recreation Management Plans. As required now, the FERC Form 80 reports annual use 

estimates for the entire project, while Exelon is proposing a strategy that looks more 

closely at recreation use levels at each site. Including the methods of this monitoring 

effort in revised Recreation Management Plans for both projects would ensure the proper 

data collection to guarantee all the facilities are meeting the demand. Visitation rates can 

change dramatically year to year and through time; however, given the proposed facility 

enhancements, conducting a recreation use study every 12 years, consistent with every 

other FERC Form 80 reporting deadline throughout the license term, would ensure the 

proposed plans are current and the sites are meeting the demand.

Similarly, Exelon does not include provisions to update the plans. Since the 

projects were first constructed, recreation demand for water-based recreation has steadily 

grown. Over time, the facilities have aged, and as documented in the recreation reports, 

they exhibit wear and tear associated with regular use. Addressing maintenance of the 

recreation facilities is an important component of a recreation management plan. 

Recreation is not static and ensuring that facilities are the right type for the demands over 

the term of a typical license requires monitoring to ensure the proposed Recreation 

Management Plans are revised to prevent any drop off in the quality of the resource. A 

revised recreation management plan that includes scheduled updates coordinated around 

a recreation use study could capitalize on the timing and information to address any 

changes in recreation resources that may be necessary in the middle of any license term. 

Having a scheduled update ensures the plan is kept current regardless of the extent of 

changes between plans. Development of the recreation use monitoring methods in 
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consultation with interested agencies and stakeholders would ensure sites and uses are 

monitored to guarantee the recreation management plan remains current and includes

appropriate diversity in recreation resources.

Exelon’s proposed boat ramp and boat launch enhancements at existing recreation 

facilities would provide significant improvements to the project’s recreational resources. 

Implementation of the proposed Sediment Management Plan, as discussed in section 

3.3.1, Geology and Soils, would include monitoring the water depth at Peter’s Creek 

(Peach Bottom Marina), Conowingo Creek, and Broad Creek (Harford County boat 

launch) every 5 years; however, the plan stops short of identifying at what depths the 

locations need to be dredged and scheduling dredging. These three boat ramps represent 

half of the boat ramps providing access to Conowingo Pond for motorized boating. 

Visitor survey results indicate that 6 percent of the comments received at Conowingo 

Creek targeted shallow water/dredging needs; however, because Exelon maintains the 

minimum pond elevation at 107.2 feet on weekends between Memorial Day and Labor 

Day, boaters may not perceive a need for dredging at most sites. Maintaining the 

minimum pond elevations as currently required would ensure the boating resources are 

maintained through the term of any license.

At Broad Creek Public Landing, the two most common comments received were 

the need for an improved boat ramp (29 percent) and higher water levels (14 percent) as 

mentioned by those fishing in the spring and summer. Stakeholders consulted in 

development of the Recreation Management Plan expressed dissatisfaction with the water 

depths and amount of siltation at Peach Bottom Marina. Because this is the only marina 

with gas on the Pennsylvania side of the river, siltation of the marina compromises 

boater’s ability to access the marina and weakens the businesses’ ability to operate. 

Exelon reported that the depth of water at the toe of the Peach Bottom boat ramp was 

3 feet, meeting the States for Organizational Boating Access Design Handbook for 

Recreational Boating & Fishing Facilities recommended minimum water depth of 3 feet. 

Overall, Peach Bottom Marina received the smallest share of visitation to the Conowingo 

Project; however, it is not clear how much sedimentation of the marina or other factors 

played in the site receiving such low amounts of use. 

Exelon study results indicate the combination of pool elevation and sediment 

accumulation compromises motorboat launches from these sites under specific 

conditions. Cross referencing the bathymetric mapping proposed under the Sediment 

Management Plan at the three sites into the final Conowingo Recreation Management 

Plan would ensure bathymetric mapping sediment monitoring results are included in 

discussions related to boater access to the reservoir. Development of a final Sediment 

Management Plan that includes detailed benchmarks for dredging, a schedule, and 

commitment to dredging the three access areas as soon as the benchmark water depths are 

reached would ensure that recreation access is not lost or compromised indefinitely. 
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Reopening Catwalk on Conowingo Dam

Not included as part of the proposed Conowingo Recreation Management Plan is 

the continued closure of the catwalk on the downstream face of Conowingo dam. The 

catwalk is a narrow, steel and reinforced concrete extension walkway attached to the 

exterior of the powerhouse wall. The catwalk spans 820 feet along the length of the 

powerhouse. 

The catwalk was very popular with anglers prior to its closure after the events of 

September 11, 2001. On May 1, 2007, the Director of the Office of Energy Projects 

issued an Order Amending Exhibit R (119 ¶ FERC 62,088) removing the catwalk as a 

project recreation facility. The order authorized new recreation facilities at Fisherman’s 

Park on the west side of the river, which now provides anglers the only opportunity to 

fish just below the dam (the Fisherman’s Wharf). This order also authorized public 

fishing access along the north and south banks of Octoraro Creek on the east side of the 

river. Exelon completed construction of the Octoraro Creek facility in May 2008 and 

completed the Fisherman’s Park/Wharf in 2009. Fishing is allowed along the shoreline 

of the park (about 700 yards) except for an area within 100 yards of Conowingo dam.

Exelon evaluated closing of the catwalk to recreational fishing and concluded that

while reopening the catwalk is physically feasible, opportunities at the project are 

sufficient to meet existing and reasonably projected demand without the catwalk. Exelon 

further questions the benefit gained by investing in security upgrades prior to opening the 

catwalk.

The State of Maryland disagrees with Exelon's proposal to keep the powerhouse 

catwalk closed to the public, and believes the new fishing pier does not mitigate for the 

loss of the catwalk. About a half dozen private citizens also recommend that Exelon 

reopen the catwalk because it provides a better angling experience. 

Private anglers also recommend that Exelon expand the operating hours of 

Fisherman’s Park/Wharf so as to be open between 4 a.m. to midnight. The comments 

received indicate the current policy of dawn to dusk limits the hours for boating access 

downstream of Conowingo dam because anglers would prefer to launch early in order to 

get lines in the water before sunrise when light changes drastically. Similarly, anglers 

would appreciate launching in the evening and being able to stay on the water later into 

the night to take advantage of feeding times around the changing light. According to the 

comment letters, striped bass, a popular game fish residing in the tailwater, feed closest to 

the surface and shore during these predawn and post dusk times. 
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Our Analysis

Reopening the catwalk would provide access to a historically popular angler 

opportunity. Fishing from the catwalk offers a different opportunity and experience than 

fishing from the shoreline, allowing anglers to cast with the river flow and directly into 

the middle of the channel. Seasonally, this can be advantageous depending on the fish 

run(s) because some species are more likely to be caught from the middle of the channel 

than from the bank (casts from the bank are pushed to the sides of the channel by 

the flow). 

Since Exelon closed the catwalk in October 2001, it constructed a new fisherman’s 

platform along the west bank of the shoreline and developed new trail access to the river 

on the east bank at Octoraro Creek. The Fisherman’s Wharf provides ADA-compliant

ramps and a concrete platform above the shoreline for anglers, while Octoraro Creek 

provides parking and a trail to the shore along the creek. Although neither provides 

anglers a chance to fish the main channel in a way that was similar to fishing from the 

catwalk, the enhancements do provide additional opportunities for this reach of the 

project. A third site, the Lower Susquehanna Greenway, provides shoreline access 

between the Fisherman’s Park and Deer Creek. Exelon estimates that Fisherman’s Park 

and Octoraro Creek receive the greatest percent of shoreline fishing activity downstream. 

Exelon estimates a reopened catwalk could support 150 anglers at one time. Exelon 

projections show the existing access below capacity out to year 2050; however, the 

estimates are based on general recreation trends and are not specific to unique features 

like the catwalk or tailraces of dams like at Conowingo. 

Upstream of Conowingo, angling on the downstream faces of dams is popular on 

the catwalks at the York Haven and Safe Harbor projects. York Haven Power can close 

the site with a single chain-link fence gate. Access is provided in proximity to both the

sluice gate and the base of the powerhouse wall. Similarly, anglers at Safe Harbor are 

afforded access directly below the powerhouse; however, they must pass a security guard 

station prior to gaining access to fish. Additionally, Corps’ lock and dam systems that 

also produce power often provide similar fishing opportunities in the tailrace below the 

powerhouses.

Exelon security experts recommend a number of improvements to the catwalk 

before considering reopening, including measures that deter, detect, and assess any 

unwanted activity; delay escape; respond to a threat; and harden the physical structure. 

If Exelon were to reopen the catwalk to provide better angler access to the middle 

of the channel, it could implement select security measures that were identified as 

appropriate in its catwalk study report for addressing security risks at the catwalk 

(Security Management Solutions, 2012). Security measures, such as installing a new 

security guard station, checking anglers in and out, and operating on a limited basis, 

could provide angler opportunities while minimizing any potential security risks Exelon 

has reservations about public use of the catwalk. Limited operation of a reopened 

catwalk could follow specific fish species open seasons when use would be expected to 
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be highest. On-line discussion forums warn anglers that fishing the shoreline 

downstream of Conowingo dam can be shoulder to shoulder during certain seasons with 

multiple anglers, indicating the shoreline immediately downstream of the dam is crowded 

(Stripers Online, 2014). Given the relative proximity of the dam to the large metropolitan 

areas of Baltimore, Maryland, and Wilmington, Delaware, reopening the catwalk would 

enhance the angling resources by providing access to a historically popular site and a 

different opportunity than is currently available.

Debris Management

Debris accumulation, removal, and passing are part of operating a hydroelectric 

project. The presence of debris in project reservoirs can present safety and aesthetic 

hazards; however, the dynamic nature of the volume and timing of debris within any 

reservoir at any given time makes managing it dynamic as well. The removal and/or 

passing of debris that has accumulated in front of the trashracks is an important 

component of operating hydroelectric projects of any size. Given the size of the lower 

Susquehanna River watershed, the amount of debris arriving and passing these projects 

can be significant. 

York Haven Project

York Haven Power estimates the project traps an estimated 5,000 cubic yards of 

debris in the powerhouse trashracks annually. It states that almost all of the debris arrives 

at the project during high-flow events when river flows far exceed the hydraulic capacity 

of the project. In those conditions, much of that debris passes over the main dam. Nonnatural debris that accumulates in the forebay is removed, and the remaining debris is 

sluiced downstream through a gated opening in the masonry non-overflow wall at the 

downstream end of the forebay. Prior to opening the sluice gate, York Haven Power 

notifies PPL’s Brunner Island Station that debris is to be sluiced. 

In 2010, York Haven Power and Pennsylvania DEP reached an agreement that is 

reflected in the project’s current NPDES permit and in section 3.3 of the Settlement 

Agreement, providing for an annual payment of $25,000 to the York County 

Conservation District to finance debris removal in the Lower Susquehanna River 

Watershed. The Settlement Agreement requires York Haven Power to continue its 

current debris management practices, including prior notice to PPL's Brunner Island 

Station when debris is to be sluiced (absent extraordinary or emergency conditions).

Conowingo Project

During the initial scoping meeting held on the evening of June 11, 2009, the 

Lower Susquehanna Riverkeeper expressed concern that debris passing the Conowingo 

dam under high-flow conditions often gets deposited in the Sassafras River, causing 

damage and expense for cleanup to those living along the river. The Sassafras River is 

located in Maryland, approximately 10 miles downstream of the mouth of the 

Susquehanna River at the head of Chesapeake Bay on the east side of the bay. The 
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conditions described by the Riverkeeper were that the high flows entering Chesapeake 

Bay from the Susquehanna River cause a backwater flow up the Sassafras River, such 

that instead of the debris passing out through Chesapeake Bay, some of it gets trapped in 

the Sassafras River. 

Debris is removed from the Conowingo powerhouse intakes using gantry cranes 

with grapple attachments. Debris removal occurs during low and normal flow conditions, 

but cannot take place during high river flows due to safety concerns. The methods and 

practices employed at Conowingo are comparable to methods employed at the York 

Haven, Safe Harbor, and Holtwood dams.

The amount of natural and human-made debris reaching Conowingo dam 

fluctuates from year to year. Between 1989 and 2011, (for years Exelon removed debris), 

Exelon estimates between 60 and more than 4,000 cubic yards have been removed on an 

annual basis. Exelon states some of the debris build-up can be as deep as 75 feet under 

the water surface in front of the dam. All debris removed is taken to Hopkinton Cove 

where it is separated and sorted as organic, tires, plastic, trash, or metal. Organic 

(natural) debris is recycled and ground up for mulch. All other debris is sent to a 

disposal/recycling facility or landfill.

Exelon also sponsors community-based clean-up events for the shoreline upstream 

and downstream of the dam, such as the Exelon Clean-up Day, clean-up of the 

Conowingo Creek boat launch, and the Lower Susquehanna Greenway River Sweep.

Based on the results of Exelon’s Debris Management Study (URS and Gomez and 

Sullivan, 2012c), Exelon determined that no additional practices were needed. None of 

the stakeholders recommended additional measures pertaining to debris management at 

Conowingo.

We discuss the aesthetics of the debris in section 3.3.7, Aesthetic Resources.

Our Analysis

A 2012 report on debris management (URS and Gomez and Sullivan, 2012c) 

identified quantities of debris passed and removed from the river at York Haven, Safe 

Harbor, Holtwood, and Conowingo dams; analyzed flow conditions that result in debris 

being passed naturally at the dams; and reviewed debris management methods and 

practices employed at the four dams.

Debris typically gets trapped at the dams when river flows are less than the 

hydraulic capacity of each project powerhouse, and are typically passed naturally over or 

through the dams when flows exceed the hydraulic capacity of the powerhouses in March 

and April. Since the hydraulic capacities of the four projects differ significantly (York

Haven – 17,000 cfs; Safe Harbor – 110,000 cfs; Holtwood – 31,500 cfs; and 

Conowingo – 86,000 cfs), debris is passed naturally under different hydrologic 

conditions. Debris would only be passed downstream from Safe Harbor when inflows 

exceed 110,000 cfs. Similarly, debris is only passed at Conowingo when inflows exceed 

86,000 cfs. 
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York Haven Project

Formalizing debris management at the York Haven Project as detailed in the 

Settlement Agreement would ensure debris does not pose long-term hazards to people 

and project operation. Notification of PPL’s Brunner Island steam plant would be a 

continuation of the courtesy York Haven Power provides so as to allow PPL opportunity 

to plan or prepare for any inconvenience from passing debris. 

Conowingo Project

As noted by the Lower Susquehanna Riverkeeper, debris is primarily deposited in 

the Sassafras River under high-flow conditions, when backwater effects on Chesapeake 

Bay flow upstream into the Sassafras River. When river flows are between 86,000 and 

110,000 cfs, debris is passed naturally at Conowingo dam from upstream in the 

watershed between Safe Harbor dam and Conowingo dam. When river flows exceed 

110,000 cfs, debris from the entire Susquehanna watershed can be passed downstream of 

Conowingo. Under these conditions, the natural passage of debris is beyond the control 

of the Conowingo Project.

Debris management practices employed at the Conowingo Project are consistent 

with BMPs and practices at the other dams upstream of Conowingo. Current practices 

remove up to several thousands of cubic yards of debris each year. 

Effects of Proposed Shoreline Management Plans

York Haven Power is not proposing an SMP as part of its final license application; 

however, it is proposing to continue to implement its shoreline leases of residential lots. 

York Haven Power would maintain the recreation lot lease program at the project (total 

of 288 leases) but indicates that it would terminate any leases when lots are abandoned by 

the lessee or when existing structures are damaged and not replaced by structures that 

meet current regulations.

As part of York Haven Power’s lease agreement, renters may have non-permanent 

structures within an 8-foot by 32-foot area; however, as noted during the environmental 

site visit May 21, 2013, many lots have substantial additions of a more permanent nature. 

Lots can be handed down from generation to generation; however, once the chain stops 

or the structures are more than 50 percent damaged or destroyed, the lot is eliminated 

from the rental program. This allows York Haven Power to slowly reduce the number of 

lots for rent over time. 

As part of its final license applications, Exelon proposes to implement the SMPs 

filed in August 2012 for both the Muddy Run and Conowingo projects. The SMPs

provide the framework for Exelon to manage the environmental and recreational 

resources within the project. Measures in the SMPs include General Maintenance, 

Shoreline Erosion Control, Erosion and Remediation Policy, Woody Debris 

Management, Non-Project Use of Project Lands, Shoreline Vegetation Management, 

Viewsheds, Access Trails, and Sensitive Natural Resource Protection Overlays and 
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Policies. Other land management-related policies include an HPMP (see section 3.3.6, 

Cultural Resources), Conowingo Island Public Use Policy, and Leased Premises Policy 

for Cottages. Exelon also proposes to amend the SMP as the facts and circumstances 

may warrant. 

The project land classifications used to define allowable uses are similar for both 

Muddy Run and Conowingo. Land classifications at Muddy Run include: (1) Project 

Operations, which identifies project lands used for generation and transmission facilities; 

(2) Developed Recreation, which identifies lands managed for public recreation facilities 

(including commercial facilities) and activities; and (3) Public Access lands, which 

identifies lands managed by federal, state, county, or conservation organizations under 

agreement with Exelon, whereby public access and use of the lands is allowed according 

to the rules of the managing entity (these lands are typically unimproved).

The land classifications at the Conowingo Project include the same classifications 

as Muddy Run and also include the following three classifications: 

(1) Natural/Undeveloped, which identifies lands that are primarily undeveloped and 

available for public access and use; (2) Industrial and Other non-project lands, which 

identify lands managed for industrial/commercial uses and other non-project uses 

including shoreline stabilization projects; and (3) Cottage Lands, which identifies lands 

leased to individuals for seasonal use. 

The proposed leased premises policies address both private cottage lots, and public 

(state, county, or local agencies), or commercial vendors for the development of 

recreation related structures and facilities. Cottage lessees are required to comply with all 

applicable local, state, and federal laws for the development and use of the land, as well 

as the Exelon-imposed land use rules. Exelon rules and regulations for cottages address 

such issues as construction permits, lease transfers, erosion control, vegetation removal, 

water connections, wastewater disposal, shoreline development (e.g., piers, docks, 

boathouse, bulkhead, retaining wall), and cultural resource protection. In 2012, Exelon 

added language to the Conowingo lease documents that the “tenant must provide 

certification that all sanitary and gray water systems are in good working order in 

accordance w/applicable regulations, and tenant is not in default under any sewage 

pumping agreement by a cert. vendor on or before Nov. 1 annually.” It is Exelon’s 

policy not to create any new cottage lease lots within the project boundaries. As existing 

cottages are abandoned or become damaged and are not replaced due to local zoning 

restrictions, leases would be terminated. In such cases, all structures and improvements 

would be removed from the leased lot, and the property would be restored to a natural 

condition and the site would be precluded from future cottage leases.

Leases for public recreation and access facilities must comply with Exelon’s 

“Rules and Regulations Governing the Use and Occupancy of Leased Premises,” which 

parallel those developed for the cottage leases. In addition, leases must use the properties 

for park and public recreation access and facilities must comply with applicable local, 

state, and federal regulations. 
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Interior makes a 10(a) recommendation that Exelon prepare and implement SMPs

in consultation with FWS that are consistent with Guidance for Shoreline Management 

Planning at Hydropower Projects (FERC, 2012). The SMPs shall include specific 

measures and policies related to shoreline vegetation management and erosion control, 

woody debris management, game species management, sensitive natural resource 

protection, recreation use, and use of project lands. The licensee shall adopt BMPs for 

controlling sediment introduction from lands within the project boundary.

The lack of a central septic system for the islands where York Haven Power issues

lease permits for residential lots was raised as a concern during project scoping. Each 

camp has some type of on-lot sewage disposal system; however, Pennsylvania FBC 

questions if this is an adequate, ecologically sound system for the island environment.

Our Analysis

York Haven Project

York Haven Power does not have a comprehensive shoreline permitting program; 

however, it does permit non-project uses via the existing standard land use article and 

shoreline permits for recreational lots. Implementation of York Haven Power’s cottage 

lease agreements would continue to allow private use of portions of the islands and 

shoreline around Lake Fredric. York Haven Power suggests that routine monitoring 

would occur to ensure that cottages in disrepair are taken out of the program; however, 

the amount and type of monitoring of structures (e.g., conditions or encroachments) is not 

clearly described in the license application. Without a transparent process it is not clear 

what methods or interval York Haven Power uses to make findings to terminate leases 

and reclaim the lot area. 

York Haven’s policies implemented in 2010 prohibiting the use of water 

withdrawn from wells or the river should reduce the amount of wastewater being 

produced at the cottages because residents must now provide their own supply of bottled, 

potable water. According to York Haven Power, many of the lots are expected to use 

substandard sewage disposal systems. Lease agreements make it clear that leaseholders 

are responsible to undertake and complete any sewage system upgrades or replacements 

required to comply with the Pennsylvania Sewage Facilities Act and related rules and/or 

the Londonderry Township On-Lot Disposal System ordinance. 

Although we have no reason to conclude that county and local agencies 

responsible for monitoring and issuing on-lot disposal system permits would allow 

systems to continue in an environmentally irresponsible manner, the ultimate 

responsibility for project land and the protection of associated water quality and 

recreation resources at Lake Fredric lies with York Haven Power. The Commission has 

no authority over the county or local agencies, and York Haven Power has an ongoing 

responsibility to supervise and control shoreline developments to ensure that they are not 

inconsistent with project purposes, including protection and enhancement of the project’s 

scenic, recreational, and environmental values. 
279

The Commission recognizes the need to consider multiple resource concerns and 

interests in the development of a comprehensive plan to manage the shoreline, and the 

need to involve interested parties in the development process. The lot lease agreements 

only address some of the resource values at the York Haven Project. Licensees have a 

responsibility to ensure that shoreline development activities that occur within a project 

boundary are consistent with project license requirements, purposes, and operation. A 

well prepared SMP can assist the licensee in meeting its responsibilities throughout the 

term of any license. While these plans are specific to a particular project, SMPs should 

generally contain a summary of the purpose, goals and objectives of the plan and a 

description of the shoreline use classifications, which identifies allowable and prohibited 

uses for existing and future use of the shoreline. A plan may have multiple classification 

or sub-classification types, but they usually fall within three general types: (1) a 

protected or natural resource preservation classification, (2) a limited development 

classification, and (3) a more intensive development classification. SMPs should also 

include: (a) maps showing the shoreline classifications in relation to the project 

reservoir, project boundary, and various other features; (b) a permitting program and 

guidelines developed by the licensee; (c) a monitoring and enforcement program; and 

(d) provisions for periodic review and update of the plan. Development and 

implementation of a comprehensive SMP in accordance with the Commission’s 

published guidelines (FERC, 2012), and submitted for Commission review and approval, 

would ensure the shorelines are managed for the scenic, recreational, and environmental 

values for the duration of any future license. 

Muddy Run and Conowingo Projects

Implementation of Exelon’s proposed SMPs would provide a single source for 

shoreline management guidelines, policies, and an overall framework for managing the 

Muddy Run and Conowingo shorelines over the terms of any new licenses. Currently, 

cottage lots are managed with multiple policies and agreements, such as lot leases and 

erosion control permits. These documents do not, however, identify sensitive shoreline 

resources, public access areas, enforcement measures, or provisions for periodic review 

and updates. The proposed plans would bring all existing shoreline management 

programs and activities, such as the current residential lot and cottage lease program, and 

any other guidelines, into a single, comprehensive document. 

Implementation of the land classification and shoreline management policies 

would provide for the management of land uses within the project boundaries. Project

lands would remain available for public recreational uses, and private and commercial 

uses would continue to be allowed on project lands pending proper reviews. Exelon 

would review permit applications for activities such as improvements to leased cottages, 

construction of boat docks, piers, and landscaping, and would ensure that all residential 

cottages sewage systems meet local standards on an annual basis.

The proposed SMPs provide Exelon an opportunity to amend the plans as facts 

dictate; however, the plans do not include routine monitoring or consultation to verify the 
280

conditions that may warrant changing the plans. A monitoring and review process would 

inform Exelon and other interested parties if changes to the SMPs are necessary through 

the term of any license. Consultation with the appropriate agencies and other 

stakeholders as part of periodic review would ensure that multiple interests and needs are 

addressed. Preparation of revised SMPs that includes regular consultation with interested 

stakeholders would ensure the plan is consistent with conditions at the projects.

Erosion has occurred along various segments of Muddy Run and Conowingo 

shorelines as discussed in section 3.3.1, Geology and Soils. Exelon does not propose any 

changes to project operations that would affect existing erosion rates. However, because 

wind and wave action are likely to continue, erosion issues are likely to persist.

Effects of Changes to Project Boundary

York Haven Power proposes to add 1.9 acres to the total project boundary acreage 

to encompass the project’s East Shore Boat Launch and Canal Lock recreation area. The 

proposed boundary modification would include the recreation site completely within the 

project boundary. The lands proposed to be added to the project are all owned in fee by 

York Haven Power and are outside the 30-foot setback from the centerline of the adjacent 

railroad line that constrains the project boundary on both sides of the impoundment. 

Exelon proposes to remove 1,965 acres from the Conowingo Project boundary. A 

1,760-acre area would be removed from the east and west banks downstream of 

Conowingo dam as the existing project boundary extends to Havre de Grace. The 

proposed project boundary would extend from a point approximately 3,000 feet 

downstream of Conowingo dam on the western shoreline continuing downstream across 

the river to a point along Maryland State Route 222 (Susquehanna River Road), 

approximately 2,000 feet downstream of the confluence of Octoraro Creek and the 

Susquehanna River. The original area within the existing project boundary was 

necessary during construction of the project; however, since construction is completed, 

Exelon proposes the lands are no longer necessary for the operation and maintenance of 

the project. The boundary adjustment would remove four non-project recreation facilities 

from the project boundary, including portions of the Lower Susquehanna Heritage 

Greenway, Deer Creek Access, Lapidum Boat Launch, and McLhinney Park.

A 205-acre area would be removed near the Boy Scout dam on Broad Creek in 

Maryland. The area begins at a point about 1 mile downstream from the Route 623 

Bridge across Broad Creek and encompasses land along Broad Creek between this point 

and the Boy Scout dam. The area does not contain any existing project recreation 

facilities and is not necessary for operation and maintenance of the project.

Exelon would negotiate leases with recreation facility operators that would no 

longer exist in the project boundary, and would negotiate a new lease with Maryland 

DNR for continued operation of the Lower Susquehanna Greenway Trail and MasonDixon Trail on Exelon-owned lands.
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Lancaster County Conservancy commented that the landscape of the lower 

Susquehanna River has been designated a Pennsylvania Conservation Landscape (known 

as the Susquehanna Riverlands), and is part of the Susquehanna Gateway Heritage Area. 

The area (potentially) impacted by these projects includes a significant portion of the 

Captain John Smith Chesapeake National Historic Trail and part of the Mason-Dixon 

Trail.

Our Analysis

The addition of 1.9 acres of project lands at the York Haven Project would ensure 

the entire East Shore Boat Launch and Canal Lock recreation area is recognized as a 

project feature and managed under any future license for the project. Currently, the 

project boundary does not encompass the entire recreation area. These lands would be 

managed for their recreation resources consistent with the requirements of any license 

issued for the project. 

A relatively thin ribbon of land on the west bank downstream of Conowingo dam 

was included in past licenses so as to include the railroad that was used to shuttle material 

to the dam during construction. The old railroad is gone and lands in this area are now 

used for recreation; however, these lands serve no direct project purpose. Continuation 

of the lease agreements with the State of Maryland for Susquehanna State Park (which 

includes the Lower Susquehanna Heritage Greenway Trail, Deer Creek Access, and 

Lapidum Boat Launch) and the City of Havre de Grace for McLhinney Park would 

maintain recreation access at these locations if the project boundary were changed. With 

the exception of the Lower Susquehanna Greenway Heritage Trail, which connects 

Fisherman’s Park with Susquehanna State Park lands, the rest of these sites are nonproject recreation sites located more than 3 miles downstream of Conowingo dam. 

Removal of these lands would be consistent with FERC policy that only lands and waters 

needed for project purposes for the continued operation of the project should be included 

in the project boundary. Lands and waters needed may include those for (1) construction 

and operation of its project, and (2) to carry out other project purposes such as recreation, 

wildlife protection, and enhancement, etc. Execution of a new lease with Maryland DNR 

would ensure these lands are maintained for public recreation purposes; however, they 

would not be under FERC jurisdiction.

3.3.6 Cultural Resources 

3.3.6.1 Affected Environment

Section 106 of the NHPA requires the Commission to evaluate potential effects on 

properties listed or eligible for listing in the National Register prior to an undertaking. 

An undertaking means a project, activity, or program funded in whole, or in part, under 

the direct or indirect jurisdiction of a federal agency, including, among other things, 

processes requiring a federal permit, license, or approval. In this case, the undertakings 

are the relicensing of the Susquehanna River Projects. Potential effects associated with 

these undertakings include project-related effects associated with any new construction 
282

activities associated with the projects, and the day-to-day operation and maintenance of 

the projects.

Historic properties are defined as any district, site, building, structure, or object 

that is included in or eligible for inclusion in the National Register. Traditional cultural 

properties are a type of historic property eligible for the National Register because of 

their association with cultural practices or beliefs of a living community that: (1) are 

rooted in that community’s history or (2) are important in maintaining the continuing 

cultural identity of the community. In this EIS, we also use the term cultural resources to 

include properties that have not been evaluated for eligibility for listing in the National 

Register. In most cases, cultural resources less than 50 years old are not considered 

eligible for the National Register.

Section 106 also requires that the Commission seek concurrence with the 

Pennsylvania SHPO and Maryland SHPO on any finding involving effects or no effects 

on historic properties, and allow the Advisory Council an opportunity to comment on any 

finding of effects on historic properties. If Native American properties have been 

identified, section 106 also requires that the Commission consult with interested Native 

American tribes that might attach religious or cultural significance to such properties.

By letters dated May 11, 2009 (Muddy Run and Conowingo), and July 24, 2009 

(York Haven), the Commission designated Exelon and York Haven Power, respectively, 

as the Commission’s non-federal representatives for carrying out day-to-day consultation 

in regard to the relicensing efforts pursuant to section 106 of the NHPA. The 

Commission, however, remains ultimately responsible for all findings and determinations 

regarding project effects on any historic property, pursuant to section 106. 

Area of Potential Effects

Pursuant to section 106, the Commission must take into account whether any 

historic property within each project’s APE could be affected by the issuance of new 

licenses. According to the Advisory Council’s regulations, the APE is defined as “the 

geographic area or areas within which an undertaking may directly or indirectly cause 

alterations in the character or use of historic properties, if any such properties exist” 

(36 CFR 800.16[3]). The APE encompasses the likely extent of project operations and 

project-related environmental measures that could be undertaken during the term of any 

new licenses that are issued for the proposed projects.

In its application, York Haven Power defined the APE for the York Haven Project 

as the area within the project boundary as shown on the exhibit G maps provided in the 

application and includes all lands associated with York Haven dam and reservoir, the east 

channel dam, the powerhouse, transmission line, and associated project features. By 

letter dated April 26, 2010, the Pennsylvania SHPO concurred with this definition of the 

APE (letter from D.C. McLearen, Chief, Division of Archaeology and Protection, 

Pennsylvania Historic and Museum Commission, Bureau for Historic Preservation, 
283

Harrisburg, Pennsylvania, to D. Weaver, York Haven Power Company, York Haven, 

Pennsylvania, filed December 28, 2012).

In its application, Exelon proposed an APE for the Muddy Run Project that 

consists of all lands located within the project boundary as shown on the exhibit G maps 

provided in the application and includes all lands associated with Muddy Run dam and 

reservoir, the powerhouse, transmission line, and associated project features. In 

approving Exelon’s study plan dated December 22, 2009, the Commission also approved 

the project APE.

In its application, Exelon proposed a revised project boundary for the Conowingo 

Project that includes Conowingo dam and reservoir, powerhouse, transmission line, and 

associated project features but terminates just downstream from Conowingo dam. Exelon 

describes the APE as including all lands located within this proposed project boundary 

plus an additional 3.8 miles downstream to Spencer Island that are located in the current 

project boundary. While Exelon proposes to remove lands currently in the project 

boundary located downstream of Spencer Island from the current project boundary, it

stated that these lands would remain in the project APE because cultural resource sites 

could be affected by project-related flows in this area (personal communication between 

E. Carter [FERC], T. Sullivan, K. Smith, M. Hoover, and G. Lemay [Gomez and 

Sullivan]; B. Lynch and C. Hicks [Exelon]; and J. Ryan [VanNess Feldman], 

Washington, D.C., April 8, 2013). A narrow strip of land located in the current project 

boundary extending downstream from Spencer Island along the west side of the 

Susquehanna River to the city of Havre de Grace, Maryland, was excluded from the APE 

because Exelon did not identify any project effects in this area.

Cultural History Overview

The following discussion is adapted from the cultural overview provided in York 

Haven Power and Exelon’s license applications. 

The prehistory of the Susquehanna River Projects area can be divided into four 

general time periods: Paleoindian, Archaic, Woodland, and Protohistoric. Paleoindian 

peoples (12,000 – 7,500 B.C.) were nomadic hunter-gatherers who routinely used natural 

rockshelters as dwellings. Paleoindian sites are recognized by the presence of large 

fluted projectile points suitable for hunting large game present at the end of the 

Pleistocene. There are very few documented Paleoindian sites in the region, but one 

important site, Meadowcroft Rockshelter, is located in southwestern Pennsylvania. 

During the Archaic period (7,500 – 1,000 B.C.), people adapted to a warmer climate and 

increasingly relied on smaller game and abundant plant resources. These changes are 

reflected in changes in tool technologies to include smaller notched projectile points, 

groundstone tools, and steatite vessels. The Woodland period (1,000 B.C. – A.D. 1600) 

is marked by a transition to a more sedentary settlement pattern and the appearance of 

horticultural practices, elaborate ceramics, and increased ceremonialism evidenced by 

mound construction. The Susquehanna River Project areas primarily contain evidence of 

Archaic and Woodland period occupations, although one site believed to date to the 
284

Paleoindian period was identified within the York Haven APE. The final Prototohistoric 

period is characterized by profound changes in cultural practices as a result of contact 

with European explorers and settlers. Today, the Delaware Nation and the Onondaga

Nation of Native Americans retain ties to the Susquehanna River region.

European exploration of the Susquehanna River region began in 1608 when John 

Smith reached the mouth of the river. However, European settlements did not appear 

until the late 1600s when William Penn began to grant settlement rights in the region. 

Lancaster County was established in 1729 and subsequently divided into York, 

Cumberland, Dauphin, Lebanon, and Northumberland counties. The economy of the 

region was based primarily on mining, quarrying, milling, and agriculture, with tobacco 

being an important crop. The Colombia and Port Deposit Railroad was completed in the

middle 1930s, and the Susquehanna and Tidewater Canal was opened in 1840. These 

developments provided an important means of transport to the larger eastern cities.

The York Haven and Conowingo projects were two of four hydroelectric facilities 

built on the Lower Susquehanna River between 1904 and 1932. The York Haven Project 

Water and Power Company was incorporated in 1895 as a water supplier to York Haven 

residents and businesses. Construction of the project began in June 1901, and a 

powerhouse was designed by John Augustus Dempwolf using both utilitarian and 

Romanesque features. In March 1904, the structure was collapsed by an ice gorge and 

floodwaters, but repairs were completed by August of that same year. The powerhouse 

was expanded in 1907 to include additional generation capacity and new operating units 

went online in 1914. East channel dam was constructed in 1918. 

Conowingo dam was constructed between 1926 and 1928 to supply power to 

Philadelphia and southeastern Pennsylvania. The facility also provided power to railroad 

lines between Washington, D.C., and New York. In 1927, PECO Energy Company, 

Public Service Company of New Jersey, and PPL reached a cooperative agreement to 

interconnect their power systems through transmission lines to concentrate power in 

industrial areas of New Jersey and Pennsylvania. Construction of the Conowingo Project 

was a large endeavor, and required the relocation of the village of Conowingo and 

rerouting 16 miles of Pennsylvania Railroad track and Baltimore Pike. At the time of its 

construction, it was the second largest hydroelectric development in the United States. 

A license to construct the Muddy Run Project was issued to PECO Energy 

Company in September 1964. Construction of the project began that year, and the 

facility was in operation in 1967. At that time, it was the largest pumped storage facility 

in the world.

Prehistoric and Historic Archaeological Resources

York Haven Project

York Haven Power conducted research at the Pennsylvania Historical and 

Museum Commission and identified 24 previously recorded sites within the project APE 

and three areas that had been given “general site designations.” The three “general site 
285

designations” were attributed to Shelley Island (36DA3), Three Mile Island (36DA52), 

and Hill Island (36DA86) for their general cultural sensitivity but are not considered to be 

sites per se. In June 2010, an archaeological reconnaissance of the known sites within the

APE was undertaken (Stallings and Franz, 2011) to assess all known cultural sites in the 

APE for project-related effects. Of the 24 known sites, 17 are located on privately owned 

lands and were either not inspected or were surveyed by boat only. The remaining seven 

sites are located on lands owned by York Haven Power. None of the 24 sites have been 

formally evaluated for listing on the National Register, although 36DA99, 36DA100, 

36DA101, and 36DA235 were described as being potentially eligible. 

Muddy Run Project

Archival research conducted at the Pennsylvania Historical and Museum 

Commission enabled Exelon to identify three previously recorded sites within the Muddy 

Run Project APE (36LA67, 36LA103, 36LA368). Site 36LA67 is also located within the 

APE for the adjacent Conowingo Project. Phase IA archaeological studies also identified 

12 areas of archaeological sensitivity. These areas of interest (AOIs) and resulting field 

inspections were described in Phase IA Archaeological Study and Preliminary Historic 

Structures Assessment Report for the Muddy Run Pumped Storage Relicensing 

Application Project, Lancaster and York Counties, Pennsylvania (Sara et al., 2011a). 

Field inspections indicated that one of the previously recorded sites (36LA0103) is 

currently inundated by Muddy Run reservoir. Two AOIs (AOI 1, AOI 9) were identified 

as worthy of additional field research because they contained high localized erosion as 

well as moderate to high probability for archaeological resources. In its 

December 28, 2012, response to the Commission’s November 2, 2012, Additional 

Information Request, Exelon explained that both of these AOIs were located within the 

boundaries of a previously recorded site (36LA0067). These two AOIs were further 

investigated during Phase IB research with results presented in Phase IB Archaeological 

Survey of Two High Priority Areas of Interest (AOIs 1 and 9), Muddy Run Pumped 

Storage Relicensing Application Project, Lancaster and York Counties, Pennsylvania

(Sara et al., 2012a). A series of 19 shovel test pits was excavated in the two AOIs; no 

cultural materials were identified. The Pennsylvania SHPO agreed with Exelon’s 

Phase IB recommendations and stated that no further archaeological work at the two 

AOIs was required (letter from D.C. McClearen, Chief, Division of Archaeology and 

Protection, Pennsylvania Historical and Museum Commission, Bureau for Historic 

Preservation, Harrisburg, Pennsylvania, to C.E. Hicks, Exelon Corporation, Kennett 

Square, Pennsylvania, February 9, 2012). The third previously recorded site (36LA368) 

is situated above the shoreline and did not warrant further Phase IB investigations. No 

new archaeological resources were identified during Phase IA and Phase IB studies.

Conowingo Project

Archival research conducted at the Pennsylvania Historical and Museum 

Commission enabled Exelon to identify 37 previously recorded sites within the 

Conowingo Project APE. Phase IA studies also identified 45 areas of archaeological 
286

sensitivity. These AOIs and subsequent boat inspections of specific shoreline locations 

were described in Phase IA Archaeological Study and Preliminary Historic Structures 

Assessment Report for the Conowingo Relicensing Application Project, Harford and 

Cecil Counties, Maryland and Lancaster and York Counties, Pennsylvania (Sara et al 

2011b). During the Phase IA research, Exelon identified 19 AOIs with high localized 

erosion as well as a high probability for archaeological resources; nine of these were 

recommended for further field investigations. Subsequent Phase IB research entailed the 

excavation of a total of 369 shovel test pits dispersed throughout these nine AOIs. The 

results were presented in Conowingo Project Relicensing Application, Harford and Cecil 

Counties, Maryland and Lancaster and York Counties, Pennsylvania, Phase IB 

Archaeological Survey of Nine High Priority Areas of Interest (AOIs 6, 18, 19, 33, 36A, 

36B, 38, 39, and 45), FERC No. 405 (Sara et al., 2012b). During this study, seven new 

sites (18HA317, 18HA318, 18HA319, 18HA320, 18CE373, 18CE374, and 18CE375) 

and two isolated finds were documented bringing the total site count to 44 sites. As a 

result of both the Phase IA and IB studies, Exelon identified one site (18CE82) that has 

been previously determined to be eligible for listing on the National Register and one site 

(18CE16) that has been previously determined to be ineligible. Three previously 

recorded sites also considered to be eligible for listing (36LA51, 36LA56, 36LA67) and 

two sites (18CE14, 36LA69) were recommended as potentially eligible. Of these sites,

36LA67 is also located within the APE established for the Muddy Run Project. All seven 

of the newly identified sites were also recommended as potentially eligible. The 

remaining 30 sites in the Conowingo Project APE have not been evaluated, and their 

National Register eligibility is unknown.

Table 3-36 shows all archaeological and historic sites identified within the APEs 

for the Susquehanna River Projects.

Table 3-36. Recorded archaeological and historic sites identified within the 

Susquehanna River Projects APEs (Sources: Stallings and Franz, 2012; 

Exelon, 2012).

Resource 

Number Resource Type National Register Eligibility

York Haven Project

36DA3

(general) General prehistoric, open habitation n/a

36DA51 General prehistoric, open habitation Unknown

36DA52

(general) General prehistoric, open habitation n/a

36DA86

(general) General prehistoric, open habitation n/a
287

Resource 

Number Resource Type National Register Eligibility

36DA93 Late Woodland, open habitation Unknown

36DA94 Transitional, open habitation Unknown

36DA95 Late Archaic - Late Woodland, open 

habitation Unknown

36DA98 General prehistoric, open habitation Unknown

36DA99 Late Archaic, open habitation Potentially eligible

36DA100 Early Archaic, open habitation Potentially eligible

36DA101 Late Archaic; Late Woodland; 19th century, 

multi-component Potentially eligible

36DA102 Late Archaic open habitation Unknown

36DA103 Middle - Late Archaic open habitation Unknown

36DA104 Late Archaic, open habitation Unknown

36DA105 Late Archaic, open habitation Unknown

36DA106 Late Archaic, open habitation Unknown

36DA107 Late Archaic - Transitional Archaic, open 

habitation Unknown

36DA139 Island Late Archaic; Middle-Late Archaic, 

open habitation Unknown

36DA149 Late Archaic, open, unknown function Unknown

36DA150 General prehistoric; Late Woodland, open, 

unknown function Unknown

36DA151 Late Woodland, open, known function Unknown

36DA152 Archaic-Late Woodland, open, unknown 

function Unknown

36DA235 18th to 20th century, farmstead Potentially eligible

36YO256 Archaic-Late Woodland, open habitation Unknown

36YO264 General prehistoric, open habitation Unknown
288

Resource 

Number Resource Type National Register Eligibility

36YO300 Paleoindian-Archaic, Late Woodland, general 

historic, open, unknown function Unknown

36YO334 Unknown Unknown

Muddy Run Project

36LA67 Prehistoric open habitation Considered eligible

36LA103 Rockshelter Unknown

36LA368 Prehistoric open habitation Unknown

Conowingo Project

Maryland

18CE14 Multi-component Prehistoric Potentially Eligible

18CE16 Late Archaic Ineligible

18CE82 Rock art Eligible

18CE347 19th century domestic Unknown

18CE348 19th-20th century farm Unknown

18CE349 Industrial Susquehanna Canal Unknown

18CE366 Industrial Susquehanna Canal Lock Unknown

18CE373 Prehistoric, Archaic-Woodland village site; 

18th-20th century cemetery Potentially Eligible

18CE374 Prehistoric, open habitation Potentially Eligible

18CE375 Prehistoric, open habitation Potentially Eligible

18HA21 Transitional Archaic; 19th century canal Unknown

18HA240 19th-20th century canal lock gates Unknown

18HA248 Middle to Late Archaic short-term camp Unknown

18HA254 Middle to Late Archaic short-term camp Unknown

18HA255 Late Archaic short term camp Unknown

18HA256 Late Archaic Lithic Scatter; 18th century 

domestic site Unknown

18HA267 Late 19th-early 20th century barge/wreck Unknown

18HA268 19th-20th century barge/shipwreck Unknown
289

Resource 

Number Resource Type National Register Eligibility

18HA269 Historic landing or wharf site Unknown

18HA285 Mill Ruins Unknown

18HA317 19th-20th century domestic structure and 

refuse Potentially Eligible

18HA318 Archaic-Woodland base camp, 18th-20th 

century Potentially Eligible

18HA319 Prehistoric, unknown lithic scatter Potentially Eligible

18HA320 Woodland base camp, 18th-20th century Potentially Eligible

Pennsylvania

36LA28 Open habitation, prehistoric Unknown

36LA29 Open habitation, prehistoric Unknown

35LA34 Prehistoric open habitation Unknown

36LA35 Prehistoric open habitation Unknown

36LA43 Open habitation Unknown

36LA45 Open habitation Unknown

36LA47 Historic, prehistoric Unknown

36LA51 Open habitation Considered Eligible

36LA56 Prehistoric, open habitation Considered Eligible

36LA65 Late Archaic, open habitation Unknown

36LA67 Prehistoric, open habitation Considered Eligible

36LA68 Prehistoric, open habitation Unknown

36LA69 Prehistoric, open habitation Potentially Eligible

36LA70 Prehistoric, open habitation Unknown

36LA118 Prehistoric, open habitation Unknown

36LA120 Prehistoric, open habitation Unknown

36LA1252 Rockshelter Unknown

36LA1253 Prehistoric, open Unknown

36LA1254 Shelter Unknown

36YO381 Historic mill race Unknown
290

Historic Structures

York Haven Project

York Haven Power conducted an architectural survey and identified five historic 

structural resources in the project APE (Stallings and Franz, 2011). Three of these 

structural resources are located on Shelley Island: the Shelly Island Schoolhouse and two 

historic cemeteries. By letter dated May 2, 2011, the Pennsylvania SHPO determined 

that the Shelley Island Schoolhouse is ineligible for listing82 on the National Register 

(letter from D.C. McLearen, Chief, Division of Archaeology and Protection, 

Pennsylvania Historical and Museum Commission, Bureau for Historic Preservation, 

Harrisburg, Pennsylvania, to F. P. Stallings, Brockington Cultural Resources Consulting, 

Norcross, GA, May 2, 2011). The survey report also notes that cemeteries are generally

not eligible for listing on the National Register but can be eligible under the National 

Register criteria if they obtain their primary significance from graves of person of 

transcendent importance, from age, from distinctive design features, or from an 

association with historic events (National Park Service, 1992). York Haven Power 

recommended that the two cemeteries do not meet these criteria. The Three Mile Island 

nuclear plant is also located within the APE and has been previously determined eligible

for listing on the National Register. However, while this facility is technically located 

within the project APE, it is situated within an area excluded from FERC jurisdiction. 

Only the York Haven Project was identified within the APE as potentially eligible for 

listing on the National Register under Criterion A for its contribution to the history of 

hydroelectric power in the region between 1901 and 1904. It was also recommended as 

eligible under Criterion C because of its association with the John Augustus Dempwolf 

firm and reflects both utilitarian and Richardsonian Romanesque architectural styles. In 

its May 2, 2011, letter, the Pennsylvania SHPO concurred with these recommendations.

Muddy Run Project

Exelon conducted a study of potentially eligible historic structures associated with 

both the Muddy Run and Conowingo projects. The results of the study for the Muddy 

Run Project are presented in Final Report, Historic Structures Assessment Report for the 

Muddy Run Pumped Storage Project Relicensing Application, Drumore and Martic 

Townships, Lancaster County and Lower Chanceford and Peach Bottom Townships, 

York County, Pennsylvania (Henry and Jenkins, 2012a). A single structure, the historic 

Ritchie-Robinson House (ca. 1846), was identified. According to the report, the 

Pennsylvania SHPO had previously determined that the structure was ineligible for 

 

82 The Pennsylvania SHPO did not indicate why the schoolhouse is ineligible for 

listing; however, the final license application at page 273 states: “many of the buildings 

on Shelley Island are replacements of earlier structures that were destroyed or heavily 

damaged during the Hurricane Agnes Flood of 1972.” 
291

listing on the National Register in 2001. Exelon re-evaluated the structure at the request 

of the Pennsylvania SHPO (letter from D. C. McLearen, Chief, Division of Archaeology 

and Protection, Pennsylvania Historical and Museum Commission, Bureau for Historic 

Preservation, Harrisburg, Pennsylvania, to F. P. Stallings, Brockington Cultural 

Resources Consulting, Norcross, GA, January 6, 2011). Exelon recommended that the 

house remain ineligible because (a) its previous occupants, William Ritchie and Michael 

Robinson, were not persons of historical significance on the local, state, or national level; 

(b) the structure has been altered with modern materials and additions that have 

compromised the house’s integrity of design, materials, and workmanship; and (c) the 

farmstead itself does not contain a range of typical buildings and landscape features that 

would demonstrate important changes over time in the region’s agricultural history. In its 

December 28, 2012, response to the Commission’s November 2, 2012, Additional 

Information Request, Exelon explained that while the Pennsylvania SHPO’s concurrence

on this recommendation had been requested, no response had been received. The Muddy 

Run Project does not yet meet the 50-year threshold for National Register eligibility. 

However, Exelon’s historic structures report states that the system is potentially eligible 

for listing under National Register Criterion A (energy production), Criterion C

(engineering), and Criterion Consideration G, which recognizes significant architectural 

resources less than 50 years old. The report recommended further research and field 

survey to complete the Historic Structures Resource form for the Muddy Run facility and 

to formally evaluate its eligibility for the National Register.

Conowingo Project

A reconnaissance level architectural survey for the Conowingo Project identified a 

number of historic structures located within the project APE (table 3-37). The results of 

the study are presented in Final Report, Historic Structures Report for the Conowingo 

Hydroelectric Project Relicensing Application, Hanford and Cecil Counties, Maryland, 

FERC Project No. 405 (Henry and Jenkins, 2012b). Archival research identified four 

structures or structural districts currently listed on the National Register (HA-112, HA113, 

HA-1551, and HA1591). By letter dated May 1, 2012, the Pennsylvania SHPO stated that 

the Susquehanna and Tidewater Canal (HA-112) and the Columbia & Port Deposit 

Railroad (CE-1554) had been evaluated for another project and were determined ineligible

for inclusion in the National Register (letter from D.C. McClearen, Chief, Division of 

Archaeology and Protection, Pennsylvania Historical and Museum Commission, Bureau 

for Historic Preservation, Harrisburg, Pennsylvania, to C.E. Hicks, Exelon Corporation, 

Kennett Square, Pennsylvania, filed August 31, 2012). However, subsequently, the 

Pennsylvania SHPO reversed this determination and stated that these two structures are 

indeed eligible (letter from D.C. McClearen, Chief, Division of Archaeology and 

Protection, Pennsylvania Historical and Museum Commission, Bureau for Historic 

Preservation, Harrisburg, Pennsylvania, to K. Smith, Gomez and Sullivan Engineers, 

Henniker, NH, July 23, 2012). No reason for this change was provided. The Lower Deer 

Creek Valley Historic District (HA-1551) contains a number of contributing elements,

nine of which are within the project APE. While the boundaries of the Havre De Grace 
292

Historic District (HA-1591) are also located within the APE, no structures associated with 

the district are present in the APE. There are five additional previously documented 

resources in the APE, three of which (CE-874, HA-1877, and HA-1971) have also been 

previously determined to be eligible for listing on the National Register. Two others (HA1035 and HA-1183) are recommended as ineligible. One historic bridge (HA-1581) was 

demolished in 1997. A total of seven additional resources were newly identified during 

the study. All seven were recommended as ineligible for listing on the National Register. 

Table 3-37. Historic structures identified within the Susquehanna River Projects APEs

(Sources: Stallings and Franz, 2011; Henry and Jenkins, 2012a, 2012b).

Resource 

Number Resource Type National Register Eligibility

York Haven Project

Unassigned Shelley Island Schoolhouse Ineligible

Unassigned Shelley Family Cemetery Recommended ineligible

Unassigned Shelley Island Cemetery Recommended ineligible

Unassigned Three Mile Island Nuclear Plant Eligible

Unassigned York Haven Hydroelectric Project Eligible

Muddy Run Project

Unassigned Ritchie-Robinson House Recommended ineligible

Unassigned Muddy Run Hydroelectric Project Potentially eligible

Conowingo Project

CE-0874 Bell Manor Road Bridge Determined eligible 2001 

(per Exelon)

CE-1554/ 

1558 (new)

Columbia & Port Deposit Railroad 

including Bridge and Tunnels

Eligible (Pennsylvania

SHPO 7/23/2012)

CE-1555 

(new)

Perpendicular Lock of Susquehanna Canal Recommended ineligible

CE-1556 

(new)

Palmer House 900 Susquehanna Road Recommended ineligible

CE-1557 

(new)

McClenahan Bros./John W. Malone Quarry 

Building

Recommended ineligible
293

Resource 

Number Resource Type National Register Eligibility

HA-0112 Susquehanna and Tidewater Canal 

Southern Terminus

National Register listed 

1987, determined 

eligible (Pennsylvania

SHPO 7/23/2012)

HA-0113 Susquehanna and Tidewater Canal 

Lockmasters House

National Register listed 

1987

HA-1035 Old U.S. Route 1 (Glen Cove Road) Recommended ineligible

HA-1183 Whitney Cottage Recommended ineligible

HA-1581 MD 623 Bridge over Broad Creek Demolished in 1997

HA-1591 Havre De Grace Historic District National Register listed 

1982

HA-1877 County Road 19 Bridge Determined eligible 2001 

(per Exelon)

HA-1971 U.S. Route 1 bridge over Conowingo Dam 

(Conowingo Hydroelectric Facility)

Determined eligible 2001 

(per Exelon)

HA2210/2211 

(new)

Susquehanna Power Company Railroad 

Spur and Bridge

Recommended ineligible

HA-2212 

(new)

Trenton Flint and Spar Company Building

Ruins

Recommended ineligible

HA-2213 

(new) 

Bridge Recommended ineligible

HA-2214 

(new)

Culvert Recommended ineligible

HA-1551 Lower Deer Creek Valley Historic District Listed 1987

HA-191 Rock Run Mill Contributes to District

HA-195 Rock Run Bridge Toll House Contributes to District

HA-196 Rock Run Bridge Piers Contributes to District
294

Resource 

Number Resource Type National Register Eligibility

HA-376 Lapidum Warehouse Wharf Road Contributes to District

HA-377 Lapidum Inn site Contributes to District

HA-380 Abrahams/Nicholson House Contributes to District

HA-381 Pugh House/Ferncliff Contributes to District

HA-382 Lapidum Lock Contributes to District

HA-2190 Neff House Contributes to District

Traditional Cultural Properties

On June 12, 2009, the Commission initiated consultation with the Delaware 

Nation and inquired regarding its interest in the Susquehanna River Projects relicensing 

(letter from A. Miles, Director of Hydropower Licensing, FERC, Washington, D.C., to 

K. Holton, President, Delaware Nation, Anadarko, OK, dated June 12, 2009). The 

Commission offered to meet with the tribe to discuss any issues or concerns that the tribe 

might have. York Haven Power also consulted with the Delaware Nation during study 

plan development and on October 26, 2010, the tribe responded by email stating that it 

desired to be a consulting party.83 On April 7, 2011, York Haven Power provided the 

tribe with a copy of the cultural resources report for review and comment.84 The tribe 

was also provided a copy of the draft and final license applications. The Delaware 

Nation is also included on Exelon’s list of consulting parties. To date, no specific 

comments have been received from the Delaware Nation and no concerns regarding 

cultural resources in the project APE have been reported. On December 13, 2013, the 

 

83 October 26, 2010 email from J. Ross, Cultural Preservation Department, 

Delaware Nation, Anadarko, OK, to P. Stallings, Brockington and Associates, Inc. 

Norcross, Georgia. Filed December 28, 2012.

84 April 7, 2011 letter from F.P. Stallings, Brockington and Associates, Inc. 

Norcross, Georgia, to T. Francis, Cultural Preservation Director, Delaware Nation, 

Anadarko, OK. Filed June 12, 2009.
295

Onondaga Nation expressed an interest in the lower Susquehanna River Projects.

85 The 

tribe expressed concerns regarding cultural resources including traditional trails and trade 

routes in the vicinity of the Conowingo and Muddy Run project areas.

3.3.6.2 Environmental Effects

Project-Related Effects on Cultural Resources

Project-related effects on cultural resources within the APEs could occur from 

project operations, any proposed modifications to project facilities, changes in project 

boundaries, public use of project lands, and other activities. Project effects are 

considered to be adverse when an activity may alter, directly or indirectly, the 

characteristics of a historic property that qualify the property for inclusion in the National 

Register. If adverse effects are found, such effects would need to be resolved in 

consultation with the Maryland SHPO, Pennsylvania SHPO, and other parties. For the 

most part, assessment of effects to archaeological resources located within the APEs of 

the three projects focused on erosional effects.

York Haven Project 

In its application, York Haven Power stated that, because 17 of the 24 previously 

recorded sites are located on private lands, they were not assessed for project effects, and 

are not subject to the management responsibilities of York Haven Power. Six of the

17 sites (36DA100, 36DA101, 36DA235, 36DA51, 36DA98, 36DA99) are situated 

within a “FERC-designated exclusion zone” established for the Three Mile Island Project 

and are exempt from cultural resource consideration associated with the project. Several 

sites are located on York Haven Power fee lands that are either permitted lots (36DA139, 

36DA150, 36DA151) or are subject to non-intrusive agricultural practices (36DA104, 

36DA105). Two additional sites on fee lands are reported to have been heavily collected 

in the past (36DA102, 36DA103). Regardless, York Haven Power stated that its 

archaeological reconnaissance did not identify any project-related effects on any of the 24 

registered sites within the APE. Although areas of erosion were observed at several sites, 

and one site (36DA152) was identified as intermittently inundated, York Haven Power 

stated that any shoreline erosion at these sites is a consequence of natural river flows and 

not project operation (York Haven Power, 2012a). 

Five historic structural resources were identified within the York Haven Project 

APE. One of these has been determined to be ineligible for listing on the National 

Register, and three are recommended as ineligible. Effects to these resources have 

therefore not been assessed. The remaining two structures are eligible or potentially 

 

85 December 12, 3013 Motion to Intervene of the Onondaga Nation from Chief 

I. Powless, Jr., Secretary, Onondaga Nation, Nedrow, New York, filed 

December 24, 2013.
296

eligible for inclusion in the National Register. Of these, the Three Mile Island nuclear 

plant is located within the FERC-designated “exclusion zone.” No project effects on the 

plant were identified. However, normal operation and maintenance activities associated 

with the historic York Haven Hydroelectric Project facilities could adversely affect the 

character-defining features of this facility.

Muddy Run Project 

In its November 2, 2012, Additional Information Request, the Commission 

requested that Exelon provide a discussion of the current status of the three previously 

recorded sites identified during Phase IA cultural resources studies. In its 

December 28, 2012, response, Exelon explained that one site is currently inundated by 

the Muddy Run reservoir (36LA103), and one site is unaffected by project-related 

erosional impacts (36LA368). Exelon stated that AOI 1 and AOI 9, which were 

investigated during Phase IB studies, were located within the boundaries of the third site 

(36LA67) and that no cultural materials or features were observed. However, because 

this site lies within the APEs for both the Muddy Run and Conowingo projects, the 

Phase IB report recommends further investigation of the site as part of the Conowingo 

Project relicensing to determine the site’s condition and to assess erosional impacts (Sara 

et al., 2012a). Exelon concluded in section 3.3.8.2 of its application that the continued 

operation of the Muddy Run Project and “associated Project recreation” could affect 

cultural resources. Exelon also notes that siltation may be considered to have a positive 

effect in some situations because it provides a layer of protection.

Exelon’s application identifies a single architectural resource present within the 

Muddy Run Project APE. The Ritchie-Robinson House has been recommended as 

ineligible for listing on the National Register and therefore, project effects on this 

resource need not be assessed. Exelon’s historic structures report (Henry and Jenkins,

2012a) also identified the Muddy Run Hydroelectric Project system as a potential historic 

property. Because the system has not yet reached the 50-year threshold for National 

Register eligibility, Exelon did not complete an assessment of effects for this resource. 

Conowingo Project

Exelon concluded in section 3.3.8.2 of its application that the continued operation 

of the Conowingo Project and “associated Project recreation” could affect cultural 

resources. Exelon also noted that siltation may be considered to have a positive effect in 

some situations because it provides a layer of protection. Exelon’s Phase IB report (Sara 

et al., 2012b) also recommended additional field study of the eight sites investigated in 

the study to determine site boundaries and eligibility. However, by letter dated July 3, 

2012 (letter from D.L. Henry, Preservation Officer, Maryland Historical Trust, 

Crownsville, Maryland, to K.D. Bose, Secretary, FERC, Washington, D.C., July 3, 2012),

the Maryland SHPO provided comments on Exelon’s cultural resources investigations 

and stated that no further archaeological investigations were necessary for the relicensing 

at this time. Additionally, by email dated April 26, 2012, the Maryland SHPO stated that 

the removal of specified lands from the Conowingo Project boundary and from federal 
297

jurisdiction would not result in an adverse effect on the Susquehanna and Tidewater 

Canal terminus because the Maryland Historical Trust holds a perpetual preservation 

easement on the property (email from D.L. Henry, Preservation Officer, Maryland 

Historical Trust, Crownsville, Maryland, to D.S. Searman, Maryland DNR, Annapolis, 

Maryland, filed June 21, 2011). The Maryland SHPO concluded that continued operation 

of the Conowingo Project would have no adverse effect on historic properties, including 

the historic Conowingo Project Hydroelectric Project facilities. 

A ninth site investigated during the Phase IB study is located in Pennsylvania 

(36LA69). By letter dated February 16, 2012, the Pennsylvania SHPO recommended 

completing Phase II evaluations at this site because the site is threatened by 

ongoing erosion. 

Historic Properties Management Plans

York Haven Project 

In April 2012, York Haven Power prepared a draft HPMP to address projectrelated effects on historic properties and unevaluated cultural resources. The 

Pennsylvania SHPO provided comments on the draft HPMP (letter from D.C. 

McClearen, Chief, Division of Archaeology and Protection, Pennsylvania Historical and 

Museum Commission, Bureau for Historic Preservation, Harrisburg, Pennsylvania, to 

D. Weaver, York Haven Power Company, York Haven, Pennsylvania, 

September 14, 2012), and York Haven Power addressed those comments in a revised 

HPMP filed with the Commission on December 28, 2012 (Stallings and Franz, 2012). 

In its HPMP, York Haven Power proposes to appoint a cultural resources

coordinator and implement review procedures that would apply to non-routine 

maintenance activities, structural modifications, or additions that may be necessary in the 

future. Additionally, the HPMP includes measures and procedures for: (a) an employee 

cultural resources awareness program; (b) the treatment of inadvertent discoveries of 

cultural materials; (c) the treatment of human remains that may be identified during 

project activities; (d) additional archaeological investigations including protocols for any 

new construction activities intended to avoid affecting National Register-eligible 

resources; (e) any sale or transfer of project lands; (f) ground maintenance and 

landscaping within the project APE; (g) monitoring archaeological sites identified within 

the project APE including inspection and reporting policies; (h) potential effects on 

historic hydroelectric system structures; (i) activities that are exempt for further 

section 106 consultation; and (j) review and updates of the HPMP should license 

modifications become necessary or should regulation change. If these situations do not 

occur, the HPMP would be reviewed and revised every 10 years in consultation with the 

Commission, the Pennsylvania SHPO, interested Native American tribes, and other 

parties as appropriate.
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Muddy Run Project

Exelon stated that continued operation of the Muddy Run Project would not affect 

historic properties that are listed or eligible for listing on the National Register. For this 

reason, Exelon did not develop an HPMP for the Muddy Run Project. However, Exelon 

also stated that continued operation and maintenance and project-related recreation 

activities have the potential to affect sites and that “in some cases, sites are being affected 

by siltation, which may be considered a positive effect because it provides site 

protection.” Exelon proposes to perform section 106 consultation prior to any projectrelated ground-disturbing activity, including recreational development. If previously 

unidentified cultural resources are identified during such activity, Exelon would consult 

with the Pennsylvania SHPO and if necessary, prepare a cultural resources management 

plan to address the discovery in compliance with section 106.

In its January 31, 2014, comments, recommendations, preliminary terms and 

conditions, and preliminary prescriptions, Interior provides a 10(a) recommendation in 

accordance with the FPA that Exelon prepare an HPMP for the Muddy Run Project in 

consultation with the Pennsylvania SHPO and other parties.

Conowingo Project

In its HPMP, Exelon proposes to appoint a cultural resources coordinator and 

implement review procedures that would apply to non-routine maintenance activities, 

structural modifications, or additions that may be necessary in the future. Additionally, 

the HPMP includes measures and procedures for: (a) appointment of a cultural resources 

coordinator who would be responsible for overseeing implementation of the HPMP and 

coordinating consultation activities; (b) potential project effects on the historic 

Conowingo Project facility and other historic structures, including consultation with the 

Maryland SHPO or Pennsylvania SHPO and others as appropriate; (c) ground-disturbing 

activities that have the potential to affect archaeological resources; (d) monitoring all 

archaeological sites and 19 AOIs identified within the project APE including inspection 

and reporting policies and a requirement to consult with the Maryland SHPO or 

Pennsylvania SHPO and others as appropriate should effects be identified; (e) Phase II 

evaluations at site 18LA69 as requested by the Pennsylvania SHPO within 1 year of 

HPMP implementation; (f) archaeological public outreach and interpretation programs, 

(g) the treatment of inadvertent discoveries of cultural materials; (h) emergency situations 

with the potential to affect historic properties; (i) consultation with the Delaware Nation

and the Onondaga Nation; (j) the treatment of human remains that may be identified 

during project activities; (k) the curation of any cultural materials that may be recovered 

during archaeological fieldwork; (l) annual reporting to the Pennsylvania SHPO and 

Maryland SHPO; and (m) review and amendment of the HPMP as needed.
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Our Analysis

York Haven Project

York Haven Power’s HPMP includes many of the standard requirements of a 

HPMP. However, some measures contained within the draft HPMP would benefit from 

clarification and/or more detail, and there are other measures that would be worth

inclusion in the final HPMP. 

A comprehensive archaeological survey of all lands within the York Haven 

Project APE was not undertaken, and most of the previously documented sites identified 

in the APE are situated on privately held lands. Where possible, these sites were 

inspected by boat. In its HPMP, York Haven Power states that it has no management 

responsibilities for these sites without right-of-way entry permission from the relevant

landowners. However, section 106 requires the assessment of effects regardless of 

property ownership. Section 3.6 of the HPMP specifies that consultation with the 

Pennsylvania SHPO, Tribal Historic Preservation Officers, Indian Tribes, and other 

parties would be conducted if shoreline monitoring efforts identify project-related effects 

on archaeological sites in the future. However, it is not clear that this requirement in the 

HPMP also applies to sites on private lands within the project boundary. If project 

effects to sites on private lands are identified during monitoring, inclusion in the HPMP 

of a requirement to seek access to assess those sites would ensure compliance with 

section 106. If such consultation is necessary for sites on private lands, the HPMP should 

reflect that it would include specific requests for landowner access permission to evaluate 

any affected sites located on private property.

In its HPMP, seven sites were identified that are located on York Haven Power fee 

lands (36DA102, 36DA103, 36DA104, 36DA105, 36DA139, 36DA150, 36DA151). 

York Haven Power states that some of these sites are subject to no-till farming, and 

others are reported to have been heavily collected in the past. York Haven Power 

proposes to undertake annual monitoring of these sites. However, full recordation and 

National Register evaluation of these sites would not require private landowner 

permission and would enable an assessment of any potential effects in a timelier manner. 

Inclusion in the HPMP of a plan and schedule to evaluate sites on fee lands for their 

National Register eligibility would ensure that any effects on sites owned by York Haven 

Power are fully considered in accordance with section 106.

Appendix B of the HPMP provides a schedule for monitoring of archaeological 

sites located within the project APE based on potential effects, property ownership, and 

whether or not the sites are already being monitored under the requirements of an HPMP 

developed for the Three Mile Island Project. The monitoring plan and schedule is 

appropriate, but excludes monitoring of two sites: 36YO300 and 36YO334. These two 

sites are not listed in Appendix B. While they are situated on privately held lands, it is 

not clear if they are located on the shoreline and can be monitored by boat like other sites 

on private lands, or if they are interior sites that cannot be monitored. Inclusion of these 
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two sites in the monitoring schedule, or clarification regarding why they were excluded, 

would ensure that they are appropriately addressed.

Muddy Run Project

Exelon proposes to prepare a cultural resources management plan only if cultural 

materials are identified during project-related activities. However, there are several 

reasons why the development of an HPMP prior to that time would be beneficial. 

In the Commission’s November 2, 2012, Additional Information Request, we 

requested that Exelon provide a discussion of the current status of the three sites 

identified during Phase IA cultural resources studies, including archaeological site 

36LA67. In its response, Exelon stated that the two AOIs (1 and 9) investigated during 

Phase IB studies were located within the boundaries of this site and that no cultural 

materials or features were observed. However, according to figure 4-1 of the Phase IA 

report (Sara et al., 2011a), AOI 1 is located on the northern shoreline of Muddy Run 

reservoir and AOI 9 is located in the vicinity of the dam.86 According to figure 3-12 of 

the report, site 36LA67 is not located in either of these two locations but is in proximity 

to the project transmission line. Potential effects associated with the maintenance of this 

line are not addressed in the application. Further, this site is situated within an area that 

may be affected by reservoir discharge. The current condition of the site therefore 

remains unclear, and its National Register eligibility status, and that of the other two sites 

identified in the APE (36LA103, 36LA368), is unknown. Two additional sites are 

located outside of the project boundary (36LA70, 36LA47) but also appear to be close to 

the reservoir discharge area and near the transmission line. Potential project effects on 

these sites as a result of discharge and transmission line access and maintenance should 

be considered in an HPMP. 

While Exelon has stated that there are no project effects on historic properties, the 

three sites identified in the Phase IA report have not been formally evaluated and 

therefore remain potentially eligible for listing on the National Register. As noted by 

Exelon in its application, and as discussed above, these sites and others could be affected 

by continued operation, maintenance, and recreational activity associated with the 

project. Additionally, in its application, Exelon states that “some sites” are being affected 

by siltation and notes that this may result in a positive effect. However, the specific sites 

affected by siltation are not identified, and siltation does not necessarily result in a 

positive effect in all situations. Only a formal assessment of effects on a case-by-case 

 

86 The Phase IA report prepared for the Muddy Run Project (Sara et al., 2012a) 

does not identify any AOI where site 36LA67 is located. However, this area is also 

located within the APE for the Conowingo Project and is identified as AOI 13 in the 

Phase IA report prepared for that project (Sara et al., 2011b). AOI 13 is described as 

having a high potential for archaeological resources.
301

basis in consultation with the Pennsylvania SHPO would establish whether there is any 

effect. To our knowledge, the Pennsylvania SHPO has only concurred that no further 

work is needed within the two AOIs investigated during the Phase IB study and has not 

concurred with Exelon’s recommendation that the project will not affect historic 

properties. 

A comprehensive archaeological survey of all lands within the Muddy Run Project 

APE was not undertaken, and only 2 of the 12 AOIs identified during Phase IA studies 

were inspected during Phase IB studies. The potential for additional, previously 

unidentified cultural resources that may be eligible for listing on the National Register 

within the project APE remains. Exelon’s Phase IB report recommends that additional 

AOIs should be surveyed during the development of a future HPMP (Sara et al., 2012a). 

Additionally, while the pumped storage project facility may not currently meet the 

general 50-year threshold for National Register eligibility, the facility will meet that 

threshold within 2 years. Staff agrees with Exelon’s historic structures report (Henry and 

Jenkins, 2012a) that recommends evaluating the system for listing. 

Staff agrees with Interior’s recommendation that development of an HPMP would 

be appropriate for this undertaking because unevaluated properties that are potentially 

eligible for listing on the National Register and may be affected by future operation, 

maintenance, and project-related recreational activities, are located within the Muddy 

Run Project APE. Preparation of an HPMP that (1) includes a plan for additional 

archaeological investigations of additional AOIs and other areas, (2) addresses the 

National Register eligibility of the three identified archaeological sites and the Muddy 

Run Project system, and (3) requires evaluation of potential project-related effects on 

these and other resources that may be affected by maintenance, operation, and 

recreational activities (including sites potentially affected by transmission-related 

activities such as sites 36LA70, 36LA47), would ensure that cultural resources are 

appropriately addressed in compliance with section 106. Further, the HPMP should be 

prepared in accordance with the Advisory Council and Commission’s joint guidance 

document for preparing hydroelectric project HPMPs (FERC and Advisory 

Council, 2002).

The Delaware Nation and the Onondaga Nation have been identified as the 

federally recognized tribes with cultural ties to the Muddy Run Project area. In 

accordance with section 106, the tribes should be included in all correspondence related 

to cultural resources; however, the application does not describe consultation with the 

tribes completed by Exelon to date. The HPMP should specify when consultation with 

the Delaware Nation and the Onondaga Nation would be required, and copies of all 

consultation documentation should be included as an appendix to the HPMP.

Conowingo Project

Exelon’s August 2012 HPMP includes many of the requirements of a HPMP. 

However, there is background information provided that is not entirely clear, and there 
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are several measures that would benefit from clarification and/or more detail. We also 

suggest other measures worthy of inclusion in the HPMP. 

Exelon proposes a new project boundary that excludes lands downstream from 

Conowingo dam. The project APE includes most of these lands because Exelon states 

they may be affected by project operation in the future. The inclusion of these lands in 

the project APE is appropriate. However, while the Maryland SHPO concluded in its 

July 3, 2012, letter that continued operation of the Conowingo Project would have no 

adverse effect on historic properties, it is our understanding that this determination is 

primarily considering erosion and other physical effects on cultural resources. Interior’s 

January 31, 2014, comments, however, express concern for the potential loss of resource 

protection, including protections to cultural resources, should lands be removed from the 

project boundary. Further, in accordance with 36 CFR 800.5(a)(2)(vii) of the regulations 

implementing section 106 of the NHPA, the “transfer, lease, or sale of property out of 

Federal ownership or control without adequate and legally enforceable restrictions or 

conditions to ensure long-term preservation” of historic properties may constitute an 

adverse effect. 

For this reason, all lands within the current project boundary could be affected by 

a change in the project boundary and must be included in the project APE. This would 

include a narrow strip of land located in the current project boundary that extends

downstream from Spencer Island along the west side of the river to the city of Havre de 

Grace, Maryland. Exelon excluded this area from the APE because it did not identify any 

physical project effects here. The APE maps provided in the HPMP therefore do not 

include this area. According to the Phase IA report (Sara et al., 2011a), this strip of land 

contains four additional previously recorded archaeological sites (18HA240, 18HA267, 

18HA268, 18HA269). None of these sites are discussed in the text of the HPMP, 

although site 18HA269 is listed in the HPMP’s table 3-2. Inclusion of these lands in the 

project APE would ensure that all four of these sites, and any other previously 

unidentified resources that may be present in this area, remain protected under 

the HPMP. 

While the Commission determined that the removal of the Susquehanna and 

Tidewater Canal Southern Terminus (HA-112) from the project boundary would have an 

adverse effect on this resource (letter from C. Yeakel, Division of Hydropower 

Compliance, FERC, Washington, D.C., to R. Little, Maryland SHPO, Maryland Historic 

Trust, Crownsville, Maryland, May 14, 2010), as mentioned above, on April 26, 2011, 

the Maryland SHPO subsequently determined that removal of lands from the project 

boundary would not adversely affect this structure. However, inclusion in the HPMP of 

requirements to inventory any lands within the project APE (particularly AOIs identified 

in the Phase IA study that were not subject to Phase IB study), evaluate any identified 

cultural resources for National Register eligibility, and address potential effects prior to 

any sale or transfer of those lands would ensure that cultural resources located on these 

lands would be appropriately considered in compliance with section 106. This 

requirement would primarily relate to lands owned in fee by Exelon, although sites on 
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privately held lands might also be affected. If project effects of any kind on cultural 

resources on private lands are identified over a new license term, Exelon would make a 

good faith effort to obtain access to the property to conduct appropriate studies. 

In sections 3.3.8.1.3 and 3.3.8.2 of its application, Exelon states that nine 

archaeological sites were identified in the project APE during Phase IB studies. 

However, while Exelon is correct there were nine sites documented during this study, 

(two previously recorded sites and seven newly identified sites), the total number of sites 

identified in the Conowingo Project APE is 48, including 37 sites that had been identified 

during the Phase IA study and the additional four sites downstream of Spencer Island 

discussed above. Further, Exelon’s HPMP includes a plan to monitor only 37 of the 48 

archaeological sites located within the project APE. Revision of the HPMP to include all 

identified 48 sites would ensure that they are appropriately addressed in accordance with 

section 106. 

A total of 27 historic structures or historic districts were identified within the 

Conowingo Project APE (see table 3-37). However, table 3-1 of Exelon’s Conowingo 

HPMP lists only seven historic structures. One of the seven structures in the table is the 

Lower Deer Creek Valley Historic District (HA-1551); three structures (HA-191, HA195, HA-196) are identified in the table as being contributing elements of the district that 

are located within the project APE. However, according to Exelon’s historic structures 

report (Henry and Jenkins, 2012b), six additional structures that contribute to the district 

(HA-376, HA-377, HA-380, HA-381, HA-382, HA-2190) are also located within the 

project boundary and APE and have been excluded from the HPMP. Additionally, there 

are 14 other structures that have been excluded. Three of these structures are listed on 

the National Register, one is eligible for listing, and one has been demolished. The 

remaining nine structures have been recommended as ineligible for listing but to our 

knowledge, neither the Maryland SHPO nor the Pennsylvania SHPO has concurred with 

these recommendations. Inclusion of all 27 structures in the HPMP or an explanation 

regarding why they need not be considered in the HPMP would clarify their current status 

and ensure that they are considered under the requirements of section 106.

Of the seven structures listed in table 3-1, the National Register eligibility of the 

Columbia & Port Deposit Railroad is identified as both “undetermined” and “not 

eligible.” In its letter dated July 23, 2012, the Pennsylvania SHPO determined that this 

structure is indeed eligible for listing on the National Register. 

Exelon’s historic structures report (Henry and Jenkins, 2012b), identifies site 

HA-1971 as both “Conowingo Hydroelectric Facility” and “U.S. 1 over Susquehanna 

River (Conowingo Dam),” while the description provided in table 3-1 of the HPMP 

identifies it as the “Conowingo Hydroelectric Facility.” The structures report explains 

that, in 2001, a Historic Bridge Inventory Form was prepared for the U.S. Route 1 bridge 

(which consists of the dam), and that the bridge was recommended as eligible for listing 

on the National Register under Criterion C. According to the structures report, the 

Maryland Historical Trust accepted the Historic Bridge Inventory on April 3, 2001, and 
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at that time, recommended that a separate form be completed for Conowingo dam and the 

hydroelectric components of the structure. However, Exelon’s structures report further 

explains that Exelon’s consultant was informed by the Maryland SHPO on 

October 21, 2010, that a separate form and evaluation of the hydroelectric component of 

the facility need not be completed for the hydroelectric facility. Clear identification in 

the HPMP of the name of the structure provided on the form for HA-1971 and 

documentation of the Maryland SHPO’s current position on the necessity of any new 

form for the Conowingo Project structures would settle the issue. Exelon’s HPMP 

contains a list of the character-defining features of the facility, which includes the 

powerhouse and machinery, the bridge, and the dam. In the HPMP, Exelon stated that it 

would consult with the Maryland SHPO to establish a PA that would detail project 

activities involving the system that can be completed without Maryland SHPO review. A 

list of activities exempt from SHPO review is provided in the HPMP. While we are not 

aware of any concurrence yet received from the SHPO on this list, staff finds that the 

activities listed would not require specific section 106 consultation. As the Commission 

intends to execute a PA with the Maryland SHPO that would implement a final HPMP 

that includes a list of exempt activities, an additional PA between Exelon and the 

Maryland SHPO would not be necessary. However, should the Maryland SHPO identify 

additional activities not currently included on the list, the HPMP could be revised to 

include those activities. 

Exelon’s HPMP states that, should ground-disturbing activities be proposed within 

the APE in an area that contains an existing archaeological site or could contain an 

archaeological site, Exelon would consult with the appropriate SHPOs regarding 

potential effects of the activity. However, in areas that have not been subject to 

archaeological survey, the HPMP does not specify how Exelon would make the 

determination that archaeological sites would or would not be affected. Inclusion in the 

HPMP of how these determinations would be made would provide clarity.

In the HPMP, Exelon proposes to conduct a public outreach program to inform the 

public about culturally significant areas within the APE to discourage vandalism and 

looting. While such outreach programs are worthwhile, they should focus on the general 

sensitivity of the project as a whole and not identify the locations of specific culturally 

sensitive areas.

The Delaware Nation and the Onondaga Nation have been identified as the 

federally recognized tribes with cultural ties to the Conowingo Project area. In its 

HPMP, Exelon states that any correspondence would be directed to the tribe, but the 

HPMP does not specify when consultation with the Delaware Nation or the Onondaga 

Nation would be required nor does the application or HPMP describe consultation with 

the tribes completed by Exelon to date. In accordance with section 106, the tribes should 

be included in all correspondence related to cultural resources and copies of consultation 

documentation should be included as an appendix.
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Programmatic Agreements

The Commission intends to execute PAs among the Commission, Maryland

SHPO, Pennsylvania SHPO, and the Advisory Council (should it choose to participate). 

York Haven Power, Exelon, participating tribes, and others, as appropriate, would be 

invited to sign the PAs as concurring parties. Any licenses issued for the projects would 

include a stipulation that would implement the PA for that project. If the HPMPs are

finalized prior to license issuance, the PAs would include a measure to implement the 

final HPMP upon license acceptance. If the HPMPs are not finalized prior to license 

issuance, the PAs would instead require each HPMP to be finalized within a specified 

period of time post license acceptance, typically 1 year. Revising and implementing the 

HPMPs for the York Haven and Conowingo Projects to include Commission staff’s 

additional measures and corrections, and the development of an HPMP for the Muddy 

Run Project, in consultation with the Maryland SHPO, Pennsylvania SHPO, participating 

tribes, and the Commission, would ensure that potential adverse effects of continued

operation, maintenance, recreation or other activities on cultural resources would be 

addressed over the term of the licenses.

3.3.7 Aesthetic Resources

3.3.7.1 Affected Environment

The Susquehanna River from Harrisburg to its confluence with the upper 

Chesapeake Bay passes through diverse natural and human built environments. The river 

corridor provides a wide range of geologic features, habitats, and human development 

such as hydropower plants and industrial yards dating back to the early 1900s. The river 

has a variety of unique geologic features including river potholes, exposed bedrock, steep 

cliffs, and wide deep pools. River banks and shorelines are generally covered in 

deciduous forest with residential lots, recreation access, and transportation infrastructure 

visible throughout. The river provides water to four hydroelectric facilities, one pumped 

storage project, two nuclear power plants, and one steam-electric station. Lands 

surrounding the river are rural with majority in agricultural uses. Higher elevations 

provide opportunities for sweeping views across the rolling topography and river valley 

and are dominated by the rural setting through which the river transverses.

At the York Haven Project, aesthetic features of Lake Frederic include views of 

surrounding shorelines, islands, and project features. Human development includes 

shoreline development (residential lots, recreation access, and commercial marinas), open 

space, and larger industrial features such as Three Mile Island nuclear generating station 

and Brunner Island Station, a coal-fired steam electric generating plant located about 1.5 

miles downstream of York Haven. 

Project features are only visible in proximity to the main dam, powerhouse, and 

east channel dam and fishway. The red brick powerhouse is characteristic of industrial 

structures built in the early 1900s while most of the other structures are of grey concrete. 

The islands within the impoundment consist of mixed uses including industrial (Three 
306

Mile Island generating station), cultivated crops, recreational lots, and developed 

recreation sites. The remainder of the York Haven Project area visual landscape includes 

rural community residential and commercial development, regional infrastructure (e.g., 

railroad), and deciduous forests. 

Aesthetic features surrounding the Muddy Run Project are dominated by rolling 

hills covered with deciduous forest, agricultural uses, and recreation uses associated with 

Muddy Run Park and WMA and adjacent to the powerhouse. Views within the 

Recreation Lake and Muddy Run Park areas consist of manicured park settings with 

maintained lawns, mature trees, and public recreation infrastructure like buildings, picnic 

shelters, sports areas, a boat ramp, campgrounds, and other amenities described in detail 

in section 3.3.5, Recreation and Land Use Resources. The visual setting within the 

WMA is natural with the majority of the area in forested setting with small tracts of land 

cleared for parking areas or feed plots. Large portions of the project around the upper 

reservoir near the intake towers are not visible to the public because of limited access. 

The powerhouse is visible from Conowingo Pond and is set against the steep topography 

between the Muddy Run powerhouse along the Conowingo Pond shoreline and the upper 

reservoir. The powerhouse exhibits large industrial-type features dominated by grey 

concrete, the riprapped shoreline, overhead crane, transformer, substation, transmission 

lines, and parking areas. Portions of the upper reservoir dam are also visible from 

Conowingo Pond. 

U.S. Route 1 crosses the top of Conowingo dam providing views of the reservoir 

and river downstream to passing motorists. Project structures of this area include the 

powerhouse, Conowingo dam, and the spillway. These facilities dominate the views 

from Fisherman’s Park/Shures Landing immediately below the powerhouse. Within 

Conowingo Pond, views include islands, residential lots, recreational access, and 

industrial features such as the Muddy Run Project facilities and PBAPS located on the 

west shoreline near the midpoint of the reservoir. Lands adjacent to the project boundary 

offer diverse aesthetic qualities because of the rolling topography, vegetation, agricultural 

uses, and general open space. 

3.3.7.2 Environmental Effects

For all three projects, existing project facilities and operations are generally 

consistent with the existing visual aesthetics of the area. Some facilities are visible on the

landscape and contrast with the surrounding setting, but have not been shown to detract

substantially from the natural character of the area. York Haven Power and Exelon do 

not propose any specific measures for aesthetic resources. However, proposed 

environmental measures, such as construction of the nature-like fishway, operation of the 

Muddy Run Project, and debris removal from Conowingo Pond, may affect visual 

aesthetics over the term of any new licenses for the projects.
307

Effects of Construction of the Nature-Like Fishway

York Haven Power proposes to construct a nature-like fishway near the eastern 

end of the main dam and Three Mile Island. The fishway would consist of a series of 

rock weirs allowing fish passage over the main dam. Construction would include: 

improving existing access roads on Three Mile Island; a temporary, two-lane access road 

for retrieval and transport of river rock across the river bed below the dam; three staging 

areas on Three Mile Island; a cofferdam; a rock ramp fishway; an attraction water 

system; and concrete abutment walls. The new feature would extend from the toe of the 

dam into the existing reservoir, which at the apex of the main dam and Three Mile Island 

is about 10 feet high. The proposed fishway would be about 300 feet wide and about 

500 feet long. York Haven Power expects the rock retrieval period of the project to last 

3 years and final construction to be finished 8 years after any license is issued. 

Our Analysis

Nature-like fishways are designed to simulate the geomorphology, hydraulics, and 

functions of natural river channels. Construction of the nature-like fishway would 

require the installation of a temporary cofferdam to isolate the construction of the rock 

ramp and other structures (e.g., intake gates and attraction water system). Large 

excavators would shuttle between extracting exposed river rock and transporting the 

rocks to the fishway weirs for about 3 years. The use of native river rocks would give the 

new structure a more naturally appearing aesthetic than traditional geometric fish ladders. 

The east edge of the fishway would terminate in a combination of a poured concrete 

abutment and conveyance system designed to control flows in the rock weirs and provide 

attraction flows to the base of the fishway, respectively. The finished fishway would be 

most visible to kayakers and other recreation users in the main channel downstream from 

the dam, in proximity to Three Mile Island. Between April and June when water is 

directed into the fishway for operations, the fishway would be covered in water as it 

flows through the artificial pool-riffle weirs. During times of the year when flows are not 

sufficient to spill and fill the fishway naturally, the rock ramp weirs would be dry with 

some pools of water.

Effects of Operation of the Muddy Run Pumped Storage Project

During project scoping, commenters raised concerns about the effects of lighting 

and project-associated noise on visitors to the area. Specifically, commenters raised 

concerns about the lighting and noise associated with the operations (generation and 

pumping) at Muddy Run; however, no specific locations or receptors were identified. 

Lights are installed on the intake towers in the upper reservoir and throughout the 

powerhouse area and access road along the shore with Conowingo reservoir.

Exelon does not propose, nor does any other entity recommend specific measures 

that pertain to managing light and noise specifically related to the project. 

Our Analysis 
308

Several formal recreation facilities are located within or in proximity to the Muddy 

Run Project boundary, including Wissler’s Run Park, Muddy Creek Boat Launch, the 

Lock 15 Interpretive Area, Susquehannock State Park, Cold Cabin Boat Launch, Muddy 

Run WMA, and Muddy Run Recreation Park (see section 3.3.5, Recreation and Land 

Use Resources). Additionally, several islands are located in the Susquehanna River near 

the Muddy Run Project. Although there are no formal recreation facilities on these 

islands, they provide opportunity for passive daytime recreation, and some contain lots 

that are currently leased by cottage owners. Nighttime use of the islands is restricted to 

cottage owners.

Exelon recorded noise levels and took representative photos of day- and nighttime conditions from 10 representative locations in relative proximity to project features. 

Figure 3-21 shows the locations of these public areas. 
309

Figure 3-21. Aesthetic (audio and visual) assessment locations (Source: Exelon, 2012, 

as modified by Staff).
310

Typical operation of the Muddy Run Project consists of pumping water from 

Conowingo Pond to the Muddy Run reservoir during low-load (typically nighttime) 

periods when energy costs are low, then generating (releasing water from the Muddy Run 

reservoir back to Conowingo Pond) during high load (typically daytime) periods. 

Exelon’s aesthetic study results indicate that the level of impact (intensity of light 

or noise) is related to proximity to the powerhouse and that some sites are impacted more 

than others. The Muddy Run powerhouse is clearly visible during both day and night 

from islands directly across from the powerhouse (Turkey Island, Lower Bear Island, and 

Big Chestnut Island), as well as from Wissler’s Run Park. At the Muddy Creek Boat 

Launch, Lock 15 Interpretive Area, and Susquehannock State Park (public recreation 

areas in relative proximity to the powerhouse), the powerhouse usually cannot be clearly 

seen during the day, but the glow of its lights is visible at night. Other facilities, such as 

the transmission line towers on Lower Bear Island (day) and the intake towers lights 

(night), are generally visible at these sites. 

At Cold Cabin Boat Launch, no facilities can be seen during the day, and only the 

intake tower lights can be seen at night. At Muddy Run WMA, only the dam and 

reservoir can be seen during the day, and a faint glow from the powerhouse and/or intake 

towers can sometimes be seen at night. Lastly, at Muddy Run Recreation Park, only the 

power reservoir can be seen during the day; no lights can be seen at night.

Project lighting at nighttime is highest at select locations (i.e., Conowingo 

Islands); however, the Conowingo Islands have restrictions against public use at night. 

The amount of lighting visible from the surrounding locations changes with the seasons 

as leaf off conditions allow better sight lines to see the project’s night lighting. 

Noise has the potential to disturb visitors to the Muddy Run Project and vicinity, 

as well as to some of the Conowingo Project formal recreation sites. Noise-producing 

equipment at the project includes pump-generators, ventilation fans, transformers, fans on 

the transformers, and powerlines. Exelon measured the ambient acoustic environment 

(the all-encompassing sound in a given environment) at the 10 locations. The soundscape 

at each location is influenced by motorboat, vehicular, and air traffic; construction 

activities; human activities; and other natural sound sources. To capture the ambient 

sound levels, Exelon recorded 5 seconds of ambient noises occurring every 5 minutes and 

averaged these for the duration (deleting loud, temporary sounds like a passing truck or 

overhead airplane) of the recording. 

Exelon’s results show that average ambient noises ranged from 34 to 

61 decibels (dB) across all sites and seasons.87 Not every site was dominated by sounds 

emanating from the powerhouse; at some sites the project was audible and at other, more 

 

87 Logarithmic scale known as the decibel scale (dB) used to quantify sound 

pressure into a manageable range.
311

distant locations, the project was not audible at all. Table 3-38 summarizes the average 

noise levels at each site by season for both day and night. Comparison of these 

measurements with table 3-39 suggests that at locations dominated by the sounds of the 

powerhouse, noise levels are comparable to quiet urban settings. 

Table 3-38. Audio assessment results (Source: Exelon, 2012, modified by Staff).

Site Name

Spring Summer Fall Winter

Day Night Day Night Day Night Day Night

Turkey Island 48 52 50 56 54 57 52 57

Lower Bear Island 44 44 43 53 50 52 46 52

Big Chestnut 

Island 40 39 43 50 42 46 42 52

Wissler’s Run Park 40 41 44 48 41 45 48 50

Muddy Creek Boat 

Launch 39 39 41 55 49 54 41 47

Lock 15 

Interpretive Area 41 38 49 61 47 55 42 44

Susquehannock 

State Park 46 37 46 57 44 58 40 49

Cold Cabin Boat 

Launch 38 37 46 53 46 51 42 54

Muddy Run WMA 37 34 45 59 46 54 42 43

Muddy Run Park 41 36 45 52 42 50 43 43

Key: Red=powerhouse noise dominant; Yellow=powerhouse noise audible but not 

dominant; Green=powerhouse noise not audible.

Exelon’s aesthetic assessments indicate that the current levels of light are relative 

to the proximity of the viewer to the light source and clearly visible from the islands and 

Wissler’s Run park; however, nighttime use of the islands is prohibited. Public 

recreation sites on the west side of the river across from Muddy Run do not have clear 

sight lines but can see the glow of the lights on the powerhouse at night. The same 

assessment for noise indicates that noise at sites where powerhouse sounds are audible, 

but not the dominant sound, measure as much noise as the sites close to the powerhouse. 

This indicates that there are sufficient background noises other than the powerhouse that 

contribute to the overall noise levels in the project vicinity. 
312

Table 3-39. Loudness comparison chart (Source: Exelon, 2012).

Common Outdoor Sounds

Noise Level 

(dBA)

Threshold of human hearing 0

Quiet rural nighttime 20

Quiet suburban nighttime 30

Quiet urban nighttime 40

Quiet urban daytime 50

Heavy traffic at 300 feet 60

Lawn mower at 100 feet 70

Boat (single outboard) at 50 feet 80

Threshold of hearing damage due to 

prolonged exposure

85

Jet fly-over at 1,000 feet 110

Effects of Debris Removal from the Conowingo Project

As discussed in section 3.3.5, Recreation and Land Use Resources, some of the 

natural and human-generated debris moving through the Susquehanna River watershed 

gets trapped behind the hydroelectric facilities on the mainstem of the lower Susquehanna 

River. Most debris is transported during high-flow events, particularly during March and 

April. Exelon has participated in clean-up efforts and debris studies dating back to 1982, 

and these studies reported that 75 percent of the total estimated volume of debris was 

discharged during high-flow events (January through May). A 1989 cooperative 

agreement by the operators of York Haven, Safe Harbor, Holtwood, Conowingo, SRBC, 

and regulatory agencies led to routine debris removal actions during normal to low flows. 

As such, Exelon routinely employs cranes and skimmers to reduce the amount of debris 

buildup behind Conowingo dam during low-flow periods. 

Visitor perceptions and attitudes towards the debris were not recorded during 

relicensing studies. Within Conowingo Pond, debris typically accumulates near the dam 

intakes, within tributaries, and under or behind the railroad trestle bridges. Debris 

trapped in the reservoir makes its way to the dam where it is corralled and removed. The 

majority of the debris is natural; however, artificial debris is intermixed with the large 

woody and natural debris degrading the visual appearance of the accumulated materials. 

The large accumulation of debris near the powerhouse intakes is visible for short 

durations from traffic on U.S. Route 1 (most notably for vehicles moving east to west) 

and boaters near the dam. Most of the other areas of debris accumulation are only visible 

from the water. 
313

Our Analysis

Exelon’s proposal to continue to remove debris from in front of the intakes is 

consistent with the cooperative agreement with the upstream hydroelectric projects and 

agencies. The amount of debris arriving at Conowingo Pond on an annual basis is a 

function of the flood flows during the winter months. The Susquehanna watershed is 

flood-prone, so passing and removing debris is a dynamic process causing Exelon to react 

to what arrives. Visually, the amount of debris on the pond, in tributaries, and collected 

in front of the intakes varies from year to year. Although debris removal coincides with 

the warmer, recreation season when more visitors are able to see Exelon actively 

removing the debris, those activities are concentrated in the area near the dam. 

3.3.8 Socioeconomics

3.3.8.1 Affected Environment

For this socioeconomics discussion, the local area is defined as the area 

encompassing and immediately surrounding the project areas along the Susquehanna 

River. This includes residential and commercial developments, in addition to 

recreational and park lands, along the river shorelines. Socioeconomic information is 

also provided for the study area, which is the five-county region surrounding the projects. 

The York Haven Project is located in York, Lancaster, and Dauphin counties, 

Pennsylvania, with a total of eight townships and/or boroughs within the project area. 

The Muddy Run Project is located in Lancaster County, and Peach Bottom Township is 

the only census-designated place (CDP) within this project boundary. The Conowingo 

Project area includes Lancaster and York counties in Pennsylvania and Harford and Cecil 

counties in Maryland. 

Population

The state of Maryland experienced a 9 percent population increase between 2000 

and 2010, ranking 23rd in the United States for growth rate, and Pennsylvania 

experienced a 3 percent population increase between 2000 and 2010, ranking 42nd in the 

United States for rate of population growth (Census Scope, 2010a). Tables 3-40 and 3-41

summarize population trends for both states and all five counties.
314

Table 3-40. Population in Cecil and Harford Counties, Maryland, and the state of 

Maryland (Source: Census Scope, 2010a & b).

Year Maryland Cecil Harford

2010 5,773,552 101,108 244,826

2000 5,296,486 85,951 218,590

1990 4,781,468 71,347 182,132

1980 4,216,975 60,430 145,930

1970 3,922,399 53,291 115,378

1960 3,100,689 48,408 76,722

Table 3-41. Population in Dauphin, Lancaster, and York counties, Pennsylvania, and 

the state of Pennsylvania (Source: Census Scope, 2010a & b).

Year Pennsylvania Dauphin Lancaster York

2010 12,702,379 268,100 519,445 434,972

2000 12,281,054 251,798 470,658 381,751

1990 11,881,643 237,813 422,822 339,574

1980 11,863,895 232,317 362,346 312,963

1970 11,793,909 223,834 319,693 272,603

1960 11,319,366 220,255 278,359 238,336

Within York County, the York Haven Project is partially located within York 

Haven Borough (population 709), Goldsboro Borough (population 952), and Newberry 

Township (population 15,285). Within Dauphin County, the project is partially located 

in Londonderry Township (population 5,232), Lower Swatara Township (population 

8,268), Middletown (population 8,901), and Royalton Borough (population 907). The 

project is also partially located within Conoy Township (population 3,194) in Lancaster 

County (U.S. Census Bureau, 2010a). 

The Muddy Run Project is located entirely within Lancaster County and partially 

within Peach Bottom Township (population 4,813) (United States Census Bureau,

2010a). The project is not located within any other CDPs or communities in Lancaster 

County. 
315

The Conowingo Project boundary contains no CDPs or communities, but includes 

two incorporated municipalities in Harford County: Aberdeen and Havre de Grace. The 

City of Havre de Grace has a population of 12,952, and the City of Aberdeen has a 

population of 14,959. The project boundary includes lands within Cecil County, but no 

CDPs or communities.

Employment and Income

Employment

Employment in Dauphin, Lancaster, and York counties represented 2, 4, and 

4 percent of total employment in the state of Pennsylvania in 2012, respectively; Cecil 

and Harford counties represented 2 and 4 percent of total employment in the state of 

Maryland in 2012, respectively (BLS, 2013). Unemployment rates in Dauphin, 

Lancaster, and York counties were lower than in the state of Pennsylvania as a whole; 

while unemployment rates were higher in Cecil and Harford counties than in the state of 

Maryland as a whole in 2012. Of the five counties in the study area, Lancaster County 

had the lowest unemployment rate in 2012, while Cecil County had the highest 

unemployment rate (BLS, 2013). Employment levels along with unemployment rates are 

presented in table 3-42.

Table 3-42. Employment and unemployment percent numbers 2012 (Source: 

BLS, 2013).

Geography Total 

Employment

Unemployment 

Rate (%)

United States 142,469,000 8.1

Maryland 2,909,571 6.8

Cecil 46,810 8.4

Harford 129,802 7.0

Pennsylvania 5,973,407 7.9

Dauphin 128,581 7.7

Lancaster 250,980 6.6

York 211,027 7.7

Dauphin County is less rural than the other counties in the study area with the city 

of Harrisburg, the capital of Pennsylvania, located on the east side of the Susquehanna 

River within the county. According to the 2012 Census, the primary industries in 

Dauphin County are education (23 percent of total employment); retail trade (11 percent 

of total employment); and professional, scientific, management, administrative and waste 
316

management services and public administration (10 percent of total employment)

(U.S. Census Bureau, 2012). 

Lancaster, York, Cecil, and Harford counties are largely rural in nature and 

dominated by agricultural land uses. However, employment in agriculture represents 

between less than 1 and 3 percent of total employment in these counties. The two 

industrial sectors with the largest employment in these counties are educational services 

and healthcare, and manufacturing sectors. The educational services and healthcare 

sector accounted for 23 percent of total employment in both Lancaster and York counties 

and 22 percent in both Harford and Cecil counties in 2012 (U.S. Census Bureau, 2010b) 

(EDC, 2012). Employment in manufacturing accounted for 16 and 18 percent of total 

employment in Lancaster and York counties, respectively, and 11 and 7 percent of total 

employment in Cecil and Harford counties, respectively, in 2012. Employment in retail 

trade accounted for between 10 and 14 percent of total employment in these counties in 

2012 (U.S. Census Bureau, 2010b).

Income

Per capita income in the Pennsylvania counties is lower than per capita income in 

the Maryland counties within the study area. Lancaster County is lower than the 

Pennsylvania average, while York and Dauphin County have similar per capita incomes 

to that of Pennsylvania. Dauphin and Lancaster counties have experienced negative 

growth in per capita income between 2000 and 2010; York County has experienced no 

growth; and the state of Pennsylvania has only experienced a slight increase in per capita 

income during this period. Cecil and Harford counties have slightly lower per capita 

income than that of Maryland, although all per capita income in the geographies has 

grown in Maryland (U.S. Census Bureau, 2010b). Table 3-43 shows per capita income 

for the study area and the states of Maryland and Pennsylvania. 

Table 3-43. Per capita income for Pennsylvania and Maryland counties in 2000 and 

2010, with percent change (inflation adjusted, 2010$) (Source: U.S.

Census Bureau, 2010b).

Geography 2000 2010 Percent Change

Maryland $32,435 $34,469 6%

Cecil County $27,079 $28,358 5%

Harford County $30,685 $33,372 9%

Pennsylvania $26,440 $27,004 2%

Dauphin County $28,028 $27,052 -3%

Lancaster County $25,830 $24,871 -4%

York County $26,678 $26,702 0%
317

Project Power

All three projects offer benefits to the region in terms of providing low-cost 

energy; local, county, and state tax payments; employment and economic activity related 

to operation and maintenance of the project facilities; and public use facilities owned and 

operated by others that are located within the project areas. The York Haven Project has 

an installed capacity of 19.62 MW while the Muddy Run and Conowingo projects have 

installed capacities of 800.25 and 574.54 MW, respectively. This amount of capacity at 

York Haven is capable of providing the equivalent of approximately 14,700 households 

with electricity each year; while the capacity at Muddy Run and Conowingo can provide

the equivalent of approximately 600,000 and 430,000 households with electricity each 

year, respectively, assuming 1 MW of power services an average of 750 households per 

year (York Haven Power, 2012a; Exelon, 2012b).

Project Taxes

York Haven Power and Exelon are subject to a variety of state income and local 

property taxes. In 2010, these taxes totaled $143,615 for York Haven Power. In 2011, 

Exelon paid $5 million and $10.5 million in state income and local property taxes on the 

Muddy Run and Conowingo projects, respectively. Taxes paid by these two companies 

positively affect the public because state taxes are deposited into general funds, which are 

directed, in part, back to the county and city governments (York Haven Power, 2012; 

Exelon, 2012).

Project Employment

The York Haven Project is operated and maintained by 22 full-time employees,

and the Muddy Run and Conowingo projects are each operated by 56 employees. These 

employees positively affect the local and regional economy by consuming goods and 

services and paying taxes (York Haven Power, 2012; Exelon, 2012).

Project Recreation

As described in section 3.3.5, Recreation and Land Use Resources, recreation 

resources in the region provide a full range of activities, including boating, canoeing, 

swimming, fishing, water sports, hiking, camping, hunting, biking, and nature viewing. 

Recreation visitors spend money on activities and at business establishments during their 

stay in the region, supporting local and regional economies. This visitor spending 

supports local jobs and income, which, in turn, induces additional economic activity 

within the local economy, providing additional employment, income, and tax revenues to 

local governments. 

Additionally, York Haven Power leases 288 recreational lots to the public for a 

small fee, while Exelon leases 420 lots for seasonal residential cottage use (as described 

in section 3.3.5, Recreation and Land Use Resources). Residents of these lots provide a 

positive benefit to the local economy through local spending that supports local jobs and 
318

income, which, in turn, induces additional economic activity within the local economy,

providing additional employment, income, and tax revenues to local governments. These 

leaseholders also provide a small income to York Haven Power and Exelon through their 

fee payments. 

3.3.8.2 Environmental Effects

York Haven Project

Current project operation has provided significant socioeconomic benefit to the 

area. The continued operation of the project, which includes the proposed construction of 

a new fish ladder, would have a positive effect on local and regional socioeconomic 

conditions by providing both direct and indirect jobs and significantly contributing to 

state, county, and local tax revenues. There are no plans for changing the operation of 

the facility that would significantly reduce these benefits, and there are no proposed 

environmental measures that would have a significant negative socioeconomic effect per 

the application provided by York Haven Power. 

Our Analysis

Continued operation of the project, as well as project spending related to 

construction of the new fish ladder and other ongoing maintenance, would have a positive 

effect on the regional economy. Positive effects would be realized through support of 

companies providing materials and services for the project, the presence of the project 

workforce and associated consumer spending, and project tax contributions to state and 

local governments. As discussed in section 3.3.5, Recreation and Land Use Resources, it

is York Haven Power’s current policy not to create any new cottage lease lots within the 

project boundary and that any leases for existing cottages that are abandoned or become 

damaged and are not replaced by structures conforming to all applicable regulations will 

be terminated. Termination of lot leases would likely cause a decrease in spending in the 

local economy, along with a decrease in local income and property taxes, and result in 

negative impacts to the local economy. However, these permit terminations are expected 

to occur over a number of decades, resulting in minimal long-term impacts to the local 

economy. The proposed, continued operation of the York Haven Project would have no 

unavoidable adverse effect on socioeconomic resources. 

Muddy Run and Conowingo Projects

Current operations have provided significant socioeconomic benefit to the area. 

The continued operation of these projects would have a positive effect on local and 

regional socioeconomic conditions by providing both direct and indirect jobs and 

significantly contributing to state, county, and local tax revenues. There are no plans for 

changing the operation of the facilities at these projects that would reduce these benefits. 

Therefore, there are no proposed environmental measures that would impact 

socioeconomics per the application provided by Exelon. 
319

Our Analysis 

Changes to Muddy Run and Conowingo project operations are not proposed, so no 

changes to socioeconomic conditions are expected. Project operations would continue to 

supply low cost electricity. Continued operation of the projects would have a positive 

effect on the regional economy through support of companies providing materials and 

services for the projects, the presence of the project workforces and associated consumer 

spending, and project tax contributions to state and local governments. Continued 

maintenance of the projects’ facilities, including recreation facilities, would result in 

some construction-related jobs, although the labor force required is likely to be small and 

temporary. Continued operation of the Muddy Run and Conowingo projects would have 

no known unavoidable adverse effects on socioeconomic resources.

Exelon’s current policy of not creating any new leases on cottages within the 

Conowingo Project boundary, as discussed in section 3.3.5, Recreation and Land Use 

Resources, would continue. In addition, as existing cottages are abandoned or become

damaged and are not replaced due to local zoning restrictions, leases would be 

terminated. Termination of lot leases would likely result in a decrease in spending in the 

local economy along with a decrease in local income and property taxes, resulting in

negative impacts to the local economy. However, removal of leased cottages from 

Conowingo’s land is expected to occur over many decades and would not result in 

significant adverse effects on socioeconomic resources. 

3.4 NO-ACTION ALTERNATIVE

Under the no-action alternative, the projects would continue to operate as they 

have in the past. None of York Haven Power’s or Exelon’s proposed measures or the 

resource agencies’ recommendations and mandatory conditions would be required. 
320

4.0 DEVELOPMENTAL ANALYSIS

In this section, we look at the York Haven, Muddy Run, and Conowingo projects’ 

use of the Susquehanna River for hydropower purposes to see what effect various 

environmental measures would have on the projects’ costs and power generation. Under 

the Commission’s approach to evaluating the economics of hydropower projects, as 

articulated in Mead Corp.,88 the Commission compares the current project cost to an 

estimate of the cost of obtaining the same amount of energy and capacity using a likely 

alternative source of power for the region (cost of alternative power). In keeping with 

Commission policy as described in Mead Corp., our economic analysis is based on 

current electric power cost conditions and does not consider future escalation of fuel 

prices in valuing the hydropower project’s power benefits.

For each of the licensing alternatives, our analysis includes an estimate of: (1) the 

cost of individual measures considered in the EIS for the protection, mitigation, and 

enhancement of environmental resources affected by the projects; (2) the cost of 

alternative power; (3) the total project cost (i.e., for construction, operation, maintenance, 

and environmental measures); and (4) the difference between the cost of alternative 

power and total project cost. If the difference between the cost of alternative power and 

total project cost is positive, the project produces power for less than the cost of 

alternative power. If the difference between the cost of alternative power and total 

project cost is negative, the project produces power for more than the cost of alternative 

power. This estimate helps to support an informed decision concerning what is in the 

public interest with respect to a proposed license. However, project economics is only 

one of many public interest factors the Commission considers in determining whether, 

and under what conditions, to issue a license.

4.1 POWER AND DEVELOPMENTAL BENEFITS OF THE PROJECTS

Table 4-1 summarizes the assumptions and economic information we use in our 

analysis for the York Haven Project, based on information provided by York Haven 

Power in its license application and subsequent submittals. Tables 4-2 and 4-3 

summarize the assumptions and economic information we use in our analysis for the 

Muddy Run and Conowingo projects, respectively, based on information provided by 

Exelon in its license application and subsequent submittals. We find that the values 

provided by the applicants are reasonable for the purposes of our analysis. For each 

project, cost items common to all alternatives include: taxes and insurance costs; 

 

88 See Mead Corporation, Publishing Paper Division, 72 FERC ¶ 61,027 

(July 13, 1995). In most cases, electricity from hydropower would displace some form of 

fossil-fueled generation, in which fuel cost is the largest component of the cost of 

electricity production.
321

estimated capital investment required to develop the project; licensing costs; normal 

operation and maintenance cost; and Commission fees.

Table 4-1. Parameters for economic analysis of the York Haven Project (Sources: 

York Haven Power and Staff).

Parameter Valuea

Period of analysis (years) 30

Term of financing (years) 20

Federal income tax rate, (%) 35.00

Local tax rate, (%) 3.00

Insurance rate Included in the operation and maintenance cost

Energy value, $/MWh 39.75

Capacity value, ($/kW-year) 45.53

Interest rateb 8.00

Discount ratec 8.00

Net investment $900,000 (2011)

Licensing costd, $ $3,000,000 (2011)

Operation and maintenance, $/year $4,822,547 (2011)

Commission fees, $/yeare $54,129

a Values provided by York Haven Power in the license application, unless otherwise 

noted.

b Interest rate assumed by Staff.

c Assumed by Staff to be same as interest rate.

d Excludes protection, mitigation, and enhancement measures. 

e Commission fees are the estimated value for 2013 from the FERC website.
322

Table 4-2. Parameters for economic analysis of the Muddy Run Project (Sources: 

Exelon and Staff).

Parameter Valuea

Period of analysis (years) 30

Term of financing (years) 20

Federal income tax rate, (%) 34.9

Local tax rate, (%) 3.00

Insurance rate Included in the operation and maintenance cost

Energy valueb, $/MWh 51.34

Pumping energyb, $/MWh 27.76

Capacity valueb ($/kW-year) 73.53

Ancillary services value,b $/year $8,602,000

Interest ratec 8.00

Discount rated 8.00

Net investment, $ $140,505,000 (2011)

Licensing cost, $e $7,026,000 (2011)

Operation and maintenance, $/year $6,857,000 (2011)

Commission fees, $/yearf $1,201,106 

a Values provided by Exelon in the license application unless otherwise noted.

b Values from Exelon, filed with the Commission on March 24, 2014.

c Interest rate assumed by Staff.

d Assumed by Staff to be same as interest rate.

e Excludes protection, mitigation, and enhancement measures. 

f Commission fees are the estimated value for 2013 from the FERC website.
323

Table 4-3. Parameters for economic analysis of the Conowingo Project (Sources: 

Exelon and Staff).

Parameter Valuea

Period of analysis (years) 30

Term of financing (years) 20

Federal income tax rate, (%) 34.9

Local tax rate, (%) 3.00

Insurance rate Included in the operation and maintenance cost

Energy valueb, $/MWh 40.55

Capacity valueb, ($/kW-year) 73.53

Ancillary services valueb, $/year $405,000

Interest ratec 8.00

Discount rated 8.00

Licensing cost, $e $14,989,000 (2011)

Operation and maintenance, $/year $15,985,000 (2011)

Annual capital cost, $/year $15,974,000 (2011)

Commission fees, $/yearf $1,209,228 

a Values provided by Exelon in its license application unless otherwise noted.

b Values from Exelon, filed with the Commission on March 24, 2014.

c Interest rate assumed by Staff.

d Assumed by Staff to be same as interest rate.

e Excludes protection, mitigation, and enhancement measures. 

f Commission fees are the estimated value for 2013 from the FERC website.

4.2 COMPARISON OF ALTERNATIVES

Tables 4-4, 4-5, and 4-6 summarize, for the York Haven, Muddy Run, and 

Conowingo projects, respectively, the installed capacity, annual generation, cost of 

alternative power, estimated total project cost, and difference between the cost of 

alternative power and total project cost for each of the alternatives considered in this EIS: 

no-action, the applicant’s proposal, and the staff alternative.
324

Table 4-4. Summary of the annual cost of alternative power and annual project cost for 

three alternatives for the York Haven Project (Source: Staff).

No Action

York Haven 

Power’s 

Proposal

Staff 

Alternative

Installed capacity (MW) 19.62 19.62 19.62

Annual generation (MWh) 132,271 131,771 131,771

Dependable Capacity (MW) 17.57 17.57 17.57

Annual cost of alternative power 

($/MWh)

$6,058,0104

5.80

$6,037,750

45.82

$6,037,750

45.82

Annual project cost ($/MWh) $5,777,920

43.68

$6,374,440

48.38

$6,370,400

48.34

Difference between the cost of 

alternative power and project cost 

($/MWh)

$280,090

2.12

($336,690)

(2.56)

($332,650)

(2.52)

Table 4-5. Summary of the annual cost of alternative power and annual project cost for 

three alternatives for the Muddy Run Project (Source: Staff).

No Action

Exelon’s 

Proposal

Staff 

Alternative

Installed capacity (MW) 800.25 800.25 800.25

Annual generation (MWh) 1,615,813 1,615,813 1,614,313

Annual pumping (MWh) 2,096,726 2,096,726 2,094,726

Dependable Capacity (MW) 1,070 1,070 1,070

Annual cost of alternative power 

($/MWh)

$169,563,420

104.94

$169,563,420

104.94

$169,470,580

104.98

Annual project cost ($/MWh) $118,797,090

73.52

$119,329,530

73.85

$118,972,540

73.70

Difference between the cost of 

alternative power and project cost 

($/MWh)

$50,766,330

31.42

$50,233,890

31.09

$50,498,040

31.28
325

Table 4-6. Summary of the annual cost of alternative power and annual project cost for 

three alternatives for the Conowingo Project (Source: Staff).

No Action

Exelon’s 

Proposal

Staff 

Alternative

Installed capacity (MW) 574.54 574.54 574.54

Annual generation (MWh) 1,823,193 1,823,193 1,823,293

Dependable Capacity (MW) 566.14 566.14 566.14

Annual cost of alternative power 

($/MWh)

$115,955,070

63.60

$15,955,070

63.60

$115,961,430

63.60

Annual project cost ($/MWh) $81,232,410

44.56

$83,685,030

45.90

$84,861,530

46.54

Difference between the cost of 

alternative power and project cost 

($/MWh)

$34,722,660

19.04

$32,270,040

17.70

$31,099,900

17.06

4.2.1 No-Action Alternative

Under the no-action alternative, the York Haven, Muddy Run, and Conowingo 

projects would continue as currently constructed and operated.

The York Haven Project would have a total capacity of 19.62 MW, a dependable 

capacity of 17.57 MW, and an average annual generation of 132,271 MWh. The average 

annual cost of alternative power would be $6,058,010, or $45.80/MWh. In total, the 

average annual project cost would be $5,777,920, or $43.68/MWh. Overall, the project 

would produce power at a cost which is $280,090, or $2.12/MWh, less than the cost of 

alternative power.

The Muddy Run Project would have a total capacity of 800.25 MW, a dependable 

capacity of 1,070 MW, an average annual generation of 1,615,813 MWh, and pumping 

energy requirements of 2,096,726 MWh. The average annual cost of alternative power 

would be $169,563,420, or $104.94/MWh. In total, the average annual project cost 

would be $118,797,090, or $73.52/MWh. Overall, the project would produce power at a 

cost which is $50,766,330, or $31.42/MWh, less than the cost of alternative power.

The Conowingo Project would have a total capacity of 574.54 MW, a dependable 

capacity of 566.14 MW, and an average annual generation of 1,823,193 MWh. The 

average annual cost of alternative power would be $115,955,070, or $63.60/MWh. In 

total, the average annual project cost would be $81,232,410, or $44.56/MWh. Overall, 

the project would produce power at a cost which is $34,722,660, or $19.05/MWh, less

than the cost of alternative power.
326

4.2.2 Applicants’ Proposals

Under the applicants’ proposal, the existing projects would be modified or 

enhanced as described by the applicants, and would include environmental measures to 

protect and enhance project resources. The individual costs of these changes are 

presented in tables 4-7, 4-8, and 4-9.

Under York Haven Power’s proposal, the York Haven Project would have a total 

capacity of 19.62 MW, a dependable capacity of 17.57 MW, and an average annual 

generation of 131,771 MWh. The average annual cost of alternative power would be 

$6,037,750, or $45.82/MWh. In total, the average annual project cost would be 

$6,374,440, or $48.38/MWh. Overall, the project would produce power at a cost which 

is $336,690, or $2.56/MWh, more than the cost of alternative power.

Under Exelon’s proposal, the Muddy Run Project would have a total capacity of 

800.25 MW, a dependable capacity of 1,070 MW, an average annual generation of 

1,615,813 MWh, and pumping energy requirements of 2,096,726 MWh. The average 

annual cost of alternative power would be $169,563,420, or $104.94/MWh. In total, the 

average annual project cost would be $119,329,530, or $73.85/MWh. Overall, the 

project would produce power at a cost which is $50,233,890, or $31.09/MWh, less than 

the cost of alternative power.

Under Exelon’s proposal, the Conowingo Project would have a total capacity of 

574.54 MW, a dependable capacity of 566.14 MW, and an average annual generation of 

1,823,193 MWh. The average annual cost of alternative power would be $115,955,070, 

or $63.60/MWh. In total, the average annual project cost would be $83,685,030, or 

$45.90/MWh. Overall, the project would produce power at a cost which is $32,270,040, 

or $17.70/MWh, less than the cost of alternative power.

4.2.3 Staff Alternative

The staff alternative would include the respective staff-recommended additions, 

deletions, and modifications to each applicant’s proposed environmental protection and 

enhancement measures. For the York Haven, Muddy Run, and Conowingo Projects, 

tables 4-7, 4-8, and 4-9, show the respective staff-recommended additions, deletions, and 

modifications to each applicant’s proposed environmental protection and enhancement 

measures, and the estimated cost of each.

For the York Haven Project, based on a total installed capacity of 19.62 MW, a 

dependable capacity of 17.57 MW, and an average annual generation of 131,771 MWh, 

the cost of alternative power would be the same as for the applicant’s proposal: 

$6,037,750, or $45.82/MWh. The average annual project cost would be $6,370,400, or 

$48.34/MWh. Overall, the project would produce power at a cost which is $332,650, or 

$2.52/MWh, more than the cost of alternative generation.
327

For the Muddy Run Project, based on a total installed capacity of 800.25 MW, a 

dependable capacity of 1,070 MW, an average annual generation of 1,614,313 MWh, and 

pumping energy requirements of 2,094,726 MWh, the cost of alternative power would be 

$169,470,580, or $104.98/MWh. The average annual project cost would be 

$118,972,540, or $73.70/MWh. Overall, the project would produce power at a cost 

which is $50,498,040, or $31.28/MWh, less than the cost of alternative generation.

For the Conowingo Project, based on a total installed capacity of 574.54 MW, a 

dependable capacity of 566.14 MW, and an average annual generation of 

1,823,293 MWh, the cost of alternative power would be $115,961,430, or $63.60/MWh. 

The average annual project cost would be $84,861,530, or $46.54/MWh. Overall, the 

project would produce power at a cost which is $31,099,900, or $17.06/MWh, less than 

the cost of alternative generation.

4.3 COST OF ENVIRONMENTAL MEASURES

Tables 4-7, 4-8, and 4-9 give the cost of each of the environmental enhancement 

measures considered in our analysis for the York Haven, Muddy Run, and Conowingo

projects, respectively. We convert all costs to equal annual (levelized) values over a 30-

year period of analysis to give a uniform basis for comparing the benefits of a measure to 

its cost.
328

Table 4-7. Cost of environmental mitigation and enhancement measures considered in assessing the environmental 

effects of continuing to operate the York Haven Project (Source: Staff and York Haven Power).

Enhancement/Mitigation Measure Entity

Capital 

Costa

(2014$)

Annual 

Costa

(2014$)

Levelized 

Annual Costb

(2014$)

Geology and Soils Resources

1. Develop an erosion and sediment control plan for

construction of the nature-like fishway. 

York Haven Power, 

Staff

$5,000 $0 $370c

Aquatic Resources

2. Continue to operate and maintain the existing east 

channel fishway for upstream fish passage.

York Haven Power, 

Settling Parties, Staff

$0 $0 $0d

3. Continue the current downstream juvenile American 

shad passage protocol, which calls for the operation of 

units 1-6 (Kaplan and propeller units) to be first online 

and last offline during the juvenile shad downstream 

migration period (which typically is from October 1 

through November 30). If river flows exceed the capacity 

of units 1-6, unit 14 would be operated, and if flows 

exceed the capacities of units 1-6 and 14, units 7-13, and 

15-20 would be operated in ascending order.

York Haven Power,

Settling Parties, Staff

$0 $0 $0d

4. Provide a year-round, continuous, minimum flow 

from the project of 1,000 cfs and an average daily 

minimum flow of 2,500 cfs, or inflow, whichever is less. 

York Haven Power, 

Settling Parties, Staff

$0 $0 $0d

5. Continue to operate the project in a run-of-river mode 

when inflow to the project is less than 3,000 cfs, without 

deliberate impoundment drawdown or storage for 

purposes of generating electricity in particular time 

periods.

York Haven Power, 

Settling Parties, Staff

$0 $0 $0d
329

Enhancement/Mitigation Measure Entity

Capital 

Costa

(2014$)

Annual 

Costa

(2014$)

Levelized 

Annual Costb

(2014$)

6. Pass about 370 cfs through the forebay sluice gate for 

1 or 2 hours in the morning during weekdays if river flows 

exceed the sum of the turbine hydraulic capacity, flows 

through the nature-like fishway, once constructed, flows 

through the east channel, and flows (if any) over the main 

dam from May 1 through June 30 to facilitate downstream 

passage of post-spawning adult American shad and during 

the fall American shad passage period to facilitate 

downstream passage of juvenile American shad.

York Haven Power, 

Settling Parties, Staff

$0 $0 $0e

7. Pass about 370 cfs through the forebay sluice gate 

between the hours of 5 and 11 p.m. during the entire 

juvenile American shad passage period to facilitate 

downstream passage of juvenile American shad.

York Haven Power, 

Settling Parties, Staff

$0 $0 $0e

8. Develop designs within 4 years of license issuance 

for (1) removal of obstructions in or deepening of the 

downstream plunge pool from the forebay sluice gate; and 

(2) a chute structure to convey flows beyond the roadway 

on the downstream side of the cable alley structure to 

protect outmigrating juvenile and adult American shad 

during passage to the downstream plunge pool.

York Haven Power, 

Settling Parties, Staff

$20,000 $0 $1,480f

9. Cooperate with resource agencies and other interested 

parties to conduct a lower Susquehanna River downstream 

eel migration study. This compensation would include 

monitoring of silver eels at the project and providing 

$25,000 to support the study.

York Haven Power, 

Settling Parties, Staff

$25,000 $0 $1,850g
330

Enhancement/Mitigation Measure Entity

Capital 

Costa

(2014$)

Annual 

Costa

(2014$)

Levelized 

Annual Costb

(2014$)

10. Conduct a site-specific silver eel route of passage 

study as described in appendix G of the Settlement 

Agreement including the potential for providing $50,000 

to resource agencies for collection and tagging of silver 

eels at upstream locations.

York Haven Power, 

Settling Parties, Staff

$50,000 $0 $3,700g

11. Conduct a site-specific eel survival study as 

described in appendix H of the Settlement Agreement.

York Haven Power, 

Settling Parties, Staff

$50,000 $0 $3,700f

12. Conduct a downstream eel passage improvement 

study if downstream eel passage goals are not achieved 

with provisions for subsequent monitoring and 

adjustments.

York Haven Power, 

Settling Parties, Staff

$0 $0 $0h

13. Until the nature-like fishway is completed, provide a 

minimum flow of 2,000 cfs at east channel dam and a 

spillage flow of 4,000 cfs at the main dam during the 

American shad upstream passage season when the east 

channel fishway is in operation (generally from mid-April 

through mid-June). 

York Haven Power, 

Settling Parties, Staff

$0 $0 $0e

14. Until the nature-like fishway is completed, after the 

American shad upstream passage season until the end of 

the resident fish passage season (the earlier of December 

15 or until the average daily river temperature is ≤ 40°F), 

maintain a minimum flow of 400 cfs in the east channel 

downstream of the east channel fishway during the period 

that the east channel fishway is operated to allow 

upstream passage of resident fish species, per the June 

2010 Consent Order and Agreement between York Haven 

Power and Pennsylvania DEP.

York Haven Power, 

Settling Parties, Staff

$0 $0 $0e
331

Enhancement/Mitigation Measure Entity

Capital 

Costa

(2014$)

Annual 

Costa

(2014$)

Levelized 

Annual Costb

(2014$)

15. Release an instantaneous minimum flow of 1,500 cfs 

to ensure adequate downstream flows to allow the full 

capacity operation of the Brunner Island Station.

PPL Brunner Island $0 $0 $0i

16. Construct, operate, and maintain a nature-like 

fishway with required attraction flows. 

York Haven Power, 

Settling Parties, 

Interior, Staff

$6,315,520 $145,890 $549,100j

17. Upon completion of the nature-like fishway, conduct 

American shad upstream passage effectiveness studies 

using telemetry beginning during the second year of 

nature-like fishway operation.

York Haven Power, 

Settling Parties,

$220,000 $0 $16,280f

18. Upon completion of the nature-like fishway, conduct 

a juvenile American shad headrace turbine avoidance 

study consistent with design criteria included in appendix 

D of the Settlement Agreement.

York Haven Power, 

Settling Parties, Staff

$50,000 $0 $3,700f

19. If the juvenile American shad headrace turbine 

avoidance goals are not achieved, implement measures 

that would enhance the effectiveness and conduct a 

supplemental juvenile American shad headrace turbine 

avoidance study within 2 years of implementing the 

measures.

York Haven Power,

Settling Parties, Staff

$0 $0 $0h

20. Upon completion of the nature-like fishway, provide 

an average daily minimum flow in the east channel below 

the east channel dam of 267 cfs year round.

York Haven Power, 

Settling Parties, Staff

$0 $0 $0e
332

Enhancement/Mitigation Measure Entity

Capital 

Costa

(2014$)

Annual 

Costa

(2014$)

Levelized 

Annual Costb

(2014$)

21. Upon completion of the nature-like fishway, provide 

a minimum of 5 percent of the river flow through the 

nature-like fishway during the American shad upstream 

passage season such that when inflows to the project are 

between 5,000 and 150,000 cfs, total flow through the 

nature-like fishway would range from about 1,000 to 

7,500 cfs, depending on inflow.

York Haven Power, 

Settling Parties, Staff

$0 $0 $0e

22. Upon completion of the nature-like fishway, provide 

a minimum flow of 200 cfs through the nature-like 

fishway when river elevation is at the crest of the main 

dam and outside of the American shad upstream passage 

season.

York Haven Power, 

Settling Parties, Staff

$0 $0 $0e

23. Upon completion of the nature-like fishway, to the 

extent controllable by York Haven Power, when flows 

exceed the hydraulic capacity of all available generating 

units, manage flows to maximize flow over the main dam 

and the nature-like fishway.

York Haven Power, 

Settling Parties, Staff

$0 $0 $0e

Terrestrial Resources

24. Conduct vegetation surveys, wetland delineations, 

invasive species surveys, rare species surveys, bog turtle 

habitat assessments, and bald eagle surveys in the area of 

the nature-like fishway prior to construction.

York Haven Power, 

Interior, Staff

$50,000 $0 $3,700f
333

Enhancement/Mitigation Measure Entity

Capital 

Costa

(2014$)

Annual 

Costa

(2014$)

Levelized 

Annual Costb

(2014$)

Recreation and Land Use

25. Develop and implement a recreation management 

plan, and update the plan every 12 years consistent with 

every other Form 80 reporting period deadline.

Staff $40,000 $1,160 $3,710l

26. Maintain existing recreation facilities on four islands 

in Lake Frederic and the recreation facilities at the 

powerhouse, including a portage trail for canoeists and 

fishing access along the downstream face of the 

powerhouse, and consult with the resource agencies about 

recreation management and strategies every 10 years after 

the effective date of any new license.

York Haven Power, 

Staff

$0 $0 $0d

27. Continue the licensing program for approximately 

300 recreational lots and terminate permits and remove 

from the licensing program existing recreational lots upon 

abandonment by the lessee, or when existing structures 

become damaged and are not replaced by structures 

conforming to all applicable federal, state, and local 

regulations.

York Haven Power, 

Staff

$0 $0 $0k
334

Enhancement/Mitigation Measure Entity

Capital 

Costa

(2014$)

Annual 

Costa

(2014$)

Levelized 

Annual Costb

(2014$)

28. Develop and implement an SMP to include: 

(a) summary of the purpose, goals, and objectives of the 

plan; (b) descriptions of shoreline use classifications, 

which identifies allowable and prohibited uses for existing 

and future use of the shoreline; (c) maps showing the 

shoreline classifications in relation to the project 

reservoir, project boundary, and various other features; 

(d) the lot lease and permitting program and guidelines 

developed to manage public uses; and (e) a monitoring 

and enforcement program; and provisions to update the 

plan every 10 years.

Staff $70,000 $2,410 $6,750m

29. Remove non-natural debris from the forebay and 

sluice remaining natural debris downstream after 

notifying the downstream PPL BI station.

York Haven Power, 

Settling Parties, Staff

$0 $0 $0d

30. Contribute $25,000 per year to the York Haven 

Conservation District or such other entity identified by 

Pennsylvania DEP for the purposes of debris removal in 

the lower Susquehanna River watershed.

York Haven Power, 

Settling Parties

$0 $25,000 $16,250g

Cultural Resources

31. Implement the HPMP filed with the Commission on 

December 28, 2012.

York Haven Power $0 $5,170 $3,360
335

Enhancement/Mitigation Measure Entity

Capital 

Costa

(2014$)

Annual 

Costa

(2014$)

Levelized 

Annual Costb

(2014$)

32. Implement York Haven’s proposed HPMP with the 

following modifications: (a) include a requirement to 

request landowner permission to access sites on private 

lands within the project boundary and evaluate them for 

listing on the National Register and for project impacts if 

project impacts are identified during monitoring activities;

(b) a plan and schedule to evaluate archaeological sites on 

York Haven lands in the project boundary for their 

National Register eligibility to ensure that any effects on 

sites owned by York Haven Power are fully considered in 

accordance with section 106; and (c) inclusion of two 

additional sites (36YO300, 36YO334) in the monitoring 

schedule, or clarification regarding why they were 

excluded. Implement the final plan.

Staff $20,000 $5,170 $4,840n
336

a All capital and annual costs were provided in 2011 dollars or 2013 dollars and were escalated to 2014 dollars for the purpose of 

this analysis. Annual costs typically include operational and maintenance costs and any other costs that occur on a yearly basis. 

All costs were provided by York Haven Power in its license application unless otherwise noted.

b All capital and annual costs are converted to equal annual costs over a 30-year period to give a uniform basis for comparing costs. c Staff estimated the cost; assumes implementation cost is included in construction cost for nature-like fishway below.

d Staff estimates no additional cost because this is a continuing measure. e Staff assumes that the cost of any lost energy is included in the lost energy estimate for the nature-like fishway below. 

f Staff estimated the cost.

g Cost provided by York Haven Power in the Settlement Agreement.

h No cost estimated for this measure as it is speculative and may not be needed.

i When inflows are under 3,000 cfs, the project is operated in a run-of-river mode (inflow = outflow), and if inflows were less than 

1,500 cfs, the York Haven Project would be unable to provide supplemental flows to ensure a flow of 1,500 cfs at the Brunner 

Island cooling water intake. Therefore, no cost could be estimated for this measure.

j Cost provided by York Haven Power in its additional information response filed with the Commission on March 15, 2013. 

Includes 500 MWh/year lost energy cost.

k Staff assumed that no additional cost would be required for this measure.

l Staff estimated the cost; annual cost assumes $50,000 in years 13 and 25 to update the plan. m Staff estimated the cost; annual cost assumes $20,000 in years 11 and 21 to update the plan. n Staff estimated the cost; capital cost for item (b) only.
337

Table 4-8. Cost of environmental mitigation and enhancement measures considered in assessing the environmental 

effects of continuing to operate the Muddy Run Project (Source: Staff and Exelon).

Enhancement/Mitigation Measure Entity

Capital Costa

(2014$)

Annual Costa

(2014$)

Levelized Annual 

Costb

(2014$)

Aquatic Resources

1. Develop a DO monitoring plan no earlier than 

November 1, 2027, with measures designed to ensure that 

the project does not violate DO standards.

Exelon, Staff $0 $0 $0c

2. Implement the minimum flow regime proposed by 

The Nature Conservancy and recommended by Interior 

for the Conowingo Project (effect on Muddy Run 

operation).

TNC, Interior $0 $2,062,630 $1,809,950d

3. Implement the Staff-recommended flow regime 

determined for Conowingo (effect on Muddy Run 

operation).

Staff $0 $21,490 $19,190e

4. Develop and implement FPOP for upstream and 

downstream fish passage and file with Pennsylvania DEP 

for review and approval by January 15, 2015.

Exelon, Staff $0 $0 $0f

5. Develop and implement a plan and schedule for a 

radio telemetry study or equivalent Tier II study of 

American shad passage and behavior within the Muddy 

Run Project boundary if resource agencies determine that 

operation of Muddy Run is causing the Holtwood Project 

to fail to meet its Tier I upstream American shad target 

prescribed in the certification for the Holtwood Project. 

Exelon, Staff $0 $0 $0g
338

Enhancement/Mitigation Measure Entity

Capital Costa

(2014$)

Annual Costa

(2014$)

Levelized Annual 

Costb

(2014$)

6. Implement the Eel Management Plan filed with the 

license application for the eel trap and truck program to

trap, hold, and transport American eels from the 

Conowingo Project to designated points in the 

Susquehanna River watershed until at least 2030 and then 

either continue the trap and truck program or construct a 

volitional eel passage facility at Conowingo dam.

Exelon $0 $0 $0h

7. Develop and implement a downstream eel passage 

plan to ensure safe and timely passage past the Muddy 

Run Project.

Exelon, Staff $0 $0 $0i

8. At all times, allow the project to be subject to 

inspection by representatives of FWS, to ensure 

compliance with any fish and wildlife protection, 

mitigation, and enhancements that may be contained in 

any Commission license issued for the project.

Interior $0 $0 $0f

Terrestrial Resources

9. Implement the Bald Eagle Management Plan filed 

with the license application. 

Exelon, 

Interior, Staff

$0 $1,150 $750

10. Implement the Bog Turtle Management Plan filed 

with the license application, which includes three 

components that Exelon would implement: (1) 

restriction of mowing in the wetland documented to 

support bog turtles; (2) invasive plant and woody plant 

control, particularly for reed canary grass; and (3) limits 

on public access to the wetland without advertising the 

reason.

Exelon, 

Interior, Staff

$0 $12,650 $8,240
339

Enhancement/Mitigation Measure Entity

Capital Costa

(2014$)

Annual Costa

(2014$)

Levelized Annual 

Costb

(2014$)

11. Before ground disturbance work begins, visit the 

FWS Chesapeake Bay Field Office and Pennsylvania 

Field Office websites and follow bog turtle and bald 

eagle management guidelines.

Interior, Staff $0 $0 $0f

12. Once every 10 years through the term of the license, 

evaluate all state and federally listed endangered and 

threatened species that may be present within the project 

boundary, and if the evaluation identified the presence, 

critical habitat, or critical dependence of endangered 

species, propose and implement a protection plan for 

each species.

Exelon $0 $70 $50j

13. Implement the osprey management policy, as 

described in the SMP.

Exelon, Staff $0 $0 $0k

14. Provide annual grants up to $450,000 split equally 

between the Lancaster County and York County 

Conservation Districts for the implementation of 

agricultural pasture and barnyard BMPs to control 

sediment loading to the Susquehanna River.

Exelon $0 $450,000 $292,960l

15. Provide $50,000 annually to Pennsylvania FBC to 

perform habitat improvement projects including the 

removal of small dams.

Exelon $0 $50,000 $32,550l

Recreation and Land Use 

16. Implement the Recreation Management Plan filed 

with the license application.

Exelon, Interior $0 $0 $0m
340

Enhancement/Mitigation Measure Entity

Capital Costa

(2014$)

Annual Costa

(2014$)

Levelized Annual 

Costb

(2014$)

17. At the Muddy Run Park: (1) replace Recreation 

Lake boat launching facilities and boat dock with an 

improved launching ramp and ADA-compliant dock; 

(2) implement shoreline erosion measures to improve 

runoff and stability in the vicinity of an ADA-compliant 

picnic area and boat rental dock; (3) replace an existing 

wood retaining wall with a sheet pile retaining wall to 

reduce shoreline erosion near the boat dock area; 

(4) upgrade the electric service to 50 campsites in the 

park, and monitor future need and upgrade additional 

sites when the demand occurs; (5) expand an existing 

playground near the visitor’s center with safety swings 

and three modular play structures suitable for younger 

children (tot lot); and (6) install a mulch safety surface, 

and construct a 2,000 square foot water spray park near 

the park entrance, along with paving resurfacing.

Exelon, Staff $2,045,000 $66,000 $194,510

18. At Wissler’s Run Park: (1) complete the 

replacement of the picnic pavilion, (2) designate and sign 

two additional ADA-compliant parking spaces near the 

picnic pavilion for compliance with standards set by the 

ADA Accessibility Guidelines for Buildings and 

Facilities, and (3) demolish the existing non-functioning 

fish cleaning station.

Exelon, Staff $16,000 $2,500 $2,810
341

Enhancement/Mitigation Measure Entity

Capital Costa

(2014$)

Annual Costa

(2014$)

Levelized Annual 

Costb

(2014$)

19. At Muddy Run WMA: (1) continue to lease the 

Muddy Run WMA to the Pennsylvania Game 

Commission for the management of the Muddy Run 

WMA to provide hunting opportunities in the area; and 

(2) erect and maintain FERC Part 8 signs at River Road 

and Furness Road WMA parking areas to identify the 

conditions of access to the site.

Exelon, Staff $0 $0 $0f

20. Implement Exelon’s proposed Recreation 

Management Plan with the addition of provisions to 

revise the plan in year 1 to include both recreation use 

monitoring and plan updates every 12 years in concert 

with every other the Form 80 reporting deadline.

Staff $12,000 $2,280 $2,370n

21. Implement the SMP filed with the license 

application consistent with Guidance for Shoreline 

Management Planning at Hydropower Projects.

Exelon $0 $0 $0o

22. Implement Exelon’s proposed SMP with the 

addition of a provision to review and update the plan 

every 10 years in consultation with appropriate agencies 

and other stakeholders.

Staff $12,000 $840 $1,440p

Cultural Resources

23. Prepare a cultural resources management plan if 

cultural materials are identified during project-related 

activities.

Exelon $8,000 $0 $590
342

Enhancement/Mitigation Measure Entity

Capital Costa

(2014$)

Annual Costa

(2014$)

Levelized Annual 

Costb

(2014$)

24. Prepare an HPMP in accordance with FERC and 

Advisory Council guidance to address potential project 

effects on historic properties including: (a) a detailed 

discussion the three sites identified during Phase IA 

cultural resources (36LA67, 36LA103, 36LA368) and 

two additional sites located outside of the project 

boundary (36LA70, 36LA47); (b) requirements for 

National Register evaluation of affected sites in 

consultation with the Pennsylvania SHPO; (c) 

requirements for formal National Register evaluation of 

the Muddy Run Pumped Storage Project facility; and 

(d) documentation of Native American consultation

Implement the HPMP.

Interior,

Staff $25,000 $45,000 $31,150q

a All capital and annual costs were provided in 2011 dollars and were escalated to 2014 dollars for the purpose of this analysis. 

Annual costs typically include operational and maintenance costs and any other costs that occur on a yearly basis. All costs were 

provided by Exelon in its license application unless otherwise noted.

b All capital and annual costs are converted to equal annual costs over a 30-year period to give a uniform basis for comparing costs. c No additional cost; continuing measure. d Cost based on energy estimates provided by Exelon in its response filed with the Commission on April 22, 2014; a loss of 134,800 

MWh in generation and a reduction of 175,000 MWh of pumping energy). e Staff estimates a loss of approximately 1,500 MWh in generation with a corresponding loss of 2,000 MWh of pumping energy. f Staff assumes no additional cost to implement this measure.

g No cost estimated for this measure because it is speculative and may not be needed. h No cost directly related to Muddy Run Project; cost would be covered by the Conowingo Project and is addressed below.

i No cost is estimated at this time as the cost would occur more than 10 years into the future, and any mitigation would be 

speculative and would depend on whether or not the target passage rates would be met.

i Staff estimated the cost; annual cost assumes $1,000 in years 10, 20, and 30.

j This measure is included in the SMP, and the cost is assumed to be part of the ongoing costs of the project.

k This measure and cost were provided by Exelon in its reply comments filed March 18, 2014.
343

l Cost of enhancements to individual recreation facilities are shown below. m Staff estimated the cost; annual cost assumes $50,000 in years 13 and 25 for updates to the plan. n The only element of the SMP that would have additional cost is the Bald Eagle Management Plan, and the costs of that plan are

listed separately above. o Staff estimated the cost; annual cost assumes $15,000 in years 11 and 21 for updates to the plan.

p Staff estimated the cost; capital cost for items (a), (b), and (c).
344

Table 4-9. Cost of environmental mitigation and enhancement measures considered in assessing the environmental 

effects of constructing and operating the Conowingo Project (Source: Staff and Exelon).

Enhancement/Mitigation Measure Entity

Capital Costa

(2014$)

Annual Costa

(2014$)

Levelized 

Annual Costb

(2014$)

Geologic and Soil Resources

1. Implement the Sediment Management Plan filed with 

the license application that identifies benchmarks and 

thresholds for action to address sediment issues that may 

affect project operation. 

Exelon $0 $9,550 $6,220

2. Conduct bathymetric surveys of Conowingo Pond at 

5-year intervals, starting in year 2016.

Exelon $0 $16,100 $10,480c

3. Implement Exelon’s proposed Sediment Management 

Plan with the addition of provisions to (1) incorporate 

Exelon’s proposed periodic dredging at the Conowingo 

Creek, Peters Creek (Peach Bottom Marina), and Broad 

Creek boat ramps, where sediments have been 

accumulating, to improve and maintain recreational 

boating access; and (2) include with the results of each 

bathymetric survey an analysis of any change in sediment 

deposition or scour in the pond from the previous 

survey(s).

Staff $0 $25,650 $16,700d
345

Enhancement/Mitigation Measure Entity

Capital Costa

(2014$)

Annual Costa

(2014$)

Levelized 

Annual Costb

(2014$)

Aquatic Resources

4. Operate the project with a normal range of operation 

of Conowingo Pond between the elevations 101.2 feet 

and 110.2 feet with a minimum elevation of 107.2 feet on 

weekends between Memorial Day and Labor Day, to 

meet recreational needs.

Exelon, Staff $0 $0 $0e

5. Provide minimum flow releases from the project as 

described below or a minimum flow equal to the 

discharge measured at the upstream USGS Marietta gage, 

whichever is less: (1) March 1-March 31: 3,500 cfs or 

natural inflow (as measured at the Marietta gage), if less; 

(2) April 1-April 30: 10,000 cfs or natural inflow, if less; 

(3) May 1-May 31: 7,500 cfs or natural inflow, if less; 

(4) June 1-September 14: 5,000 cfs or natural inflow, if 

less; (5) September 15-November 30: 3,500 cfs or natural 

inflow, if less; (6) December 1-February 28: 3,500 cfs 

intermittent (maximum 6 hours off followed by equal 

amount on).

Exelon $0 $0 $0e

6. Develop and implement a flow management plan. Interior $40,000 $0 $2,960f

7. Implement the TNC Flow Regime. Interior, TNC $0 $502,820 $329,130g
346

Enhancement/Mitigation Measure Entity

Capital Costa

(2014$)

Annual Costa

(2014$)

Levelized 

Annual Costb

(2014$)

8. Implement the Staff-recommended modified 

minimum flow regime that would enhance Exelon’s 

proposed minimum flows from December through 

February and in the first 2 weeks of June, as follows: 

September 15 – March 31: 3,500 cfs or natural inflow 

(as measured at the USGS Marietta gage No. 0157600), 

whichever is less; April 1 – April 30: 10,000 cfs or 

natural inflow, whichever is less; May 1 – June 15: 

7,500 cfs or natural flow, whichever is less; June 16 –

September 14: 5,000 cfs or natural inflow, whichever is 

less.

Staff $0 ($4,060) ($2,650)

h

9. Continue the DO enhancement at the project using 

the turbine venting systems on units 1-7 and the aerating 

runners on units 2 and 5, and continuously monitor DO 

levels from May 1 through October 1 at the Station 643 

location approximately 0.6 mile downstream of 

Conowingo dam.

Exelon, Staff $0 $0 $0e

10. Operate the east fish lift for upstream passage of 

American shad, river herring, and other migratory fishes, 

and the west fish lift for American shad egg collections 

and other research purposes.

Exelon, Staff $0 $0 $0e

11. Implement a preventative maintenance program for 

the east fish lift that would extend the useful life of the 

facility over the next license term. 

Exelon, Staff $0 $200,000 $130,200
347

Enhancement/Mitigation Measure Entity

Capital Costa

(2014$)

Annual Costa

(2014$)

Levelized 

Annual Costb

(2014$)

12. Use the project turbines as the route for downstream 

passage of American shad and river herring, based on 

studies that show high survival for fish passing through 

the turbines.

Exelon, Staff $0 $0 $0e

13. Modify the existing west fish lift as per Phase I of the 

Interior fishway prescription including a new west fish 

lift for both trap and trucking designed to truck 50,000 

adult shad per year and direct volitional upstream shad 

passage (two 6,500-gallon hoppers), an auxiliary water 

system of 2,600 cfs, a 5,000-foot zone of passage on the 

east and west shores of the tailrace below the dam, a 

maximum downramping rate of 20,000 cfs/hour, and 

channel modifications downstream to eliminate stranding 

in the spillway channel.

Interior $20,000,000 $0 $1,482,070f

14. Modify the existing east fish lift as per Phase II of the 

Interior fishway prescription including a stilling basin to 

allow 900-cfs attraction flow, as originally designed, 

relocation of the east fish lift entrance A to upstream of 

the Kaplan unit boils, construction of a new entrance D 

and collection gallery to east fish lift, along the Kaplan 

units connected to a new second hopper, and 

reconstruction of entrance B to east fish lift at 45 degrees 

to the river flow.

Interior $11,500,000 $0 $852,190f
348

Enhancement/Mitigation Measure Entity

Capital Costa

(2014$)

Annual Costa

(2014$)

Levelized 

Annual Costb

(2014$)

15. If the passage efficiency is not met by implementing 

Phase I (west lift) and II (east lift) of the Interior fishway 

prescription, make daily adjustments to minimum flows 

and turbine operations, construct an east fish lift auxiliary 

water supply of 4,325 cfs, and upgrade the east fish lift 

equipment to allow a 15-minute cycle time.

Interior $0 $0 $0i

16. Incorporate performance criteria into the new license 

where 80 percent of the shad that enter the project area 

must pass the project within 5 days, to be based on 

telemetry study of 150 shad per year for 3 years. If the 

goal is not met, initiate operational changes as specified 

by the agencies and test for 3 years using a telemetry 

study. If the goal is still not reached after 3 years of 

monitoring, make structural changes to the fish lifts as 

specified by the agencies, and test for an additional 3 

years using a telemetry study. If the goal is still not 

reached after 3 years, additional structural changes may 

be required, depending on the behavior of tagged shad.

Pennsylvania 

FBC

$300,000 $0 $22,230j

17. If warranted by the Pennsylvania FBC study above, 

complete the rebuild of the west fish lift to include 

additional attraction water and provision to expand to 

volitional passage if needed. Ultimately, fish passage 

facilities at Conowingo would need to pass a design 

population of 5 million fish, and fish lifts would be 

required on both sides of the tailrace.

Pennsylvania 

FBC

$0 $0 $0i
349

Enhancement/Mitigation Measure Entity

Capital Costa

(2014$)

Annual Costa

(2014$)

Levelized 

Annual Costb

(2014$)

18. If warranted by the Pennsylvania FBC study above, 

modify the east fish lift to include a larger hopper, 

increased attraction flow, and addition of a collection 

gallery in front of units 8-11.

Pennsylvania 

FBC

$0 $0 $0i

19. Reduce stranding of migratory fish by: (1) extending 

the retaining wall at the east end of the east fish lift; or 

(2) adding boulder fill in that area to prevent generation 

flow from flooding the spillway pool at high levels of 

generation; or (3) dredging a channel(s) from the 

spillway pool area to downstream areas to provide egress 

for stranded fishes.

Pennsylvania 

FBC

$1,000,000 $0 $74,100k

20. Conduct a study of the effect of gizzard shad on 

passage efficiency, capacity, and interference with 

American shad use of the lifts, and the recycling of 

gizzard shad in the west fish lift.

Pennsylvania 

FBC, Staff

$3,530 $0 $260l

21. Modify the west fish lift by replacing the existing 

hopper with a 1,500-gallon hopper, including associated 

structural, electrical, and mechanical upgrades. 

Staff $3,159,090 $0 $234,100m

22. Improve the west fish lift sorting and loading process 

to facilitate trap and truck operations, and purchase 

trucks, transport tanks, and associated equipment for the 

implementation of trap and truck operations.

Staff $979,340 $626,030 $480,120m

23. Conduct a feasibility study to determine if additional 

attraction flow is necessary at the west fish lift.

Staff $30,000 $0 $2,220f
350

Enhancement/Mitigation Measure Entity

Capital Costa

(2014$)

Annual Costa

(2014$)

Levelized 

Annual Costb

(2014$)

24. If the feasibility study determines that additional 

attraction flows are necessary and feasible at the west 

fish lift, install additional flow capacity.

Staff $0 $0 $0i

25. Restore the original east fish lift design for a 900-cfs 

attraction flow.

Staff $1,500,000 $0 $111,560f

26. Add a second 3,300-gallon hopper to the east fish lift 

in the space provided for the original design, and upgrade 

the electrical and mechanical equipment to allow a 

15-minute lift cycle.

Staff $1,683,470 $x $124,750n

27. After restoration of the 900-cfs attraction flow, 

conduct a 2-year effectiveness study.

Staff $100,000 $0 $7,410f

28. If the 2 years of effectiveness studies show poor 

attraction to the east fish lift at that flow, conduct a 

feasibility study of modifying the locations of entrances 

A and B.

Staff $0 $0 $0i

29. If the feasibility study shows that modifications to 

entrances A and B are technically feasible and would 

result in improved effectiveness, implement changes to 

the entrances.

Staff $0 $0 $0i

30. Construct a west bank American eel trap and 

transport facility that consists of a limited length eel ramp 

and a collection facility in the existing parking lot. 

Exelon, 

Interior, 

Pennsylvania 

FBC, Staff

$660,120 $604,340 $442,340o
351

Enhancement/Mitigation Measure Entity

Capital Costa

(2014$)

Annual Costa

(2014$)

Levelized 

Annual Costb

(2014$)

31. Construct a west bank American eel volitional 

passage near the west fish lift that consists of a full eel 

ramp with resting pools from the tailrace to the pond 

elevation sited near the west fish lift superstructure.

Exelon, 

Interior, Staff

$1,751,030 $206,610 $264,260o

32. Construct an east bank American eel trap and 

transport facility that consists of a limited length eel ramp 

and a collection facility in the existing access area below 

the non-overflow section of the dam.

Exelon, 

Interior, Staff

$642,560 $604,340 $441,040o

33. Construct an east bank American eel volitional 

passage facility (after 2030) that consists of a full eel 

ramp with resting pools from tailrace below spillbay 50 

to pond cored through the top of the dam.

Exelon, 

Interior, Staff

$1,162,190 $206,610 $203,140o

34. Participate in a trap and transport program for 

downstream eel passage, in cooperation with the other 

hydroelectric project operators on the lower Susquehanna 

River to trap and transport adult American eels from 

smaller tributaries upstream of York Haven dam.

Exelon, Staff $227,000 $286,200 $203,140

35. Continue a debris management program that includes 

clamming (with three gantry cranes with grapple 

attachments) to remove submerged debris from the area 

upstream of the powerhouse intakes and floating surficial 

debris in front of the powerhouse intakes, and the 

sponsorship of community-based clean-ups in the pond 

and downstream of the dam.

Exelon, Staff $0 $0 $0e
352

Enhancement/Mitigation Measure Entity

Capital Costa

(2014$)

Annual Costa

(2014$)

Levelized 

Annual Costb

(2014$)

Terrestrial Resources

36. Implement the Bald Eagle Management Plan filed 

with the license application. 

Exelon $0 $2,670 $1,740

37. Implement Exelon’s proposed Bald Eagle 

Management Plan with the addition of a provision to 

minimize recreation-related disturbance in proximity to 

roosting or foraging eagles.

Interior, Staff $0 $2,670 $1,740p

38. Develop and implement a bog turtle management 

plan.

Interior $0 $12,650 $8,240q

39. Develop and implement a northern map turtle 

protection plan.

Staff $30,000 $19,370 $14,830f

40. Develop and implement a waterfowl nesting 

protection plan in consultation with FWS that would 

(a) identify any project-related effects on waterfowl, such 

as flooding during nesting season; (b) identify which 

species of waterfowl are affected, if any; and, (c) if 

project-related effects are identified, establish appropriate 

protection or mitigation measures.

Interior, Staff $50,000 $25,000 $19,980f

41. Implement the osprey management policy, as 

described in the SMP.

Exelon, Staff $0 $0 $0r
353

Enhancement/Mitigation Measure Entity

Capital Costa

(2014$)

Annual Costa

(2014$)

Levelized 

Annual Costb

(2014$)

Recreation and Land Use

42. Maintain several public recreation facilities within 

the project boundary.

Exelon, Staff $0 $0 $0e

43. Implement the Recreation Management Plan filed as 

part of the license application to guide the operation and 

maintenance of Exelon’s recreation facilities, and the 

implementation of recreation facility enhancements 

outlined below. 

Exelon $0 $0 $0s

44. Implement improvements at Lock 13 to install a 

trailhead directional sign at the Lock 12 parking area, and 

clear vegetation from within the lock to provide an 

unobstructed view on each side of the lock structure to 

protect visitors.

Exelon, Staff $30,000 $500 $2,550

45. Implement improvements to Lock 15 to designate 

two ADA-compliant parking spaces in the existing 

parking area and install a dock on the shoreline near the 

picnic area to allow boaters to access the site; construct a 

concrete pad for portable restroom placement; stabilize 

the open shoreline area near the parking area to prevent 

erosion.

Exelon, Staff $60,000 $1,200 $5,230
354

Enhancement/Mitigation Measure Entity

Capital Costa

(2014$)

Annual Costa

(2014$)

Levelized 

Annual Costb

(2014$)

46. Implement improvements at Muddy Creek Boat 

Launch to designate two boat trailer spaces and one 

vehicle space for ADA-compliant parking in the existing 

parking lot; stabilize areas adjacent to the parking area to 

improve drainage and redirect flow away from the 

parking area and the river; install a sign providing 

information on the Conowingo dam canoe portage and 

the location of the portage take-out.

Exelon, Staff $72,000 $6,000 $9,240

47. Implement improvements to the Cold Cabin Boat 

Launch to improve access by designating a one-way 

directional traffic pattern through the site and 

constructing parking for 11 vehicles (five boat trailer and 

six vehicle spaces), including two ADA-compliant

spaces; reinforce existing boat ramp to prevent 

undermining of the ramp and install a boat dock; install a 

sign providing information on the Conowingo dam canoe 

portage and the location of the portage take-out; provide 

two ADA-compliant picnic tables; install a concrete pad 

for the placement of two portable restrooms 

(one ADA-compliant, one standard).

Exelon, Staff $210,000 $2,500 $17,190
355

Enhancement/Mitigation Measure Entity

Capital Costa

(2014$)

Annual Costa

(2014$)

Levelized 

Annual Costb

(2014$)

48. Implement improvements to Dorsey Park to rebuild 

both boat ramps at Dorsey Park; designate one 

ADA-compliant boat trailer space and one ADA vehicle 

space in the existing lot; install a concrete pad for three 

portable restrooms (one ADA-compliant, two standard); 

install a sign providing information on the Conowingo 

dam canoe portage and the location of the portage takeout.

Exelon, Staff $274,000 $18,000 $32,020

49. Implement improvements to the Conowingo Creek 

boat launch to designate one ADA-compliant parking 

space in the existing parking area; stabilize a roadside 

ditch along Mt. Zoar Road and construct a stone-lined 

drainage ditch along the south side of the parking lot to 

redirect runoff from the parking lot and boat ramp; install 

a sign providing information on the Conowingo dam 

canoe portage and the location of the portage take-out.

Exelon, Staff $56,000 $3,600 $6,490

50. Implement improvements to the Glen Cove Marina 

to expand the marina by adding seven additional trailer 

spaces (one ADA-compliant) and 11 vehicle (two 

ADA-compliant) spaces; repair the marina’s bulkhead 

wall.

Exelon, Staff $220,000 $1,700 $17,410

51. Implement improvements at Funk’s Pond to 

designate one ADA-compliant parking space in the 

existing parking area.

Exelon, Staff $300 $500 $350
356

Enhancement/Mitigation Measure Entity

Capital Costa

(2014$)

Annual Costa

(2014$)

Levelized 

Annual Costb

(2014$)

52. Implement improvements to Line Bridge to perform 

shoreline erosion control and stabilization at this 

unimproved carry-in boat access area.

Exelon, Staff $9,000 $500 $490

53. Implement improvements at Conowingo swimming 

pool to install an ADA-compliant access facility at the 

swimming pool and an ADA-compliant access ramp at 

the wading pool.

Exelon, Staff $173,000 $3,500 $15,100

54. Implement improvements at Conowingo dam 

overlook to reopen the facility and designate three 

ADA-compliant vehicle spaces in the existing parking 

lot; demolish the existing pavilion and replace it with a 

new 24-foot by 24-foot wooden pavilion; remove 

pavement from the easterly corner of the existing paved 

parking area, loam and seed, and install three 

ADA-compliant pathways and picnic tables; install 

security fencing around the site to restrict unobstructed 

views from the pavilion and picnic area.

Exelon, Staff $232,000 $3,000 $19,150
357

Enhancement/Mitigation Measure Entity

Capital Costa

(2014$)

Annual Costa

(2014$)

Levelized 

Annual Costb

(2014$)

55. Implement improvements to Fisherman’s Park and 

Shures Landing to widen the access road to the facility 

by 3 to 5 feet to allow construction of 12-foot-wide lanes; 

construct a retaining wall along the easterly 250 feet of 

the existing parking area along the access road; designate 

five additional ADA-compliant parking spaces in the 

existing parking lot; widen the access road leading to 

Shures Landing by 4 feet along the eastbound lane for 

320 feet; and widen the access road from the trailhead 

parking north of the retaining wall by 2 feet; construct an 

additional 13-space parking area near the Lower 

Susquehanna Heritage greenway trailhead at the 

southerly end of Fisherman’s Park; demolish the existing 

hard surface boat launch and asphalt access at Shure’s 

Landing and place stone fill next to the existing wall 

down to existing grade along the Susquehanna River 

shoreline; and construct a new 20-foot-wide hard surface 

carry-in boat launch with a floating dock and breakwater 

at Shure’s Landing to replace the existing launch area.

Exelon, Staff $1,194,000 $2,900 $90,370

56. Implement improvements at Peach Bottom access to 

construct a small (four vehicle) road-side parking area 

near the existing informal boat launch area south of 

Peter’s Creek; install a sign providing information on 

Conowingo dam canoe portage and the location of the 

portage take-out.

Exelon, Staff $20,000 $1,800 $2,650
358

Enhancement/Mitigation Measure Entity

Capital Costa

(2014$)

Annual Costa

(2014$)

Levelized 

Annual Costb

(2014$)

57. Implement Exelon’s proposed Recreation 

Management Plan with the addition of provisions to 

revise the plan in year 1 to include both recreation use 

monitoring and plan updates every 12 years in concert 

with every other the Form 80 reporting deadline.

Staff $40,000 $2,280 $4,450 t

58. Open the catwalk (at least on a limited basis) for 

angling with new security gate and check in/out 

procedures for anglers.

Staff $1,908,000 $0 $141,390 u

59. Conduct dredging at the Conowingo Creek, Peach 

Bottom Creek, and Broad Creek boat ramps.

Exelon, Staff $6,653,230 $0 $493,030 v

60. Implement the SMP filed with the license application 

including specific measures and policies related to 

shoreline vegetation management and erosion control, 

woody debris management, game species management, 

sensitive natural resource protection, recreation use, 

BMPs for controlling sediment introduction from lands 

within the project boundary, and use of project lands.

Exelon, 

Interior

$0 $0 $0 w

61. Implement Exelon’s proposed SMP with the addition 

of a provision to update the SMP every 10 years in 

consultation with appropriate agencies and interested 

stakeholders.

Staff $12,000 $840 $1,440 x
359

Enhancement/Mitigation Measure Entity

Capital Costa

(2014$)

Annual Costa

(2014$)

Levelized 

Annual Costb

(2014$)

62. Revise the project boundary by removing lands that 

are not necessary for the safe and efficient operation and 

maintenance of the project or for other specified project 

purposes, such as public recreation or protection of 

environmental resources.

Exelon, Staff $0 $0 $0 c

Cultural Resources 

63. Implement the HPMP filed with the Commission on

December 28, 2012.

Exelon $95,000 $21,150 $20,810
360

Enhancement/Mitigation Measure Entity

Capital Costa

(2014$)

Annual Costa

(2014$)

Levelized 

Annual Costb

(2014$)

64. Revise and implement Exelon’s proposed HPMP to 

include: (a) a revised APE to include the narrow strip of 

land in the current project boundary extending

downstream from Spencer Island along the west side of 

the river to Havre de Grace; (b) a discussion of all 48 

sites and 27 historic structures identified to date within 

the project APE or an explanation of why they are not 

considered; (c) a correction to identify the Susquehanna 

and Tidewater Canal and Columbia & Port Deposit 

Railroad eligible for listing; (d) requirements to inventory 

any lands within the revised APE, evaluate identified 

cultural resources for eligibility, and address potential 

effects before sale or transfer of those lands; (e) a 

requirement to make good faith effort to obtain access to 

private property to conduct studies if project effects on 

cultural resources on private lands are identified; (f) a 

revised list of project activities involving the Conowingo 

Project that can be completed without Maryland SHPO 

review; (g) a process for assessing project-related 

ground-disturbing activities to determine whether or not 

archaeological sites would be affected, particularly in 

areas that have not had archaeological surveys; 

(h) requirements to ensure confidentiality of cultural 

resources location information during implementation of 

public outreach programs; and (i) a description of 

project-related activities that would require consultation 

with the Delaware Nation and the Onondaga Nation in 

accordance with section 106 of the NHPA and 

documentation of Native American consultation.

Staff $105,000 $45,000 $37,080 f
361

a All capital and annual costs were provided in 2011 dollars and were escalated to 2014 dollars for the purpose of this analysis. 

Annual costs typically include operational and maintenance costs and any other costs that occur on a yearly basis. All costs were 

provided by Exelon in its license application unless otherwise noted.

b All capital and annual costs are converted to equal annual costs over a 30-year period to give a uniform basis for comparing costs. c Staff assumed that no additional cost would be required for this measure.

d The cost of the staff alternative plan would be the same as the cost of the proposed Sediment Management Plan plus the cost of the 

bathymetric surveys, with no additional cost to include the two additional provisions. The cost of the dredging is included with 

item 59 under Recreation. e No additional cost; continuing measure.

f Staff estimated the cost. g Cost based on energy estimates provided by Exelon in its response filed with the Commission on April 22, 2014; gain of 

12,400 MWh of generation. h Staff estimates a gain of 100 MWh for this measure.

i No cost estimated for this measure as it is speculative and may not be needed.

j Cost estimated by Staff assumes $100,000 per year in years 1-3 for the initial telemetry study; no cost was estimated beyond 

year 3 as the phase after year 3 is speculative and may not be needed.

k Cost estimate by Staff is a preliminary ballpark estimate. Actual cost would depend on the alternative selected and the design of 

the alternative.

l Staff estimated the cost; assumes $50,000 in year 3. m Cost provided by Exelon in study report Revised Study Plan (RSP) 3.9, Biological and Engineering Studies of East and West Fish 

Lifts. n Cost provided by Exelon in study report RSP 3.9, Biological and Engineering Studies of East and West Fish Lifts, for second 

hopper plus $200,000 estimated by Staff for electrical and mechanical upgrades. o Cost estimated by Exelon in study report RSP 3.3, Biological and Engineering Studies of American Eel. p Staff estimates the slight differences between Interior’s prescribed measure and Exelon’s proposed plans would not require 

additional costs to implement the differences.

q Staff assumed that the Muddy Run Bog Turtle Management Plan could be adapted for Conowingo and that the implementation 

costs would be comparable to the costs estimated by Exelon for Muddy Run. r This measure is included in the SMP, and the cost is assumed to part of the ongoing costs of the project. s Cost of enhancements to individual recreation facilities are shown below.

t Staff estimated the cost; annual cost assumes $50,000 in years 13 and 25 for updates to the plan. u The cost was provided by Exelon in study RSP 3.32, Re-evaluate the Closing of the Catwalk to Recreational Fishing, filed with 

the Commission on January 31, 2012. Note that the report was filed as a Critical Energy Infrastructure Information document, 
362

which is not directly available to the public. If the catwalk is reinforced instead of being replaced, the cost would be $1,484,000. 

In addition, Exelon based its cost estimates on a 12 hours per day and 365-day per year opening. If the catwalk is only open on a 

limited basis, the costs would be significantly less. v Cost provided by Exelon in its March 25, 2014, filing. w The only element of the SMP that would have additional cost is the Bald Eagle Management Plan, and the costs of that plan are 

listed separately above. x Staff estimated the cost; annual cost assumes $15,000 in years 11 and 21 for updates to the plan.
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5.0 CONCLUSIONS AND RECOMMENDATIONS

5.1 COMPREHENSIVE DEVELOPMENT AND RECOMMENDED 

ALTERNATIVE 

Sections 4(e) and 10(a)(1) of the FPA require the Commission to give equal 

consideration to the power development purposes and to the purposes of energy 

conservation; the protection, mitigation of damage to, and enhancement of fish and 

wildlife; the protection of recreational opportunities; and the preservation of other aspects 

of environmental quality. Any license issued shall be such as in the Commission's 

judgment will be best adapted to a comprehensive plan for improving or developing a 

waterway or waterways for all beneficial public uses. This section contains the basis for, 

and a summary of, our recommendations for relicensing the York Haven, Muddy Run, 

and Conowingo projects. We weigh the costs and benefits of our recommended 

alternative against other proposed measures.

Based on our independent review of agency and public comments filed on these 

projects and our review of the environmental and economic effects of the proposed 

projects and their alternatives, we selected the staff alternative as the preferred alternative

for each of the projects. In each case, the staff alternative includes elements of the 

applicants’ proposals, resource agency recommendations, and some additional measures. 

We recommend these alternatives because: (1) issuance of new hydropower licenses by 

the Commission would allow York Haven Power and Exelon to operate the projects as 

economically beneficial and dependable sources of electrical energy for their customers; 

(2) generation from the York Haven, Muddy Run, and Conowingo projects, with total 

installed capacities of 19.62, 800.25, and 574.54 MW, respectively, comes from a 

renewable resource that does not contribute to atmospheric pollution; (3) the public 

benefits of these alternatives would exceed those of the no-action alternatives; and (4) the 

recommended measures would protect and enhance water, fish and wildlife resources, 

protect cultural resources, and provide improved recreation opportunities at the projects.

Finally, for the reasons outlined in the following sections, we recommend that 

certain conditions preliminarily prescribed by Interior not be included in the staff 

alternative. The conditions that we are not including pertain to certain measures in 

Interior’s fishway prescription for the Muddy Run and Conowingo projects. We 

recognize, however, that, if finalized, the Commission must include these conditions in 

any license due to their mandatory nature.

In the following sections, we make recommendations as to which environmental 

measures proposed by the applicants or recommended by agencies or other entities 

should be included in any new license issued for the projects. In addition to the 

applicants’ proposed environmental measures, we recommend additional staff-developed 

environmental measures to be included in any new license issued for the projects, and we 

describe these requirements in the draft license articles in Appendix A. 
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5.1.1 York Haven Project

5.1.1.1 Measures Proposed by York Haven Power

Based on our environmental analysis of York Haven Power’s proposal in 

section 3, Environmental Effects, and the costs presented in section 4, Developmental 

Analysis, we conclude that the following environmental measures proposed by York 

Haven Power would protect and enhance environmental resources and would be worth 

the cost. Therefore, we recommend including these measures in any license issued for 

the project. We discuss any modification to York Haven Power’s proposed measures 

below under Measures Recommended by Staff for the York Haven Project.

Under the terms of the Settlement Agreement, York Haven Power would 

implement the following environmental measures at the York Haven Project:

• Develop an erosion and sediment control plan for construction of the 

nature-like fishway.

• Continue to operate and maintain the existing east channel upstream 

fishway for upstream fish passage.

• Continue the current downstream juvenile American shad passage protocol 

that calls for the operation of units 1-6 (Kaplan and propeller units) to be 

first online and last offline during the juvenile shad downstream migration 

period (which typically is from October 1 through November 30), and 

opening the forebay sluice gate at specific times for downstream fish 

passage. If river flows exceed the capacity of units 1-6, unit 14 would be 

operated, and if flows exceed the capacities of units 1-6 and 14, units 7-13 

and 15-30 would be operated in ascending order.

• Provide a year-round, continuous, minimum-flow from the project of 

1,000 cfs and an average daily minimum flow of 2,500 cfs, or inflow, 

whichever is less to protect and enhance aquatic resources downstream of 

the project. 

• Continue to operate the project in a run-of-river mode when inflow to the 

project is less than 3,000 cfs. 

• Pass about 370 cfs through the forebay sluice gate for 1 or 2 hours in the 

morning during weekdays if river flows exceed the sum of the turbine 

hydraulic capacity, flows through the nature-like fishway, once constructed, 

flows through the east channel, and flows (if any) over the main dam from 

May 1 through June 30 to facilitate downstream passage of post-spawning 

adult American shad, and any day that river flow exceeds the combined 

hydraulic capacity during the fall American shad emigration period to 

facilitate downstream passage of juvenile American shad. 
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• Pass about 370 cfs through the forebay sluice gate between the hours of 

5 p.m. and 11 p.m. during the entire fall juvenile American shad passage 

period to facilitate downstream passage of juvenile American shad.

• Develop designs within 4 years of license issuance for: (1) removal of 

obstructions in or deepening of the downstream plunge pool for the forebay 

sluice gate, and (2) a chute structure to convey flows beyond the roadway 

on the downstream side of the cable alley structure to protect outmigrating 

juvenile and adult American shad passing into the downstream plunge pool.

• Cooperate with resource agencies and other interested parties to conduct a 

lower Susquehanna River downstream eel migration study including 

monitoring silver eels at the project and providing $25,000 to support the 

study.

• Conduct a site-specific silver eel route of passage study and a survival 

study as described in appendices G and H of the Settlement Agreement 

including the potential for providing $50,000 to resource agencies for 

collection and tagging of silver eels at upstream locations.

• Conduct a downstream eel passage improvement study if downstream eel 

passage goals are not achieved with provisions for subsequent monitoring 

and adjustments. 

• Construct, operate, and maintain a nature-like fishway in the vicinity of the 

apex of the main dam and Three Mile Island in compliance with design 

criteria specified in appendix A of the Settlement Agreement.

• Prior to construction of the proposed nature-like fishway:

o Provide a minimum flow of 2,000 cfs at east channel dam and a 

spillage flow of 4,000 cfs at the main dam during the American shad 

upstream passage season when the east channel fishway is in 

operation.

o After the American shad upstream passage season until the end of 

the resident fish passage season maintain a minimum flow of 400 cfs 

in the east channel downstream from the east channel fishway during 

the period that the east channel fishway is operated to allow 

upstream passage of resident fish species, per the June 2010 Consent 

Order and Agreement between York Haven Power and 

Pennsylvania DEP.
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o Conduct vegetation surveys, wetlands delineations, invasive species 

surveys, rare species surveys, bog turtle habitat assessments, and 

bald eagle surveys in the area of the nature-like fishway.

89 

• After construction of the nature-like fishway:

o Conduct American shad upstream passage effectiveness studies 

using radio telemetry beginning during the second year of the 

nature-like fishway operation. If the project area passage success 

criterion is not achieved, York Haven Power would implement 

corrective measures, followed by two additional years of radio 

telemetry studies to confirm achievement of the project area passage 

success criterion.

o Conduct a juvenile American shad headrace turbine avoidance study 

consistent with design criteria included in appendix D of the 

Settlement Agreement.

o If the juvenile American shad headrace turbine avoidance goals are 

not achieved, implement measures that would enhance the 

effectiveness of downstream passage and conduct a supplemental 

juvenile American shad headrace turbine avoidance study within 2 

years of implementing the measures. 

o Provide an average daily minimum flow in the east channel below 

east channel dam of 267 cfs year round to protect aquatic resources 

in the east channel and provide a minimum passage flow for fish 

ascending the east channel and using the east channel fishway.

o Provide a minimum of 5 percent of the river flow through the 

nature-like fishway during the American shad upstream passage 

season such that when inflows to the project are between 5,000 and 

150,000 cfs, total flow through the nature-like fishway would range 

from about 1,000 to 7,500 cfs, depending on inflow. 

o Provide a minimum flow of 200 cfs through the nature-like fishway 

outside of the American shad upstream passage season when the 

river elevation is at the crest of the main dam. 

o When flows exceed the hydraulic capacity of all available generating 

units, and to the extent controllable by York Haven Power, manage 

flows to maximize flow over the main dam and the nature-like 

 

89 These proposed measures cited in the explanatory statement accompanying the 

Offer of Settlement would be implemented prior to the construction of the nature-like 

fishway. 
367

fishway to provide attraction flow to the vicinity of and from the 

nature-like fishway to maximize fishway effectiveness.

• To prevent a buildup of debris that could affect project and fish passage 

operations, remove non-natural debris from the forebay and sluice 

remaining natural debris downstream, after notifying the downstream PPL 

Brunner Island Station. 

In addition to those measures specified in the Settlement Agreement, York Haven 

Power also proposes to implement the following measures included in its final license 

application:

• Maintain existing project recreation facilities on four islands in Lake 

Frederic and the project recreation facilities at the powerhouse, including an 

existing portage trail for canoeists and fishing access along the downstream 

face of the powerhouse, and consult with the resource agencies on 

recreation resources and management strategies every 10 years after the 

effective date of any new license. 

• Continue the current permitting program for the approximately 300 

recreational lots located within the project boundary, but terminate permits 

and remove lots from the program if structures are abandoned by the lessee, 

or when existing structures become damaged and are not replaced by 

conforming structures. 

• Implement the HPMP filed with the Commission on December 28, 2012, to 

manage project effects on historic properties eligible for listing on the 

National Register. 

5.1.1.2 Additional Measures Recommended by Staff for York Haven

We recommend the York Haven Power-proposed measures described above with 

the following additions or modifications: 

• Develop a recreation management plan that provides for York Haven’s 

proposed maintenance of its existing recreation facilities with additional 

provisions to update the plan every 12 years consistent with every other 

Form 80 reporting period deadline, include safety measures during 

construction of the nature-like fishway, and continue the licensing program 

for approximately 300 recreational lots within the project boundary, and 

implement revisions to the program to allow for the termination of permits 

and removal of lots from the program if structures are abandoned by the 

lessee, or when existing structures become damaged and are not replaced 

by conforming structures. 
368

• Develop an SMP that includes specific measures and policies related to 

shoreline management at the project and include a provision to update the 

plan every 10 years. 

• Modify York Haven’s proposed HPMP with the following additional 

provisions: (a) include a requirement to request landowner permission to 

access sites on private lands within the project boundary and evaluate them 

for listing on the National Register and for project impacts if project 

impacts are identified during monitoring activities; (b) a plan and schedule 

to evaluate archaeological sites on York Haven lands within the project 

boundary for their National Register eligibility to ensure that any effects on

sites owned by York Haven Power are fully considered in accordance with 

section 106; and (c) inclusion of two additional sites (36YO300, 36YO334) 

in the monitoring schedule, or clarification regarding why they were 

excluded.

Below we discuss the rationale for recommending proposed measures, modified 

measures, and additional staff measures for the York Haven Project. 

Erosion and Sediment Control Plan 

York Haven Power, in the explanatory statement filed with the Settlement 

Agreement, states that it would develop and implement an erosion and sediment control 

plan prior to constructing the nature-like fishway. This measure, however, is not 

included in the Settlement Agreement. To protect water quality during construction, we 

recommend the development and implementation of an erosion and sediment control plan 

for the fishway construction as a condition of any license issued because it would 

minimize effects on the river’s aquatic habitat. We estimate that the levelized annual cost 

of implementing this plan would be $370 and conclude the benefits of protecting the 

aquatic habitat justify the cost.

Instream Flows and Flow Distribution

York Haven Power is proposing to continue its current continuous minimum flow 

of 1,000 cfs from the powerhouse and an average daily flow of not less than 2,500 cfs; if 

inflow to the impoundment is less than these amounts, discharge from the project would

not be less than the inflow. Under the Settlement Agreement, York Haven Power would 

provide further refinements to the minimum and other project flows, including 

redistribution of flows for enhancement of upstream and downstream fish passage as 

described below and summarized as follows: (1) operate the project in a run-of-river 

mode when inflow to the project is less than 3,000 cfs; (2) prior to completion of the 

nature-like fishway (see below), provide a minimum flow of 2,000 cfs at the east channel 

dam during the American shad upstream passage season and 400 cfs during the resident 

fish passage season, and a spillage flow of 4,000 cfs at the main dam during the shad 

upstream passage season when the east channel fishway is in operation; (3) after 
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completion of the nature-like fishway, reduce the east channel minimum flow to 267 cfs 

year-round, reduce the flow at the main dam to a minimum of 1,000 cfs (through the 

nature-like fishway and supplemental attraction flow channel) during the shad upstream 

passage season, and further reduce the main dam flow (through the nature-like fishway) 

to 200 cfs during the resident fish passage season; (4) provide at least 5 percent of river 

flow through the nature-like fishway and supplemental attraction flow channel when 

flows entering the project during the American shad upstream passage season are 

between 5,000 and 150,000 cfs; (5) when flows exceed the hydraulic capacity of all 

available generating units, manage flows to maximize flow over the main dam and the 

nature-like fishway; and (6) pass about 370 cfs through the forebay sluice gate at 

specified times for downstream passage of adult and juvenile shad (see below). The main 

purpose of this flow redistribution is to shift the emphasis of upstream passage to the 

nature-like fishway, while still providing passage through the east channel fishway. 

Overall, flows past the project would not be substantially different than current 

conditions, and because of the low hydraulic capacity of the project, would on average 

continue to spill about 60 percent of the time. The flow redistribution to enhance fish 

passage should act to guide fish to the new main route for upstream fish passage, the 

nature-like fishway. We estimate that the proposed minimum flows and flow 

redistribution can be provided at no additional cost.

Nature-Like Fishway

York Haven Power proposes to construct a nature-like fishway in the vicinity of 

the apex of the main dam and Three Mile Island, consistent with the design criteria set 

forth in appendix A of the Settlement Agreement. While the east channel fishway would 

remain in operation, the nature-like fishway would become the main route for upstream 

passage at the project. In conjunction with the installation of the nature-like fishway, 

York Haven Power proposes to modify project flow releases that would provide fish 

passage attraction flows to the nature-like fishway and establish this fishway as the 

primary fish passage facility and the existing east channel fishway as the secondary 

passage facility. The proposed flow release changes, as described above, would 

redistribute minimum flow releases among the various project flow release structures 

(east channel spillway, east channel fishway, nature-like fishway, main dam, and 

powerhouse). The overall minimum flow releases downstream of the project would not 

change. The nature-like fishway would also be designed so that a full range of 

anadromous, catadromous, and resident species could use the facility for upstream 

passage. In addition, York Haven Power proposes to conduct vegetation surveys, 

wetlands delineations, invasive species surveys, rare species surveys, bog turtle habitat

assessments, and bald eagle surveys in the area of the nature-like fishway prior to 

construction. These surveys, done in consultation with the state resource agencies and 

FWS, would identify if any terrestrial resource protection measures would be required 

prior to construction. In section 3.3.2.2, Water Resources, Environmental Effects, under 

Upstream Fish Passage, we conclude that the proposed location and design of the naturelike fishway would be a substantial enhancement of existing upstream fish passage 
370

facilities and should improve fish passage effectiveness at the project. We estimate the 

annual levelized cost of conducting the pre-construction surveys would be $3,700 and the 

annual levelized cost constructing the nature-like fishway would be $549,100, and the 

benefit to Susquehanna River migratory species would be worth the cost.

Fish Passage Effectiveness Study

York Haven Power proposes to conduct an effectiveness study, using radio-tagged 

shad, beginning in year 2 of the nature-like fishway operation and continuing for 2 years. 

We agree with the need for an effectiveness study for a new fish passage facility, and 

especially for the novel natural-like design, which has not been constructed at any 

hydroelectric project on a major Atlantic coast river. The establishment of passage 

targets and success criteria, used properly, allow a determination of whether the fishway 

is operating as designed. Caution is needed, however, because many factors beyond 

engineering design and hydraulics may affect effectiveness, particularly for shad. For 

example, York Haven Power’s 2010 radio telemetry study found that only 70 percent of 

the tagged fish released at the downstream Safe Harbor Project reached the York Haven 

Project area, indicating that some fish used the habitat between the projects, or had no 

motivation to continue upstream migration to York Haven. The Settlement Agreement 

acknowledges this issue, and while the upstream shad passage target is that at least 

75 percent of the shad counted at the downstream Safe Harbor Project be passed above 

York Haven dam, compliance is based on the project area passage success criteria that 

85 percent of the shad that reach the York Haven Project area successfully pass upstream 

of the project. This properly recognizes that York Haven Power has no control over 

whether or not shad reach the project area, and the proposed fish passage effectiveness 

study would provide additional information on the behavior of shad approaching and 

ultimately passing the York Haven Project. We estimate that the proposed fish passage 

effectiveness study would have a levelized annual cost of $16,280, and would be worth 

the cost to ensure that the proposed fishway is effective for upstream passage. 

Downstream Fish Passage

York Haven Power is proposing to continue its downstream fish passage protocol 

that it has been implementing for the past several years. This includes: (1) when river 

flow is less than the project hydraulic capacity, prioritization of powerhouse generation 

through units 1 through 6 (propeller units) on a first-on/last-off basis, followed by units 7 

through 20 (Francis units); (2) opening the forebay sluice gate located in the lower 

forebay corner adjacent to unit 1 for downstream fish passage; and (3) using temporary 

lighting above the forebay sluice gate to aid in attracting alosine species to the sluice gate 

entrance. At river flow greater than project hydraulic capacity, which occurs about 60 

percent of the time, downstream fish passage occurs via spillage over the dam. Under the 

Settlement Agreement, York Haven Power proposes a suite of additional measures for 

downstream passage, including: (1) passing about 370 cfs through the forebay sluice gate 

for 1 or 2 hours in the morning during weekdays if river flows exceed the sum of the 
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turbine hydraulic capacity, flows through the nature-like fishway, once constructed, flows 

through the east channel, and flows (if any) over the main dam from May 1 through 

June 30 to facilitate downstream passage of post-spawning adult American shad, and 

during the juvenile American shad downstream passage period to facilitate downstream 

passage of juvenile American shad; (2) passing about 370 cfs through the forebay sluice 

gate between the hours of 5 p.m. and 11 p.m. during the entire juvenile American shad 

passage period to facilitate downstream passage of juvenile American shad; and 

(3) developing designs within 4 years of license issuance for: (a) removal of obstructions 

in or deepening of the plunge pool below the forebay sluice gate, and (b) a chute structure 

to convey flows beyond the roadway on the downstream side of the cable alley structure 

to protect outmigrating juvenile and adult American shad that pass into the downstream 

plunge pool. York Haven Power is also proposing to conduct studies on the downstream 

migration of juvenile shad, once the nature-like fishway is in operation, including a 

juvenile shad headrace turbine avoidance study consistent with design criteria included in 

appendix D of the Settlement Agreement. If the juvenile shad headrace turbine 

avoidance goals are not achieved, York Haven Power would implement measures that 

would enhance the effectiveness of downstream passage and conduct a supplemental 

juvenile shad headrace turbine avoidance study within 2 years of implementing the 

measures. All of these measures would enhance downstream fish passage survival at 

York Haven, would ensure that downstream passage survival goals are met, and should 

be implemented by York Haven Power. We estimate that these measures would have a 

levelized annual cost of $1,480, while the juvenile shad headrace turbine avoidance study 

would have a levelized annual cost of $3,700. These measures would be worth the cost 

to ensure that survival goals are met. 

American Eel Study

York Haven Power proposes to cooperate with resource agencies and other 

interested parties to conduct a lower Susquehanna River downstream American eel study 

including site-specific silver eel route of passage and survival studies. American eels do 

not currently occur in the project area in any numbers, with those present being the result 

of experimental upstream stockings. Because upstream passage at downstream dams, 

discussed under the Muddy Run and Conowingo projects below, would require several 

years to develop, it would be many years before upstream migrating eels arrive in the 

York Haven Project area through volitional migrations. If trap and trucking of eels is 

implemented at Conowingo as proposed, it is likely that eels would be trucked upstream 

of York Haven within 2 to 3 years of license issuance and would remain in the river for 

10 to 20 years before reaching the silver eel phase and out-migrating to the ocean. The 

nature-like fishway and the low-head configuration of the dam would likely provide for 

adequate upstream passage once upstream migrating eels arrive at the project, either from 

trucking of eels to locations downstream of York Haven, or any future volitional passage 

at downstream projects. Once sufficient numbers of silver eels are migrating downstream 

at York Haven, downstream passage measures should be implemented to ensure safe and 

timely downstream passage. The Settlement Agreement includes provisions for the 
372

eventual downstream passage of eels at the project, including studying the migratory 

pathways at the project and survival through the turbine generators, and then 

implementing protective measures if needed. These provisions of the Settlement 

Agreement would adequately protect downstream migrating eels once they arrive at the 

project. We estimate that the annual levelized cost of the route of passage study and 

survival study would be $3,700 each, and the benefit to migrating eels would be worth 

the cost. 

Recreation Management 

York Haven Power proposes a number of operational and maintenance activities 

related to recreation, such as maintaining canoe portage trails, fishing access, and public 

boat access areas and consulting with the stakeholders on recreation resources about 

recreation management and strategies every 10 years after license issuance. However, 

York Haven Power does not propose a recreation management plan. Project recreation 

sites, including the four islands in Lake Frederic, and sites that are leased or managed by 

others, receive regular use by visitors at project lands and waters. The Commission 

requires these facilities to be maintained and available for public recreational uses 

throughout the term of any future license. Development of a formal recreation 

management plan that includes a facility inventory with ownership and management 

responsibilities for each site, as well as measures to provide for periodic monitoring, 

would ensure the recreation facilities and sites are managed to meet use and demand over 

the term of any future license. Including a provision to address human safety concerns 

during construction of the nature-like fishway would ensure the safe access and use of 

existing facilities that might be affected by the construction activity. Consultation with 

the resource agencies, counties, and other interested stakeholders in the project, including 

Pennsylvania FBC and Pennsylvania DCNR, in the development of the plan would 

ensure that stakeholder interests are represented and the facilities meet regional needs. 

We also agree with York Haven Power’s proposal to include the entirety of the Lock 15 

facility within the project boundary because the site is associated with the project’s East 

Shore Boat Launch. The benefit to recreation resources of the development of a 

recreation management plan would be worth the estimated levelized annual cost 

of $3,710. 

Shoreline Management

Aquatic, recreational, and natural resources exist along the shorelines of the York 

Haven Project. Operation and management of project lands and waters would continue to 

affect the conditions of these shoreline resources. York Haven Power proposes to 

continue to provide public recreation access and lease recreational lots on the islands of 

the project. We conclude in section 3.3.5.2, Recreation and Land Use Resources,

Environmental Effects, that preparation of an SMP that combines the shoreline permit 

program, York Haven’s proposed monitoring program, development of an enforcement 

program, and provides a classification system to ensure resources are balanced in a 
373

comprehensive manner would be beneficial and ensure that the shoreline development 

pattern is consistent with project purposes, objectives, and any future license 

requirements. Development of a final SMP in consultation with the Pennsylvania FBC, 

Pennsylvania DCNR, and FWS would help to ensure that the management of project 

lands and waters along Lake Frederic’s shorelines is consistent with the latest Guidance 

for Shoreline Management Planning at Hydropower Projects (FERC, 2012). Updating 

the SMP every 10 years would recognize the potential for growth and development along 

the project reservoir over the term of the license. We estimate the levelized annual cost 

to develop and update an SMP every 10 years would be $6,750. The benefit to the 

environmental resources along the shoreline would be worth the cost. 

Debris Removal

York Haven Power proposes, consistent with the Settlement Agreement, to 

continue to remove non-natural debris from the forebay and sluice remaining natural 

debris downstream, with advance notification to PPL BI. As discussed in section 3.3.5.2, 

Recreation and Land Use Resources, Environmental Effects, and section 3.3.7.2,

Aesthetic Resources, Environmental Effects, debris accumulation, removal, and passing 

are part of operating a hydroelectric project. The presence of debris in project reservoirs 

can present safety and aesthetic hazards; however, the dynamic nature of the volume and 

timing of debris within any reservoir at any given time makes managing it dynamic as 

well. The removal and/or passing of debris that has accumulated in front of the 

trashracks are important components of operating hydroelectric projects of any size. 

Given the size of the lower Susquehanna River watershed, the amount of debris arriving 

and passing these projects can be significant. Implementing the debris management as 

detailed in the Settlement Agreement and proposed by York Haven Power would ensure 

debris does not pose long-term hazards to people and project operation. Notification of 

PPL’s Brunner Island steam plant would be a continuation of the courtesy York Haven 

Power provides to allow PPL opportunity to plan or prepare for any inconvenience from 

passing debris. The continuation of debris removal immediately downstream of the York 

Haven Project is a benefit to the project that would not add any additional cost. 

Project Boundary

The East Shore boat launch and Lock 15 provide recreation access and 

opportunities to York Haven Project lands and waters; however, not all of the lands 

associated with these two project recreational features are currently within the project 

boundary. The Commission would not have jurisdiction over areas if they are located 

outside of the project boundary. Commission regulations require that all lands necessary 

for the operation and maintenance of the project and for other purposes, such as 

recreation, be included in the project boundary. Modifying the project boundary to 

include all of the lands associated with the East Shore boat launch and Lock 15 would 

ensure these recreation amenities are provided for the public’s enjoyment for the term of 
374

any license issued for the project. We estimate that the cost of including these sites 

within the project boundary would be minimal, and the benefits would be worth the costs. 

Cultural Resources

York Haven Power proposed to implement the HPMP, filed on 

December 28, 2012, that provides for the management of cultural resources and historic 

properties within the York Haven APE. Our analysis in section 3.3.6.1, Cultural 

Resources, Affected Environment, indicates that, while the HPMP includes many of the 

standard requirements of a historic properties management plan, some measures 

contained within the HPMP would benefit from clarification and/or more detail. In 

addition, there are other measures that would be worth inclusion in the HPMP, and 

inclusion of these measures would ensure that the York Haven Project would not 

adversely affect historic properties over the term of any license. As such, we recommend 

the implementation of York Haven’s proposed HPMP, but with the following additions: 

(a) a requirement to request landowner permission to access sites on private lands within 

the project boundary and evaluate them for listing on the National Register and for 

project impacts if project impacts are identified during monitoring activities; (b) a plan 

and schedule to evaluate archaeological sites on York Haven lands within the project 

boundary for their National Register eligibility to ensure that any effects to sites owned 

by York Haven Power are fully considered in accordance with section 106; and 

(c) inclusion of two additional sites (36YO300, 36YO334) in the monitoring schedule, or 

clarification regarding why they were excluded. We estimate that the levelized annual 

cost to revise and implement the HPMP for the project would be $4,840 and conclude the 

benefits of cultural resource protection justify the cost.

5.1.1.3 Measures Not Recommended

Minimum Flows 

PPL Brunner Island requests that York Haven Power release a continuous 

minimum flow of 1,500 cfs to ensure adequate downstream flows for the full capacity 

operation of the Brunner Island Station. As discussed in section 3.3.2.2, Water 

Resources, Environmental Effects, York Haven Project would operate under run-of-river 

operation during extreme low-flow periods, and would therefore have no ability to 

provide supplemental flows to enable Brunner Island station to operate at full capacity 

under such flow conditions. Further, York Haven Power provides PPL BI with advanced 

notice when debris is going to be manually passed downstream, and York Haven Power 

has no control over the debris once it passes downstream. 

Debris Removal in the Lower Susquehanna River Watershed

York Haven Power proposes to provide $25,000 to an entity identified by 

Pennsylvania DEP to remove debris in the lower Susquehanna River watershed as 

provided for in the Settlement Agreement. As discussed in section 3.3.2.2, Water 
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Resources, Environmental Effects, and section 3.3 5.2, Recreation and Land Use 

Resources, Environmental Effects, almost all of the debris arrives at the York Haven 

project and passes over the main dam during high-flow events when river flows far 

exceed the hydraulic capacity of the project. York Haven removes the non-natural debris 

that accumulates in the forebay, and the remaining debris is sluiced downstream. We 

find that, under these conditions, York Haven has no control over the quantity of debris 

that flows downstream or where it is deposited. This proposed measure appears not to be 

related to any specific project impact at York Haven, nor would the measures necessarily 

be implemented in the project area. With a lack of nexus to the project, and because 

providing funds is inconsistent with Commission’s guidelines on environmental 

measures,90 we do not recommend including this as a license condition. We have no 

objection to York Haven providing these funds; however, we do not include this measure 

in our staff alternative. 

5.1.2 Muddy Run Project

5.1.2.1 Measures Proposed by Exelon

Based on our environmental analysis of Exelon’s proposal in section 3, 

Environmental Effects, and the costs presented in section 4, Developmental Analysis, we 

conclude that the following environmental measures proposed by Exelon would protect 

and enhance environmental resources and would be worth the cost. Therefore, we 

recommend including these measures in any license issued for the project. We discuss 

any modification to Exelon’s proposed measures below under Measures Recommended 

by Staff for the Muddy Run Project.

• Develop a DO monitoring plan no earlier than November 1, 2027, with 

measures designed to ensure that the project does not violate DO standards.

• Develop FPOP for minimizing delay and potential fish entrainment during 

upstream and downstream fish passage past the project tailrace during 

generating and pumping cycles. 

• Develop a plan and schedule for a radio telemetry study or equivalent Tier 

II study of American shad passage and behavior within the Muddy Run 

Project boundary if resource agencies determine that operation of the 

Muddy Run Project is causing the Holtwood Project to fail to meet the 

Tier I upstream American shad target specified in the water quality 

certification for the Holtwood Project.

 

90 See Policy Statement on Hydropower Licensing Settlements, issued 

September 21, 2006.
376

• Implement the Bald Eagle Management Plan filed with the license

application to minimize impacts to bald eagles and their habitat within the 

project boundary in accordance with recommendations from the National 

Bald Eagle Management Guidelines (FWS, 2007a) and state agency 

guidance. 

• Implement the Bog Turtle Management Plan filed with the license 

application to minimize impacts to bog turtles and that includes: (1) the 

restriction of mowing in the wetland documented to support bog turtles; 

(2) invasive and woody plant control, particularly for reed canary grass; and 

(3) limits on public access to the wetland without advertising the reason.

• Implement the Recreation Management Plan filed with the license 

application that includes the following improvements to project recreation 

facilities: an improved launching ramp and ADA-compliant dock; 

shoreline erosion measures; an improved retaining wall; electric upgrades; 

expanded playground area near the Visitor’s Center; and construction of a 

2,000-square-foot water spray park near the park entrance, along with 

paving resurfacing (see section 2.2, Applicants’ Proposals, for a full 

description of proposed capital improvements at each site). 

• Implement the SMP filed with the license application that includes 

measures and policies related to shoreline vegetation management and 

erosion control, woody debris management, game species management, 

sensitive natural resource protection, recreation use, and use of project 

lands and BMPs for controlling sediment introduction. 

• Implement the osprey management policy described in Exelon’s proposed 

SMP.

5.1.2.2 Additional Measures Recommended by Staff for Muddy Run

We recommend Exelon’s proposed measures as described above with the 

following additions or modifications: 

• Visit FWS’ Chesapeake Bay Field Office and the Pennsylvania Field Office 

websites prior to any ground disturbance, and follow the bog turtle and bald 

eagle guidelines. 

• Modify Exelon’s proposed Recreation Management Plan to include 

recreation use monitoring and plan updates every 12 years in concert with

every other Form 80 reporting deadline.

• Modify Exelon’s proposed SMP to include a provision to update the plan 

every 10 years. 

• Develop an HPMP that provides for the management of historic properties 

and unevaluated cultural resources within the project APE and includes: 
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(a) a detailed discussion of the three sites (36LA67, 36LA103, 36LA368)

identified during the Phase IA cultural resources survey and the two 

additional sites (36LA70, 36LA47) located outside of the project boundary

but located within the APE; (b) requirements for National Register 

evaluation of affected sites in consultation with the Pennsylvania SHPO; 

(c) requirements for formal National Register evaluation of the Muddy Run 

Project; and (d) documentation of consultation with Indian tribes. 

Below we discuss the rationale for recommending proposed measures, modified 

measures, and additional staff measures for the Muddy Run Project. 

DO Monitoring

Exelon proposes, consistent with the Pennsylvania DEP certification, to develop a 

DO monitoring plan no earlier than November 1, 2027, with measures designed to ensure 

that the project does not violate DO standards. While water quality monitoring at the 

project found that violations of state water quality standards are rare, implementing this 

plan would ensure that standards are maintained. We did not estimate a cost for 

developing and implementing a DO monitoring plan because it would be more than 

10 years before the plan would be developed, and any estimated costs developed now 

may not be relevant in the future. 

Fish Passage

Exelon proposes, consistent with the Pennsylvania DEP certification, to develop

and implement an FPOP for upstream and downstream fish passage, and to develop and 

implement a plan and schedule for a radio telemetry study or equivalent Tier II study of 

American shad passage and behavior within the Muddy Run Project boundary if resource 

agencies determine that operation of the Muddy Run Project is causing the Holtwood 

Project to fail to meet its Tier I upstream American shad target prescribed in the 

certification for the Holtwood Project. As we describe in our discussion of upstream fish 

passage in section 3.3.2.2, Water Resources, Environmental Effects, the Muddy Run 

Project is not a blockage to upstream migration, but may affect migrating fish by causing 

flow patterns that may confuse or delay fish passing the project, or may entrain fish 

during the pumping cycle. While such effects may occur, information to date indicates 

that the project has not had a substantial effect on upstream and downstream shad 

movement past the project. Nonetheless, Exelon proposes to monitor future passage by 

the project by use of the FPOP and a possible Tier II study, if the Holtwood Project does 
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not meet its Tier I target.91 These measures would provide a mechanism for determining 

whether passage objectives are met, and if not, would allow application of potential 

corrective measures. We estimate that implementation of an FPOP would not require 

additional costs above current operation and maintenance costs, while a future Tier II 

study is speculative and may or may not occur in the future.

Downstream Eel Passage Plan

Exelon proposes, consistent with the Pennsylvania DEP certification, to 

implement a downstream eel passage plan to ensure safe and effective downstream eel 

passage past the project. Exelon would maintain downstream eel passage efficiency rates 

of at least 85 percent through the Muddy Run Project area. However, our recommended

compliance date when that would be required is October 1, 2026, consistent with the 

certification, once sufficient numbers of eels have been released into the Susquehanna 

River to produce a substantial number of downstream-migrating silver eels. Exelon 

would be required to conduct studies to demonstrate compliance with the passage rate, 

and if not achieved would be required to provide mitigation. We have not included an 

estimated cost for this measure because it would occur more than 10 years into the future, 

and any mitigation would be speculative and dependent on whether or not the target 

passage rates would be met.

Bald Eagle Management Plan

Exelon proposes to implement the Bald Eagle Management Plan filed with the 

license application that provides for the management of bald eagle habitat on Exelon 

lands at the Muddy Run Project based on recommendations from the FWS National Bald 

Eagle Management Guidelines and state agency guidance. This includes implementing 

distance and landscape buffers around nesting sites and avoiding certain activities during 

nesting season. In addition, the Bald Eagle Management Plan includes guidelines for 

activities around roosting and foraging areas. The plan also includes provisions for 

monitoring of nesting, roosting, and foraging sites every 5 years and injury and mortality 

reporting procedures. Interior also recommends, as a 10(j) measure, the development a 

bald eagle management plan based on the FWS National Bald Eagle Management 

Guidelines and state agency guidance. Our analysis in section 3.3.3.2, Terrestrial 

Resources, Environmental Effects, provides our rationale for recommending the

implementation of the Bald Eagle Management Plan, as proposed by Exelon and 

recommended by Interior, because it would benefit bald eagles within the Muddy Run 

 

91 The Tier 1 target is that 75 percent of the fish passing the downstream 

Conowingo Project are passed at Holtwood. If that target is not met, then the Tier II 

requirement is that 85 percent of the fish that arrive in the Holtwood Project area must be 

passed upstream of Holtwood, and the only methodology currently available to make that 

determination is radio telemetry.
379

Project boundary by complying with bald eagle management guidelines and state 

guidelines, ensuring that future bald eagle nest, roost, and foraging areas are also 

protected by the Bald Eagle Management Plan, and ensuring that FWS and Pennsylvania 

Game Commission are aware of any project-related bald eagle mortality for the term of 

any new license. We estimate that the levelized annual cost of implementing the Bald 

Eagle Management Plan would be $750 and conclude the benefits of protecting bald 

eagles justify this minimal cost.

Osprey Management Policy

Exelon proposes to implement the osprey management policy described in the 

SMP filed with the license application that states Exelon would work with state and 

federal agencies to provide appropriate buffers dictated by the types of activities carried 

out in either visual or auditory proximity to nests during breeding and nesting season 

(January to late July). This includes implementation of: (1) nest buffers during the 

breeding season of 330 feet for most activities and larger buffers up to 600 feet for 

activities with the potential to emit excessive noise (which excludes routine project 

operation and maintenance activities), and (2) restriction on herbicide application within 

330 feet of osprey nests during breeding season. Under the policy, Exelon would consult 

with FWS and Pennsylvania Game Commission to determine BMPs and obtain 

applicable permits in the event an osprey nest on project transmission line towers is 

identified as a problem nest that needs to be removed or relocated. We recommend 

adoption of Exelon’s proposed osprey management policy. Our analysis in section 

3.3.3.2, Terrestrial Resources, Environmental Effects, indicates implementation of the 

osprey management policy would benefit the osprey by enacting protection measures and 

following BMPs. The costs associated with implementation of the osprey management 

policy are included in the cost estimate for implementing the SMP. 

Bog Turtle Management Plan

Exelon proposes to implement the Bog Turtle Management Plan filed with the 

license application, which is consistent with Interior’s recommended measure to develop 

and implement, in consultation with FWS and Pennsylvania FBC, a bog turtle 

management plan for the Muddy Run Project. Exelon’s proposed Bog Turtle 

Management Plan includes: (1) a restriction of mowing in the wetland documented to 

support bog turtles; (2) invasive plant and woody plant control, particularly for reed 

canary grass; and (3) possible limits on public access to the wetland without advertising 

the reason. We provide our rationale for recommending the Bog Turtle Management 

Plan in section 3.3.4.2, Threatened and Endangered Species, Environmental Effects.

This section indicates the Bog Turtle Management Plan would ensure that invasive 

species are controlled in the area and the wetland is not affected by vegetation 

management during the emergence and breeding season. We estimate that the levelized 

annual cost of the Bog Turtle Management Plan would be $8,240 and conclude the 

benefits of protecting the federally listed bog turtle justify the cost.
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Recreation Management Plan

Exelon proposes to implement the Recreation Management Plan filed with the 

license application that also includes a schedule for implementing proposed recreational 

enhancements at the Muddy Run Project. A recreation plan would allow Exelon to 

implement facility improvements and install new facilities in a coordinated manner, and 

would ensure that the proposed recreational facility improvements meet the intended 

purposes. However, the plan does not include a specific provision for reviewing and 

updating the plan over the term of any license issued. The staff alternative would include 

revising the plan to specify visitation and sedimentation monitoring of the boat ramp to 

maintain boater access and consultation efforts as part of the plan. We recommend that 

the Recreation Management Plan include measures to conduct a recreation use study 

every 12 years, consistent with every other FERC Form 80 reporting deadline, as well as 

review and consultation with resource agencies, counties, and other interested 

stakeholders in the project area, such as Pennsylvania FBC, Pennsylvania DCNR, 

Maryland DOE, and Maryland DNR. We estimate the levelized annual cost of the 

revised plan would be $2,370. We conclude that these costs would be worth the 

substantial benefits that would be derived from implementing the revised plan. 

Recreation Facility Improvements

As part of the Recreation Management Plan, Exelon proposes to upgrade a variety 

of amenities within Muddy Run Park and make repairs at Wissler’s Run Park near the 

Muddy Run powerhouse. As part of the improvements, Exelon would replace the 

existing boat launch facility at Recreation Lake with a new concrete plank ramp, a new 

gangway, and floating dock (ADA compliant), and also make shoreline improvements to 

limit erosion. Exelon also proposes to upgrade the ADA-compliant picnic site, stabilize 

150 feet of the shoreline at Recreation Lake between the ADA-compliant picnic site and 

the rental boat dock, convert the timber retaining wall to sheetpile retaining wall, upgrade 

service to 50-amp electrical service at 50 sites, expand the playground adding a “tot lot,” 

construct a spray park, and provide Wi-Fi service to park users. Proposed improvements 

to Wissler's Run Park would include removing the non-functioning fish cleaning station, 

rebuilding and repaving the existing walkway along the top of the bank, and designating 

two parking spaces near the picnicking pavilion as meeting ADA standards. As part of 

the plan, Exelon also proposes to erect and maintain FERC Part 8 signs at River Road 

and Furniss Road Muddy Run WMA parking areas. Exelon proposes to continue to lease 

these lands to the Pennsylvania Game Commission for the term of a future license. In 

our analysis in section 3.3.5.2, Recreation and Land Use Resources, Environmental 

Effects, we conclude that improvements to the Recreation Lake boat ramp, ADAcompliant picnic area, shoreline, and retaining walls would improve boater access and 

maintain water quality by reducing runoff from these areas. Further, improvements to the 

ramp would enhance boater access; a popular activity on the lake. Similarly, 

improvements to the campground electrical service that include more 50-amp service 

campgrounds and Wi-Fi would address modern camper needs such as increased use of 
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electronic devices (e.g., recreational vehicles with air conditioning, personal computers, 

and smart phone charging). Removal of the non-functioning fish cleaning station at 

Wissler’s Park would eliminate the temptation for users to clean fish on site and leave the 

waste, which could negatively affect the aesthetics of the area. Enhancements to the 

pathway and designating two additional parking areas as ADA-compliant would improve 

the overall recreation experience. For these reasons, we recommend implementation of 

Exelon’s proposed recreation facility improvements. The estimated levelized annual cost 

of these capital improvements would be $197,320. The benefit of upgrading and 

expanding recreational opportunities at the project recreation sites is worth the cost. 

Shoreline Management Plan

Exelon proposes to implement the SMP filed with the license application that 

includes specific measures and policies related to shoreline vegetation management and 

erosion control, woody debris management, game species management, sensitive natural 

resource protection, recreation use, and use of project lands and BMPs for controlling 

sediment loading from lands within the project boundary. In our analysis in 

section 3.3.5.2, Recreation and Land Use Resources, Environmental Effects, we conclude 

that implementation of the SMP would provide policies to manage the project’s 

shorelines and protect the environmental resources, including bald eagle and osprey 

habitat and aesthetics along the Muddy Run Project’s upper reservoir and would help to 

minimize effects from erosion on the reservoir’s shoreline. Revising the SMP to include 

regular updates every 10 years in consultation with interested stakeholders consistent 

with the latest Guidance for Shoreline Management Planning at Hydropower Projects 

(FERC, 2012) would ensure the plan is harmonious with conditions at the project. We 

conclude that the addition of regular updates and consultation to the SMP would be worth 

the estimated levelized annual cost of $1,440 to revise the SMP.

Historic Properties Management Plan 

Exelon proposes to develop a cultural resources management plan if cultural 

materials are identified during project-related activities. Interior, under section 10(a),

recommends that Exelon develop and implement an HPMP that provides for the 

management of historic properties and unevaluated cultural resources within the project 

APE. The HPMP would be prepared in accordance with the Advisory Council and 

Commission’s joint guidance document for preparing hydroelectric project HPMPs 

(FERC and Advisory Council, 2002) and would include: (a) a detailed discussion of the 

three sites (36LA67, 36LA103, 36LA368) identified during the Phase IA cultural 

resources survey and two additional sites (36LA70, 36LA47) located outside of the 

project boundary but within the project’s APE; (b) requirements for National Register 

evaluation of affected sites in consultation with the Pennsylvania SHPO; and 

(c) requirements for formal National Register evaluation of the Muddy Run Project 

facility; and (d) documentation of consultation with Indian tribes. Our analysis in section 

3.3.6.2, Cultural Resources, Environmental Effects, concludes that implementation of this 
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measure would ensure that the Muddy Run Project would not adversely affect historic 

properties during the term of any license. We estimate that the levelized annual cost of 

development and implementation of an HPMP for the project would be $31,150 and 

conclude the benefits of protecting cultural resources and historic properties justify the 

cost.

5.1.2.3 Measures Not Recommended

Eel Passage Plan

The certification requires implementation of Exelon’s American Eel Passage Plan, 

in which Exelon would establish an Eel Passage Advisory Group to help implement the 

plan, and would trap, hold, and transport American eels from Conowingo dam to 

designated points in the Susquehanna River watershed. Exelon has agreed to this 

measure in the certification for the Muddy Run Project, and would also implement this 

plan as a measure for the Conowingo Project. While we are recommending these 

measures at Conowingo (see section 5.1.3.1, Conowingo Project – Measures Proposed 

by Exelon), we do not recommend those measures as requirements of any license for the 

Muddy Run Project because the Commission cannot require a condition in any Muddy 

Run license that would need to be implemented at another licensed project.

Grants to Conservation Districts

Consistent with the water quality certification, Exelon proposes to provide 

$450,000 to be split equally between the York County and Lancaster County 

conservation districts for the implementation of agricultural pasture and barnyard BMPs 

to control sediment introduction into the Susquehanna River. Exelon would provide 

another $50,000 to the Pennsylvania FBC to perform habitat improvements, including the 

removal of small dams. 

The compensatory mitigation requirement of the certification does not specify nor 

describe what the compensation is mitigating. Funds would be used for BMPs to reduce 

sediment loading to the river and for habitat improvement, including dam removal. This 

requirement appears not to be related to any specific project impact, nor would the 

measures necessarily be implemented in the project area. With a lack of nexus to the 

project, and because providing funds is inconsistent with Commission’s guidelines on 

environmental measures,92 we do not recommend it be included as a license condition. 

While we have no objection to Exelon providing these funds, we do not include this 

measure in our staff alternative. We recognize, however, that these measures are

 

92 See Policy Statement on Hydropower Licensing Settlements, issued 

September 21, 2006.
383

included in the certification for the Muddy Run Project, so they would be a mandatory 

condition of any license issued for the project. 

Rare, Threatened, and Endangered Species Annual Evaluation

Exelon proposes a plan to evaluate all state and federal endangered or threatened 

species that may be present within the project boundary once every 10 years through the 

term of the license. If the evaluation identifies the presence, critical habitat, or critical 

dependence of endangered species, Exelon would propose and, following approval, 

implement a plan to ensure protection of endangered or threatened species. Our analysis 

in section 3.3.3.2, Terrestrial Resources, Environmental Effects, indicates that although 

we agree that this measure would allow Exelon to continue to be aware of the current 

rare, threatened, and endangered species populations in the Muddy Run Project during 

the length of any license, the Commission typically includes in its licenses a standard 

license article with a fish and wildlife reopener provision that could be used to require 

changes to project facilities upon Commission motion or as recommended by the 

appropriate federal and state fish and wildlife agencies after notice and opportunity for 

hearing. This standard reopener provision retains authority for the Commission to 

implement any measures that may be needed to protect threatened or endangered species 

or other fish and wildlife resources over the term of any license issued for the project. 

Although we have no objection to Exelon conducting this agency consultation, we feel 

that the standard license article would provide a similar level of protection as the 

proposed measure. We recognize, however, that this measure is included in the 

certification for the Muddy Run Project, so it would be a mandatory condition of any 

license issued for the project.

5.1.3 Conowingo Project

5.1.3.1 Measures Proposed by Exelon

Based on our environmental analysis of Exelon’s proposal in section 3, 

Environmental Effects, and the costs presented in section 4, Developmental Analysis, we 

conclude that the following environmental measures proposed by Exelon would protect 

and enhance environmental resources and would be worth the cost. Therefore, we 

recommend including these measures in any license issued for the project. We discuss 

any modification to Exelon’s proposed measures under Measures Recommended by Staff 

for the Conowingo Project.

• Operate the project with a normal range of operation of Conowingo Pond 

between elevations 101.2 and 110.2 feet, with a minimum elevation of 

107.2 feet on weekends between Memorial Day and Labor Day, to meet 

recreational needs.

• Enhance DO at the project using the turbine venting systems on Units 1 

through 7 and the aerating runners on Units 2 and 5, and continuously 
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monitor DO levels from May 1 through October 1 at the Station 643 

location about 0.6 mile downstream of Conowingo dam.

• Operate the east fish lift to pass American shad, river herring, and other 

migratory fishes, and the west fish lift for American shad egg collections 

and other research purposes.

• Manage debris to include clamming (with three gantry cranes with grapple 

attachments) to remove submerged debris from the area upstream of the 

powerhouse intakes and floating surficial debris in front of the powerhouse 

intakes, and sponsoring community-based clean-ups in the pond and 

downstream of the dam.

• Implement the Sediment Management Plan filed with the license 

application that identifies benchmarks and thresholds for action to address 

sediment issues that may affect project operation. 

• Conduct a bathymetric survey of Conowingo Pond every 5 years to monitor 

sediment transport and depositional patterns within the pond.

• Implement a preventive maintenance program for the east fish lift to extend 

the useful life of the facility over the next license term.

• Use the project turbines as the route for downstream passage of American 

shad and river herring.

• Construct a permanent trap and transport facility for upstream passage of 

American eel, consisting of an eel ramp and collection facility on the west 

and east banks of the Conowingo tailrace (an alternative east bank facility 

would be in Octoraro Creek).

• After 2030, construct volitional eel passage facilities on the west and east 

banks that consist of full eel ramps with resting pools. 

• Participate in a trap and transport program for downstream eel passage, in 

cooperation with the other hydroelectric project operators on the lower 

Susquehanna River to trap and transport adult American eels from smaller 

tributaries upstream of York Haven dam to below Conowingo dam.

• Implement the Bald Eagle Management Plan filed with the license 

application to minimize impacts to bald eagles and their habitat within the 

project boundary in accordance with recommendations from the National 

Bald Eagle Management Guidelines (FWS, 2007a) and state agency 

guidance. 

• Implement the Recreation Management Plan filed with the license 

application that provides for improvements to 13 project recreation 

facilities, including directional signage to facilities and canoe portages, 

expanded parking, ADA-compliant and boat trailer parking spaces, fencing, 
385

shoreline stabilization, new or repaired boat ramps, improved access, picnic 

tables, portable restrooms, and other amenities. 

• Implement the SMP filed with the license application that includes

measures and policies related to shoreline vegetation management and 

erosion control, woody debris management, game species management, 

sensitive natural resource protection, recreation use, BMPs for controlling 

sediment introduction from lands within the project boundary, and use of 

project lands. 

• Implement the osprey management policy described in Exelon’s SMP. 

• Implement the HPMP filed with the license application for the management 

of archaeological and historic resources, including: (1) a schedule and 

methodology for completing any additional recommended studies and 

implementing monitoring measures; (2) management measures for 

identified historic properties including Conowingo dam and powerhouse; 

(3) protection of any historic properties threatened by project-related 

activities, including project operation, shoreline and aquatic recreation, 

shoreline development, routine project maintenance, and other project 

activities or operations; and (4) public outreach, education, and signage for 

the purpose of reducing looting and vandalism of sites.

5.1.3.2 Additional Measures Recommended by Staff for Conowingo

We recommend Exelon’s proposed measures as described above, with the 

following additions and modifications: 

• Modify Exelon’s proposed Sediment Management Plan to include periodic 

dredging at the Conowingo Creek, Peters Creek (Peach Bottom Marina), 

and Broad Creek boat ramps, where sediments have been accumulating, to 

improve and maintain recreational boating access; and include with the 

results of each bathymetric survey an analysis of any change in sediment 

deposition or scour in the pond from the previous survey(s). 

• Modify Exelon’s proposed minimum flow regime to enhance minimum 

flows from December through February, by eliminating periods with no 

minimum flow, and by increasing the minimum flow during the first 2 

weeks of June, summarized as follows: 

− September 15 – March 31: 3,500 cfs or natural inflow (as measured at 

the USGS Marietta gage No. 0157600), whichever is less;

− April 1 – April 30: 10,000 cfs or natural inflow, whichever is less;

− May 1 – June 15: 7,500 cfs or natural flow, whichever is less;

− June 16 – September 14: 5,000 cfs or natural inflow, whichever is less. 
386

• Implement measures designed to improve upstream fish passage through 

modification to the existing west and east fish lifts, including: (a) replacing 

the existing hopper at the west fish lift with a 1,500 gallon hopper; 

(b) improving the west fish lift sorting and loading process to facilitate trap 

and truck operations and implement a trap and truck program for American 

shad; (c) conducting a feasibility study for adding attraction flow at the 

west fish lift and if feasible and beneficial, install additional flow capacity; 

(d) restoring the original design for the 900-cfs attraction flow in the east 

fish lift; (e) adding a second 3,300-gallon hopper to the east fish lift in the 

space provided for in the original design, and upgrading the electrical and 

mechanical equipment to allow for a 15 minute lift cycle; and (f) if 2 years 

of effectiveness studies, after restoration of the 900-cfs attraction flow, 

show poor attraction at the east fish lift, conducting a feasibility study for 

modifying the locations of entrances A and B, and implement if feasible. 

• Modify Exelon’s proposed Bald Eagle Management Plan to include 

measures to minimize recreation-related disturbance in proximity to 

roosting or foraging eagles.

• Develop a northern map turtle protection plan to minimize project impacts 

to map turtles through monitoring, habitat management, and nest 

site protection. 

• Develop a waterfowl nesting protection plan to identify waterfowl nesting 

habitat that is routinely flooded during the breeding season, and where 

feasible, establish mitigation measures to minimize impacts to 

waterfowl nests. 

• Modify Exelon’s proposed Recreation Management Plan to include 

recreation use monitoring and plan updates every 12 years in concert with 

every other the Form 80 reporting deadline and a plan to provide angler 

access to the catwalk on a limited basis and security measures in place that 

address the vulnerability of the facility and the safety of the users of 

the catwalk.

• Modify Exelon’s proposed SMP with the addition of a provision to update

the plan every 10 years.

• Modify Exelon’s proposed HPMP to include the following additional 

provisions: (a) a revised APE with the narrow strip of land in the current 

project boundary extending downstream from Spencer Island along the 

west side of the river to Havre de Grace, Maryland; (b) a discussion of all 

48 sites and 27 historic structures identified to date within the project APE 

or an explanation of why they are not considered; (c) correction to identify 

the Susquehanna and Tidewater Canal and Columbia & Port Deposit 

Railroad eligible for listing; (d) requirements to inventory any lands within 
387

the revised APE, evaluate identified cultural resources for eligibility, and 

address potential effects before sale or transfer of those lands; (e) a 

requirement to make a good faith effort to obtain access to private property 

to conduct studies if project effects on cultural resources on private lands 

are identified; (f) a revised list of project activities involving the 

Conowingo Project that can be completed without Maryland SHPO review; 

(g) a process for assessing project-related ground-disturbing activities to 

determine whether or not archaeological sites would be affected, 

particularly in areas that have not had archaeological surveys; 

(h) requirements to ensure confidentiality of cultural resources location 

information during implementation of public outreach programs; and (i) a 

description of project-related activities that would require consultation with 

the Delaware Nation and the Onondaga Nation in accordance with section 

106 of the NHPA and documentation of Native American consultation. 

Below we discuss the rationale for recommending proposed measures, modified 

measures, and additional staff measures for the Conowingo Project. 

Reservoir Operations

Exelon is proposing to continue operating Conowingo Pond using the same 

reservoir operating limits as currently employed. Currently, Exelon operates Conowingo 

Pond between elevations 101.2 and 110.2 feet, with a minimum elevation of 107.2 feet on 

weekends between Memorial Day and Labor Day, to meet recreational needs. No entity 

made recommendations to change the current reservoir elevations, and our analysis found 

that current reservoir operation adequately protect aquatic resources and recreational use 

of the reservoir. Therefore, we are recommending continuation of existing reservoir 

operation, which can be implemented at no additional cost to the project. 

DO Enhancement Measures

Exelon is proposing to continue DO enhancement at the project using turbine 

venting and aeration. Since placed into operation, these systems have been shown to 

maintain adequate DO levels downstream of the project nearly 100 percent of the time. 

Exelon would also continuously monitor DO levels from May 1 through October 1 at the 

Station 643 location about 0.6 mile downstream of Conowingo dam. No entities have 

recommended additional measures for protection or enhancement of DO levels, and 

because state standards are being met, we are recommending continuation of existing DO 

measures and DO monitoring. These measures and monitoring can be implemented at no 

additional cost to the project. 

Sediment Management and Bathymetric Surveys

Exelon proposes to implement the Sediment Management Plan filed with the 

license application to identify benchmarks and thresholds for actions to address sediment 
388

issues that may affect project operation. Exelon also proposes to conduct bathymetric 

surveys every 5 years. In section 3.3.1.2, Geology and Soils, Environmental Effects, we 

conclude that these measures are relevant tools for managing the sediment accumulation 

issues in the reservoir, ensuring effective power generation, maintaining recreation

facilities, as well as providing information for environmental management of the lower 

Susquehanna River system and Chesapeake Bay. Implementation of the proposed 

Sediment Management Plan would include monitoring of the water depth at Peter’s 

Creek (Peach Bottom Marina), Conowingo Creek, and Broad Creek (Harford County 

boat launch) every 5 years; however, the plan stops short of identifying at what depths the 

locations need to be dredged and scheduling dredging. These three boat ramps represent 

half of the boat ramps providing access to Conowingo Pond for motorized boating. As 

discussed in our analysis in section 3.3.5.2, Recreation and Land Use Resources,

Environmental Effects, cross referencing the bathymetric mapping proposed under the 

Sediment Management Plan at the three sites into the final Conowingo Recreation 

Management Plan would ensure bathymetric mapping results are included in discussions 

related to boater access to the reservoir. Development of a final Sediment Management 

Plan that includes detailed benchmarks for dredging, a schedule, and commitment to 

dredging the three access areas as soon as the benchmark water depths are reached would 

ensure that recreation access is not lost or compromised indefinitely. We estimate that 

the levelized annual cost of implementing regular bathymetric surveys at 5-year intervals

and implementing the Sediment Management Plan would be $10,480 and $6,220, 

respectively. We estimate the levelized annual cost of dredging at the three boat ramps 

would be $493,030. We conclude that the benefits of understanding and managing 

sedimentation issues in the reservoir and ensuring accessing to the reservoir justify the 

cost of these measures. We note, however, that relevant findings in the Corps’ LSRWA 

study report, if available in time, may result in additional recommendations in the final 

EIS or in any license order issued for the project, depending on when the study results are 

available to Commission staff. 

Instream Flows

Exelon proposes to continue its current minimum flow releases from the project, 

which are an alternating 0/3,500 cfs (6 hours on/6 hours off) from December through 

February, 3,500 cfs in March, 10,000 cfs in April, 7,500 cfs in May, 5,000 cfs from June 

through September 14, and 3,500 cfs from September 15 through November.93 Exelon is 

not proposing any changes in the current maximum generating flow rate from the project 

(86,000 cfs), or in project ramping rates. Interior, in its section 10(j) recommendation, 

stated that Exelon should finalize and implement a flow management plan and implement 

the flow recommendations of The Nature Conservancy or any more restrictive flows 

 

93 Exelon would provide the lesser of these flows or the natural inflow at the 

upstream Marietta, Pennsylvania USGS gage No. 0157600.
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required by the Maryland certification (when issued), returning the river downstream of 

Conowingo to more natural conditions. The Nature Conservancy recommended flows be 

released downstream of Conowingo dam sufficient to achieve several habitat objectives 

for diadromous and resident fish species, mussels, map turtles, and submerged aquatic 

and emergent vegetation (the TNC Flow Regime). The Nature Conservancy also 

recommended that the EIS evaluate two operational alternatives: (1) run-of-river 

operation (passage of the daily average flow measured at the USGS Marietta, 

Pennsylvania, gage plus any intervening flows that enter the river between the Marietta 

gage and Conowingo dam); and (2) the set of operational constraints that The Nature 

Conservancy identified as a potential approach for meeting its performance goals.

Our analysis found that, overall, the current and proposed Exelon operations 

generally bracket the range of flows that would provide 70 percent of MWUA (a primary 

goal of the TNC Flow Regime) for target species, as determined by Exelon’s instream 

flow study. However, we also found that some small adjustments to Exelon’s proposed 

flow regime would provide additional benefits to aquatic habitat. These adjustments 

include: (1) eliminating the 6-hour periods of zero minimum flow from December 

through February, resulting in a continuous minimum flow of 3,500 cfs from September 

15 through March; and (2) increasing the minimum flow from 5,000 to 7,500 cfs during 

the first 2 weeks in June, to protect the end of the spawning period for shad and 

striped bass. 

While we conclude that the flow issue downstream of Conowingo dam is 

complex, our analysis found that Exelon’s current flow regime is generally adequate for 

protection of aquatic resources downstream of the project, although the adjustments to 

these flows as we discussed would provide additional protection to aquatic habitat. 

Therefore, we recommend that Exelon provide, upon issuance of any new license, a 

modified minimum flow regime downstream of the project as follows:

• September 15 – March 31: 3,500 cfs or natural inflow (as measured at the 

USGS Marietta gage No. 0157600), whichever is less;

• April 1 – April 30: 10,000 cfs or natural inflow, whichever is less;

• May 1 – June 15: 7,500 cfs or natural flow, whichever is less;

• June 16 – September 14: 5,000 cfs or natural inflow, whichever is less.

This modified flow regime would provide the environmental benefits described 

above and would result in a small energy gain at Conowingo (annualized value of 

$2,650), but a small loss in energy (annualized value of $19,190) at Muddy Run. This, 

however, would be worth the cost in providing additional protection to aquatic resources, 

and it would preserve the developmental benefits of the project, including peaking 

generation and ancillary services. 
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Upstream Fish Passage

The Conowingo Project currently operates two fish lifts at the project: the west 

fish lift first constructed in 1972, and now operated primarily for shad egg taking and 

experimental purposes, and the east fish lift constructed in 1991, which provides 

upstream volitional passage for American shad and other species. Exelon proposes to 

continue operating these facilities and to implement a preventive maintenance program at 

the east fish lift to extend the life of the facility through the new license term. Several 

commenting entities have stated that the current facilities are inadequate and outdated and 

fail to meet the current resource agency effectiveness targets to achieve successful 

anadromous fish restoration in the Susquehanna River. Both Interior and NMFS reserve 

their authority to prescribe additional fishways during the term of the license, and Interior

also provides a preliminary fishway prescription for the project for both anadromous and 

catadromous species. Interior also recommends that Exelon prepare an operations and

maintenance plan for Conowingo fish passage facilities, and an FEMP, and as a section 

10(j) measure recommends that alternative G of the preliminary fishway prescription be 

implemented. Alternative G includes: (1) construction of a new west fish lift with two 

lifts for both trap and trucking and direct volitional upstream shad passage; 

(2) modification of the east fish lift stilling basin to allow 900-cfs attraction flow, as 

originally designed, relocation and reconstruction of entrances A and B, and construction 

of a new entrance D and collection gallery; and (3) adjustment of minimum flows and 

turbine operations, construction of an east fish lift auxiliary water supply of 4,325 cfs, 

and upgrades to the east fish lift equipment to allow a 15-minute cycle time if FWS fish 

passage efficiency targets are not met after implementation of the above measures.

Exelon, in its reply comments, states that there is currently no need to construct 

additional fish passage facilities at Conowingo dam, that the recent shad population 

trends in the Susquehanna River and along the Atlantic coast do not indicate that large 

increases in shad populations are likely, and that there is no scientific basis for the target 

effectiveness rates that Interior and other agencies have recommended for fish passage 

facilities at Conowingo and the other Susquehanna River hydroelectric projects. Exelon 

also comments that past agency management decisions for the Susquehanna River have 

been flawed, including the decision to terminate shad trap and truck operations from 

Conowingo after 1996, resulting in a decrease in the number of spawners reaching 

upriver spawning habitat.

As part of our analysis, we assessed fish passage effectiveness for shad at 

Conowingo, other Susquehanna River projects, and other hydroelectric projects in North 

America. We also assessed shad population trends on the Susquehanna River and 

elsewhere on the Atlantic coast, and analyzed the fish passage designs prescribed by 

Interior, compared to alternative designs. Our analysis could not find any scientific basis 

for the agencies’ effectiveness goals; however, those goals are specified in the Migratory 
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Fish Management and Restoration Plan for the Susquehanna River Basin

(SRAFRC, 2010).94 We also could not find any examples where shad upstream passage 

effectiveness has consistently reached such high levels. Safe Harbor Project has the 

highest effectiveness on the Susquehanna River, averaging 71 percent of the fish passed 

at the downstream Holtwood Project, but in many years does not reach that effectiveness. 

On the Columbia River, which has an established large shad population on a multiple 

dam system, passage effectiveness is typically only about 50 to 55 percent of the next 

lower dam. The effectiveness goals of Interior and other agencies may not be realistic or 

achievable. Our review of the shad population in the Susquehanna River found that the 

river exhibited strong population growth from the 1970s into the early 2000s, as a result 

of restoration efforts, but has been in decline since 2001. Exelon and the agencies both 

comment that one of the major reasons for that decline was the suspension of shad 

trapping and trucking in 2000, and the switch to volitional passage in that year. We agree 

and found that the number of shad reaching prime upstream spawning habitat has 

declined significantly since trucking was eliminated. We also discuss other potential 

reasons for the decline in the population, including the very large increase in the gizzard 

shad population in the river since 2000, the introduction of predator species such as the 

flathead catfish, and the continuation of an offshore fishery for shad. The Susquehanna 

River shad population trends also mirror the trends in many other rivers in the 

Chesapeake Bay and along the Atlantic coast, which has been acknowledged by ASMFC. 

Even though the agency fishway effectiveness goals may be overly optimistic and 

that shad populations are depressed coast-wide, we reviewed the fish passage designs at 

Conowingo in light of the Interior preliminary fishway prescription, and because fish 

passage effectiveness at Conowingo has been shown to be low in some years. Our 

assessment of Interior’s preliminary fishway prescription is that the designs it would 

require are overly ambitious and would require a major investment by Exelon in facilities 

that are not needed at present. We agree, however, with Interior and other commenters 

that improvements are needed at the fish lifts, because of maintenance requirements, the 

fact that these facilities are “showing their age,” and that for the east fish lift, it has not 

been operating as it was originally designed. As such, we recommend a phased approach 

to these improvements. The following summarizes the improvements that we 

recommend: (1) replace the existing west lift hopper with a 1,500-gallon hopper, and 

associated structural, electrical, and mechanical upgrades; (2) improve the west lift fish 

sorting and loading process, to facilitate trap and trucking, and purchase trucks, transport 

tanks and associated equipment and implement trap and trucking at the west lift; 

(3) conduct a feasibility study on increasing the west lift attraction flow, and install 

 

94 The agency effectiveness goals are: that 75 percent of the fish passed at a lower 

dam must be passed at the next upstream dam, and that of the fish that reach each dam, 

80 percent of those fish must pass within 36 hours, and the total passage should be 

85 percent of those fish that arrive at each dam.
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additional attraction flow capacity if needed; (4) restore the original design of 900-cfs 

attraction flow in the east lift; (5) add a second 3,300-gallon hopper in the east lift in the 

space provided for in the original design, and upgrade electrical and mechanical 

equipment to allow a 15-minute lift cycle time; (6) after restoration of the 900-cfs 

attraction flow and if 2 years of effectiveness studies at that flow show poor attraction to 

the lift, conduct a feasibility study for modifying the locations of entrances A and B; and 

(7) implement changes to entrances A and B if the feasibility study indicates it would be 

technically feasible and result in improved effectiveness. We also recommend a study on 

effects of gizzard shad on passage efficiency, capacity, and interference with American 

shad use of the Conowingo fish lifts. This study may provide information on how lift 

operations may be modified to discourage gizzard shad use of the lifts, or potential 

sorting mechanisms to separate the two species. 

Under the staff alternative, we recommend the above lift improvements so that 

trapping and trucking can be restored to the west lift as a primary function, along with the 

west lift’s secondary functions for collection of shad eggs and other experimental 

purposes, while the east lift would continue to operate as a volitional passage facility, to 

supply fish to upstream fish passage facilities. We conclude that, while this alternative 

would involve substantial costs (levelized annual cost of $959,760 for identified 

engineering costs, and $260 levelized annual cost for the gizzard shad study), it would 

enhance American shad restoration in the Susquehanna River in a phased and 

economically reasonable manner.

American Eel Passage

At the Muddy Run Project, Exelon incorporated the Pennsylvania DEP 

certification into its proposal for the project, which requires Exelon to implement 

Exelon’s American Eel Passage Plan, with all measures to occur at Conowingo. Thus, 

Exelon proposes upstream eel passage at Conowingo. That would include interim trap 

and truck facilities on the west side of the tailrace and another on the east side of the 

river, likely in Octoraro Creek. Those facilities would operate until 2030, when the 

facilities would be replaced with volitional passage facilities. Exelon also proposes to 

cooperate with other licensees on the lower Susquehanna River in implementing a 

downstream trap and transport program and conducting studies on eel passage from 

upstream of York Haven. Interior’s preliminary fishway prescription for Conowingo also 

requires construction of eel trapping and trucking and eventually volitional facilities on 

both shorelines. For downstream passage, Interior prescribes that Exelon maintain 

downstream eel passage survival rates of at least 85 percent through the Conowingo 

Project, with follow-up effectiveness studies to determine whether downstream passage 

rates are achieved. If not achieved, Exelon would evaluate changes in operation and fish 

guidance systems to provide safe, timely, and effective downstream fish passage. We are 

in agreement with the proposed and prescribed American eel passage measures and 

recommend that they become conditions of any license issued. One caveat that we 

recommend is that the transition to volitional passage at Conowingo not be set to a fixed 
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date (in the year 2030), but be based on a specific need. A trap and trucking program 

may still be viable past 2030 and it would give managers the option to stock specific 

watersheds that may not be available with volitional passage, or in the event volitional 

passage facilities at the three lower Susquehanna River projects are not highly effective. 

We estimate that the levelized annual cost for the trap and transport facilities would be 

$883,380, and the volitional facilities would be $467,400. The annualized cost for the 

downstream trap and transport program at Conowingo would be $203,140. While these 

costs would be substantial, they are justified because implementation of these measures 

would allow for upstream and downstream passage of the American eel, which has been 

excluded from the Susquehanna River since the original construction of Conowingo dam 

in 1928. 

Bald Eagle Management Plan

Exelon proposes and Interior recommends a measure to finalize and implement the 

Bald Eagle Management Plan filed with the license application that provides for the 

management of bald eagle habitat on Exelon lands at the Conowingo Project. The Bald 

Eagle Management Plan is based on recommendations from the FWS National Bald 

Eagle Management Guidelines and state agency guidance. It includes implementing 

distance and landscape buffers around nesting sites and avoiding certain activities during 

nesting season. In addition, the Bald Eagle Management Plan includes guidelines for 

activities around roosting and foraging areas. The plan also includes provisions for 

monitoring of nesting, roosting, and foraging sites every 5 years and injury and mortality 

procedures. Interior indicates two specific measures that Exelon should reconcile to 

avoid disturbance of eagle concentration areas: (1) enforcement of human traffic 

restrictions on both sides of Roland Island, under the towers in the river, and on the Cecil 

County side of the river where current human activities disturb perching and foraging 

eagles; and (2) a requirement that Exelon release information pertaining to federal 

regulations that protect eagles and great blue heron rookeries, and other migratory birds if 

any lands are potentially donated by Exelon.

We provide our analysis for recommending Exelon’s proposed Bald Eagle 

Management Plan in section 3.3.3.2, Terrestrial Resources, Environmental Effects. This 

section indicates implementation of the Bald Eagle Management Plan, as proposed by 

Exelon and recommended by Interior, would benefit bald eagles within the Muddy Run 

and Conowingo project boundaries by complying with bald eagle management guidelines 

and state guidelines, ensuring that future bald eagle nest, roost, and foraging areas are 

also protected by the bald eagle management plan, and ensuring that FWS and 

Pennsylvania Game Commission are aware of any project-related bald eagle mortality for 

the term of any new license. In addition, Interior’s recommendation for restrictions to 

human activity in the vicinity of eagle concentration areas would result in greater 

protection of foraging and communal roosting bald eagles from human disturbance. As 

such, we recommend the plan become a condition of any license issued for the project, 

with the addition of Interior’s recommendations for measures to minimize recreation-
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related disturbance in proximity to roosting or foraging eagles. As Exelon has not 

proposed to donate lands as part of the proposed project, it is not necessary at this time to 

include a measure in the proposed Bald Eagle Management Plan that would require 

Exelon to release information on bald eagles or other migratory species to a recipient. 

We estimate that the levelized annual cost of implementing the bald eagle management 

plan would be $1,740 and conclude the benefits of protecting bald eagles justify the cost 

associated with implementing the revised plan.

Osprey Management Policy

Exelon’s proposed osprey management policy, described in Conowingo’s 

proposed SMP, states that Exelon would work with state and federal agencies to provide 

appropriate buffers dictated by the types of activities carried out in either visual or 

auditory proximity to nests during breeding and nesting season (January to late July). 

This includes implementation of: (1) nest buffers during the breeding season of 330 feet 

for most activities and larger buffers up to 600 feet for activities with the potential to emit 

excessive noise (which excludes routine project operation and maintenance activities); 

(2) restrictions on herbicide application within 330 feet of osprey nests during breeding 

season; and (3) consultation with FWS and Pennsylvania Game Commission to 

determine BMPs and obtain applicable permits in the event an osprey nest on project 

transmission line towers is identified as a problem nest that needs to be removed or 

relocated. Our analysis in section 3.3.3.2, Terrestrial Resources, Environmental Effects, 

indicates implementation of the osprey management policy would benefit the osprey by 

enacting protection measures and following BMPs. Therefore, we recommend adopting 

this recommendation. The estimated annual cost of implementing the osprey 

management policy is included in the cost of implementing the SMP. 

Waterfowl Nesting Protection Plan

Interior recommends under section 10(j) that Exelon develop and implement a 

waterfowl nesting protection plan in consultation with FWS and file it with the 

Commission for approval. Such a plan would: (a) identify project-related effects on 

nesting waterfowl, such as flooding during nesting season; (b) identify which species of 

nesting waterfowl are affected, if any; and (c) if project-related effects are identified, 

establish appropriate protection or mitigation measures, in consultation with FWS. In our 

analysis in section 3.3.3.2, Terrestrial Resources, Environmental Effects, we conclude 

that implementation of a waterfowl nesting protection plan at the Conowingo Project 

would identify any specific areas that have nest flooding and allow appropriate protection 

or mitigation measures to be established. Overall, implementation of a waterfowl nesting 

protection plan at the Conowingo Project, in consultation with FWS and the state 

agencies, would benefit nesting waterfowl. We recommend adopting the plan and 

estimate that the levelized annual cost of implementing the waterfowl nesting protection 

plan would be $19,980. We find that the benefits of protecting nesting waterfowl at the 

project warrant the cost of developing and implementing a plan.
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Northern Map Turtle Protection Plan

Although Exelon did not propose any specific measures for the protection of 

northern map turtles at the project, Exelon has worked with Towson University and 

Maryland DNR to develop potential measures that could enhance the map turtle 

population; some of these measures (i.e., artificial basking platforms) are still 

experimental, however, and it may take several years to develop an optimal design. 

Other potential measures (i.e., restricting public access at Octoraro Beach during the 

nesting season and educating recreational boaters regarding the need to minimize 

disturbance of basking map turtles) may take several years to implement and additional 

time after that for any positive population trend to be documented. Negative effects, such 

as nest destruction and predation on incubation eggs, are likely to continue in the future. 

Consequently, a relatively long-term population monitoring program would be necessary 

to document whether implemented enhancements are resulting in the expected positive 

population effects. We recommend the development and implementation of a formal 

northern map turtle protection plan at the Conowingo Project, in consultation with 

Maryland DNR, that incorporates nest management and mitigation measures to create 

new alternative nesting and basking sites. There are numerous factors that contribute to 

the breeding success or failure of map turtles, and some may be project-related. The 

northern map turtle protection plan should include the development and implementation 

of nest management and alternate basking site mitigation and protection measures 

identified and studied during the ongoing Towson University map turtle studies; annual 

monitoring of the northern map turtle population at the Conowingo Project for 10 years; 

annual monitoring of the use and success of both the mitigation and protection measures 

for 10 years; an assessment of the northern map turtle’s response to any changes in 

operating regime as a result of any license issued; and methods of altering or amending 

protection and mitigation measures as a result of the monitoring, in consultation with 

Towson University and Maryland DNR. Our analysis in section 3.3.3.2, Terrestrial 

Resources, Environmental Effects, indicates that implementation of a northern map turtle 

protection plan would benefit the map turtle by increasing nesting success and providing

more stable basking sites. We estimate that the levelized annual cost of implementing the 

northern map turtle protection plan would be $14,830 and conclude the benefits of 

protecting northern map turtles justify the cost.

Recreation Management Plan

The Conowingo Project provides a variety of recreational resources, and Exelon 

developed a Recreation Management Plan and schedule for implementing proposed 

recreational enhancements at the Conowingo Project to enhance these resources. Exelon 

proposes to implement the proposed Recreation Management Plan to manage the project 

reaction facilities. As discussed in in section 3.3.5.2, Recreation and Land Use 

Resources, Environmental Effects, a recreation plan would allow Exelon to implement 

facility improvements and install new facilities in a coordinated manner, and would 

ensure that the proposed recreational facility improvements meet the intended purposes. 
396

However, the plan does not include a specific provision for reviewing and updating the 

plan over the term of any license issued. Similarly, the sedimentation of Peach Bottom 

Marina, Conowingo Creek, and Broad Creek on Conowingo Pond could compromise 

access at these locations. The staff alternative includes revising the plan to specify 

visitation and sedimentation monitoring, as well as consultation efforts as part of the 

plan. We recommend that the final Recreation Management Plan for the project include 

measures for conducting a recreation use study every 12 years throughout the license 

term, consistent with every other FERC Form 80 reporting period, to ensure the proposed 

plans are current and the sites are meeting the demand. We also recommend that Exelon

review and update the plan every 12 years in consultation with resource agencies, 

counties, and other interested stakeholders in the project area, such as Pennsylvania FBC, 

Pennsylvania DCNR, Maryland DOE, and Maryland DNR. We also agree with the 

current practice of maintaining a minimum level of 107.2 feet at Conowingo Pond during 

weekends between Memorial Day and Labor Day to ensure sufficient depths for boating 

activities over the term of any future license. We estimate the levelized annual cost of 

the final Recreation Management Plan would be $4,450. We conclude that this cost 

would be worth the substantial benefits that would be derived from implementing the 

plan as revised. 

Recreation Facility Improvements

Exelon proposes improvements at 13 recreation facilities. In our analysis in 

section 3.3.5.2, Recreation and Land Use Resources, Environmental Effects, we conclude 

that Exelon’s proposed boat ramp and boat launch enhancements at existing recreation 

facilities would provide significant improvements to the project’s recreational resources. 

Implementation of the proposed Sediment Management Plan, as discussed in section 

3.3.1, Geology and Soils, would, at a minimum, monitor the depth of sediment at Peter’s 

Creek (Peach Bottom Marina), Conowingo Creek, and Broad Creek (Harford County 

boat launch) every 5 years; however, the plan stops short of identifying at what depths the 

locations need to be dredged and scheduling dredging. These three boat ramps represent 

half of the boat ramps providing access to Conowingo Pond for motorized boating. 

Visitor survey results indicate that 6 percent of the comments received at Conowingo 

Creek targeted shallow water/dredging needs. Similarly, maintaining the minimum pond 

elevation at 107.2 feet on weekends between Memorial Day and Labor Day as currently 

required would ensure the boating resources are maintained through the term of any 

license. Cross-referencing the sediment monitoring proposed at the three access sites 

under the Sediment Management Plan into the final Conowingo Recreation Management 

Plan would ensure sediment monitoring results are included in discussions related to 

boater access to the reservoir. Development of a final Sediment Management Plan that 

includes detailed benchmarks for dredging, a schedule, and commitment to dredging the 

three access areas as soon as the benchmark sediment depths are reached would ensure 

that recreation access is not lost or compromised indefinitely. Implementation of the 

proposed improvements at Exelon’s recreation facilities would have an estimated 

levelized cost of $218,240 (not including the Sediment Management Plan, which is 
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discussed separately above). The benefit of safe, accessible, and well-maintained 

recreation facilities at this highly used reservoir warrants the annual cost of implementing 

these measures. 

Catwalk 

Exelon has closed the catwalk for angling since October 2001, citing security 

concerns related to public access in close proximity to the powerhouse. Maryland DNR 

and a number of citizens recommend reopening the catwalk for angler access. Exelon 

has denied these requests citing safety and security concerns and stated that the 

construction of the wharf at Fisherman’s Park and the new access at Octoraro Creek Park 

were provided to mitigate for the closure of the catwalk. Recreation use numbers 

collected by Exelon for Fisherman’s Park indicate the site is popular and provides both 

shore-based fishing, as well as boat launch opportunities to the river below the dam. 

Although not measured directly, the latent demand for angling from a re-opened catwalk 

could be comparable to, or higher than use at the upstream York Haven and Safe Harbor 

projects. We conclude in section 3.3.5.2, Recreation and Land Use Resources.

Environmental Effects, that the catwalk provides exceptional angling opportunities 

different from those currently provided at the new access sites. Angling from similar 

structures at upstream hydropower projects is both allowed (with minimal security 

measures) and popular. Comments during relicensing indicated that fishing from the 

shore at Fisherman’s Park is difficult as the main channel is far away and lures are 

pushed downstream and to the shore. The proximity of Conowingo dam to large 

population centers offers more anglers opportunities to fish this unique and historically 

popular resource. Providing this opportunity at Conowingo, even on a limited basis, 

would expand the diversity of angler opportunities by providing anglers access to fish the 

main channel under a range of operating conditions. Therefore, we recommend that 

Exelon revise its Recreation Management Plan to include a plan to reopen the catwalk on 

a limited basis (for example, the catwalk could be opened for fishing derbies, during 

holiday weekends, during peak fishing periods, or other occasions) that would be 

developed in consultation with interested stakeholders. We recommend that any plan to 

reopen the catwalk include security measures that address the vulnerability of the facility 

and the safety of the users of the catwalk. Such measures could include, but not be 

limited to, on-site inspections, video surveillance, pre-screening procedures, capacity 

limits, security personnel, and physical infrastructure modifications. The cost to safely 

reopen the catwalk to anglers would depend upon the number of days that the facility 

would be open to the public and the specific measures that would be implemented to 

ensure a safe and secure environment. We estimate that opening the catwalk on a limited 

basis would cost significantly less than the $141,390 levelized annual cost estimated by 

Exelon, which based its cost estimates on a 12 hours per day and 365-day per year 

opening and factored in reconstructing the catwalk to be ADA-compliant. We conclude 

that, from a recreational resource perspective, the costs would be worth the benefits. 

Nevertheless, the ultimate decision on whether the catwalk can be reopened to the public,
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even on a limited basis, would depend upon the Commission’s evaluation of the plan and 

whether it satisfies public safety and security concerns.

Shoreline Management

The Conowingo Project provides access to many recreational, natural, and 

shoreline resources within the lower Susquehanna River. Through a collaborative 

process, Conowingo developed a single shoreline management document to address 

concerns while maintaining provisions to protect shoreline environmental resources. 

Exelon proposes to implement the proposed SMP to manage the environmental 

resources around Conowingo Pond’s shore. As discussed in section 3.3.5.2, Recreation 

and Land Use Resources, Environmental Effects, the SMP would include specific 

measures and policies related to shoreline vegetation management, sediment and erosion

control, woody debris management, game species management, sensitive natural resource 

protection, recreation use, and use of project lands. We recommend including the SMP 

in any new license issued but with our recommended revisions for regular updates. 

Revising the SMP to include regular updates every 10 years in consultation with 

interested stakeholders, consistent with the latest Guidance for Shoreline Management 

Planning at Hydropower Projects (FERC 2012), would ensure the plan is harmonious 

with conditions at the project. We conclude that the addition of regular updates and 

consultation to the SMP would be worth the estimated levelized annual cost of $1,440.

Historic Properties Management Plan

Exelon proposes to implement the HPMP filed with the license application for the 

management of archaeological and historic resources throughout the term of any new 

license, including: (1) a schedule and methodology for completing any additional 

recommended studies and implementing monitoring measures; (2) management measures 

for identified historic properties including Conowingo dam and powerhouse; 

(3) protection of any historic properties threatened by project-related activities, including 

project operations, shoreline and aquatic recreation, shoreline development, routine 

project maintenance, and other project activities or operations; and (4) public outreach, 

education, and signage for the purpose of reducing looting and vandalism of sites, with 

staff modifications. As discussed in section 3.3.6.2, Cultural Resources, Environmental 

Effects, we conclude that the following revisions would make the HPMP more 

comprehensive and complete: (a) revise the project APE to include the narrow strip of 

land located in the current project boundary that extends downstream from Spencer 

Island along the west side of the river to the city of Havre de Grace, Maryland that

contains four additional previously recorded archaeological sites (18HA240, 18HA267, 

18HA268, 18HA269); (b) inventory any lands within the project APE (particularly AOIs 

identified in the Phase IA study that were not subject to Phase IB study), evaluate any 

identified cultural resources for National Register eligibility, and address potential affects 

prior to any sale or transfer of those lands; (c) make a good faith effort to obtain access to 

private property to conduct appropriate studies should project effects of any kind to 
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cultural resources on private lands be identified over a new license term; (d) discuss all 

48 sites identified to date within the project APE; (e) discuss all 27 historic structures 

identified in the APE or an explanation regarding why they need not be considered in the 

HPMP; (f) correctly identify the Susquehanna and Tidewater Canal and Columbia & Port 

Deposit Railroad as eligible for listing on the National Register; (g) revise the list (as 

necessary) of project activities involving the Conowingo Project system that can be 

completed without Maryland SHPO review; (h) include a process for how project-related 

ground-disturbing activities would be assessed to determine whether or not 

archaeological sites would be affected, particularly in areas that have not been subject to 

previous archaeological survey; (i) ensure confidentiality of cultural resources locational 

information during implementation of public outreach programs; and (j) include a 

description of project-related activities that would require consultation with the Delaware 

Nation and the Onondaga Nation in accordance with section 106 of the NHPA and 

documentation of consultation with Indian tribes. Our analysis in section 3.3.6.2, 

Cultural Resources, Environmental Effects, indicates implementation of the proposed 

HPMP with our recommended measures would ensure that the Conowingo Project would 

not adversely affect historic properties during the course of any license. We estimate that 

the levelized annual cost to revise and implement the HPMP for the project would be 

$37,080 and conclude the benefits of protecting cultural resources justify the cost.

Project Boundary

Exelon proposes to remove 1,965 acres from the Conowingo Project boundary that 

includes areas that were necessary during construction of the project but are no longer 

needed for project purposes. As discussed in section 3.3.5.2, Recreation and Land Use

Resources, Environmental Effects, removing these lands would remove four non-project 

recreation facilities from the project boundary, including the Lower Susquehanna 

Heritage Greenway, Deer Creek Access, Lapidum Boat Launch, and McLhinney Park. A 

relatively thin ribbon of land on the west bank downstream of Conowingo dam was 

included in past licenses so as to include the railroad that was used to shuttle material to 

the dam during construction. While the lands in this area are now used for non-project 

recreation, these lands serve no direct project purpose. Project recreation demand is 

currently met through 15 project recreation sites located around Conowingo Pond and 

immediately downstream. Continuation of the lease agreements with the State of 

Maryland for Susquehanna State Park (which includes the Lower Susquehanna Heritage 

Greenway Trail, Deer Creek Access, and Lapidum Boat Launch) and the City of Havre 

de Grace for McLhinney Park would maintain recreation access at these locations. 

Removal of the 1,965 acres of lands would be consistent with FERC policy that only 

lands and waters needed for project purposes should be included in the project boundary. 

Lands and waters needed may include those for (1) construction and operation of its 

project, and (2) to carry out other project purposes such as recreation, wildlife protection, 

and enhancement. While these lands provide recreation opportunities, these opportunities 

are not related to the project. In addition, removing these non-project recreation sites 

from the project boundary would not limit the recreation opportunities available in the 
400

area downstream of Conowingo dam. Execution of a new lease with Maryland DNR 

would ensure these lands are maintained for public recreation purposes; however, they 

would not be under FERC jurisdiction. Because the lands proposed for removal from the 

Conowingo project boundary are no longer used for project purposes, removing these 

lands would be consistent with Commission policy. 

5.1.3.3 Measures Not Recommended

TNC Flow Regime

We do not recommend adopting Interior’s recommendation for implementing the 

TNC Flow Regime or a Maryland DOE certification, if more restrictive. Our reasons for 

not adopting are discussed in section 5.1.3.2, Conowingo Project, Additional Measures 

Recommended by Staff for Conowingo, Instream Flows. Our recommendation for a 

modified flow regime, however, is based on the TNC criteria for the habitat persistence 

analysis that the range of flows during peaking operation provides the TNC target of 70

percent of MWUA by month. Our primary reason for not adopting the TNC Flow 

Regime is the benefits to some species life stages would not justify the effects on project 

operation and costs, with a levelized annual cost of $329,130. Operation under the TNC 

Flow Regime would be restrained and would eliminate many of the peaking and ancillary 

services benefits to the PJM region from the Conowingo Project, and only provide 

minimal benefit to the downstream habitat for some species while negatively affecting

other species. Ancillary services include those services necessary to maintain the 

reliability of the interconnected transmission system. Flow requirements of any future 

Maryland DOE certification are not known at this time, and cannot be analyzed.

Upstream Fish Passage – Alternative G

We do not recommend adopting Interior’s recommendation for implementing the 

fishway prescription detailed as Alternative G. Our reasons for not adopting this measure 

are given in section 5.1.3.2, Conowingo Project, Additional Measures Recommended by 

Staff for Conowingo, Upstream Fish Passage. 

Fish Stranding 

Exelon is proposing to continue the same ramping rates of about 70,000 to 

80,000 cfs per hour or less and maximum generating flows as currently operated. To 

address fish stranding, the Nature Conservancy recommends the implementation of 

ramping rates as part of its TNC Flow Regime. Under the TNC Flow Regime, the 

maximum generating flow would be limited to 65,000 cfs from March through 

September, upramping rates would be limited to 40,000 cfs per hour year-round, and 

downramping rates would be limited to 20,000 cfs per hour overall, and 10,000 cfs from 

July through September, if flows are less than 30,000 cfs. Interior’s prescription includes 

a maximum downramping rate of 20,000 cfs/hour. Interior prescribes and the 

Pennsylvania FBC recommends channel modifications to eliminate stranding in the 
401

spillway channel. We provide our analysis of the effects of ramping rates and channel 

modifications on fish stranding downstream of the Conowingo dam in section.3.3.2.2,

Water Resources, Environmental Effects. Our assessment of stranding below the project 

indicates that few fish are killed by stranding under existing operation, and about 90 

percent of those killed were gizzard shad, carp, and catfish species, with few diadromous 

fish impacted. We concluded that the existing changes in flow levels are not having 

significant adverse effects on aquatic resources, and that maximum flows from the 

project (86,000 cfs) generally remain within the TNC target of 70 percent of MWUA for 

the key life stages analyzed. Restraining ramping rates to those recommended in the 

TNC Flow Regime would adversely affect project operation by limiting the project’s 

ability to respond to changes in load in the PJM system, reducing the ancillary services 

benefits of the project. There would also be minimal benefit in implementing the 

Pennsylvania FBC recommendation to extend the retaining wall at the east end of the east 

fish lift, add boulder fill in that area to prevent generation flow from flooding the 

spillway pool at high levels of generation, or dredge a channel(s) from the spillway pool 

area to downstream areas to provide egress for stranded fishes. Implementing these 

structural measures downstream of Conowingo dam would have a relatively high cost 

(levelized annual cost of $74,100), would involve in-river construction activities that 

would affect both fish and wildlife usage of the area, but would benefit only a small 

number of fish. Therefore, we are not recommending the imposition of ramping rates, 

lower maximum discharges, or structural measures to reduce the potential for fish 

stranding. While we do not find that stranding is an issue requiring mitigation 

downstream of Conowingo dam, we acknowledge that Interior’s downramping provision 

in its final prescription would become a condition of any license issued for the project. 

Bog Turtle Management Plan

Interior states that bog turtles have been observed close to Conowingo dam and 

recommends a bog turtle management plan; however, it has yet to provide evidence to 

indicate that bog turtles are present within the Conowingo Project boundary. Thus, staff 

cannot presently determine if bog turtles would be affected by the Conowingo Project. 

Further consultation with Interior is necessary to determine the potential for project 

effects and the need for Interior’s recommended bog turtle management. Therefore, we 

do not recommend a bog turtle management plan for the Conowingo Project. 

5.2 UNAVOIDABLE ADVERSE EFFECTS

Fluctuations in reservoir levels would continue to result in unavoidable minor 

bank erosion for all three projects (York Haven, Muddy Run, and Conowingo). In 

addition, natural high-flow events would continue to mobilize bed substrate downstream 

of Conowingo dam. 

Unless the current annual sediment load of 3 million tons is dredged from the 

reservoirs annually, Conowingo Pond would likely be filled with sediment sometime 

between years 2023 and 2038, and the full sediment load carried by the Susquehanna 
402

River would again reach Chesapeake Bay, as it did prior to the construction of the lower 

river reservoirs from 1910 to 1930. 

The York Haven Project would result in the unavoidable loss of vegetation and 

wildlife habitat during construction of the nature-like fishway within the construction 

footprint. At both the Muddy Run and Conowingo projects, the proposed projects would 

result in the unavoidable loss of vegetation and wildlife habitat during the expansion of 

recreation facilities.

5.3 FISH AND WILDLIFE AGENCY RECOMMENDATIONS

Under the provisions of section 10(j) of the FPA, each hydroelectric license issued 

by the Commission shall include conditions based on recommendations provided by 

federal and state fish and wildlife agencies for the protection, mitigation, and 

enhancement of fish and wildlife resources affected by the project. In response to our 

REA notice, Interior filed recommendations for all three projects on 

January 30 and 31, 2014. Pennsylvania FBC filed recommendations for the Conowingo 

Project on December 11, 2013.

Section 10(j) of the FPA states that whenever the Commission believes that any 

fish and wildlife agency recommendation is inconsistent with the purposes and the 

requirements of the FPA or other applicable law, the Commission and the agency will 

attempt to resolve any such inconsistency, giving due weight to the recommendations, 

expertise, and statutory responsibilities of such agency. Table 5-1 lists the federal and 

state recommendations filed subject to section 10(j), and whether the recommendations 

are adopted under the staff alternative. Environmental recommendations that we consider 

outside the scope of section 10(j) have been considered under section 10(a) of the FPA 

and are addressed in the specific resource sections of this document and the 

previous section.

For the York Haven Project, Interior made two recommendations that we consider 

within the scope of section 10(j), and we adopt both. For the Muddy Run Project, 

Interior made five recommendations, two of which we consider within the scope of 

section 10(j), and we adopt all five recommendations. For the Conowingo Project, 

Interior made nine recommendations, six of which we consider within the scope of 

section 10(j), and Pennsylvania FBC made 13 recommendations, nine of which we 

consider within the scope of section 10(j). We adopt five of Interior’s recommendation 

and nine of Pennsylvania FBC’s recommendations.

The Commission staff makes a preliminary determination that three 

recommendations by Interior and five recommendations by Pennsylvania FBC for the 

Conowingo Project may be inconsistent with the purpose and requirements of the FPA or 

other applicable law. 
403

Table 5-1. Fish and wildlife agency recommendations for the Susquehanna River 

Projects (Source: staff).

Recommendation Agency

Within the 

Scope of 

Section 10(j) Annual Cost Adopted?

York Haven Project

1. To help evaluate safe 

and effective passage of 

American eels through 

the project, cooperate 

with FWS and other 

interested parties in the 

funding, planning and 

conduct of a lower 

Susquehanna River 

downstream eel study to 

evaluate the timing, 

magnitude, duration, 

annual variation, and 

environmental conditions 

associated with the 

active migration of silver 

eels through the 

Susquehanna River to 

the Chesapeake Bay

Interior Yes $5,550 Yes

2. Operate to maintain an 

instantaneous minimum 

flow below the project of 

1,000 cfs or inflow, 

whichever is less; an 

average daily flow of 

2,500 cfs or inflow, 

whichever is less; 

whenever river flow is 

less than 3,000 cfs, 

operate as run of river; 

and provide for 

temporary modifications 

resulting from operating 

exigencies beyond the 

control of the licensee. 

Interior Yes $0 Yes 
404

Recommendation Agency

Within the 

Scope of 

Section 10(j) Annual Cost Adopted?

Muddy Run Project

1. Before starting any 

ground-disturbing work, 

visit the FWS 

Chesapeake Bay Field 

Office and Pennsylvania 

Field Office websites 

and follow the Bog 

Turtle and Bald Eagle 

management guidelines.

Interior No. Not a 

specific 

measure to 

protect, 

mitigate, or 

enhance fish 

and wildlife 

resources.

$0 Yes

2. Develop and implement 

a bog turtle management 

plan.

Interior Yes $8,240 Yes 

3. Finalize and implement 

the Bald Eagle 

Management Plan and as 

part of the licensee’s 

compliance under the 

Bald and Golden Eagle 

Protection Act, FERC 

should require the 

licensee to follow 

conservation measures 

that protect bald eagles 

in addition to adopting 

the National Bald Eagle 

Management Guidelines.

Interior Yes $750 Yes

4. Develop and implement 

an SMP.

Interior No. Not a 

specific 

measure to 

protect, 

mitigate, or 

enhance fish 

and wildlife 

resources.

$1,440 Yes

5. The project shall be 

subject to inspection by 

FWS to ensure 

compliance with 

protection, mitigation, 

and enhancement 

measures.

Interior No. Not a 

specific

measure to 

protect, 

mitigate, or 

enhance fish 

and wildlife 

resources.

$0 Yes
405

Recommendation Agency

Within the 

Scope of 

Section 10(j) Annual Cost Adopted?

Conowingo Project

1. Early in the planning 

process for any grounddisturbing work, visit the 

FWS Chesapeake Bay 

Field Office and 

Pennsylvania Field 

Office websites and 

follow the Bog Turtle 

and Bald Eagle 

Management Guidelines.

Interior No. Not a 

specific 

measure to 

protect, 

mitigate, or 

enhance fish 

and wildlife 

resources.

$0 Yes

2. Develop and implement 

a bog turtle management 

plan.

Interior Yes $8,240 No

3. Finalize and implement 

the Bald Eagle 

Management Plan and as 

part of the licensee’s 

compliance under the 

Bald and Golden Eagle 

Protection Act, FERC 

should require the 

licensee to follow 

conservation measures 

that protect bald eagles 

in addition to adopting

the National Bald Eagle 

Management Guidelines.

Interior Yes $1,740 Yes

4. Develop and implement 

an SMP.

Interior No. Not a 

specific 

measure to 

protect, 

mitigate, or 

enhance fish 

and wildlife 

resources.

$1,440 No
406

Recommendation Agency

Within the 

Scope of 

Section 10(j) Annual Cost Adopted?

5. Prepare, develop, and 

implement a study to 

evaluate safe and 

effective downstream 

passage of American eels 

through the project. 

Coordinate with FWS 

and other interested 

parties in the funding, 

planning and conduct of 

a lower Susquehanna 

River downstream eel 

study to evaluate the 

timing, magnitude, 

duration, annual 

variation, and 

environmental conditions 

associated with the 

active migration of silver 

eels through the 

Susquehanna River to 

the Chesapeake Bay

Interior Yes $5,550 Yes

6. Project shall be subject 

to inspection by FWS to 

ensure compliance with 

protection, mitigation, 

and enhancement 

measures.

Interior No. Not a 

specific 

measure to 

protect, 

mitigate, or 

enhance fish 

and wildlife 

resources.

$0 Yes

7. Prepare and implement 

waterfowl nesting 

protection plan.

Interior Yes $19,980 Yes
407

Recommendation Agency

Within the 

Scope of 

Section 10(j) Annual Cost Adopted?

8. Finalize and implement a 

flow management plan

and implement the flow 

recommendations of The 

Nature Conservancy or 

the Maryland DOE 

certification, whichever 

is more restrictive to 

return river to more 

natural conditions 

downstream.

Interior Yes $332,090 No

9. Install and operate 

fishways as described in 

Interior’s preliminary 

section 18 prescription 

Alternative G.

Interior Yes $3,685,040 No

1. Incorporate performance 

criteria into new license 

where 80% of the shad 

that enter the project area 

must pass the project 

within 5 days, to be 

based on telemetry study 

of 150 shad per year for 

3 years. If goal is not 

reached, initiate 

operational changes as 

specified by the agencies 

and test for 3 years using 

telemetry study. If goal 

is still not reached after 3 

years, make structural 

changes to the fish lifts 

as specified by the 

agencies, and test for an 

additional 3 years using 

telemetry study. If goal 

is still not reached within 

3 years, additional 

structural changes may 

be required, depending 

on behavior of tagged 

shad.

Pennsylvania 

FBC

Yes $22,230 No
408

Recommendation Agency

Within the 

Scope of 

Section 10(j) Annual Cost Adopted?

2. Modify east fish lift to 

include a larger hopper, 

increased attraction flow, 

and addition of a 

collection gallery in front 

of units 8-11.

Pennsylvania 

FBC

Yes $0 Adopt 

larger 

hopper 

and 

increased 

attraction 

flow. Not 

adopt 

collection 

gallery.

3. Complete the rebuild of 

the west fish lift to 

include additional 

attraction water and 

provision to expand to 

volitional passage if 

needed. Ultimately, fish 

passage facilities at 

Conowingo will need to 

pass a design population 

of 5 million fish, and fish 

lifts will be required on 

both sides of the tailrace.

Pennsylvania 

FBC

Yes $0 No

4. Telemetry study of 

gizzard shad is needed to 

understand the issues of 

passage efficiency, 

capacity, and 

interference with 

American shad.

Pennsylvania 

FBC

No. Study 

could have 

been done prelicensing.

$260 Yes

5. Telemetry study to 

understand recycling of 

gizzard shad in the west 

fish lift.

Pennsylvania 

FBC

No. Study 

could have 

been done prelicensing.

$095 Yes

 

95 We assume the studies recommended in Pennsylvania FBC recommendations 

4 and 5 would be combined and conducted at the same time. As such, the estimated 

levelized cost for recommendation 4 would cover the cost for recommendation 5.
409

Recommendation Agency

Within the 

Scope of 

Section 10(j) Annual Cost Adopted?

6. Downstream passage 

survival of juvenile shad 

must be 95% or higher.

Pennsylvania 

FBC

No. Not a 

specific 

measure to 

protect, 

mitigate, or 

enhance fish 

and wildlife 

resources.

$0 No

7. Construct eel passage 

facility near west fish 

lift, with capability to 

modify the location of 

the facility and to change 

to volitional passage.

Pennsylvania 

FBC

Yes $442,340 Yes 

8. Test additional locations 

for eel passage near the 

west fish lift.

Pennsylvania 

FBC

Yes $0 Yes

9. Test additional locations 

for eel passage near the 

east fish lift and 

construct permanent 

traps as needed.

Pennsylvania 

FBC

Yes $0 Yes

10. Test additional capture 

locations on Octoraro 

Creek at base of 

Octoraro reservoir dam, 

and install additional 

traps there. 

Pennsylvania 

FBC

Yes $0 Yes

11. Transport 1 million eels 

annually from 2015 to 

2030 to sites above 

Conowingo and York 

Haven dams until 

permanent volitional 

facilities are operating 

effectively.

Pennsylvania 

FBC

Yes $0 No
410

Recommendation Agency

Within the 

Scope of 

Section 10(j) Annual Cost Adopted?

12. Once sufficient eels are 

in the system, cooperate 

with other utilities to 

conduct a study on eel 

downstream passage and 

ensure downstream 

passage survival of 80% 

at Conowingo for silver 

eels. Make operational 

and structural 

modifications as needed 

to achieve 80% survival.

Pennsylvania 

FBC

No. Not a 

specific 

measure to 

protect, 

mitigate, or 

enhance fish 

and wildlife 

resources. 

$203,140 Yes

13. Exelon should reduce 

stranding of migratory 

fish by (1) extending the 

retaining wall at the east 

end of the east fish lift or 

adding boulder fill in 

that area to prevent 

generation flow from 

flooding the spillway 

pool at high levels of 

generation, or (2) 

dredging a channel(s) 

from the spillway pool 

area to downstream areas 

to provide egress for 

stranded fishes.

Pennsylvania 

FBC

Yes $74,100 No (see 

section 

5.1.3.3)

We do not recommend adopting Interior’s recommendation for a bog turtle 

management plan. As we discuss in section 5.1.3.3, Conowingo Project, Measures Not 

Recommended, Interior states that bog turtles may be found in the project area, but we 

have not found evidence in the record to indicate that bog turtles are present within the 

Conowingo Project boundary. We estimate a levelized annual cost of $8,240 for this 

plan, which may not be needed. Based on this information, we find that Interior’s

recommendation to prepare a bog turtle management plan may be inconsistent with the 

comprehensive planning standard of section 10(a) and the equal consideration provision 

of section 4(e) of the FPA.

We do not recommend adopting Interior’s recommendation for a flow 

management plan and for implementing the flow recommendations of The Nature 

Conservancy or the Maryland DOE certification, whichever is more restrictive to return 
411

the river to more natural conditions downstream of Conowingo. As we discuss in section 

5.1.3.3, Conowingo Project, Measures Not Recommended, our analysis found that the 

TNC Flow Regime would not provide substantially more aquatic habitat benefits than the 

staff-recommended flow regime, but would have a substantial levelized annual cost of 

$329,130, and would eliminate many of the peaking and ancillary services benefits to the 

PJM region from the Conowingo Project. Flow requirements of any future Maryland 

DOE certification are not yet known. Based on this information, we find that Interior’s 

recommendation to implement a flow management plan and the TNC Flow Regime, or a 

yet unknown flow requirement of any Maryland DOE certification, may be inconsistent 

with the comprehensive planning standard of section 10(a) and the equal consideration

provision of section 4(e) of the FPA.

We do not recommend adopting Interior’s recommendations for installing and 

operating fishways as described in Interior’s preliminary section 18 prescription 

Alternative G. As we discuss in section 5.1.3.2, Conowingo Project, Additional 

Measures Recommended by Staff for Conowingo, Upstream Fish Passage, implementing 

the full suite of fish passage measures under Alternative G would not be needed at this 

time and would be costly, with a levelized annual cost of $2,334,260. We are 

recommending some fish passage improvements at the project that would still enhance 

upstream fish passage but at a substantially lower cost. Based on this information, we 

find that Interior’s recommendation to install and operate fishways as described in 

Interior’s preliminary section 18 prescription Alternative G may be inconsistent with the 

comprehensive planning standard of section 10(a) and the equal consideration provision 

of section 4(e) of the FPA.

We do not recommend adopting Pennsylvania FBC’s recommendation to 

incorporate performance criteria into any new license where 80 percent of the shad that 

enter the project area must pass the project within 5 days, along with additional studies to 

test that performance that would be followed up by more studies and operational and 

structural changes over a period of 12 years. As we discuss in section 5.1.3.2, 

Conowingo Project, Additional Measures Recommended by Staff for Conowingo,

Upstream Fish Passage, intensive fish passage studies have already been conducted at 

Conowingo dam over a period of decades, and we are recommending a suite of fish 

passage improvements at the project that would enhance upstream fish passage, and that 

would be implemented without further delay due to additional studies. Based on this 

information, we find that Pennsylvania FBC’s recommendation to incorporate 

performance criteria and conduct many more years of studies may be inconsistent with 

the comprehensive planning standard of section 10(a) and the equal consideration 

provision of section 4(e) of the FPA.

We do not recommend adopting Pennsylvania FBC’s recommendation to modify

the east fish lift by adding a collection gallery in front of units 8 to 11. As we discuss in 

section 5.1.3.2, Conowingo Project, Additional Measures Recommended by Staff for 

Conowingo, Upstream Fish Passage, there is insufficient justification to make major 

structural changes to the entrances to the east fish lift at this time; these changes would be 
412

costly with a levelized annual cost likely similar to that estimated for Interior’s 

recommendation for improvements to the east fish lift entrances ($852,190). We are 

recommending improvements to the entrances only if additional studies, after 

implementing our recommended improvements, find that effectiveness remains low. 

Based on this information, we find that Pennsylvania FBC’s recommendation to construct 

a collection gallery on the east fish lift may be inconsistent with the comprehensive 

planning standard of section 10(a) and the equal consideration provision of section 4(e) 

of the FPA.

We do not recommend adopting Pennsylvania FBC’s recommendation to 

complete the rebuild of the west fish lift to include additional attraction water and 

provision to expand to volitional passage, if needed, with an ultimate total design 

population of 5 million fish at the project. As we discuss in section 5.1.3.2, Conowingo 

Project Resources, Additional Measures Recommended by Staff for Conowingo,

Upstream Fish Passage, implementing the full range of fish passage facilities 

recommended by Pennsylvania FBC, would not be needed at this time and would be 

costly with a levelized annual cost likely similar to that estimated for Interior’s 

recommendation ($2,334,260). We are recommending some fish passage improvements 

at the project that would still enhance upstream fish passage but at a substantially lower 

cost. Based on this information, we find that Pennsylvania FBC’s recommendation to 

complete the rebuild of the west fish lift and install facilities with a total design 

population of 5 million fish may be inconsistent with the comprehensive planning 

standard of section 10(a) and the equal consideration provision of section 4(e) of 

the FPA. 

We do not recommend adopting Pennsylvania FBC’s recommendation to transport 

1 million eels annually from 2015 to 2030 to sites above Conowingo and York Haven 

dams until permanent volitional facilities are operating effectively. There is no indication 

that 1 million eels are currently available in the lower Susquehanna River for capture and 

transport, and requiring this specific design population for any eel trap and transport 

program would require Exelon to expend an unknown amount of effort and financial 

resources in an attempt to meet this requirement. Based on this information, we find that 

Pennsylvania FBC’s recommendation to require an American eel design population of 

1 million fish to transport may be inconsistent with the comprehensive planning standard 

of section 10(a) and the equal consideration provision of section 4(e) of the FPA. 

We do not recommend adopting Pennsylvania FBC’s recommendation to reduce 

stranding of migratory fish by (1) extending the retaining wall at the east end of the east 

fish lift or adding boulder fill in that area to prevent generation flow from flooding the 

spillway pool at high levels of generation, or (2) dredging a channel(s) from the spillway 

pool area to downstream areas to provide egress for stranded fishes. As we discuss in 

section 5.1.3.3, Conowingo Project, Measures not Recommended, our analysis found that 

few fish are currently being stranded under existing project operation, and there would be 

no need for implementing measures to reduce stranding, at a relatively high levelized 

annual cost of $74,100. Based on this information, we find that Pennsylvania FBC’s 
413

recommendation to make structural changes downstream of Conowingo dam to reduce 

fish stranding may be inconsistent with the comprehensive planning standard of section 

10(a) and the equal consideration provision of section 4(e) of the FPA.

5.4 Consistency with Comprehensive Plans

Section 10(a)(2)(A) of the FPA, 16 U.S.C.§803(a)(2)(A) (2006), requires the 

Commission to consider the extent to which a project is consistent with the federal or 

state comprehensive plans for improving, developing, or conserving a waterway or 

waterways affected by the project. We reviewed 26 comprehensive plans listed below 

that are applicable to the Susquehanna River Projects, located in Pennsylvania and 

Maryland. No inconsistencies were found.

Atlantic States Marine Fisheries Commission. 1995. Interstate fishery management plan 

for Atlantic striped bass. (Report No. 24). March 1995.

Atlantic States Marine Fisheries Commission. 1998. Interstate fishery management plan 

for Atlantic striped bass. (Report No. 34). January 1998.

Atlantic States Marine Fisheries Commission. 1998. Amendment 1 to the Interstate 

fishery management plan for Atlantic sturgeon (Acipenser oxyrhynchus). 

(Report No. 31) July 1998.

Atlantic States Marine Fisheries Commission. 1999. Amendment 1 to the Interstate 

Fishery Management Plan for shad and river herring. (Report No. 35). 

April 1999.

Atlantic States Marine Fisheries Commission. 2000. Technical Addendum 1 to 

Amendment 1 of the Interstate Fishery Management Plan for shad and river 

herring. February 9, 2000.

Atlantic States Marine Fisheries Commission. 2000. Interstate Fishery Management 

Plan for American eel (Anguilla rostrata). (Report No. 36). April 2000.

Atlantic States Marine Fisheries Commission. 2009. Amendment 2 to the Interstate 

Fishery Management Plan for shad and river herring. Arlington, Virginia. May 

2009.

Atlantic States Marine Fisheries Commission. 2010. Amendment 3 to the Interstate 

Fishery Management Plan for shad and river herring. Arlington, Virginia. 

February 2010.

Maryland Department of Natural Resources. 1984. Maryland rivers study – final report. 

Annapolis, Maryland. July 1984. (Conowingo Project only)
414

Maryland Department of State Planning. 1983. Maryland recreation and open space 

plan, Report V: strategy and summary. Annapolis, Maryland. September 1983.

(Conowingo Project only)

National Marine Fisheries Service. 1998. Final Recovery Plan for the shortnose 

sturgeon (Acipenser brevirostrum). Prepared by the Shortnose Sturgeon Recovery 

Team for the National Marine Fisheries Service, Silver Spring, Maryland. 

December 1998.

National Oceanic and Atmospheric Administration. 1980. Pennsylvania coastal zone 

management program and final environmental impact statement. Department of 

Commerce, Washington, D.C. August 1980.

National Park Service. 1993. The nationwide rivers inventory. Department of the 

Interior, Washington, D.C. 

National Park Service. 2010. Comprehensive management plan and environmental 

assessment for the Captain John Smith Chesapeake National Historic Trail. 

Annapolis, Maryland. September 2010.

Pennsylvania Department of Environmental Resources. 1983. Pennsylvania State water 

plan. Harrisburg, Pennsylvania. January 1983. 20 volumes.

Pennsylvania Department of Environmental Resources. 1986. Pennsylvania’s recreation 

plan, 1986-1990. Harrisburg, Pennsylvania.

Pennsylvania Department of Environmental Resources. 1988. Pennsylvania 1988 water 

quality assessment. Harrisburg, Pennsylvania. April 1988. Three volumes.

Pennsylvania Department of Environmental Resources. 1990. The Pennsylvania scenic 

rivers program scenic rivers inventory. Harrisburg, Pennsylvania. April 1990.

Susquehanna River Basin Commission. 2012. Comprehensive plan for the water 

resources of the Susquehanna River Basin. Harrisburg, Pennsylvania. June 2012.

U.S. Fish and Wildlife Service. 1989. Chesapeake Bay striped bass management plan. 

Annapolis, Maryland. December 1989.

U.S. Fish and Wildlife Service. 1989. Chesapeake Bay Alosid (shad and river herring) 

management plan. Annapolis, Maryland. July 1989.

U.S. Fish and Wildlife Service. 1992. Chesapeake Bay American eel fishery 

management plan. Annapolis, Maryland. December 18, 1992.
415

U.S. Fish and Wildlife Service. 2010. Migratory fish management and restoration plan 

for the Susquehanna River Basin. Harrisburg, Pennsylvania. November 15, 2010.

U.S. Fish and Wildlife Service. 2013. The American eel restoration plan for the 

Susquehanna River Basin. Addendum to the 2010 migratory fish management and 

restoration plan for the Susquehanna River Basin. Harrisburg, Pennsylvania. 

December 5, 2013.

U.S. Fish and Wildlife Service. Canadian Wildlife Service. 1986. North American 

waterfowl management plan. Department of the Interior. Environment Canada. 

May 1986.

U.S. Fish and Wildlife Service. Undated. Fisheries USA: the recreational fisheries 

policy of the U.S. Fish and Wildlife Service. Washington, D.C.
416

6.0 LITERATURE CITED

Allen, D.C. and C.C. Vaughn. 2010. Complex hydraulic and substrate variables limit 

freshwater mussel species richness and abundance. Journal of the North American 

Benthological Society 29(2): 383-394.

Ashton, M.J. 2009. Recent mussel surveys in the Susquehanna River below Conowingo 

Dam, Maryland. Ellipsaria 11(3): 12. 

ASMFC (Atlantic States Marine Fisheries Commission). 2010. Amendment 3 to the 

Interstate Fishery Management Plan for Shad and River Herring (American Shad 

Management). Approved February 2010.

Ashton, M. 2011. Results from ongoing freshwater mussel surveys in the Susquehanna 

River and the first collection of Dreissena polymorpha below Conowingo Dam, 

Maryland. Ellipsaria, Newsletter of the Freshwater Mollusk Conservation Society. 

Volume 13, number 1, March 2011. 

Bell, M.C. 1991. Fisheries Handbook of Engineering Requirements and Biological 

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7.0 LIST OF PREPARERS

Federal Energy Regulatory Commission

Emily Carter—Project Coordinator, Recreation and Land Use, Cultural Resources, and 

Aesthetics (Environmental Biologist; Masters of Natural Resources; A.B., 

Environmental Studies)

Andy Bernick—Terrestrial Resources, Threatened and Endangered Species, and Mussels 

(Wildlife Biologist, Ph.D, Ecology, Evolutionary Biology, and Behavior; B.S., 

Wildlife Biology and Management)

Monir Chowdhury—Geology and Soils, Water Resources (Water Quality), 

Socioeconomics, Engineering, Need for Power and Developmental Analysis 

(Engineer; Ph.D and M.S., Environmental Engineering; B.S., Civil Engineering, 

P.E.) 

Woohee Choi—Water Resources and GIS (Environmental Engineer; Ph.D and M.S., 

Civil and Environmental Engineering; B.S., Civil Engineering)

John Mudre—Water Resources (Ecologist; Ph.D., Fisheries Science)

Louis Berger Group

Patricia Weslowski—Task Management, Cultural Resources (Preservation Planner; 

Masters of Public Administration)

Holly Bender—Socioeconomics (Senior Economist; PhD and M.S., Mineral Economics, 

B.A., Economics and Political Science)

Brian Csernak – Terrestrial Resources (Environmental Scientist; M.S., Environmental 

Science and Policy; B.S., Biology) 

Sue Davis—Terrestrial Resources and Threatened and Endangered Species (Terrestrial 

Biologist; B.S., Wildlife Management)

Chris Dixon—Socioeconomics (Planner; MURP, Urban and Regional Planning, M.B.A., 

Business Administration; B.S., Environmental Economics and Management)

Peter Foote—Fisheries and Water Quality (Senior Fisheries Biologist; M.S., Fisheries 

Biology; B.S., Wildlife Biology)

Bernward Hay—Water Resources (Principal Environmental Scientist; Ph.D., 

Oceanography (Marine Geology); M.S., Geological Sciences and Remote 

Sensing)
429

Doug Hjorth—Quality Control (Principal Scientist; M.A. Biology; B.S., Fisheries 

Biology)

Kenneth Hodge—Need for Power and Developmental Analysis (Senior Engineer; B.S., 

Civil Engineering)

Alison Macdougall—Cultural Resources (Senior Environmental Manager; B.A., 

Anthropology)

Drew Miller—Mussels (Aquatic Biologist; Ph.D, Aquatic Biology; M.S., Aquatic 

Biology; B.S., Biology)

Tyler Rychener—GIS, Terrestrial (Environmental Scientist/GIS; M.S., Plant Biology; 

B.S., Biology)

Denise Short—Editorial Review (Technical Editor; M.S., Agriculture, Food, and the 

Environment; B.A., English)

Jot Splenda—Recreation and Land Use, Aesthetics (Environmental Planner; M.E.S.M, 

Water Resource Management; B.S., Ecology and Evolution)

Heather Unger—Bog Turtles (Project Scientist; B.S., Environmental Resources 

Management)
8.0 LIST OF RECIPIENTS

David R Poe, Partner

Bracewell & Giuliani LLP

2000 K Street NW

Washington, DC 20006

Jill Dinneen, Attorney

1 Capital Plaza

Concord, NH 03302

Jay T Ryan, Partner

Baker Botts, LLP - The Warner

1299 Pennsylvania Avenue, NW

Washington, DC 20004

Mark Bryer,

Nature Conservancy

5410 Grosvenor Lane, Suite 100

Bethesda, MD 20814

John A Whittaker

Winston & Strawn LLP

1700 K St. NW

Washington, DC 20006

Shawn A Seaman, Program Manager

Maryland Dept of Natural Resources

Tawes State Office Building

580 Taylor Ave., B-3

Annapolis, MD 21401

Kevin Mendik, ESQ, 

NPS Hydro Prgm Coord

U.S. National Park Service

15 State Street 10th floor

Boston, MA 02109

Rupak Thapaliya, Coordinator

Hydropower Reform Coalition

1101 14th St NW, Suite 1400

Washington, DC 20005

M. Curtis Whittaker, Partner

Rath, Young & Pignatelli

One Capital Plaza

Box 1500

Concord, NH 03302

Richard A. Cairo, General Counsel

Susquehanna River Basin Commission

4423 North Front Street

Harrisburg, PA 17102

Robert G. Grassi, Senior Counsel

PPL Services Corporation

Two North Ninth St.

Allentown, PA 18101

M. Dukes Pepper, Assistant Counsel

Pennsylvania Dept. of Environmental 

Protection

909 Elmerton Ave.

Harrisburg, PA 17110

Sarah G. Novosel, ESQ, 

Senior VP and Managing Counsel

Calpine Corporation

875 15th Street, NW, Suite 700

Washington, DC 20005

Michael R Helfrich, 

Lower Susquehanna Riverkeeper

324 W Market St

York, PA 17401

John C. Seebach, Director, 

Hydropower Reform

American Rivers

1101 14th Street NW, Suite 1400

Washington, DC 20005

James Spontak, Program Manager

Pennsylvania Dept. of Environmental 

Protection

South Central Regional Office

909 Elmerton Avenue

Harrisburg, PA 17110

Brian J. McManus, ESQ 

Jones, Day Reavis & Pogue

1050 Thomas Jefferson Street, NW

Washington, DC 20007

Thomas W. Beauduy, Deputy Director

Susquehanna River Basin Commission

4423 North Front Street

Harrisburg, PA 17102
Michael Brent Hare, Counsel

Maryland Energy Administration

60 West Street, Suite 300

Annapolis, MD 21401

Christine T Lewis-Coker, Hydraulic Engineer

U.S. Army Corps of Eng., Philadelphia Dist.

USACE, Wanamaker Building

100 Penn Square East

Philadelphia, PA 19107

Andrew Tittler, Attorney-Advisor

U.S. Department of Interior

One Gateway Center

Suite 612

Newton, MA 02458

James E Hooper, President, M-DTS

Mason-Dixon Trail System

309 Bank Hill Rd

Wrightsville, PA 17368

Michael Hoover, Senior Regulator Specialist

Devine Tarbell & Associates, Inc.

41 Liberty Hill Road Bldg 1

Henniker, NH 03242

Robert Steelman, 

3529 Greenspring Rd

Havre de Grace, MD 21078

Charles A. Patrizia, Partner

Paul Hastings Janofsky & Walker LLP

701 Pennsylvania Ave., NW

Washington, DC 20004

Harford Land Trust, 

P.O. Box 385

Churchville, MD 21028

Peter Dunbar, 

Maryland Department of Natural Resources

Tawes State Ofc Bldg - B3

Annapolis, MD 21401

Juan Kimble, P.E., 

Safe Harbor Water Power Corporation

1 Powerhouse Rd

Conestoga, PA 17516

Brent A Bolea, Assistant Attorney General

Maryland Office of the Attorney General

60 West Street, Suite 300

Annapolis, MD 21401

County Clerk, 

County of York

100 W Market Street

York, PA 17401

Al Ryan

Exelon Business Services Company

2301 Market

Philadelphia, PA 19103

County Clerk, 

County of Lancaster

50 North Duke Street

PO Box 83480

Lancaster, PA 17608

Colleen E Hicks, Manager

Exelon Corporation

300 Exelon Way

Kennett Square, PA 19348

County Clerk, 

Count of Harford

212 South Bond Street

Bel Air, MD 21014

Executive Director, 

Delaware River Basin Commission

PO Box 7360

25 State Police Rd

West Trenton, NJ 08628

Lower Chanceford Township

4120 Delta Road

Airville, PA 17302

U.S. Coast Guard

MSO PHILADELPHIA

1 Washington Ave

Philadelphia, PA 19147

Peach Bottom Township

545 Broad Street, Extended

Delta, PA 17314
Pennsylvania Fish & Boat Commission

450 Robinson Ln

Bellefonte, PA 16823

Martic Township

370 Steinman Farm Road

Pequea, PA 17565

West Virginia Dept. of Education & Arts

Division of Culture & History

Capitol Complex

Charleston, WV 25305

Drumore Township

1675 Furniss Rd

Drumore, PA 17518

Commanding Officer, 

U.S. Coast Guard

MSO Buffalo

1 Fuhrmann Blvd

Buffalo, NY 14203

Fulton Township

777 Nottingham Road

Peach Bottom, PA 17563

Director

U.S. Fish & Wildlife Service

PO Box: 67000

Harrisburg, PA 17106

City Clerk, 

City of Havre de Grace

711 Pennington Avenue

Havre de Grace, MD 21078

Ryan Smith, V. President

58 Commerce Rd

Stamford, CT 06902

Borough of Oxford

401 Market Street

Oxford, PA 19363

Ben L Cardin, Senator

U.S. Senate

509 Hart Senate Office Bldg

Washington, DC 20510

Town Clerk, 

Town of Bel Air

39 Hickory Avenue

Bel Air, MD 21014

U.S. Coast Guard

MSO Baltimore

2401 Hawkins Point Rd Bldg 70

Baltimore, MD 21226

City Clerk, 

City of Aberdeen

60 North Parke Street

Aberdeen, MD 21001

Field Manager

U.S. Bureau of Land Management

626 E Wisconsin Ave Ste 200

Milwaukee, WI 53202

Kerry A. Abrams, Mayor

Town of Port Deposit

64 S. Main Street

Port Deposit, MD 21904

Project Manager - Hydro, 

U.S. Army Corps of Engs, Pittsburgh District

2200 W. S. Moorhead Federal Bldg

1000 Liberty Ave

Pittsburgh, PA 15222

Dutch Ruppersberger, Congressman

2453 Rayburn House Office Building

Washington, DC 20515

Attorney General

Pennsylvania Office of Attorney General

16tn Floor

Strawberry Square

Harrisburg, PA 17120

Director, 

Maryland Department of the Environment

1800 Washington Blvd

Baltimore, MD 21230
Director

University of Maryland

Center for Environ. & Estuaring Studies

Cambridge, MD 21613

Monica E Marcum, President

Broad Creek Civic Association

9211 Hines Road

Baltimore, MD 21234

Barbara A Mikulski, Honorable

U.S. Senate

503 Hart Senate Office Building

Washington, DC 20510

Joseph R Pitts, Congressman

420 Cannon House Office Building

Washington, DC 20515

Section Chief, 

U.S. Environmental Protection Agency

Region III

1650 Arch St

Philadelphia, PA 19103

Jan Nethen, 

Conowingo Lake Caretakers

PO Box 5869

Darlington, MD 21034

Pennsylvania Dept. of Environmental 

Protection

Southwest Regional Office

400 Waterfront Dr

Pittsburgh, PA 15222

Ken Sommer, 

PO Box 560811

Miami, FL 33256

Michael J Connolly, 

GPU Service, Inc.

300 Madison Ave Fl 3

PO Box 1911

Morristown, NJ 07962

Hoss HL Liaghat, 

Pennsylvania Dept. of Environmental 

Protection

400 Market street

Harrisburg, PA 17105

Pennsylvania Game Commission

2001 Elmerton Ave

Harrisburg, PA 17110

Leo Wallace, ESQ, Attorney

Malone and Neubaum

42 South Duke Street

York, PA 17363

U.S. Fish & Wildlife Service

Chesapeake Bay Field Office

177 Admiral Cochrane Dr

Annapolis, MD 21401

Andrew D. Dehoff, Executive Director

Susquehanna River Basin Commission

4423 North Front Street

Harrisburg, PA 17110

Scott L Guibord, 

GPU Service, Inc.

300 Madison Ave

PO Box 1911

Morristown, NJ 07962

Dawn and Glenn Linton, 

Conowingo Hydro Project

115 Vineyard Drive

Port Deposit, MD 21904

FERC Contact

Upper Chesapeake Watershed Assoc.

13801 York Rd, Apt P12

Cockeysville, NY 21030

PA Dept., Div of Planning & Conservation

PO Box 8467

Harrisburg, PA 17105

Dennis T Guise, 

2313 Forest Hills Dr

Harrisburg, PA 17112

Candice Castaneda, Associate

Paul Hastings LLP

875 15th Street, NW

Washington, DC 20005
Director

Pennsylvania Dept. of Conserv./Nat. Res.

Bureau of Forestry

PO Box 8767

Harrisburg, PA 17105

Stuart Widom, Director, Gov and Reg Affairs

Calpine

500 Delaware Ave, Suite 600

Wilmington, DE 19801

Bonita C Hoke, Director

Pennsylvania Fed. of Sportsmens Clubs

2426 N 2nd St

Harrisburg, PA 17110

Kathleen Barron, 

Exelon Corporation

101 Constitution Ave., NW

Washington, DC 20005

Peco/Energy One

2301 Market St

PO Box 8699

Philadelphia, PA 19101

Robert Gallagher, 

West/Rhode Riverkeeper, Inc

4800 Atwell Road #6

Shady Side, MD 20764

Pennsylvania Department of Agriculture

2301 N Cameron St

Harrisburg, PA 17110

Wayne Melnick, ESQ, Assistant Counsel

Pennsylvania Fish and Boat Commission

PA Fish and Boat Commission

1601 Elmerton Avenue

Harrisburg, PA 17110

Pennsylvania Dept. of Environmental 

Protection

Office Of Pollution Prevention & Compl.

PO Box 8772

Harrisburg, PA 17105

Donald Capecci, 

PPL Holtwood, LLC

Two North Ninth Street

Allentown, PA 18101

Governor

Pennsylvania Office of the Governor

225 Main Capitol

Harrisburg, PA 17120

Elizabeth M Fain, Paralegal

Calpine Corporation

875 15th ST NW, Suite 700

Washington, DC 20005

County of York

York County Courthouse

28 E Market St

York, PA 17401

Nicholas T Niiro, Administrator/Attorney

Water and Power Law Group PC

2140 Shattuck Avenue, Suite 801

Berkeley, CA 94704

Governor

Maryland Office of the Governor

State House

Annapolis, MD 21401

Matthew D. Walderon, Federal Consist. 

Coord.

Pennsylvania Dept, Interstate Waters Office

400 Market St

PO Box 8465

Harrisburg, PA 17101

Maryland Geological Survey

2300 Saint Paul St

Baltimore, MD 21218

Joel Dunn, Executive Director

716 Giddings Ave, Ste 42

Annapolis, MD 21401

Pennsylvania Wildlife Federation

PA Federation of Sportsmen's Clubs, Inc.

2426 N 2nd St

Harrisburg, PA 17110

Kimberly Ognisty, 

Winston & Strawn LLP

1700 K Street, N.W.

Washington, DC 20006
County of Dauphin

Board of County Commissioners

Front & Market Streets

Harrisburg, PA 17101

Jennifer C Chavez, 

1625 Massachusetts Ave NW, Suite 702

Washington, DC 20036

U.S. Fish & Wildlife Service

U.S. Department of the Interior

315 S Allen St Ste 322

State College, PA 16801

Seth L Johnson, Associate Attorney

Earthjustice

1625 Massachusetts Ave., NW, Ste. 702

Washington, DC 20036

Glenn R Meloy, 

U.S. Army Corps of Engineers

North Pacific Division

PO Box 2870

Portland, OR 97208

Jefferson L Blomquist, Attorney

36 S. Charles Street

Twelfth Floor

Baltimore, MD 21201

U.S. Army Corps of Engineers

550 Main Street

Cincinnati, OH 45202

Paul W. Smail, ESQ, Staff Litigation 

Attorney

Chesapeake Bay Foundation

6 Herndon Avenue

Annapolis, MD 21403

M Brent Hare, Atty. Gen.

Maryland Department of Natural Resources

Tawes State Office Building, C-4

580 Taylor Ave

Annapolis, MD 21401

Jon Mueller, Vice President for Litigation

Chesapeake Bay Foundation

6 Herndon Ave

Annapolis, MD 21403

Maryland Public Service Commission

6 St. Paul Centre, 16th Floor

Baltimore, MD 21202

Anna L Wolgast, Executive Director

400 South Cross Street, Suite 2

Chestertown, MD 21620

R. Timothy Weston, 

K&L Gates LLP

17 N 2nd St Fl 18

Harrisburg, PA 17101

Thelma M Grumbein, Residence

1864 Rivervue Drive, North

Drumore, PA 17518

Pennsylvania Dept. of Environmental 

Protection

Bureau of Policy Communication

PO Box 2063

Harrisburg, PA 17105

George Jugovic, JR, 

200 Second Avenue, Suite 200

Pittsburgh, PA 15222

David David, 

York Haven Power Company LLC

York Haven Hydro Plant

Locust St. & Hydro Park Drive

PO Box 67

York Haven, PA 17370

Jill Burke, President 

Cecil Land Use Assoc

PO Box 215

Colora, MD 21917
Regional Director

NOAA National Marine Fisheries Service

Northeast Regional Office-DOC/NOAA

55 Great Republic Dr

Gloucester, MA 01930

Joseph J Heath, 

512 Jamesville Avenue

Syracuse, NY 13210

Regional Director

U.S. Fish & Wildlife Service

300 Westgate Center Dr

Northeast Regional Office

Hadley, MA 01035

Honorable George W Gekas, 

U.S. House of Representatives

Washington, DC 20515

Executive Director

Historical & Museum Commission

300 North St

Harrisburg, PA 17120

Becca Smith, 

Bracewell & Giuliani LLP

2000 K Street NW, Suite 500

Washington, DC 20006

Office of the Solicitor, 

U.S. Bureau of Indian Affairs

1849 C Street, NW, MS 6557

Washington, DC 20240

Stuart S Elstein, Associate

Bracewell & Giuliani LLP

2000 K Street, NW, Suite 500

Washington, DC 20006

Andrew C Zemba, 

Pennsylvania Dept. of Environmental 

Protection

400 Market St Fl 2

PO Box 2063

Harrisburg, PA 17105

Executive Director, 

Maryland Historic Preservation Officer

100 Community Pl

Crownsville, MD 21032

John Garver, 

Tri-County Boat Club

Middletown, PA 17057
APPENDIX A

DRAFT LICENSE ARTICLES

YORK HAVEN HYDROELECTRIC PROJECT 
This page intentionally left blank.
Appendix A

Draft License Articles

York Haven Hydroelectric Project 

Article 201. Administrative Annual Charges. The licensee shall pay the United 

States annual charges, effective the first day of the month in which the license is issued, 

and as determined in accordance with provisions of the Commission's regulations in 

effect from time to time, for the purposes of: 

(a) reimbursing the United States for the cost of administration of Part I of the 

Federal Power Act. The authorized installed capacity for that purpose is 

19.62 megawatts. 

Article 202. Exhibit F Drawings. Within 45 days of the date of issuance of this 

license, as directed below, the licensee shall file the approved exhibit drawings in 

electronic file format on CD disks.

Digital images of the approved exhibit drawings shall be prepared in electronic 

format. Prior to preparing each digital image, the FERC Project-Drawing Number 

(i.e., P-1888-1001 through P-1888-###) shall be shown in the margin below the title 

block of the approved drawing. The licensee shall file two sets of exhibit drawings in 

electronic format on CD disks with the Secretary of the Commission, ATTN: 

OEP/DHAC. Exhibit F drawings must be identified as Critical Energy Infrastructure 

Information (CEII) material under 18 CFR §388.113(c). Each drawing must be a 

separate electronic file, and the file name shall include: FERC Project-Drawing Number, 

FERC Exhibit, Drawing Title, date of this License, and file extension in the following 

format [P-1888-####, F-1, Description, MM-DD-YYYY.TIF]. All digital images of the 

exhibit drawings shall meet the following format specification:

IMAGERY - black & white raster file 

FILE TYPE – Tagged Image File Format, (TIFF) CCITT Group 4 

RESOLUTION – 300 dpi desired, (200 dpi min)

DRAWING SIZE FORMAT – 24” x 36” (min), 28” x 40” (max)

FILE SIZE – less than 1 MB desired

Article 203. Exhibit G Drawings. Within 90 days of the effective date of the 

license, the licensee shall file, for Commission approval, revised Exhibit G drawings 

enclosing within the project boundary all principal project works necessary for operation 

and maintenance of the project, including all of the lands encompassing the East Shore 
Boat Launch and Canal Lock recreation area. The Exhibit G drawings must comply with 

sections 4.39 and 4.41 of the Commission’s regulations.

Article 204. Amortization Reserve. Pursuant to section 10(d) of the Federal 

Power Act, a specified reasonable rate of return upon the net investment in the project 

shall be used for determining surplus earnings of the project for the establishment and 

maintenance of amortization reserves. The licensee shall set aside in a project 

amortization reserve account at the end of each fiscal year one-half of the project surplus 

earnings, if any, in excess of the specified rate of return per annum on the net investment. 

To the extent that there is a deficiency of project earnings below the specified rate of 

return per annum for any fiscal year, the licensee shall deduct the amount of that 

deficiency from the amount of any surplus earnings subsequently accumulated, until 

absorbed. The licensee shall set aside one-half of the remaining surplus earnings, if any, 

cumulatively computed, in the project amortization reserve account. The licensee shall 

maintain the amounts established in the project amortization reserve account until further 

order of the Commission.

The specified reasonable rate of return used in computing amortization reserves 

shall be calculated annually based on current capital ratios developed from an average of 

13 monthly balances of amounts properly included in the licensee's long-term debt and 

proprietary capital accounts as listed in the Commission's Uniform System of Accounts. 

The cost rate for such ratios shall be the weighted average cost of long-term debt and 

preferred stock for the year, and the cost of common equity shall be the interest rate on 

10-year government bonds (reported as the Treasury Department's 10-year constant 

maturity series) computed on the monthly average for the year in question plus four 

percentage points (400 basis points).

Article 205. Headwater Benefits. If the licensee's project was directly benefited 

by the construction work of another licensee, a permittee, or the United States on a 

storage reservoir or other headwater improvement during the term of the original license 

(including extensions of that term by annual licenses), and if those headwater benefits 

were not previously assessed and reimbursed to the owner of the headwater 

improvement, the licensee shall reimburse the owner of the headwater improvement for 

those benefits, at such time as they are assessed, in the same manner as for benefits 

received during the term of this new license. The benefits will be assessed in accordance 

with Part 11, Subpart B, of the Commission's regulations.

Article 301. Contract Plans and Specifications. At least 60 days prior to the start 

of any construction, the licensee shall submit one copy of its plans and specifications and 
supporting design document to the Commission’s Division of Dam Safety and 

Inspections (D2SI) – New York Regional Engineer, and two copies to the Commission 

(one of these shall be a courtesy copy to the Director, D2SI). The submittal to the D2SI 

New York Regional Engineer must also include as part of preconstruction requirements: 

a Quality Control and Inspection Program, Temporary Construction Emergency Action 

Plan, and Soil Erosion and Sediment Control Plan. The licensee may not begin 

construction until the D2SI-New York Regional Engineer has reviewed and commented 

on the plans and specifications, determined that all preconstruction requirements have 

been satisfied, and authorized start of construction.

Article 302. Cofferdam and Deep Excavation Construction Drawings. Should 

construction require cofferdams or deep excavations, the licensee shall: (1) review and 

approve the design of contractor-designed cofferdams and deep excavations prior to the 

start of construction; and (2) shall ensure that construction of cofferdams and deep 

excavations is consistent with the approved design. At least 30 days before starting 

construction of any cofferdams or deep excavations, the licensee shall submit one copy to 

the Commission’s Division of Dam Safety and Inspections (D2SI) - New York Regional 

Engineer and two copies to the Commission (one of these copies shall be a courtesy copy 

to the Commission's Director, D2SI), of the approved cofferdam and deep excavation 

construction drawings and specifications, and the letters of approval.

 Article 303. As-built Drawings. Within 90 days of completion of construction of 

the facilities authorized by this license, the licensee shall file for Commission approval, 

revised exhibits A, F, and G, as applicable, to describe and show those project facilities 

as built. A courtesy copy shall be filed with the Commission’s Division of Dam Safety 

and Inspections (D2SI) - New York Regional Engineer, the Director, D2SI, and the 

Director, Division of Hydropower Administration and Compliance.

Article 304. Project Modification Resulting From Environmental Requirements. 

Any permanent or temporary modification which may affect the project works or 

operations shall be coordinated with the Commission’s Division Dam Safety and 

Inspections (D2SI) - New York Regional Engineer at the beginning of the planning and 

design phase. This includes those modifications resulting from license environmental 

requirements. This schedule is to allow sufficient review time for the Commission to 

insure that the proposed work does not adversely affect the project works, dam safety or 

project operation.

Article 401. Erosion and Sediment Control Plan. Within 6 months of license 

issuance, the licensee shall file, for Commission approval, an erosion and sediment 
control plan for implementation during construction of the nature-like fishway. The plan 

shall be based on actual-site geological, soil, and groundwater conditions and on project 

design, and shall include, at a minimum, the following:

(1) A detailed description of actual site conditions;

(2) Measures proposed to control erosion, to prevent slope instability, and to 

minimize the quantity of sediment resulting from fishway construction;

(3) Detailed descriptions, functional design drawings, and specific topographic 

locations of control measures; and

(4) A specific implementation schedule of control measures and monitoring and 

maintenance of proposed control measures during construction. 

The plan shall be developed after consultation with the Pennsylvania Department 

of Environmental Protection; the Pennsylvania Fish and Boat Commission; and the U.S. 

Fish and Wildlife Service. The licensee shall include with the plan an implementation 

schedule, documentation of consultation, copies of recommendations on the completed 

plan after it has been prepared and provided to the entities above, and specific 

descriptions of how the entities’ comments are accommodated by the plan. The licensee 

shall provide a minimum of 30 days for the entities to comment and to make 

recommendations before filing the plan with the Commission. If the licensee does not 

adopt a recommendation, the filing shall include the licensee’s reasons, based on projectspecific reasons.

The Commission reserves the right to require changes to the plan. Implementation 

of the plan shall not begin until the licensee is notified by the Commission that the plan is 

approved. Upon Commission approval, the licensee shall implement the plan, including 

any changes required by the Commission.

Article 402. Minimum Flows. The licensee shall provide a year-round, 

continuous, minimum flow from the project of 1,000 cubic feet per second (cfs) and an 

average daily minimum flow of 2,500 cfs, or inflow, whichever is less, for the protection 

of aquatic habitat in the Susquehanna River downstream of the project.

Minimum flow releases may be temporarily modified if required by operating 

emergencies beyond the control of the licensee, and for short periods upon mutual 

agreement among the licensee and the Pennsylvania Department of Environmental 

Protection. If minimum flows are so modified, the licensee shall notify the Commission, 

in writing, as soon as possible, but no later than 10 days after each such incident. 
Article 403. Run-of-River Operations. When inflow to the project is less than 

3,000 cubic feet per second, the licensee shall operate the York Haven Project in an 

instantaneous run-of-river mode for the protection of aquatic resources in the 

Susquehanna River, without deliberate impoundment drawdown or storage for purposes 

of generating electricity in particular time periods. 

Run-of-river operation may be temporarily modified if required by operating 

emergencies beyond the control of the licensee, and for short periods upon mutual 

agreement between the licensee and the Pennsylvania Department of Environmental 

Protection. If run-of-river operation is so modified, the licensee shall notify the 

Commission, in writing, as soon as possible, but no later than 10 days after each such 

incident. 

Article 404. Debris Management. The licensee shall implement debris 

management as detailed in section 9.b. of the Settlement Agreement to ensure debris does 

not pose long-term hazards to people and project operation. Prior to passing debris 

downstream of the project, the licensee shall provide notice to PPL’s Brunner Island 

steam plant to allow PPL the opportunity to plan or prepare for any inconvenience from 

passing debris. 

Article 405. Reservation of Authority to Prescribe Fishways. Authority is 

reserved to the Commission to require the licensee to construct, operate, and maintain, or 

provide for the construction, operation, and maintenance of, such fishways as may be 

prescribed by the Secretary of the Interior pursuant to section 18 of the Federal Power 

Act.

Article 406. Pre-Construction Environmental Studies for the Nature-Like 

Fishway. Six months prior to the commencement of construction of the nature-like 

fishway required by the U.S. Department of Interior’s fishway prescription (Appendix 

D), the licensee shall develop and conduct the following studies in the area to be 

disturbed by construction of the nature-like fishway: (1) vegetation cover-type mapping, 

(2) wetlands delineations, (3) invasive species surveys, (4) rare species surveys, (5) a bog 

turtle habitat assessment, and (6) a bald eagle survey.

The licensee shall prepare study plans for each study after consultation with the 

Pennsylvania Department of Environmental Protection, Pennsylvania Game Commission; 

Pennsylvania Fish and Boat Commission, and the U.S. Fish and Wildlife Service. The 

licensee shall include with each study plan an implementation schedule, documentation 

of consultation, copies of recommendations on the completed plans after the study plans 
have been prepared and provided to the entities above, and specific descriptions of how 

the entities’ comments are accommodated by the plan. The licensee shall provide a 

minimum of 30 days for the entities to comment and to make recommendations before 

implementing the study plans. If the licensee does not adopt a recommendation, the 

filing shall include the licensee’s reasons, based on project-specific reasons. The study 

plans also shall include a provision for filing the completed studies with the Commission 

prior to commencement of construction. 

The Commission reserves the right to require changes to the study plans. The 

licensee shall not begin conducting the studies until notified by the Commission that the 

study plans are approved. Upon Commission approval, the licensee shall conduct the 

studies, including any changes required by the Commission.

Article 407. Recreation Management Plan. Within 6 months of license issuance, 

the licensee shall file, for Commission approval, a recreation management plan that 

details measures to ensure the recreation facilities and sites are managed to meet use and 

demand over the term of the license. The plan shall include a facility inventory with 

ownership and management responsibilities for each site, as well as measures to provide 

for periodic monitoring, to ensure the recreation facilities and sites are managed to meet 

use and demand over the term of the license, and a provision to address public safety 

during the construction of the nature-like fishway. In addition, plan shall detail how the 

licensee will continue the licensing program for approximately 300 recreational lots

within the project boundary. The plan also shall include details on how the licensee will 

implement revisions to the program that allow for the termination of permits and removal 

of lots from the program if structures are abandoned by the lessee, or when existing 

structures become damaged and are not replaced by conforming structures. The 

recreation management plan shall be updated every 12 years in concert with every other 

Form 80 reporting period. The licensee shall also consult with the Pennsylvania Fish and 

Boat Commission, the Pennsylvania Department of Environmental Protection, the 

Pennsylvania Department of Conservation and Natural Resources, and the Susquehanna 

River Basin Commission about recreation management and strategies every 10 years 

after the effective date of the new license. 

The plan shall be developed after consultation with resource agencies, counties, 

and other interested stakeholders, including the Pennsylvania Fish and Boat Commission 

and Pennsylvania Department of Conservation and Natural Resources. The licensee shall 

include with the plan an implementation schedule, documentation of consultation, copies 

of recommendations on the completed plan after it has been prepared and provided to the 

entities above, and specific descriptions of how the entities’ comments are 
accommodated by the plan. The licensee shall provide a minimum of 30 days for the 

entities to comment and to make recommendations before filing the plan with the 

Commission. If the licensee does not adopt a recommendation, the filing shall include 

the licensee’s reasons, based on project-specific reasons.

The licensee shall continue to operate and maintain the following existing 

facilities for the term of the license: (1) York Haven Power Plant Recreation Area; 

(2) Battery Island Picnic Area; (3) Goodling Island Picnic Area; (4) Shelley Island 

Recreation Area; (5) Goosehorn Island Picnic Area; (6) East Shore Boat Launch; and 

(7) East Shore Canal Lock. If the licensee proposes changes to the existing facilities, the 

licensee shall file the changes with the Commission for approval. 

The Commission reserves the right to require changes to the plan. Implementation 

of the plan shall not begin until the licensee is notified by the Commission that the plan is 

approved. Upon Commission approval, the licensee shall implement the plan, including 

any changes required by the Commission.

Article 408. Shoreline Management Plan. Within one year of license issuance, 

the licensee shall file, for Commission approval, a shoreline management plan. The plan 

shall be developed in accordance with the Commission’s Guidance on Shoreline 

Management Planning and Hydroelectric Projects and include policies to ensure that the 

shorelines are managed for the scenic, recreational, and environmental values for the 

duration of the license term, including but not limited to (1) a summary of the purpose, 

goals and objectives of the plan; (2) a description of the shoreline use classifications, 

which identifies allowable and prohibited uses for existing and future use of the 

shoreline; (3) a shoreline permitting program; (4) a monitoring and enforcement program; 

and (5) a provision to update the plan every 10 years.

As part of the SMP, the licensee shall continue the licensing program for 

approximately 300 recreational lots at Cly Shore, Shelley Island, and Beshore Island. 

The licensee shall implement revisions in the licensing program to allow the termination 

of permits and removal from the licensing program of existing recreational lots that are 

abandoned by the lessee, or when existing structures become damaged and are not 

replaced by structures conforming to all applicable federal, state, and local regulations.

The plan shall be developed in accordance with the Commission’s Guidelines for 

Shoreline Management Planning at Hydropower Projects dated July 2012. The plan 

shall be developed in consultation with the Pennsylvania Fish and Boat Commission, 

Pennsylvania Department of Conservation and Natural Resources, and the Pennsylvania 
Department of Environmental Protection. The licensee shall include with the plan an 

implementation schedule, documentation of consultation, copies of recommendations on 

the completed plan after it has been prepared and provided to the entities above, and 

specific descriptions of how the entities’ comments are accommodated by the plan. The 

licensee shall provide a minimum of 30 days for the entities to comment and to make 

recommendations before filing the plan with the Commission. If the licensee does not 

adopt a recommendation, the filing shall include the licensee’s reasons, based on projectspecific reasons.

The Commission reserves the right to require changes to the plan. Implementation 

of the plan shall not begin until the licensee is notified by the Commission that the plan is 

approved. Upon Commission approval, the licensee shall implement the plan, including 

any changes required by the Commission.

Article 409. Programmatic Agreement and Historic Properties Management 

Plan. Upon license issuance, the licensee shall implement the Programmatic Agreement 

Between the Federal Energy Regulatory Commission and the Pennsylvania Historic 

Preservation Officer for Managing Historic Properties that May be Affected by Issuing a 

New License to York Haven Power Company, LLC, for the Continued Operation of the 

York Haven Project in York, Dauphin, and Lancaster counties, Pennsylvania (FERC 

No. 1888-030), executed on ____________, and including but not limited to the Historic 

Properties Management Plan (HPMP) for the project. Pursuant to the requirement of this 

Programmatic Agreement, the license shall file, for Commission approval, a revised 

HPMP within six months of issuance of this order. The revised HPMP shall be based on 

the draft HPMP filed with the Commission on December 28, 2012, and include the 

following:

(a) a requirement to request landowner access to evaluate any affected sites 

located on private property;

(b) a plan and schedule to evaluate archaeological sites on fee lands for their 

National Register eligibility, which would ensure that any effects on sites owned 

by York Haven Power are fully considered in accordance with section 106; and

(c) a provision to include two additional sites (36YO300, 36YO334) in the 

monitoring schedule, or clarification regarding why they were excluded. 

The Commission reserves the authority to require changes to the HPMP at any 

time during the term of the license. If the Programmatic Agreement is terminated prior to 

Commission approval of the HPMP, the licensee shall obtain approval from the 
Commission and the Pennsylvania State Historic Preservation Officers, before engaging 

in any ground-disturbing activities or taking any other action that may affect any historic 

properties within the project's area of potential effects.

Article 410. Use and Occupancy. (a) In accordance with the provisions of this 

article, the licensee shall have the authority to grant permission for certain types of use 

and occupancy of project lands and waters and to convey certain interests in project lands 

and waters for certain types of use and occupancy, without prior Commission approval. 

The licensee may exercise the authority only if the proposed use and occupancy is 

consistent with the purposes of protecting and enhancing the scenic, recreational, and 

other environmental values of the project. For those purposes, the licensee shall also 

have continuing responsibility to supervise and control the use and occupancies for which 

it grants permission, and to monitor the use of, and ensure compliance with the covenants 

of the instrument of conveyance for, any interests that it has conveyed, under this article. 

If a permitted use and occupancy violates any condition of this article or any other 

condition imposed by the licensee for protection and enhancement of the project's scenic, 

recreational, or other environmental values, or if a covenant of a conveyance made under 

the authority of this article is violated, the licensee shall take any lawful action necessary 

to correct the violation. For a permitted use or occupancy, that action includes, if 

necessary, canceling the permission to use and occupy the project lands and waters and 

requiring the removal of any non-complying structures and facilities.

(b) The type of use and occupancy of project lands and waters for which the 

licensee may grant permission without prior Commission approval are: (1) landscape 

plantings; (2) non-commercial piers, landings, boat docks, or similar structures and 

facilities that can accommodate no more than 10 water craft at a time and where said 

facility is intended to serve single-family type dwellings; (3) embankments, bulkheads, 

retaining walls, or similar structures for erosion control to protect the existing shoreline; 

and (4) food plots and other wildlife enhancement. To the extent feasible and desirable to 

protect and enhance the project's scenic, recreational, and other environmental values, the 

licensee shall require multiple use and occupancy of facilities for access to project lands 

or waters. The licensee shall also ensure, to the satisfaction of the Commission's 

authorized representative, that the use and occupancies for which it grants permission are 

maintained in good repair and comply with applicable state and local health and safety 

requirements. Before granting permission for construction of bulkheads or retaining 

walls, the licensee shall: (1) inspect the site of the proposed construction, (2) consider 

whether the planting of vegetation or the use of riprap would be adequate to control 

erosion at the site, and (3) determine that the proposed construction is needed and would 
not change the basic contour of the impoundment shoreline. To implement this 

paragraph (b), the licensee may, among other things, establish a program for issuing 

permits for the specified types of use and occupancy of project lands and waters, which 

may be subject to the payment of a reasonable fee to cover the licensee's costs of 

administering the permit program. The Commission reserves the right to require the 

licensee to file a description of its standards, guidelines, and procedures for implementing 

this paragraph (b) and to require modification of those standards, guidelines, or 

procedures.

(c) The licensee may convey easements or rights-of-way across, or leases of 

project lands for: (1) replacement, expansion, realignment, or maintenance of bridges or 

roads where all necessary state and federal approvals have been obtained; (2) storm 

drains and water mains; (3) sewers that do not discharge into project waters; (4) minor 

access roads; (5) telephone, gas, and electric utility distribution lines; (6) non-project 

overhead electric transmission lines that do not require erection of support structures 

within the project boundary; (7) submarine, overhead, or underground major telephone 

distribution cables or major electric distribution lines (69-kV or less); and (8) water 

intake or pumping facilities that do not extract more than one million gallons per day 

from a project impoundment. No later than January 31 of each year, the licensee shall 

file three copies of a report briefly describing for each conveyance made under this 

paragraph (c) during the prior calendar year, the type of interest conveyed, the location of 

the lands subject to the conveyance, and the nature of the use for which the interest 

was conveyed. 

(d) The licensee may convey fee title to, easements or rights-of-way across, or 

leases of project lands for: (1) construction of new bridges or roads for which all 

necessary state and federal approvals have been obtained; (2) sewer or effluent lines that 

discharge into project waters, for which all necessary federal and state water quality 

certification or permits have been obtained; (3) other pipelines that cross project lands or 

waters but do not discharge into project waters; (4) non-project overhead electric 

transmission lines that require erection of support structures within the project boundary, 

for which all necessary federal and state approvals have been obtained; (5) private or 

public marinas that can accommodate no more than 10 water craft at a time and are 

located at least one-half mile (measured over project waters) from any other private or 

public marina; (6) recreational development consistent with an approved report on 

recreational resources of an Exhibit E; and (7) other uses, if: (i) the amount of land 

conveyed for a particular use is five acres or less; (ii) all of the land conveyed is located 

at least 75 feet, measured horizontally, from project waters at normal surface elevation; 
and (iii) no more than 50 total acres of project lands for each project development are 

conveyed under this clause (d)(7) in any calendar year. At least 60 days before 

conveying any interest in project lands under this paragraph (d), the licensee must file a 

letter with the Commission, stating its intent to convey the interest and briefly describing 

the type of interest and location of the lands to be conveyed (a marked Exhibit G map 

may be used), the nature of the proposed use, the identity of any federal or state agency 

official consulted, and any federal or state approvals required for the proposed use. 

Unless the Commission's authorized representative, within 45 days from the filing date, 

requires the licensee to file an application for prior approval, the licensee may convey the 

intended interest at the end of that period.

(e) The following additional conditions apply to any intended conveyance under 

paragraph (c) or (d) of this article:

(1) Before conveying the interest, the licensee shall consult with federal and state 

fish and wildlife or recreation agencies, as appropriate, and the State Historic 

Preservation Officer.

(2) Before conveying the interest, the licensee shall determine that the proposed 

use of the lands to be conveyed is not inconsistent with any approved report on 

recreational resources of an Exhibit E; or, if the project does not have an approved report 

on recreational resources, that the lands to be conveyed do not have recreational value.

(3) The instrument of conveyance must include the following covenants running 

with the land: (i) the use of the lands conveyed shall not endanger health, create a 

nuisance, or otherwise be incompatible with overall project recreational use; (ii) the 

grantee shall take all reasonable precautions to ensure that the construction, operation, 

and maintenance of structures or facilities on the conveyed lands will occur in a manner 

that will protect the scenic, recreational, and environmental values of the project; and (iii) 

the grantee shall not unduly restrict public access to project waters.

(4) The Commission reserves the right to require the licensee to take reasonable 

remedial action to correct any violation of the terms and conditions of this article, for the 

protection and enhancement of the project's scenic, recreational, and other 

environmental values.

(f) The conveyance of an interest in project lands under this article does not in 

itself change the project boundaries. The project boundaries may be changed to exclude 

land conveyed under this article only upon approval of revised Exhibit G drawings 

(project boundary maps) reflecting exclusion of that land. Lands conveyed under this 
article will be excluded from the project only upon a determination that the lands are not 

necessary for project purposes, such as operation and maintenance, flowage, recreation, 

public access, protection of environmental resources, and shoreline control, including 

shoreline aesthetic values. Absent extraordinary circumstances, proposals to exclude 

lands conveyed under this article from the project shall be consolidated for consideration 

when revised Exhibit G drawings would be filed for approval for other purposes.

(g) The authority granted to the licensee under this article shall not apply to any 

part of the public lands and reservations of the United States included within the project 

boundary.
APPENDIX B

DRAFT LICENSE ARTICLES

MUDDY RUN PUMPED STORAGE PROJECT 
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Appendix B

Draft License Articles

Muddy Run Pumped Storage Project 

Article 201. Administrative Annual Charges. The licensee shall pay the United 

States annual charges, effective the first day of the month in which the license is issued, 

and as determined in accordance with provisions of the Commission's regulations in 

effect from time to time, for the purposes of: 

(a) reimbursing the United States for the cost of administration of Part I of the 

Federal Power Act. The authorized installed capacity for that purpose is 

800.25-megawatts. 

Article 202. Exhibit Drawings. Within 45 days of the date of issuance of this 

license, as directed below, the licensee shall file the approved exhibit drawings and GIS 

data in electronic file format on CD disks.

(a) Digital images of the approved exhibit drawings shall be prepared in 

electronic format. Prior to preparing each digital image, the FERC Project-Drawing 

Number (i.e., P-2355-1001 through P-2355-###) shall be shown in the margin below the 

title block of the approved drawing. The licensee shall file two separate sets of exhibit 

drawings in electronic format on CD disks with the Secretary of the Commission, 

ATTN: OEP/DHAC. Exhibit F drawings must be segregated from other project exhibits, 

and identified as Critical Energy Infrastructure Information (CEII) material under 

18 CFR §388.113(c). Each drawing must be a separate electronic file, and the file name 

shall include: FERC Project-Drawing Number, FERC Exhibit, Drawing Title, date of this 

License, and file extension in the following format [P-2355-####, G-1, Project Boundary, 

MM-DD-YYYY.TIF]. All digital images of the exhibit drawings shall meet the 

following format specification:

IMAGERY - black & white raster file 

FILE TYPE – Tagged Image File Format, (TIFF) CCITT Group 4 

RESOLUTION – 300 dpi desired, (200 dpi min)

DRAWING SIZE FORMAT – 24” x 36” (min), 28” x 40” (max)

FILE SIZE – less than 1 MB desired

Each Exhibit G drawing that includes the project boundary must contain a 

minimum of three known reference points (i.e., latitude and longitude coordinates, or 

state plane coordinates). The points must be arranged in a triangular format for GIS 
georeferencing the project boundary drawing to the polygon data, and must be based on a 

standard map coordinate system. The spatial reference for the drawing (i.e., map 

projection, map datum, and units of measurement) must be identified on the drawing and 

each reference point must be labeled. In addition, each project boundary drawing must 

be stamped by a registered land surveyor.

(b) The licensee shall file two separate sets of the project boundary GIS data on 

CD disks with the Secretary of the Commission, ATTN: OEP/DHAC. The data shall be 

in a georeferenced electronic file format (such as ArcView shape files, GeoMedia files, 

MapInfo files, or a similar GIS format). The filing shall include both polygon data and 

all reference points shown on the individual project boundary drawings. An electronic 

boundary polygon data file(s) is required for each project development. Depending on 

the electronic file format, the polygon and point data can be included in single files with 

multiple layers. The georeferenced electronic boundary data file must be positionally 

accurate to ±40 feet in order to comply with National Map Accuracy Standards for maps 

at a 1:24,000 scale. The file name(s) shall include: FERC Project Number, data 

description, date of this License, and file extension in the following format [P-2355, 

boundary polygon/or point data, MM-DD-YYYY.SHP]. The data must be accompanied 

by a separate text file describing the spatial reference for the georeferenced data: map 

projection used (i.e., UTM, State Plane, Decimal Degrees, etc.), the map datum (i.e., 

North American 27, North American 83, etc.), and the units of measurement (i.e., feet, 

meters, miles, etc.). The text file name shall include: FERC Project Number, data 

description, date of this License, and file extension in the following format [P-2355, 

project boundary metadata, MM-DD-YYYY.TXT].

Article 203. Amortization Reserve. Pursuant to section 10(d) of the Federal 

Power Act, a specified reasonable rate of return upon the net investment in the project 

shall be used for determining surplus earnings of the project for the establishment and 

maintenance of amortization reserves. The licensee shall set aside in a project 

amortization reserve account at the end of each fiscal year one-half of the project surplus 

earnings, if any, in excess of the specified rate of return per annum on the net investment. 

To the extent that there is a deficiency of project earnings below the specified rate of 

return per annum for any fiscal year, the licensee shall deduct the amount of that 

deficiency from the amount of any surplus earnings subsequently accumulated, until 

absorbed. The licensee shall set aside one-half of the remaining surplus earnings, if any, 

cumulatively computed, in the project amortization reserve account. The licensee shall 

maintain the amounts established in the project amortization reserve account until further 

order of the Commission.
The specified reasonable rate of return used in computing amortization reserves 

shall be calculated annually based on current capital ratios developed from an average of 

13 monthly balances of amounts properly included in the licensee's long-term debt and 

proprietary capital accounts as listed in the Commission's Uniform System of Accounts. 

The cost rate for such ratios shall be the weighted average cost of long-term debt and 

preferred stock for the year, and the cost of common equity shall be the interest rate on 

10-year government bonds (reported as the Treasury Department's 10-year constant 

maturity series) computed on the monthly average for the year in question plus four 

percentage points (400 basis points).

Article 301. Project Modification Resulting From Environmental Requirements. 

Any permanent or temporary modification which may affect the project works or 

operations shall be coordinated with the Commission’s Division Dam Safety and 

Inspections (D2SI) - New York Regional Engineer at the beginning of the planning and 

design phase. This includes those modifications resulting from license environmental 

requirements. This schedule is to allow sufficient review time for the Commission to 

insure that the proposed work does not adversely affect the project works, dam safety or 

project operation

Article 401. Reservation of Authority to Prescribe Fishways. Authority is 

reserved to the Commission to require the licensee to construct, operate, and maintain, or 

provide for the construction, operation, and maintenance of, such fishways as may be 

prescribed by the Secretary of the Interior and/or Commerce pursuant to section 18 of the 

Federal Power Act.

Article 402. Bald Eagle Management Plan. The Bald Eagle Management Plan

(BEMP), filed on August 29, 2012, is approved with the following modification: before 

any ground disturbance work begins within the project boundary, the licensee shall visit 

the U.S. Fish and Wildlife Service’s (FWS) Chesapeake Bay Field Office and 

Pennsylvania Field Office websites and comply with current bald eagle management 

guidelines. If there are updated guidelines, the licensee shall revise the BEMP to 

incorporate any new guidelines issued by the FWS during the term of the license and 

provide the revised BEMP to the Commission for approval. 

The Bald Eagle Management Plan, as modified, shall be made part of this license, 

and may not be amended without prior Commission approval. Upon license issuance, the 

licensee shall implement the plan according to the schedule included in the plan. The 

Commission reserves the right to require any additional changes to the plan.
Article 403. Bog Turtle Management Plan. The Bog Turtle Management Plan,

filed on August 29, 2012, is approved with the following modification: before any 

ground disturbance work begins within the project boundary, the licensee shall visit the 

U.S. Fish and Wildlife Service’s Chesapeake Bay Field Office and Pennsylvania Field 

Office websites and comply with current bog turtle management guidelines. If there are 

updated guidelines, the licensee shall revise the BEMP to incorporate any new guidelines 

issued by the FWS during the term of the license and provide the revised BEMP to the 

Commission for approval.

The Bog Turtle Management Plan shall be made part of this license, and may not 

be amended without prior Commission approval. Upon license issuance, the licensee

shall implement the plan according to the schedule included in the plan. The 

Commission reserves the right to require any additional changes to the plan.

Article 404. Recreation Management Plan. The Recreation Management Plan,

filed on August 29, 2012, is approved with the following modification: conduct a 

recreation use study every 12 years throughout the license term, consistent with every 

other FERC Form 80 reporting period deadline, to ensure the proposed plans are current 

and the sites are meeting the demand.

Each update to the plan shall be developed in consultation with the U.S. Fish and 

Wildlife Service, the Pennsylvania Department of Conservation and Natural Resources,

and the Maryland Department of the Environment. The licensee shall include with the

updated plans an implementation schedule, documentation of consultation, copies of 

recommendations on the completed plan after it has been prepared and provided to the 

entities above, and specific descriptions of how the entities’ comments are 

accommodated by the plan. The licensee shall provide a minimum of 30 days for the 

entities to comment and to make recommendations before filing the updated plans with 

the Commission. If the licensee does not adopt a recommendation, the filing shall 

include the licensee’s reasons, based on project-specific reasons.

The licensee shall continue to operate and maintain the following existing 

facilities for the term of the license: Muddy Run Park and Campground, Wissler’s Run 

Park, and Muddy Run Wildlife Management Area. If the licensee proposes changes to 

the existing facilities, the licensee shall file the changes with the Commission for 

approval.

The Recreation Management Plan, as modified, shall be made part of this license, 

and may not be amended without prior Commission approval. Upon license issuance, the 
licensee shall implement the plan according to the schedule included in the plan. The 

Commission reserves the right to require any additional changes to the plan.

Article 405. Shoreline Management Plan. The Shoreline Management Plan, filed 

on August 29, 2012, is approved with the following modification: the plan shall be 

updated every 10 years. 

Each updated plan shall be developed in consultation with the U.S. Fish and 

Wildlife Service, the Pennsylvania Department of Conservation and Natural Resources,

and the Maryland Department of the Environment. The licensee shall include with the 

updated plans an implementation schedule, documentation of consultation, copies of 

recommendations on the completed plan after it has been prepared and provided to the 

entities above, and specific descriptions of how the entities’ comments are 

accommodated by the plan. The licensee shall provide a minimum of 30 days for the 

entities to comment and to make recommendations before filing the updated plans with 

the Commission. If the licensee does not adopt a recommendation, the filing shall 

include the licensee’s reasons, based on project-specific reasons.

The Shoreline Management Plan, as modified, shall be made part of this license, 

and may not be amended without prior Commission approval. Upon license issuance, the 

licensee shall implement the plan according to the schedule included in the plan. The 

Commission reserves the right to require any additional changes to the plan.

Article 406. Programmatic Agreement and Historic Properties Management 

Plan. Upon license issuance, the licensee shall implement the Programmatic Agreement 

Between the Federal Energy Regulatory Commission and the Pennsylvania Historic 

Preservation Officer for Managing Historic Properties that May be Affected by Issuing a 

New License to Exelon Generation Company, LLC, for the Continued Operation of the 

Muddy Run Pumped Storage Project in Lancaster and York counties, Pennsylvania, 

(FERC No. 2355-018), executed on ____________, and including but not limited to the 

Historic Properties Management Plan (HPMP) for the project. Pursuant to the 

requirement of this Programmatic Agreement, the license shall file, for Commission 

approval, an HPMP, within one year of issuance of this order. 

The plan shall include, at a minimum: 

(a) a detailed discussion of the three sites identified during Phase IA cultural 

resources surveys (36LA67, 36LA103, 36LA368) and two additional sites located 

outside of the project boundary (36LA70, 36LA47); 
(b) requirements for National Register of Historic Places (National Register) 

evaluation of affected sites in consultation with the Pennsylvania State Historic 

Preservation Officer (SHPO); 

(c) requirements for formal National Register evaluation of the Muddy Run 

Pumped Storage Project; and 

(d) documentation of tribal consultation.

The Commission reserves the authority to require changes to the HPMP at any 

time during the term of the license. If the Programmatic Agreement is terminated prior to 

Commission approval of the HPMP, the licensee shall obtain approval from the 

Commission and the Pennsylvania SHPO, before engaging in any ground-disturbing 

activities or taking any other action that may affect any historic properties within the 

project's area of potential effects.

Article 407. Use and Occupancy. (a) In accordance with the provisions of this 

article, the licensee shall have the authority to grant permission for certain types of use 

and occupancy of project lands and waters and to convey certain interests in project lands 

and waters for certain types of use and occupancy, without prior Commission approval. 

The licensee may exercise the authority only if the proposed use and occupancy is 

consistent with the purposes of protecting and enhancing the scenic, recreational, and 

other environmental values of the project. For those purposes, the licensee shall also 

have continuing responsibility to supervise and control the use and occupancies for which 

it grants permission, and to monitor the use of, and ensure compliance with the covenants 

of the instrument of conveyance for, any interests that it has conveyed, under this article. 

If a permitted use and occupancy violates any condition of this article or any other 

condition imposed by the licensee for protection and enhancement of the project's scenic, 

recreational, or other environmental values, or if a covenant of a conveyance made under 

the authority of this article is violated, the licensee shall take any lawful action necessary 

to correct the violation. For a permitted use or occupancy, that action includes, if 

necessary, canceling the permission to use and occupy the project lands and waters and 

requiring the removal of any non-complying structures and facilities.

(b) The type of use and occupancy of project lands and waters for which the 

licensee may grant permission without prior Commission approval are: (1) landscape 

plantings; (2) non-commercial piers, landings, boat docks, or similar structures and 

facilities that can accommodate no more than 10 water craft at a time and where said 

facility is intended to serve single-family type dwellings; (3) embankments, bulkheads, 
retaining walls, or similar structures for erosion control to protect the existing shoreline; 

and (4) food plots and other wildlife enhancement. To the extent feasible and desirable to 

protect and enhance the project's scenic, recreational, and other environmental values, the 

licensee shall require multiple use and occupancy of facilities for access to project lands 

or waters. The licensee shall also ensure, to the satisfaction of the Commission's 

authorized representative, that the use and occupancies for which it grants permission are 

maintained in good repair and comply with applicable state and local health and safety 

requirements. Before granting permission for construction of bulkheads or retaining 

walls, the licensee shall: (1) inspect the site of the proposed construction, (2) consider 

whether the planting of vegetation or the use of riprap would be adequate to control 

erosion at the site, and (3) determine that the proposed construction is needed and would 

not change the basic contour of the impoundment shoreline. To implement this 

paragraph (b), the licensee may, among other things, establish a program for issuing 

permits for the specified types of use and occupancy of project lands and waters, which 

may be subject to the payment of a reasonable fee to cover the licensee's costs of 

administering the permit program. The Commission reserves the right to require the 

licensee to file a description of its standards, guidelines, and procedures for implementing 

this paragraph (b) and to require modification of those standards, guidelines, or 

procedures.

(c) The licensee may convey easements or rights-of-way across, or leases of 

project lands for: (1) replacement, expansion, realignment, or maintenance of bridges or 

roads where all necessary state and federal approvals have been obtained; (2) storm 

drains and water mains; (3)sewers that do not discharge into project waters; (4) minor 

access roads; (5) telephone, gas, and electric utility distribution lines; (6) non-project 

overhead electric transmission lines that do not require erection of support structures 

within the project boundary; (7) submarine, overhead, or underground major telephone 

distribution cables or major electric distribution lines (69-kV or less); and (8) water 

intake or pumping facilities that do not extract more than one million gallons per day 

from a project impoundment. No later than January 31 of each year, the licensee shall 

file three copies of a report briefly describing for each conveyance made under this 

paragraph (c) during the prior calendar year, the type of interest conveyed, the location of 

the lands subject to the conveyance, and the nature of the use for which the interest was 

conveyed. 

(d) The licensee may convey fee title to, easements or rights-of-way across, or 

leases of project lands for: (1) construction of new bridges or roads for which all 

necessary state and federal approvals have been obtained; (2) sewer or effluent lines that 
discharge into project waters, for which all necessary federal and state water quality 

certification or permits have been obtained; (3) other pipelines that cross project lands or 

waters but do not discharge into project waters; (4) non-project overhead electric 

transmission lines that require erection of support structures within the project boundary, 

for which all necessary federal and state approvals have been obtained; (5) private or 

public marinas that can accommodate no more than 10 water craft at a time and are 

located at least one-half mile (measured over project waters) from any other private or 

public marina; (6) recreational development consistent with an approved report on 

recreational resources of an Exhibit E; and (7) other uses, if: (i) the amount of land 

conveyed for a particular use is five acres or less; (ii) all of the land conveyed is located 

at least 75 feet, measured horizontally, from project waters at normal surface elevation; 

and (iii) no more than 50 total acres of project lands for each project development are 

conveyed under this clause (d)(7) in any calendar year. At least 60 days before 

conveying any interest in project lands under this paragraph (d), the licensee must file a 

letter with the Commission, stating its intent to convey the interest and briefly describing 

the type of interest and location of the lands to be conveyed (a marked Exhibit G map 

may be used), the nature of the proposed use, the identity of any federal or state agency 

official consulted, and any federal or state approvals required for the proposed use. 

Unless the Commission's authorized representative, within 45 days from the filing date, 

requires the licensee to file an application for prior approval, the licensee may convey the 

intended interest at the end of that period.

(e) The following additional conditions apply to any intended conveyance under 

paragraph (c) or (d) of this article:

(1) Before conveying the interest, the licensee shall consult with federal and state 

fish and wildlife or recreation agencies, as appropriate, and the State Historic 

Preservation Officer.

(2) Before conveying the interest, the licensee shall determine that the proposed 

use of the lands to be conveyed is not inconsistent with any approved report on 

recreational resources of an Exhibit E; or, if the project does not have an approved report 

on recreational resources, that the lands to be conveyed do not have recreational value.

(3) The instrument of conveyance must include the following covenants running 

with the land: (i) the use of the lands conveyed shall not endanger health, create a 

nuisance, or otherwise be incompatible with overall project recreational use; (ii) the 

grantee shall take all reasonable precautions to ensure that the construction, operation, 

and maintenance of structures or facilities on the conveyed lands will occur in a manner 
that will protect the scenic, recreational, and environmental values of the project; and 

(iii) the grantee shall not unduly restrict public access to project waters.

(4) The Commission reserves the right to require the licensee to take reasonable 

remedial action to correct any violation of the terms and conditions of this article, for the 

protection and enhancement of the project's scenic, recreational, and other 

environmental values.

(f) The conveyance of an interest in project lands under this article does not in 

itself change the project boundaries. The project boundaries may be changed to exclude 

land conveyed under this article only upon approval of revised Exhibit G drawings 

(project boundary maps) reflecting exclusion of that land. Lands conveyed under this 

article will be excluded from the project only upon a determination that the lands are not 

necessary for project purposes, such as operation and maintenance, flowage, recreation, 

public access, protection of environmental resources, and shoreline control, including 

shoreline aesthetic values. Absent extraordinary circumstances, proposals to exclude 

lands conveyed under this article from the project shall be consolidated for consideration 

when revised Exhibit G drawings would be filed for approval for other purposes.

(g) The authority granted to the licensee under this article shall not apply to any 

part of the public lands and reservations of the United States included within the 

project boundary.
APPENDIX C

DRAFT LICENSE ARTICLES

CONOWINGO HYDROELECTRIC PROJECT 
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Appendix C

Draft License Articles

Conowingo Hydroelectric Project 

Article 201. Administrative Annual Charges. The licensee shall pay the United 

States annual charges, effective the first day of the month in which the license is issued, 

and as determined in accordance with provisions of the Commission's regulations in 

effect from time to time, for the purposes of: 

(a) reimbursing the United States for the cost of administration of Part I of the 

Federal Power Act. The authorized installed capacity for that purpose is [the authorized 

capacity was previously determined to be 574,540 kW; but the value needs to be recomputed per the latest regulations after the ratings of each of the turbines and generators 

are verified] _______ megawatts. 

Article 202. Exhibit F Drawings. Within 45 days of the date of issuance of this 

license, as directed below, the licensee shall file the approved exhibit drawings in 

electronic file format on CD disks.

Digital images of the approved exhibit drawings shall be prepared in electronic 

format. Prior to preparing each digital image, the FERC Project-Drawing Number 

(i.e., P-405-1001 through P-405-###) shall be shown in the margin below the title block 

of the approved drawing. The licensee shall file two sets of exhibit drawings in 

electronic format on CD disks with the Secretary of the Commission, 

ATTN: OEP/DHAC. Exhibit F drawings must be identified as Critical Energy 

Infrastructure Information (CEII) material under 18 CFR §388.113(c). Each drawing 

must be a separate electronic file, and the file name shall include: FERC ProjectDrawing Number, FERC Exhibit, Drawing Title, date of this License, and file extension 

in the following format [P-405-####, F-1, Description, MM-DD-YYYY.TIF]. All digital 

images of the exhibit drawings shall meet the following format specification:

IMAGERY - black & white raster file 

FILE TYPE – Tagged Image File Format, (TIFF) CCITT Group 4 

RESOLUTION – 300 dpi desired, (200 dpi min)

DRAWING SIZE FORMAT – 24” x 36” (min), 28” x 40” (max)

FILE SIZE – less than 1 MB desired

Article 203. Exhibit G Drawings. Within 90 days of the effective date of the 

license, the licensee shall file, for Commission approval, revised Exhibit G drawings 
enclosing within the project boundary all principal project works necessary for operation 

and maintenance of the project, and reflecting the removal of 1,965 acres of lands from 

the current project boundary that do not contain existing project facilities and are not 

necessary for the operation and maintenance of the project. The Exhibit G drawings must 

comply with sections 4.39 and 4.41of the Commission’s regulations.

Article 204. Amortization Reserve. Pursuant to section 10(d) of the Federal 

Power Act, a specified reasonable rate of return upon the net investment in the project 

shall be used for determining surplus earnings of the project for the establishment and 

maintenance of amortization reserves. The licensee shall set aside in a project 

amortization reserve account at the end of each fiscal year one half of the project surplus 

earnings, if any, in excess of the specified rate of return per annum on the net investment. 

To the extent that there is a deficiency of project earnings below the specified rate of 

return per annum for any fiscal year, the licensee shall deduct the amount of that 

deficiency from the amount of any surplus earnings subsequently accumulated, until 

absorbed. The licensee shall set aside one-half of the remaining surplus earnings, if any, 

cumulatively computed, in the project amortization reserve account. The licensee shall 

maintain the amounts established in the project amortization reserve account until further 

order of the Commission.

The specified reasonable rate of return used in computing amortization reserves 

shall be calculated annually based on current capital ratios developed from an average of 

13 monthly balances of amounts properly included in the licensee's long-term debt and 

proprietary capital accounts as listed in the Commission's Uniform System of Accounts. 

The cost rate for such ratios shall be the weighted average cost of long-term debt and 

preferred stock for the year, and the cost of common equity shall be the interest rate on 

10-year government bonds (reported as the Treasury Department's 10-year constant 

maturity series) computed on the monthly average for the year in question plus four 

percentage points (400 basis points).

Article 205. Headwater Benefits. If the licensee's project was directly benefited 

by the construction work of another licensee, a permittee, or the United States on a 

storage reservoir or other headwater improvement during the term of the original license 

(including extensions of that term by annual licenses), and if those headwater benefits 

were not previously assessed and reimbursed to the owner of the headwater 

improvement, the licensee shall reimburse the owner of the headwater improvement for 

those benefits, at such time as they are assessed, in the same manner as for benefits 

received during the term of this new license. The benefits will be assessed in accordance 

with Part 11, Subpart B, of the Commission's regulations.
Article 301. Public Safety Plan. At least 60 days prior to reopening of the 

Conowingo powerhouse catwalk or installation of any new recreation facilities, the 

licensee shall submit one copy to the Commission’s Division of Dam Safety and 

Inspections (D2SI) - New York Regional Engineer and two copies to the Commission 

(one of these copies shall be a courtesy copy to the Commission’s Director, D2SI) of an 

updated Public Safety Plan. The plan shall include an updated evaluation of public safety 

concerns at the project site, including all updated designated recreation areas, and assess 

the need for the installation of safety devices or other safety measures. The submitted 

plan should include a description of all public safety devices and signage, as well as a 

map showing the location of all public safety measures. For guidance on preparing 

public safety plans the licensee can review the Guidelines for Public Safety at 

Hydropower Projects on the FERC website.

Article 302. Project Modification Resulting From Environmental Requirements. 

Any permanent or temporary modification which may affect the project works or 

operations shall be coordinated with the Commission’s Division Dam Safety and 

Inspections (D2SI) - New York Regional Engineer at the beginning of the planning and 

design phase. This includes those modifications resulting from license environmental 

requirements. This schedule is to allow sufficient review time for the Commission to 

insure that the proposed work does not adversely affect the project works, dam safety or 

project operation.

Article 401. Sediment Management Plan. The Sediment Management Plan, filed 

on August 31, 2012, is approved with the following modifications: 

(1) Include a provision to conduct dredging with the frequency and depth 

needed to maintain the navigation channel at the Conowingo Creek, Peters 

Creek (Peach Bottom Marina), and Broad Creek boat ramps, where 

sediments have been accumulating, in order to improve and maintain 

recreational boating access. 

(2) Beginning in 2016, the licensee shall conduct a bathymetric survey of 

Conowingo Pond at 5-year intervals to monitor sediment transport and 

depositional patterns within the pond. The licensee shall file the results of 

each bathymetric survey with the Commission by March 31 of the 

following year. The results of each bathymetric survey shall include an

analysis of any change in sediment deposition or scour in the pond from the 
previous survey(s), including the 2011 survey,1 so that any changes in 

sediment depositional or scour patterns in the pond over time since the 

2011 survey can be monitored.

The Sediment Management Plan, as modified, shall be made part of this license, 

and may not be amended without prior Commission approval. Upon license issuance, the 

licensee shall implement the plan according to the schedule included in the plan. The 

Commission reserves the right to require any additional changes to the plan.

Article 402. Conowingo Pond Level Management. Upon license issuance, the 

licensee shall operate the project within a normal range for Conowingo Pond between 

elevations 101.2 feet National Geodetic Vertical Datum of 1929 (NGVD) and 110.2 

feet NGVD, with a minimum elevation of 107.2 feet NGVD on weekends between 

Memorial Day and Labor Day, to meet recreational needs.

Conowingo pond level may be temporarily modified if required by operating 

emergencies beyond the control of the licensee, and for short periods upon mutual 

agreement among the licensee, the Pennsylvania Department of Environmental 

Protection, and Maryland Department of the Environment. If minimum flows are so 

modified, the licensee shall notify the Commission, in writing, as soon as possible, but no 

later than 10 days after each such incident. 

Article 403. Minimum Flow Requirements. Upon license issuance, the licensee 

shall provide minimum flow releases from the project, as described below, or a minimum 

flow equal to the natural inflow as measured at the Marietta U.S. Geological Survey gage 

(No. 01576000), whichever is less, according to the following schedule:

September 15 – March 31: 3,500 cubic feet per second (cfs) or natural inflow; 

April 1 – April 30: 10,000 cfs or natural inflow;

May 1 – June 15: 7,500 cfs or natural inflow; and

June 16 – September 14: 5,000 cfs or natural inflow.

Minimum flow releases may be temporarily modified if required by operating 

emergencies beyond the control of the licensee, and for short periods upon mutual 

 1 Exelon Generation Corp. conducted a bathymetric survey of Conowingo Pond in 

support of Conowingo Study Revised Study Plan 3.15: Sediment Introduction and 

Transport study, and filed with the Commission on February 23, 2012.
agreement among the licensee and the Maryland Department of the Environment. If 

minimum flows are so modified, the licensee shall notify the Commission, in writing, as 

soon as possible, but no later than 10 days after each such incident. 

Article 404. Dissolved Oxygen Enhancements and Monitoring. Upon license 

issuance, the licensee shall continue the dissolved oxygen (DO) enhancement at the 

project using the turbine venting systems on units 1-7 and the aerating runners on 

units 2 and 5. DO levels shall be continuously monitored from May 1 through October 1 

at the Station 643 location, about 0.6 mile downstream of Conowingo dam. By January 1 

of each year, the licensee shall file a report on the results of the previous year’s DO 

monitoring at the project.

Article 405. Reservation of Authority to Prescribe Fishways. Authority is 

reserved to the Commission to require the licensee to construct, operate, and maintain, or 

provide for the construction, operation, and maintenance of, such fishways as may be 

prescribed by the Secretary of the Interior and/or Commerce pursuant to section 18 of the 

Federal Power Act.

Article 406. Continued Fish Passage Operation. The licensee shall continue to 

operate the east fish lift as the primary facility for volitional upstream fish passage, with a 

preventive maintenance program to extend the useful life of the facility through the 

license term, along with other improvements required by Article 407. The licensee shall 

continue to operate the project turbines as the primary route for downstream fish passage 

of American shad and river herring. The licensee shall also continue to coordinate annual 

fish passage operations with the Susquehanna River Anadromous Fish Restoration 

Cooperative and its member agencies and other entities.

Article 407. Upstream Fish Passage Improvements. The licensee shall 

implement measures to update and improve the effectiveness of upstream fish passage at 

the project by modifying the east and west fish lifts as follows: 

(1) replace the existing hopper at the west fish lift with a 1,500-gallon hopper;

(2) improve the west fish lift sorting and loading process to facilitate trap and 

truck operations, and implement a trap and truck program for American shad;

(3) conduct a feasibility study for adding attraction flow at the west fish lift and, if 

feasible and beneficial, install additional flow capacity; 

(4) restore the original design for the 900-cubic feet per second (cfs) attraction 

flow in the east fish lift;
(5) add a second 3,300-gallon hopper to the east fish lift in the space provided for 

in the original design, and upgrade the electrical and mechanical equipment to 

allow for a 15-minute lift cycle; and

(6) if 2 years of effectiveness studies, after restoration of the 900-cfs attraction 

flow, show poor attraction at the east fish lift for adult American shad, conduct

a feasibility study for modifying the locations of entrances A and B, and 

implement those modifications if feasible.

Within 6 months of license issuance, the licensee shall file with the Commission 

for approval, a detailed plan for implementing these fish passage improvements, 

developed after consultation with the U.S. Fish and Wildlife Service, National Marine 

Fisheries Service, Pennsylvania Fish and Boat Commission, and Maryland Department of 

Natural Resources. The licensee shall include with the plan an implementation schedule, 

documentation of consultation, copies of recommendations on the completed plan after it 

was prepared and provided to the entities above, and specific descriptions of how the 

entities’ comments are accommodated by the plan. The licensee shall provide a 

minimum of 30 days for the entities to comment and to make recommendations before 

filing the plan with the Commission. If the licensee does not adopt a recommendation, 

the filing shall include the licensee’s reasons, based on project-specific reasons.

The Commission reserves the right to require changes to the plan. Implementation 

of the plan shall not begin until the licensee is notified by the Commission that the plan is 

approved. Upon Commission approval, the licensee shall implement the plan, including 

any changes required by the Commission.

Article 408. Downstream American Eel Passage. The licensee shall participate in 

a trap and transport program for downstream American eel passage, in cooperation with 

the operators and licensees of the York Haven Hydroelectric Project (FERC No. 1888), 

the Safe Harbor Hydroelectric Project (FERC No. 1025) and the Holtwood Hydroelectric 

Project (FERC No. 1881) on the lower Susquehanna River. This program may include a 

program to trap and transport adult American eels from smaller tributaries upstream of 

the York Haven Project (FERC No. 1888), or other measures to ensure safe and timely 

downstream passage. Because no timetable has yet been established for this cooperative 

program, the licensee shall file periodic progress reports with the Commission on the 

status of the program, beginning within 5 years of license issuance, and continuing on a 

5-year interval, unless later modified by the Commission.

Article 409. Debris Management Program. Upon license issuance, the licensee 

shall implement a debris management program that includes clamming (with three gantry 
cranes with grapple attachments) to remove submerged debris from the area upstream of 

the powerhouse intakes and floating surficial debris in front of the powerhouse intakes, 

and the sponsorship of community-based clean-ups in the pond and downstream of 

the dam as described in the final license application and the Debris Management Study 

Final Study Report filed with the Commission on August 31, 2012.

Article 410. Bald Eagle Management Plan. The Bald Eagle Management Plan, 

filed on August 29, 2012, is approved with the following modifications:

(1) require enforcement of human traffic restrictions on both sides of Rowland 

Island, under the towers in the river, and on the Cecil County side of the 

river where current human activities disturb perching and foraging eagles at 

eagle concentration areas; and

(2) before any ground-disturbing work begins within the project boundary, the 

licensee shall visit the U.S. Fish and Wildlife Service’s Chesapeake Bay 

Field Office and Pennsylvania Field Office websites and comply with 

current bald eagle management guidelines. If there are updated guidelines, 

the licensee shall revise the BEMP to incorporate any new guidelines 

issued by the FWS during the term of the license and provide the revised 

BEMP to the Commission for approval.

The Bald Eagle Management Plan, as modified, shall be made part of this license, 

and may not be amended without prior Commission approval. Upon license issuance, the 

licensee shall implement the plan according to the schedule included in the plan. The 

Commission reserves the right to require any additional changes to the plan.

Article 411. Northern Map Turtle Protection Plan. Within 6 months of license 

issuance, the licensee shall file, for Commission approval, a northern map turtle 

protection plan for the protection and enhancement of the map turtle population.

The plan shall include, at a minimum:

(1) nest management and alternative basking site mitigation and protection 

measures identified and studied during the ongoing Towson University map 

turtle studies;

(2) annual monitoring of the northern map turtle population at the project for 

10 years; 

(3) annual monitoring of the use and success of both the mitigation and protection 

measures for 10 years; 
(4) an assessment of the northern map turtle’s response to any change in operating 

regime as a result of the license; and 

(5) methods of altering or amending protection and mitigation measures as a result 

of the monitoring, in consultation with the Maryland Department of Natural 

Resources (Maryland DNR).

The plan shall be developed after consultation with the Maryland DNR and 

Towson University. The licensee shall include with the plan an implementation schedule, 

documentation of consultation, copies of recommendations on the completed plan after it 

has been prepared and provided to the entities above, and specific descriptions of how the 

entities’ comments are accommodated by the plan. The licensee shall provide a 

minimum of 30 days for the entities to comment and to make recommendations before 

filing the plan with the Commission. If the licensee does not adopt a recommendation, 

the filing shall include the licensee’s reasons, based on project-specific reasons.

The Commission reserves the right to require changes to the plan. Implementation 

of the plan shall not begin until the licensee is notified by the Commission that the plan is 

approved. Upon Commission approval, the licensee shall implement the plan, including 

any changes required by the Commission.

Article 412. Waterfowl Nesting Protection Plan. Within 6 months of license 

issuance, the licensee shall file, for Commission approval, a waterfowl nesting protection 

plan. The plan shall identify waterfowl nesting areas affected by the project that are 

vulnerable to flooding during the nesting season, identify a range of alternatives to avoid 

flooding active nests, and provide recommendations to avoid flooding active nests. 

The plan shall be developed after consultation with the U.S. Fish and Wildlife 

Service, Pennsylvania Fish and Boat Commission, and the Maryland Department of 

Natural Resources. The licensee shall include with the plan an implementation schedule, 

documentation of consultation, copies of recommendations on the completed plan after it 

has been prepared and provided to the entities above, and specific descriptions of how the 

entities’ comments are accommodated by the plan. The licensee shall provide a 

minimum of 30 days for the entities to comment and to make recommendations before 

filing the plan with the Commission. If the licensee does not adopt a recommendation, 

the filing shall include the licensee’s reasons, based on project-specific reasons.

The Commission reserves the right to require changes to the plan. Implementation 

of the plan shall not begin until the licensee is notified by the Commission that the plan is 
approved. Upon Commission approval, the licensee shall implement the plan, including 

any changes required by the Commission.

Article 413. Recreation Management Plan. The Recreation Management Plan,

filed on August 31, 2012, is approved with the following modifications: 

(1) conduct a recreation use study every 12 years throughout the license 

term, consistent with every other FERC Form 80 reporting period 

deadline, to ensure the proposed plans are current and the sites are 

meeting the demand;

(2) include a provision to review the results of the bathymetric mapping

and dredging occurring periodically at the Conowingo Creek, Peters 

Creek (Peach Bottom Marina), and Broad Creek boat ramp as required 

by the Sediment Management Plan (Article 401) intended to ensure 

boater access to the reservoir at these locations.

(3) update the plan every 12 years in concert with every other Form 80 

reporting period; and

(4) develop a plan to provide limited access to the catwalk for anglers, with 

security measures in place that address the vulnerability of the facility 

and the safety of the users of the catwalk. Such measures could include, 

but not be limited to, on-site inspections, video surveillance, prescreening procedures, capacity limits, security personnel, and physical 

infrastructure modifications. The ultimate decision on whether the 

catwalk can be reopened to the public, even on a limited basis, is

dependent upon the Commission’s evaluation of the plan and whether it 

satisfies public safety and security concerns.

Each update to the Recreation Management Plan shall be developed in 

consultation with the U.S. Fish and Wildlife Service, the Pennsylvania Department of 

Conservation and Natural Resources, and the Maryland Department of the Environment. 

The licensee shall include with the updated plans an implementation schedule, 

documentation of consultation, copies of recommendations on the completed plan after it 

has been prepared and provided to the entities above, and specific descriptions of how the 

entities’ comments are accommodated by the plan. The licensee shall provide a 

minimum of 30 days for the entities to comment and to make recommendations before 

filing the updated plans with the Commission. If the licensee does not adopt a 

recommendation, the filing shall include the licensee’s reasons, based on project-specific 

reasons.
The licensee shall continue to operate and maintain the following existing 

facilities for the term of the license: (1) Lock 13, (2) Lock 15, (3) Muddy Creek Boat 

Launch, (4) Cold Cabin Boat Launch, (5) Dorsey Park, (6) Line Bridge, (7) Broad Creek 

Public Landing, (8) Glen Cove Marina, (9) Conowingo swimming pool and visitor’s 

center, (10) Peach Bottom Marina, (11) Conowingo Creek Boat Launch, (12) Funks 

Pond, (13) Fisherman’s Park/Shures Landing, and (14) Octoraro Creek Access. If the 

licensee proposes changes to the existing facilities, the licensee shall file the changes with 

the Commission for approval.

The Recreation Management Plan, as modified, shall be made part of this license, 

and may not be amended without prior Commission approval. Upon license issuance, the 

licensee shall implement the plan according to the schedule included in the plan. The 

Commission reserves the right to require any additional changes to the plan.

Article 414. Shoreline Management Plan. The Shoreline Management Plan filed 

on August 31, 2012, is approved, with the following modification: update and file the 

plan with the Commission every 10 years. 

Each update to the plan shall be developed in consultation with the U.S. Fish and 

Wildlife Service, the Pennsylvania Department of Conservation and Natural Resources,

and the Maryland Department of the Environment. The licensee shall include with the

updated plans an implementation schedule, documentation of consultation, copies of 

recommendations on the completed plan after it has been prepared and provided to the 

entities above, and specific descriptions of how the entities’ comments are 

accommodated by the plan. The licensee shall provide a minimum of 30 days for the 

entities to comment and to make recommendations before filing the updated plans with 

the Commission. If the licensee does not adopt a recommendation, the filing shall 

include the licensee’s reasons, based on project-specific reasons.

The Shoreline Management Plan, as modified, shall be made part of this license, 

and may not be amended without prior Commission approval. Upon license issuance, the 

licensee shall implement the plan according to the schedule included in the plan. The 

Commission reserves the right to require any additional changes to the plan.

Article 415. Programmatic Agreement and Historic Properties Management 

Plan. Upon license issuance, the licensee shall implement the Programmatic Agreement 

Between the Federal Energy Regulatory Commission, the Pennsylvania Historic 

Preservation Officer, and the Maryland Historic Preservation Officer for Managing 

Historic Properties that May be Affected by Issuing a New License to Exelon Generation 
Company, LLC, for the Continued Operation of the Conowingo Project in Lancaster and 

York counties, Pennsylvania, and Cecil and Harford counties, Maryland 

(FERC No.405-106), executed on ____________, and including but not limited to the 

Historic Properties Management Plan (HPMP) for the project. Pursuant to the 

requirements of this Programmatic Agreement, the licensee shall file, for Commission 

approval, a revised HPMP within six months of issuance of this order. The revised 

HPMP shall be based on the HPMP filed with the Commission on August 31, 2012, and 

include the following:

(a) a revised area of potential effects (APE) with the narrow strip of land in the 

current project boundary extending downstream from Spencer Island along the 

west side of the river to Havre de Grace;

(b) a discussion of all 48 sites and 27 historic structures identified to date 

within the project APE or an explanation of why they are not considered eligible; 

(c) a correction to identify the Susquehanna and Tidewater Canal and 

Columbia & Port Deposit Railroad as eligible for listing; 

(d) a provision to inventory any lands within the revised APE, evaluate 

identified cultural resources for eligibility, and address potential effects before sale 

or transfer of those lands; 

(e) a provision to make good faith effort to obtain access to private property to 

conduct studies if effects on cultural resources on private lands are identified; 

(f) a revised list of project activities involving the Conowingo Project system 

that can be completed without Maryland State Historic Preservation Officer 

(SHPO) review; 

(g) a process for assessing project-related ground-disturbing activities to 

determine whether or not archaeological sites would be affected, particularly in 

areas that have not had archaeological surveys; 

(h) provisions to ensure confidentiality of cultural resources location 

information during implementation of public outreach programs; and 

(i) a description of project-related activities that will require tribal consultation

in accordance with section 106 of the National Historic Preservation Act.

The Commission reserves the authority to require changes to the HPMP at any 

time during the term of the license. If the Programmatic Agreement is terminated prior to 
Commission approval of the HPMP, the licensee shall obtain approval from the 

Commission and the Pennsylvania and Maryland SHPOs, before engaging in any grounddisturbing activities or taking any other action that may affect any historic properties 

within the project's APE.

Article 16. Use and Occupancy. (a) In accordance with the provisions of this 

article, the licensee shall have the authority to grant permission for certain types of use 

and occupancy of project lands and waters and to convey certain interests in project lands 

and waters for certain types of use and occupancy, without prior Commission approval. 

The licensee may exercise the authority only if the proposed use and occupancy is 

consistent with the purposes of protecting and enhancing the scenic, recreational, and 

other environmental values of the project. For those purposes, the licensee shall also 

have continuing responsibility to supervise and control the use and occupancies for which 

it grants permission, and to monitor the use of, and ensure compliance with the covenants 

of the instrument of conveyance for, any interests that it has conveyed, under this article. 

If a permitted use and occupancy violates any condition of this article or any other 

condition imposed by the licensee for protection and enhancement of the project's scenic, 

recreational, or other environmental values, or if a covenant of a conveyance made under 

the authority of this article is violated, the licensee shall take any lawful action necessary 

to correct the violation. For a permitted use or occupancy, that action includes, if 

necessary, canceling the permission to use and occupy the project lands and waters and 

requiring the removal of any non-complying structures and facilities.

(b) The type of use and occupancy of project lands and waters for which the 

licensee may grant permission without prior Commission approval are: (1) landscape 

plantings; (2) non-commercial piers, landings, boat docks, or similar structures and 

facilities that can accommodate no more than 10 water craft at a time and where said 

facility is intended to serve single-family type dwellings; (3) embankments, bulkheads, 

retaining walls, or similar structures for erosion control to protect the existing shoreline; 

and (4) food plots and other wildlife enhancement. To the extent feasible and desirable to 

protect and enhance the project's scenic, recreational, and other environmental values, the 

licensee shall require multiple use and occupancy of facilities for access to project lands 

or waters. The licensee shall also ensure, to the satisfaction of the Commission's 

authorized representative, that the use and occupancies for which it grants permission are 

maintained in good repair and comply with applicable state and local health and safety 

requirements. Before granting permission for construction of bulkheads or retaining 

walls, the licensee shall: (1) inspect the site of the proposed construction, (2) consider 

whether the planting of vegetation or the use of riprap would be adequate to control 
erosion at the site, and (3) determine that the proposed construction is needed and would 

not change the basic contour of the impoundment shoreline. To implement this 

paragraph (b), the licensee may, among other things, establish a program for issuing 

permits for the specified types of use and occupancy of project lands and waters, which 

may be subject to the payment of a reasonable fee to cover the licensee's costs of 

administering the permit program. The Commission reserves the right to require the 

licensee to file a description of its standards, guidelines, and procedures for implementing 

this paragraph (b) and to require modification of those standards, guidelines, or 

procedures.

(c) The licensee may convey easements or rights-of-way across, or leases of 

project lands for: (1) replacement, expansion, realignment, or maintenance of bridges or 

roads where all necessary state and federal approvals have been obtained; (2) storm 

drains and water mains; (3) sewers that do not discharge into project waters; (4) minor 

access roads; (5) telephone, gas, and electric utility distribution lines; (6) non-project 

overhead electric transmission lines that do not require erection of support structures 

within the project boundary; (7) submarine, overhead, or underground major telephone 

distribution cables or major electric distribution lines (69-kV or less); and (8) water 

intake or pumping facilities that do not extract more than one million gallons per day 

from a project impoundment. No later than January 31 of each year, the licensee shall 

file three copies of a report briefly describing for each conveyance made under this 

paragraph (c) during the prior calendar year, the type of interest conveyed, the location of 

the lands subject to the conveyance, and the nature of the use for which the interest 

was conveyed. 

(d) The licensee may convey fee title to, easements or rights-of-way across, or 

leases of project lands for: (1) construction of new bridges or roads for which all 

necessary state and federal approvals have been obtained; (2) sewer or effluent lines that 

discharge into project waters, for which all necessary federal and state water quality 

certification or permits have been obtained; (3) other pipelines that cross project lands or 

waters but do not discharge into project waters; (4) non-project overhead electric 

transmission lines that require erection of support structures within the project boundary, 

for which all necessary federal and state approvals have been obtained; (5) private or 

public marinas that can accommodate no more than 10 water craft at a time and are 

located at least one-half mile (measured over project waters) from any other private or 

public marina; (6) recreational development consistent with an approved report on 

recreational resources of an Exhibit E; and (7) other uses, if: (i) the amount of land 

conveyed for a particular use is five acres or less; (ii) all of the land conveyed is located 
at least 75 feet, measured horizontally, from project waters at normal surface elevation; 

and (iii) no more than 50 total acres of project lands for each project development are 

conveyed under this clause (d)(7) in any calendar year. At least 60 days before 

conveying any interest in project lands under this paragraph (d), the licensee must file a 

letter with the Commission, stating its intent to convey the interest and briefly describing 

the type of interest and location of the lands to be conveyed (a marked Exhibit G map 

may be used), the nature of the proposed use, the identity of any federal or state agency 

official consulted, and any federal or state approvals required for the proposed use. 

Unless the Commission's authorized representative, within 45 days from the filing date, 

requires the licensee to file an application for prior approval, the licensee may convey the 

intended interest at the end of that period.

(e) The following additional conditions apply to any intended conveyance under 

paragraph (c) or (d) of this article:

(1) Before conveying the interest, the licensee shall consult with federal and state 

fish and wildlife or recreation agencies, as appropriate, and the State Historic 

Preservation Officer.

(2) Before conveying the interest, the licensee shall determine that the proposed 

use of the lands to be conveyed is not inconsistent with any approved report on 

recreational resources of an Exhibit E; or, if the project does not have an approved report 

on recreational resources, that the lands to be conveyed do not have recreational value.

(3) The instrument of conveyance must include the following covenants running 

with the land: (i) the use of the lands conveyed shall not endanger health, create a 

nuisance, or otherwise be incompatible with overall project recreational use; (ii) the 

grantee shall take all reasonable precautions to ensure that the construction, operation, 

and maintenance of structures or facilities on the conveyed lands will occur in a manner 

that will protect the scenic, recreational, and environmental values of the project; and (iii) 

the grantee shall not unduly restrict public access to project waters.

(4) The Commission reserves the right to require the licensee to take reasonable 

remedial action to correct any violation of the terms and conditions of this article, for the 

protection and enhancement of the project's scenic, recreational, and other environmental 

values.

(f) The conveyance of an interest in project lands under this article does not in 

itself change the project boundaries. The project boundaries may be changed to exclude 

land conveyed under this article only upon approval of revised Exhibit G drawings 
(project boundary maps) reflecting exclusion of that land. Lands conveyed under this 

article will be excluded from the project only upon a determination that the lands are not 

necessary for project purposes, such as operation and maintenance, flowage, recreation, 

public access, protection of environmental resources, and shoreline control, including 

shoreline aesthetic values. Absent extraordinary circumstances, proposals to exclude 

lands conveyed under this article from the project shall be consolidated for consideration 

when revised Exhibit G drawings would be filed for approval for other purposes.

(g) The authority granted to the licensee under this article shall not apply to any 

part of the public lands and reservations of the United States included within the 

project boundary.
APPENDIX D

Preliminary Fishway Prescription – York Haven Hydroelectric Project
1

9. Preliminary Prescription for Fishways

Pursuant to section 18 of the Federal Power Act, as amended, the Secretary of the Department of 

the Interior, as delegated to the Service, proposes to exercises her authority to prescribe the 

construction, operation and maintenance of such fishways as deemed necessary, subject to the 

procedural provisions contained in Section 2 above.

The Department’s Preliminary Prescription for Fishways reflects a number of issues and concerns

related to fish restoration and passage that have been raised by the Licensee, Commission staff, 

state resource agencies, and other parties involved in these proceedings. Moreover, the

Department, through the Service, reached settlement with the Licensee on matters of fish passage. 

The full range of issues settled are described in the Settlement Agreement, which includes its 

appendices.

Fishways shall be constructed, operated, and maintained to provide safe, timely and effective 

passage for American shad, alewife, blueback herring, and American eels and other designated 

resident riverine fish species at the Licensee's expense.

To ensure the immediate and timely contribution of the fishways to the ongoing and planned 

anadromous and catadromous fish restoration and enhancement program in the Susquehanna 

River, the following are included and shall be incorporated by the Commission to ensure the 

effectiveness of the fishways pursuant to section 1701(b) of the 1992 National Energy Policy Act 

(P.L. 102-486, Title XVII, 106 Stat. 3008).

9.1 Design Population: American Shad

Fish passage needs to be adequate to maintain self-sustaining annual populations of two million 

American shad reproducing in the free-flowing Susquehanna River above York Haven Dam and 

in suitable tributaries.

9.2 Design Population: River Herring (Alewife and Blueback Herring)

Fish passage needs to be adequate to maintain self-sustaining annual populations of five million 

river herring, reproducing in the free-flowing Susquehanna River above York Haven Dam and in 

suitable tributaries.

9.3 Design Population: American Eel

Fish passage needs to be adequate to pass all available upstream migrating eels that arrive to York 

Haven Dam to the mainstem of the Susquehanna River above the Project. Downstream migration 

of adult eels must be safe, timely and effective, achieving an 85% survival rate past the Project.
2

9.4 Operational Flows

Licensee shall operate the Project consistent with the flow management targets set forth below. 

The flow values set forth in this section are understood to be approximate and based upon 

reasonable engineering estimates.

9.4.1 Prior to NLF Facility Completion

Prior to completion and operation of the NLF Facility, Licensee shall operate the Project 

consistent with the following flow management criteria.

a. During the American Shad Upstream Passage Season

i) An average daily minimum flow in East Channel below East Channel Dam of

2,000 cfs.

ii) Spill over the Main Dam of equal to or greater than 4,000 cfs.

b. After the American Shad Upstream Passage Season until end of resident fish passage 

season (earlier of December 15 or until the average daily river temperature is less

than or equal to 40 degrees Fahrenheit for three consecutive days)

i) The Project shall be operated to provide a minimum stream flow in the East

Channel below East Channel Dam of 400 cfs.

ii) When river flows exceed hydraulic capacity of all available hydroelectric 

generating units, Licensee shall manage flows above the hydraulic capacity of 

available units in accordance with the following objectives:

(1) To maintain the minimum flow in the East Channel of 400 cfs.

(2) To maintain sufficient flow at the Main Dam to assure flow is released to 

the main channel in accordance with the existing Fish Passage Operational 

Plan (FPOP), except during times of maintenance work on the Main Dam 

when reservoir levels are lowered to permit such maintenance to occur 

safely.

(3) To provide additional attraction flows to the East Channel Fish Passage

System through operation of the wheel gates within their design capacity.

9.4.2 After NLF Facility Completion

After completion and operation of the NLF Facility, Licensee shall operate the Project consistent 

with the following flow management criteria
3

a. During the American Shad Upstream Passage Season:

i) An average daily minimum flow in East Channel below East Channel Dam of 

a minimum of 267 cfs, understanding that as river flow increases above 21,000 

cfs, flows over the East Channel Dam will occur in excess of the minimum of

267 cfs.

ii) Flow through the NLF Facility (passage channel plus supplement attraction 

flow channel) equal to at least 5% of river flow when river flows above the 

Project are between 5,000 and 150,000 cfs.

b. During the remainder of the year, the project shall be operated to provide:

i) An average daily minimum flow in the East Channel below the East Channel 

Dam of 267 cfs.

ii) The NLF Facility will be designed and operated to convey a minimum of 200 

cfs when the river elevation is at the elevation of the Main Dam

iii) When river flows exceed the hydraulic capacity of all available hydroelectric 

generating units, the Licensee shall manage flows above the hydraulic 

capacity of available units in accordance with the following objectives:

(1) To maintain a minimum flow in the East Channel of 267 cfs, understanding

that as river flow increases above 21,000 cfs, flows over the East Channel Dam 

will occur in excess of the minimum of 267 cfs.

(2) To maximize the remainder of flows abo ve hydraulic capacity flowing 

over the Main Dam and through the NLF facility. Within the limits of 

available flows in excess of the hydraulic capacity, except during the 

period of December 15 to the earlier of April 1 or the start of the 

American Shad Upstream Passage Season, the supplemental attraction 

flow channel will be operated with the objective of maintaining a 

maximum attraction flow through the NLF Facility.

9.5 Scheduling

The timely installation of the prescribed fishway structures, facilities, or devices is a measure 

directly related to those structures, facilities, or devices and is necessary to ensure the 

effectiveness of such structures, facilities, or devices. Therefore, the Department's Prescription 

includes the express requirement that the Licensee notify and obtain approval from the Service 

for any extensions of time to comply with the provisions included in the Department's 

Prescriptions for fishways.

Regarding the timing of seasonal fishway operations, fishways shall be maintained and operated, 

at the Licensee's expense, to maximize fish passage effectiveness throughout the upstream and 

downstream migration periods for American shad, alewife, blueback herring, American eel, and 

designated resident riverine fish.
4

Table 1. Upstream and downstream migration periods for species covered in this Prescription 

for Fishways. (*)

Species Upstream Migration Period Downstream Migration

Period

American shad April 1 through June 15 July 1 through November 15 

(juv.)

April 15 through July 1 (adult)

Alewife & blueback herring March 1** through June 15 June 15 through October 14 

(juv.)

April 15 through July 1 (adult)

American eel April 1 through December 1, 

or whenever river temperature 

is above 50 degrees F ***

September 15–February 15,

or whenever river temperature 

is above 37 degrees F ****

* Any of these migration periods may be changed during the term of the license by the 

Department, based on new information, and in consultation with the other fishery agencies and 

the licensee.

** This operational period is based on Alewife migration timing from other tributaries to the

Chesapeake Bay (Sutherland 2000, Eyler et al. 2002, Slacum 2003)

***This initial operational period is based on preliminary data on American eel migration timing 

from other tributaries to the Chesapeake Bay.

**** The Department is calling for the licensee to study the magnitude and timing of downstream 

eel migration through the project so that the effectiveness of a reduced period can be evaluated. 

This initial operational period is based on preliminary data on American eel migration timing from 

other tributaries to the Chesapeake Bay (Welsh et al. 2009).

9.6 Specific Prescriptions for the York Haven Project

9.7 General Requirements

9.8 Fishway Operating Procedures (FOP)

a. The FOP will include, for each fishway, schedules for routine maintenance, 

procedures for routine operations (including: seasonal and daily periods of 

operation, dam and powerhouse operational measures) detailing with how the 

plant shall be operated during fish passage season including sequencing of turbine 

start-up and operation, debris management as well as any other necessary 

provisions for plant operation and related to attraction flow as a component of the 

fish passage system to the operation of the NLF, procedures for monitoring and

reporting on the operation, and procedures for use in case of emergencies and

Project outages significantly affecting fishway operations.

b. The Licensee shall implement the FOP consistent with the approval of the Service. 

The Licensee shall provide written documentation to the Resource Agencies that 
5

all fishway operational personnel have reviewed and understand the FOP signed 

by the operations manager of the Amended Project.

c. Copies of the approved FOP and all modifications will be provided to the Resource

Agencies.

d. By December 31 of each year, following commencement of the Amended Project, 

the Licensee shall provide an annual report detailing; the implementation of the 

FOP, including any deviations from the FOP and a process to prevent those 

deviations in the future to the Resource Agencies; any proposed modifications to 

the FOP, or in the case of emergencies or Project outages, the steps taken by the 

Licensee to minimize adverse effects on fishway operation or fish passage 

measures; and any proposed modifications to those steps to further enhance their 

effectiveness in the future. The Licensee shall meet with the Resource Agencies by

January 31 of each year unless a different date is mutually agreed upon by the 

Licensee and the Resource Agencies. Any required modifications to the FOP shall 

be submitted to the Resource Agencies within 30 days of receipt of a request for 

the modification unless a longer period is approved by the Service. The 

modifications to the FOP shall be implemented consistent with the approval of the 

Service. Nothing herein shall require the Licensee to make operational or

structural changes related to the fish passage facilities and measures beyond those 

changes provided for in Section 9.9 hereof.

e. For fish passage system enhancements and facilities that do not begin operation 

with the entry into operation of the Amended Project, 60 days prior to operation 

of the enhancements and/or facilities, the Licensee shall submit FOP provisions 

for any such new fish passage enhancements, facilities and measures to the 

Resource Agencies for review and approval and shall implement the FOP as 

approved by the Service.

9.9 Fish Protection and Passage

9.9.1 Upstream Fish Passage / Nature-Like Fishway Construction

a. Licensee shall finance, design, permit and install a nature-like fishway facility 

(NLF Facility) in the vicinity of the apex of the Main Dam and Three Mile Island 

(TMI) in substantial compliance with the design criteria for the NLF Facility set 

forth in the Settlement Agreement. Licensee shall complete engineering design, 

apply for and obtain required governmental approvals, construct, and place into 

operation the NLF Facility by November 30, 2021.

b. In consultation with the Resource Agencies, Licensee shall develop the final plans 

and specifications for the NLF consistent with the design concept and design 

criteria in Appendix A, 1and shall submit such plans and specifications to the 

Resource Agencies, Licensee shall provide a minimum of 60 days for the

 1 Appendix A, D, E, G, and H are included by reference. They are integral to and attached to the

Settlement Agreement on which this Preliminary Prescription for Fishways is based.
6

Resource Agencies to submit comments on such plans and for review by the 

Service and PADEP. Such comments, review and approval shall not result in a 

material change. After approval of such plans by PADEP and the Service, 

Licensee shall submit such plans to the Commission for approval. Licensee shall 

include the final plans submitted to the Commission evidence of Licensee does not 

adopt a recommendation made by a Resource Agency other than PADEP and the

Service, the filing shall include the Licensee’s reasons together with supporting

information. The plans shall not be implemented until the Licensee is notified that 

the plans are approved by the Commission. Upon Commission approval and the

receipt of all other required governmental approvals, the Licensee shall implement 

the plans, including any changes required by the Commission.

9.9.2 NLF Facility Operations

Following construction of the NLF Facility, Licensee shall perform all required routine 

maintenance of the NLF Facility. Licensee shall conduct periodic inspections of the NLF 

Facility; and manage and remove debris from the NLF Facility to maintain the functioning and 

operability of the NLF Facility sufficient to allow and not significantly impede the passage of 

fish.

Licensee shall prepare an NLF Facility operations and maintenance plan (the “NLF O&M Plan”), 

and will submit the NLF O&M Plan for review by the Resource Agencies and for approval by

PADEP and the Service. Following review and comment by the Resource Agencies, and 

approval by PADEP and Service, the Licensee shall submit the NLF O&M Plan to FERC, and 

shall implement the NLF O&M Plan for the duration of the License. Licensee shall include in the

NLF O&M Plan submitted to the Commission documentation of approval by PADEP and the

Service, consultation with the other Resource Agencies, copies of the Resource Agencies’ 

comments and recommendations, and a description of how the other Resource Agencies’ 

comments are accommodated. Licensee shall provide a minimum of 30 days for review and 

approval of the NLF O&M Plan by PADEP and the Service and for review and comment by the 

other Resource Agencies.

Any amendment to the NLF O&M Plan that materially alters the operation, maintenance, 

monitoring or reporting procedures relating to the NLF Facility shall be subject to review and 

approval by PADEP and the Service, and review and comment by the other Resource Agencies.

Licensee shall provide copies of the approved NLF O&M Plan and all amendments thereto to the

Commission and the Resource Agencies.

9.9.3 Monitoring of Shad Passage Effectiveness & Subsequent Actions

The Licensee shall perform post-construction monitoring of the NLF Facility in accordance with 

the following provisions in consultation with the Resource Agencies and submit the results of 

such monitoring to the Resource Agencies and the Commission.

(a) The period from completion of construction through the end of the first American 

shad upstream shad passage season following completion of the NLF Facility will 

be a “shake-down” period, during which Licensee shall conduct visual 

observations and make adjustments to the NLF Facility to address any 
7

unanticipated inhibitions or barriers that impede the NLF Facility’s performance.

(b) Starting in the second American shad upstream passage season following 

completion of the NLF Facility, Licensee shall commence telemetry studies to 

monitor the overall effectiveness of the NLF Facility, consistent with the 

following:

(i) The telemetry studies will be conducted for at least two years, and potentially 

a third year if, after consultation with the Resource Agencies, determined to 

be necessary by the Licensee or either the Service or PADEP in order to 

obtain observations over a range of high and low flows typical of American 

shad passage seasons on the Susquehanna River. In general, the range 

defining typical high and low flows during the American shad upstream 

passage season would be anticipated to be as follows:

• Typical low flow range: 22,000 to 35,300 cfs.

• Typical high flow range: 35,300 cfs to 55,600 cfs.

(ii) The telemetry studies will be planned to be conducted during successive shad 

passage seasons, but may be performed on a non-successive basis under the 

following circumstances:

1. Licensee may postpone conduct of the telemetry studies, after consultation 

with the Resource Agencies and with the concurrence of the Service and 

PADEP, in the event that extenuating circumstances (such as the unusual 

flows, construction at downstream dams or other conditions) are interfering

or expected to interfere with upstream shad passage. The Resource

Agencies agree that in the event that they become aware of circumstances 

that would warrant postponement of the telemetry studies, they will 

promptly notify the Licensee, with the objective of providing notice to the

Licensee to the extent practicable at least 90 days prior to the anticipated 

start of the shad passage season.

2. Licensee may postpone a successive season’s telemetry study if Licensee 

determines, after consultation with the Resource Agencies and with the 

concurrence of Service and PADEP, that some physical adjustment to the 

NLF Facility is advisable based on the observations during the prior shad

passage seasons, in which case Licensee shall will implement the physical 

adjustments and perform the telemetry study in the American shad 

upstream passage season following implementation of the physical 

adjustment.

(iii) The telemetry studies will utilize American shad tagged at the Safe Harbor Project, 

provided that access is granted by the owner of such Project.

(iv) The telemetry studies shall utilize radio telemetry, acoustic telemetry, or such 

other technologies as Licensee proposes and PADEP and the Service, after 

consultation with the other Resource Agencies, approve. The general parameters 
8

and protocols for such telemetry studies (number of fish, fish release sites, target 

areas for telemetry antennas) are described in Appendix D. At least 10 months 

prior to the start of the second Upstream American Shad Passage Season following

completion of the NLF Facility, Licensee shall prepare and submit to the Resource

Agencies for review an NLF Facility Monitoring Plan (the “NLF Monitoring

Plan”) containing detailed protocols for the telemetry studies. Licensee shall 

confer with the Resource Agencies regarding the NLF Monitoring Plan, and shall 

provide for at least 90 days for PADEP and the Service to review and approve, and 

for the other Resource Agencies to review and comment on, the NLF Monitoring

Plan. At least five (5) months prior to the start of the second American shad 

upstream passage season following completion of the NLF Facility, Licensee shall 

submit the NLF Monitoring Plan to the Commission for approval. If Licensee does 

not adopt a recommendation made by a Resource Agency, the filing with the 

Commission shall include the Licensee’s reasons together with supporting 

information.

(c) Upstream American Shad Passage Target and Effectiveness Criteria:

(i) The target established by the Resource Agencies is for at least 75% of the 

upstream migrating American shad passing the Safe Harbor Dam to pass 

upstream of the Project through the combination of the NLF Facility and the East 

Channel Fishway (the “Upstream Shad Passage Target”).The NLF Facility shall 

be designed and operated to be capable of achieving the Upstream Shad Passage

Target, provided that adequate numbers of upstream migrating American shad

reach the Project Area.The Licensee shall not be deemed in violation of this 

condition if the Upstream Shad Passage Target is not achieved for reasons

beyond the reasonable control of the Project, provided that the Licensee complies 

with Sections 9.9.3(c)(ii)-(v) and (d)-(f) below.

(ii) The NLF Monitoring Plan will be designed to investigate several issues: (i) 

whether the upriver migrating American shad passing the Safe Harbor Dam are

reaching the Project Area; (ii) whether upriver migrating American Shad entering

the Project Area are attracted to the downstream entrance of the NLF Facility; and 

(iii) whether there are barriers to American shad entering into and passing through 

the NLF Facility (e.g., velocity barriers or other constraints).

(iii) The NLF Facility will be deemed to be effective if: (1) in two consecutive years 

after installation or subsequent modification of the NLF Facility, (A) the Upstream 

Shad Passage Target is achieved or (B) 85% of the tagged American shad that 

enter the Project Area exit the combination of the NLF Facility and the East 

Channel Fishway (the “Project Area Passage Success Criterion”); and (2) Licensee

complies with Section 9.9.3(d) below.

(iv) If the telemetry studies show that the Project Area Passage Success Criterion is 

achieved in two successive American shad upstream passage seasons which reflect 

a range of flows typical of shad passage seasons on the Susquehanna River, the

Project Area Passage Success Criterion will be deemed achieved and the Licensee

may terminate the telemetry studies.
9

(v) If the telemetry studies show that the Project Area Passage Success Criterion is 

not achieved in two successive American shad upstream passage seasons, and 

such failure was not due to unusual or extenuating circumstances (such as unusual 

flow or temperature conditions), the Licensee will undertake the actions set forth 

in Section 9.9.3(e) and then perform a telemetry study for at least two additional 

American shad upstream passage seasons to confirm achievement of the Project 

Area Passage Success Criterion.

(d) Licensee shall, in consultation with the Resource Agencies, evaluate the fish 

movement data from the NLF Monitoring Plan to determine if there are barriers to 

timely passage of upstream migrating American shad within the Project Area. If such 

barriers to timely passage of upstream migrating American shad are identified within 

the Project Area, Licensee shall prepare and submit to the Resource Agencies a plan 

and schedule for those actions to address such conditions that are feasible, appropriate

under the circumstances, reasonable and technically sound, provided that the Project 

shall not be required to undertake the curtailment of electric generating operations. 

Such plan shall be subject to review and approval by PADEP and the Service and 

review and comment by the other Resource Agencies. Following approval by PADEP

and the Service, and as necessary FERC, Licensee shall implement the approved plan 

in accordance with the approved schedule.

(e) If the Project Area Passage Success Criterion is not achieved, Licensee shall take the

following measures, as appropriate and necessary, after consultation with the 

Resource Agencies:

• Evaluate fishway hydraulics and access for velocity and shear stress 

barriers, recognizing that hydraulics of the NLF Facility will vary with 

river flow and flow through the NLF Facility.

• Adjust positions of rock weirs and attraction water discharge if necessary.

• Adjust timing of supplemental attraction flows.

• Install ultrasound to deter fish from an area (such as the Powerhouse or

East Channel).

• Reduce flows in the East Channel to reduce attraction of American shad to the

East Channel.

• Adjust amount of supplemental attraction flows in the NLF Facility up to the

Potential Increased Attraction Flow Value.

• Evaluate whether potential barriers exist in the channel downstream of the 

Main Dam hindering fish movement to the entrance of the NLF Facility, and if

reasonably necessary undertake feasible and cost-effective modifications to the

channel to remove such barriers.

(f) The upstream end of NLF Facility shall be designed to accommodate installation of

Passive Integrated Transponder (“PIT”) tag monitoring devices at such time as such 
10

PIT tag monitoring devices become available and feasible for reliably monitoring

American shad exiting the NLF Facility. At such time as requested by PADEP or the

Service, Licensee shall conduct a feasibility study to evaluate whether a PIT tag

monitoring facility can be successfully installed and maintained near the upper end of

the NLF Facility to reliably monitor American shad exiting the NLF Facility. Licensee

shall install PIT tag readers, or such other monitoring technology as may be agreed 

upon, after consultation with the Resource Agencies, by the Licensee, the Service and 

PADEP, at the upstream end of the NLF Facility when such technology becomes 

available, feasible, and technically sound for measuring American shad passage in the

conditions of the NLF Facility as mutually agreed to, after consultation with the

Resource Agencies, by Licensee, the Service and PADEP. The Parties contemplate

that such monitoring will use American shad tagged at Conowingo or Safe Harbor to 

monitor overall effectiveness of American shad upstream passage within the lower

Susquehanna River.

9.9.4 Upstream Passage of Eels

Licensee shall provide for upstream passage of juvenile American eels through maintenance of 

the existing Project and installation of the NLF Facility. Based upon their present understanding 

of the behavior of juvenile American eels and the design of the NLF Facility, the Service expects 

that the existing design of the Project in conjunction with the installation of the NLF Facility will 

be adequate to provide for successful upstream passage of juvenile American eels past the 

Project, and no other PM&E measures are presently believed to be necessary for such upstream 

passage of juvenile American eels.

9.9.5 Downstream Post-Spawning Adult American Shad Passage

(a) Licensee shall provide for downstream passage of post-spawning adult American 

shad through maintenance of the existing Project, installation and operation of the 

NLF Facility, and implementation of the protocol set forth in Section 9.9.5(b).

(b) During the period of May 1 to June 30, if River Flow exceeds the sum of Project 

Hydraulic Capacity, required flows through the NLF Facility, required flows 

through the East Channel, and required flows (if any) over the Main Dam, the 

Licensee will open and spill water via the Forebay Sluice Gate (~370 cfs) to the 

extent practicable during one to two hours during the morning during weekdays, 

subject to Project personnel availability and access requirements for operations 

and maintenance purposes. Such spilling may be provided in connection with 

opening of the Forebay Sluice Gate for purposes of passing debris, it being 

understood by the Parties that during the passage of debris, it will not be feasible 

to utilize the chute structure referenced in Section 9.9.6(e).

9.9.6 Downstream Juvenile American Shad Passage

(a) After issuance of the New License and until completion of the NLF Facility, 

Licensee shall implement the following protocol to facilitate downstream passage 

of juvenile American shad during the Downstream Juvenile American Shad 

Passage Period:
11

(i) During the entire Downstream Juvenile American Shad Passage Period, the 

Licensee will operate the Project units in the following order of priority, 

depending upon available River flow: (1) Unit 1-6 (Propeller units) may be

operated without restriction up to available river flow; (2) Unit 14 (larger 

single Francis unit) may be operated if river flow exceeds capacity of Units 1-

6; (3) Units 7-13 and 15-30 (double Francis units) may be operated in 

ascending order if river flow exceeds capacity of Unit 1-6 and 14.

(ii) During the entire Downstream Juvenile American Shad Passage Period, the 

Licensee will open and spill water via the forebay sluice gate (~ 370 cfs) 

between the hours of 5 pm to 11 pm Eastern Standard Time (“EST”).

210

(iii) If River flow exceeds the sum of Project Hydraulic Capacity, required flows 

through the East Channel, and required flows (if any) over the Main Dam, the 

Licensee will open and spill water via the forebay sluice gate (~370 cfs) to the 

extent practicable for one to two hours during the morning, subject to Project 

access requirements for operations and maintenance purposes, in order to 

provide for downstream juvenile American shad passage.

(b) After completion of the NLF Facility, Licensee shall implement the following 

protocol to facilitate downstream passage of juvenile American shad during the 

Downstream Juvenile American Shad Passage Period:

(i) During the entire Downstream Juvenile American Shad Passage Period, the 

Licensee will operate the Project units in the following order of priority, 

depending upon available River flow: (1) Unit 1-6 may be operated without 

restriction up to available river flow); (2) Unit 14 may be operated if river 

flow exceeds capacity of Units 1-6; (3) Units 7-13 and 15-30 may be operated 

in ascending order if river flow exceeds capacity of Unit 1-6 and 14.

(ii) During the entire Downstream Juvenile American Shad Passage Period, the 

Licensee will open and spill water via the forebay sluice gate (~ 370 cfs) 

between the hours of 5 pm to 11 pm EST.

(iii) The NLF Facility will be operated to maintain a flow through the fishway of 

approximately 200 cfs.

(iv) If river flow exceeds the sum of Project Hydraulic Capacity, required flows 

through the NLF Facility, required flows through the East Channel, and 

required flows (if any) over the Main Dam, the Licensee will open and spill 

water via the forebay sluice gate (~370 cfs) to the extent practicable for one to 

two hours during the morning, subject to Project access requirements for 

 2 Note: During the Downstream Juvenile American Shad Passage Season, a portion of the period is 

in daylight savings time and a portion is in standard time. All timeframes stated in this Offer of 

Settlement are stated in Eastern Standard Time. During October, sunset in the central Pennsylvania 

area is in a range of 5:50-5:05 pm EST. During November, sunset in central Pennsylvania occurs in 

a range of 5:05 pm to 4:42 pm EST.
12

operations and maintenance purposes, in order to provide for downstream 

juvenile American shad passage.

(c) The overall goal for juvenile American shad downstream passage is to achieve 

survival of 95% of juvenile American shad from above the Project powerhouse 

and dam to below the Project powerhouse and dam (the “Downstream Juvenile 

American Shad Passage Goal”). Measurement of such passage effectiveness and 

survival is subject to a margin of error. The effectiveness of downstream passage 

operations for juvenile American shad will be determined based upon (1) a route

of passage analysis as described in Section 9.9.6(d), and (2) confirmation that

Forebay Sluice Gate provides for safe passage as described in Section 9.9.6(e).

(d) For purposes of the route of passage analysis, the Service will assume that (1) 

juvenile American shad will pass through the NLF Facility, through the East 

Channel past the East Channel Dam, over the Main Dam, and into the head race in 

direct proportion to the amount of flow via each such route; (2) any juvenile 

American shad passing through the NLF Facility, through the East Channel past the

East Channel Dam, over the Main Dam, or through the forebay sluice gate will 

survive; (3) juvenile American shad that do not pass through the NLF Facility, 

through the East Channel past the East Channel Dam, over the Main Dam, or

through the forebay sluice gate will pass through the turbines that are being operated 

in accordance with the priorities set forth in Section 9.9.6(b), and absent observations 

to the contrary, are allocated between the operating turbines

in proportion to the flow through each turbine; and (4) the survival rate of juvenile 

American shad passing through individual turbines (based on previous balloon tag and 

blade strike analyses) are as stated in Appendix D. Based upon the foregoing 

assumptions and confirmation that Forebay Sluice Gate provides for safe passage as 

described in Section 9.9.6(f), the juvenile American shad passage goal of 95% would 

be met if at least 60% of the tagged juvenile American shad released into the headrace

exit via the Forebay Sluice Gate (that is, pass downstream of the Project headrace

without passing through the turbines) (the “Headrace Shad Turbine Avoidance

Target”). Licensee shall test the downstream passage efficiency of the operating

protocols described above by a PIT tag monitoring study. Licensee shall, in

consultation with the Resource Agencies, prepare a plan and schedule for the Headrace

Shad Turbine Avoidance Study for review and approval of the Resource Agencies, 

consistent with the design criteria set forth in Appendix D. The Project will be

deemed to meet the Downstream Juvenile American Shad Passage Goal if (1) the

Headrace Shad Turbine Avoidance Study shows that the Headrace Shad Turbine

Avoidance Target is achieved and (2) the Licensee complies with the provisions of

Section 9.9.6(f) to establish conditions under which the Forebay Sluice Gate provides 

for safe passage of juvenile American shad.

(e) Within four (4) years following License issuance and prior to performance of the 

downstream juvenile American shad studies referenced in Section 9.9.6(d), License

shall prepare and submit to the Resource Agencies: (i) designs for a chute structure to 

convey flows beyond the roadway on the downstream side of the Cable Alley

structure, meeting the design criteria set forth in Appendix E

allowing juvenile and adult American shad to land unimpeded in the downstream pool; 
13

and (ii) removal of obstructions in or deepening of the downstream pool into which 

flows from the Forebay Sluice Gate land to provide an adequate depth of 1 foot for

each 4 feet of drop into which juvenile or adult American shad may land. Licensee

shall submit any design plans for improvements as described in this Section 9.9.6(e)

and a proposed implementation schedule to the Service and PADEP for review and 

approval and to the other Resource Agencies for review and comment, and shall 

implement the proposed improvements in accordance

with the approved designs and schedule. Any such required improvements shall be

completed coincident with completion of the NLF Facility, and in advance of 

commencement of the monitoring described in Section 9.9.6(d) .

(f) If the effectiveness monitoring conducted pursuant to Section 9.9.6(d) shows that the

Headrace Shad Turbine Avoidance Target is not achieved, Licensee shall implement 

the following sequence of adaptive measures in the next passage season:

(i) Open the NLF supplemental flow gate (800 cfs) during the same schedule as the

Forebay Sluice Gate is opened.

(ii) Suspend operation of certain Francis turbine units during the hours of 5-11 pm 

EST when river flows are between 15,000 cfs and 22,000 cfs during the 

Downstream Juvenile American Shad Passage Period, up to a total generation loss 

of 1,000 Megawatt hours (“MWh”).

(iii) Such other measures as may be agreed to by the Licensee, the Service and 

PADEP, after consultation with the other Resource Agencies, and (to the extent 

required) approved by the Commission.

(g) Within two years of implementing the adaptive measures referenced in Section

9.9.6(f), Licensee shall conduct a follow-up Headrace Shad Turbine Avoidance 

Study following the protocols referenced in Section 9.9.6(d) . If the follow-up 

Headrace Shad Turbine Avoidance Study shows that Headrace Shad Turbine 

Avoidance Target is achieved, such adaptive measures shall continue to be 

implemented for the duration of the License.

(h) If by January 1, 2028, (a) the Headrace Shad Turbine Avoidance Studies have not 

shown that Headrace Shad Turbine Avoidance Target is being achieved by adaptive

measures implemented at the Project, and (b) based on all available information and 

after consultation with Licensee and the other Resource Agencies, the Service renders 

a determination on the basis of the record reasonably finding that (i) Licensee has not 

demonstrated that the adaptive measures implemented at the Project are reasonably

anticipated to meet the Downstream Juvenile American Shad Passage Goal, and (ii)

additional measures that are reasonably required to achieve the Downstream Juvenile

American Shad Passage Goal (the “Additional Measures Determination”) (which

Additional Measures Determination shall be subject to the dispute resolution / appeal 

procedures set forth in the Settlement):

(i) Within 12 months of the Additional Measures Determination, Licensee shall, in 

consultation with the Resource Agencies, prepare a design and schedule for 

implementation of additional structural and operational measures reasonably 
14

anticipated to meet the Downstream Juvenile American Shad Passage Goal that are

feasible, appropriate under the circumstances, reasonable and technically sound. 

Licensee shall evaluate, among other options, options for a Fish Guidance System 

(“FGS”) as described in the report entitled Evaluation of Fish Guidance Systems 

(Draft April 2013), or other appropriate technology to achieve the Downstream 

juvenile American shad Passage Goal. As part of the evaluation report, Licensee

shall provide sufficient information to demonstrate the reasonably likelihood of the

proposed option and measures to meet the Downstream Juvenile American Shad 

Passage Goal.

(ii) Following approval of the design and schedule by the Service and PADEP, 

after consultation with the other Resource Agencies, Licensee shall prepare 

and submit the applications for all required governmental approvals, including 

FERC approvals, and procure, install and implement the approved structural 

and/or operational measures in accordance with the approved schedule. Such 

approved measures shall be implemented by December 31, 2030 or such other 

date as agreed to by Licensee and the Service, after consultation with the other 

Resource Agencies, or as approved by FERC.

(iii) If Licensee does not present a design and schedule for implementing 

additional structural and operational measures reasonably anticipated to meet 

the Downstream Juvenile American Shad Passage Goal that are feasible, 

appropriate under the circumstances, reasonable and technically sound, or 

based on all available information and after consultation with Licensee and 

the Resource Agencies, the Service does not approve the Licensee’s design 

and schedule for additional measures submitted pursuant to Section

9.9.6(h)(i), the Service may elect to exercise its reserved authority to 

prescribe such measures as the Service determines are necessary for safe and 

effective passage of downstream migrating American shad; and Licensee 

retains all rights to challenge any such exercise of reserved authority.

(i) Within one year after the implementation of the structural and operational 

measures implemented under Section 9.9.6(h), Licensee shall perform a follow-up 

Headrace Shad Turbine Avoidance Study to evaluate the number of tagged 

juvenile American shad that exit the Forebay without exposure to the turbines.

9.9.7 Downstream Passage for Silver Eels

Licensee shall provide for the downstream passage of silver eels in accordance with this Section.

(a) The overall goal for silver American eel passage shall be to achieve effective 

passage and survival of 85% of silver eels from above the Project dams and 

powerhouse to below the Project dams and powerhouse (the “Downstream Eel 

Passage Goal”). Measurement of such passage effectiveness and survival is 

subject to a margin of error.

(b) Licensee shall cooperate with the Resource Agencies and other interested parties 

in the conduct of (1) a Lower Susquehanna River Downstream Eel Study to 

evaluate the timing, magnitude, duration, annual variation and environmental 
15

conditions associated with active migration of silver eels from tributaries stocked 

with elvers, through the lower Susquehanna River to the Chesapeake Bay; and (2) 

a Site-Specific Route of Passage Study to evaluate the route of passage selected 

migrating silver eels in the vicinity of the Project. The design criteria for the

Lower Susquehanna River Downstream Eel Study and the Site-Specific Route of

Passage Study are described in Appendix G.

(c) At least 12 months prior to the anticipated date for completion of the NLF Facility, 

in consultation with the Resource Agencies, Licensee shall prepare a plan and 

schedule for conducting a discrete downstream passage effectiveness study (“SiteSpecific Downstream Eel Study”), consisting of a Site Specific Route of Passage

Study as described in Appendix G and an Eel Survival Study as described in 

Appendix H. Licensee shall submit the Site-Specific Downstream Eel Study plan 

and proposed schedule to the Resource Agencies, for review and approval by the

Service and PADEP and for review and comment by the other Resource Agencies. 

Licensee, in cooperation with the Resource Agencies, shall conduct the SiteSpecific Route of Passage Study following completion of the NLF Facility in

accordance with the approved plan and schedule, and Licensee shall conduct the

Eel Survival Study in accordance with the approved plan and schedule.

(d) If the results of the Site-Specific Downstream Eel Passage Study indicate that the 

then existing Project operating measures and protocols achieve the Downstream Eel 

Passage Goal, then the Licensee shall continue to implement those protocols and 

measures.

(e) If the results of the Site-Specific Downstream Eel Passage Study do not indicate that 

the Project’s existing operating measures and protocols do not achieve the 

Downstream Eel Passage Goal, the Licensee will prepare and submit to the Resource

Agencies a plan and schedule for evaluating the feasibility and costs of potential 

physical and/or operational modifications to the Project to facilitate downstream eel 

passage (the Downstream Eel Improvements Study). The Downstream Eel

Improvements Study plan and schedule shall be subject to review and approval by

PADEP and the Service and review and comment by the other Resource Agencies.

Licensee shall conduct the Downstream Eel Improvements Study in accordance with 

the approved plan and schedule. The Downstream Eel Improvements Study will 

consider and evaluate whether any of the following adaptive measures to facilitate

downstream eel passage, which may be implemented in a sequence or in combination, 

are feasible, appropriate under the circumstances, reasonable and technically sound 

and are reasonably expected to contribute toward achievement of the Downstream Eel 

Passage Goal:

(i) Adjustment to NLF Facility operations. (ii)

Installation of current inducers.

(iii)Modifications to the juvenile American shad protection measure. 

(iv)Installation of a fish guidance system.

(v) Replacement of turbine runner systems with units designed to have a lower 

mortality impact upon silver eels.
16

(vi)Other measures mutually agreed to by the Licensee, the Service and PADEP, 

after consultation with the other Resource Agencies.

(f) If the Downstream Eel Improvements Study identifies physical or operational 

adaptive measures listed in Section 9.9.7(e) to facilitate downstream eel passage that 

are feasible, appropriate under the circumstances, reasonable and technically sound, 

Licensee shall prepare a plan and schedule for implementing such measures and an 

estimation as to the ability of such measures to achieve the Downstream Eel Passage

Goal, and will submit the plan and schedule to the Resources Agencies for review and

approval by the Service and PADEP and review and comment by the other Resource

Agencies. Following approval of such plan and schedule, Licensee shall implement 

the measures described in the approved plan in accordance with the approval 

schedule. If Licensee does not present such a plan and schedule for implementing

physical or operational adaptive measures listed in Section 9.9.7(e) that are feasible,

appropriate under the circumstances, reasonable and technically sound, and 

reasonably anticipated to meet the Downstream Eel Passage Goal, or based on all 

available information and after consultation with Licensee and the Resource

Agencies, the Service does not approve the Licensee’s plan and schedule for such 

measures submitted pursuant to this Section, the Service may elect to exercise its 

reserved authority to prescribe such measures as the Service determines are necessary

for safe and effective passage of downstream migrating American eel; and Licensee

retains all rights to challenge any such exercise of reserved authority.

(g) Within 12 months following implementation of any such improvements, Licensee 

shall evaluate and provide a report to the Resource Agencies regarding the 

effectiveness of the measures in relation to achievement of the Downstream Eel 

Passage Goal.

(h) If the adaptive measures implemented pursuant to the Downstream Eel Improvements 

Study do not result in achievement of the Downstream Eel Passage Goal, the

Licensee and the Resource Agencies shall on an annual basis consult as to potential 

additional studies or adaptive measures that are or may become feasible, appropriate

under the circumstances, reasonable and technically sound, and reasonably expected

to contribute toward achievement of the Downstream Eel Passage Goal.

10. Scientific Names

American eel (Anguilla rostrata) 

American shad (Alosa sapidissima) 

Alewife (Alosa pseudoharengus) 

Blueback herring (Alosa aestivalis) 

Hickory shad (Alosa mediocris)

Shortnose sturgeon (Acipenser brevirostrum) 

Atlantic sturgeon (Acipenser oxyrinchus) 

Striped bass (Morone saxatilis)
APPENDIX E

Preliminary Fishway Prescription – Muddy Run Pumped Storage Project
35

FISH PASSAGE 

A. General Requirements

1. Fish Passage Operating Procedures (“FPOP”)

a. By January 15, 2015, EXELON shall submit a FPOP to the DEP 

for review and approval. The FPOP will describe existing baseline 

operations during fish passage season, including schedules for 

routine maintenance, procedures for routine operation (including: 

seasonal and daily periods of operation, pump and turbine 

operations), sequencing of pump and turbine start-up and 

operation, procedures for monitoring and reporting flows, 

procedures for monitoring and reporting on the operation of the 

facility, procedures for start-up and shut-down, and procedures for 

use in case of emergencies and project outages significantly 

affecting the conditions of this certification.

b. EXELON shall implement the FPOP consistent with the approval 

of the DEP. EXELON shall provide written documentation to the 

Resource Agencies that operational personnel have reviewed and 

understand the FPOP signed by the operations manager of the 

Project.

c. Copies of the approved FPOP and all modifications will be 

provided to the Resource Agencies.

d. By December 31 of each year, EXELON shall provide an annual 

report to the Resource Agencies detailing: the implementation of 

the FPOP, including any deviations from the FPOP and a process 

to prevent those deviations in the future; any proposed 

modifications to the FPOP, or in the case of emergencies or project 

outages, the steps taken by EXELON to minimize adverse effects 

on fisheries including any proposed modifications to those steps to 

further enhance their effectiveness in the future. EXELON shall 

offer to meet with the Resource Agencies by January 31 of each 

year unless a different date is mutually agreed upon by EXELON 

and the Resource Agencies. Any required modifications to the 

FPOP shall be submitted to the Resource Agencies within 45 days 

of receipt of a request for the modification unless a longer period is 

approved by the DEP. The modifications to the FPOP shall be 

implemented consistent with the approval of the DEP. In the 

event EXELON fails to submit the modifications as required by 

this paragraph, the DEP, in consultation with the other Resource 

Agencies, may establish modifications and EXELON shall 
36

implement the modifications consistent with the approval of the 

DEP.

B. American Shad Passage

1. Upstream Shad Passage

a. Cooperation with Holtwood. If the Holtwood Hydroelectric 

Facility fails to meet its Tier I upstream shad passage target 

described and included in the 401 Water Quality Certification for 

the Amended Holtwood Hydroelectric Facility, and DEP

determines that EXELON’s operation of the Muddy Run Project is 

a proximate cause of Holtwood failing to meet the Tier 1 target, 

EXELON shall meet with the Resource Agencies to establish and 

implement a plan and schedule for a radio telemetry study or 

equivalent (Tier II Study) of American shad passage and behavior 

within the Muddy Run project boundary. This meeting shall occur 

within one month of the DEP’s determination that Holtwood failed 

to meet its Tier 1 upstream shad passage target or such longer time 

as established by the DEP in writing.

 

b. Evaluation of Muddy Run Shad Passage. If EXELON is a 

proximate cause of Holtwood’s failure to meet its Tier I upstream 

shad passage target, EXELON shall develop a radio telemetry 

study plan and schedule or equivalent to determine: (1) the 

percentage of American shad that enter Muddy Run project at the 

northern tip of Sicily Island area and subsequently exit the Muddy 

Run project area at the southern tip of Deepwater Island; and (2) 

any delay or impedance of shad passage attributable to the 

redevelopment of the Holtwood Facility. EXELON shall 

coordinate development of this plan with the Holtwood 

Hydroelectric Facility and the Conowingo Hydroelectric Facility. 

The radio telemetry study shall be designed to insert the transmitter 

at the Conowingo facility or at such other location(s) approved by 

the DEP.

 

c. Within two months of the meeting described in Paragraph 

III.B.1.a. or such longer period approved by the DEP in writing, 

EXELON shall submit the fish passage study plan and schedule to 

the Resource Agencies for review and approval by DEP. 

EXELON shall implement the plan according to the schedule 

therein and consistent with the approval of the DEP. In the event 

EXELON fails to submit the plan and schedule as required by this 

paragraph, the DEP, in consultation with the other Resource 

Agencies, may establish a plan and schedule and EXELON shall 
37

implement that plan and schedule consistent with the approval of 

the DEP. EXELON shall continue implementation of fish passage 

study for a minimum of four years or such other time period as 

required by the DEP in consultation with the other Resource 

Agencies. EXELON shall provide an annual report of the 

monitoring results of fish passage study by December 31st of each 

year.

d. At the end of the four-year study period, or such longer time as 

established by the DEP, if the results indicate that, as a result of 

Muddy Run operations, less than 88% of the American shad that 

enter the Muddy Run project waters at the northern tip of Sicily 

Island exit the Muddy Run project waters at the southern tip of 

Deepwater Island, EXELON shall propose a plan and schedule for 

operational modifications to enhance fish passage at the project. 

EXELON shall not be responsible for mitigating any impacts 

attributable to PPL Holtwood. This plan and schedule shall be 

submitted to the DEP as an amendment to the FPOP for the 

following year. EXELON shall implement the plan and schedule 

consistent with the approval of the DEP. In the event EXELON

fails to submit the plan and schedule as required by this paragraph, 

the DEP, in consultation with the other Resource Agencies, may 

establish a plan and schedule and EXELON shall implement that 

plan and schedule consistent with the approval of the DEP.

e. The average of the two highest years in the monitoring period will 

be used determine whether the 88% fish passage percentage is 

achieved. If EXELON implements operational modifications, only 

those years following the operational modifications shall be 

considered to determine whether the 88% passage percentage is 

achieved.

f. If at the end of the monitoring period, or such longer time as 

established by the DEP, the results indicate that the operational 

modifications have resulted in less than 88% of the American shad 

that enter the Muddy Run project waters pass through the Project, 

EXELON shall propose a plan and schedule for mitigation, as 

defined in 25 Pa. Code Section 105.1 for the failure to achieve the 

88% fish passage target. This mitigation shall be: (1) in addition to 

the compensatory mitigation described in this certification; and (2) 

reasonably related and proportional to the identified impact. This 

plan and schedule shall be submitted to the Resource Agencies 

within 6 months from the end of the monitoring period. EXELON 

shall implement the plan and schedule consistent with the approval 

of the DEP. In the event EXELON fails to submit the plan and 
38

schedule as required by this paragraph, the DEP, in consultation 

with the other Resource Agencies, may establish a plan and 

schedule and EXELON shall implement that plan and schedule 

consistent with the approval of the DEP.

2. Downstream Shad Passage

a. Consistent with the relicensing studies for Muddy Run, by January 

15, 2015, EXELON shall submit a plan and schedule to provide for 

95% survival of the juvenile American shad and 80% survival of 

the adult American shad that pass through the project area. The 

schedule shall provide for full implementation of the plan by 2015. 

EXELON shall implement the approved plan and schedule. If 

EXELON fails to submit the plan, the DEP shall develop a plan 

and schedule, in consultation with the other resource agencies, and 

EXELON shall implement that plan and schedule.

b. By February 15, 2026 or such later date approved by the DEP in 

writing, EXELON shall submit a plan to measure the passage of 

American shad moving downstream past the project to the DEP for 

approval (“Discrete Passage Study”). EXELON shall implement 

the plan to measure the passage of American shad moving 

downstream past the project according to the schedule and 

consistent with the approval of the DEP (“Discrete Passage 

Study”). In the event EXELON fails to submit the plan and 

schedule required by this paragraph, the DEP, in consultation with 

the other Resource Agencies, may establish a plan and schedule 

and EXELON shall implement that plan and schedule consistent 

with the approval of the DEP.

c. EXELON shall, in accordance with the plan, conduct the Discrete 

Passage Study. EXELON shall provide a report of the Discrete 

Passage Study within 180 days of its completion or such later date 

approved by the DEP in writing to the Resource Agencies.

d. If the results of the Discrete Passage Study indicate that EXELON 

can operate the Muddy Run project so that EXELON achieves at 

least 95% passage of the juvenile American shad and 80 % passage 

of the adult American shad that pass through the project area based 

on the likelihood of a shad being exposed to typical pumping 

operations and becoming entrained, then EXELON shall 

incorporate into the annual FPOP any required operational 

measures or protocols to meet the established percentages. These 

procedures will be subject to review at the annual meeting for the 

FPOP.
39

e. If the results of the Discrete Passage Study do not indicate that the 

project can be operated to achieve at least 95% passage of juvenile 

American shad and 80% passage of adult American shad based on 

the likelihood of a shad being exposed to typical pumping 

operations and becoming entrained, EXELON shall propose a plan

and schedule for mitigation, as defined in 25 Pa. Code Section 

105.1, for the failure to achieve the fish passage target or targets. 

This mitigation shall be: (1) in addition to the compensatory 

mitigation described in this certification; and (2) reasonably related 

and proportional to the identified impact. This plan and schedule 

shall be submitted to the Resource Agencies within 6 months from 

the end of the monitoring period or such later date approved by the 

DEP in writing. EXELON shall implement the plan and schedule 

consistent with the approval of the DEP. In the event EXELON 

fails to submit the plan and schedule as required by this paragraph, 

the DEP, in consultation with the other Resource Agencies, may 

establish a plan and schedule and EXELON shall implement that 

plan and schedule consistent with the approval of the DEP.

C. Eel Passage

1. Upstream Eel Passage

The terms and conditions of the EXELON Generation American Eel Passage 

Plan for the Muddy Run Pumped Storage Hydroelectric Project (P-2355), 

attached hereto as Appendix 1 (Appendix 3 of the Department’s Fish Pasage

Prescription), are incorporated as if fully set forth herein.

2. Downstream Eel Passage

a. The trigger date for initiation of downstream eel passage studies 

shall be the date on which the DEP, in consultation with the other 

Resource Agencies, determines that available data indicates that 

eels are present upstream of the project or other upstream areas in 

numbers appropriate to require downstream eel passage. This 

trigger date shall not occur prior to October 1, 2026 in order for the 

trapping and transport program to have sufficient time to 

reestablish a significant eel population.

b. EXELON shall achieve at least 85% eel passage through the 

project area based on the likelihood of an American eel being 

exposed to typical pumping operations and becoming entrained. 

c. Within six months of the trigger date in Paragraph (a), or such later 

date approved by the DEP in writing, EXELON shall submit a plan 
40

to conduct a passage study to the Resource Agencies. The plan 

shall be designed to demonstrate continued compliance with the 85 

% fish passage target. The plan shall include radio telemetry 

studies or such other studies approved by the DEP in consultation

with the other Resource Agencies. EXELON shall implement the 

plan according to the schedule consistent with the approval of the 

DEP. In the event EXELON fails to submit the plan and schedule 

as required by this paragraph, the DEP, in consultation with the 

other Resource Agencies, may establish a plan and schedule and 

EXELON shall implement that plan and schedule consistent with 

the approval of the DEP. 

d. The study shall be initiated within 1 year of the trigger date unless 

a different time frame is approved by the DEP in writing. 

EXELON shall provide a report of the study results within 180 

days of the date of completion of the study. 

e. If the results of a discrete passage study indicate that EXELON can 

operate the project so that EXELON achieves at least 85% passage 

of the American eel that pass through the project area based on the 

likelihood of an American eel being exposed to typical pumping 

operations and becoming entrained, EXELON shall incorporate 

into the FPOP any operational measures needed to meet this 

percentage. These procedures will be subject to review at the 

annual FPOP meeting.

f. If the results of the studies do not indicate that the project can be 

operated to achieve at least 85% passage of American eel based on 

the likelihood of an American eel being exposed to typical 

pumping operations and becoming entrained, EXELON shall 

propose a plan and schedule for mitigation, as defined in 25 PA. 

Code Section 105.1, for the failure to achieve the 85% eel passage 

target. This mitigation shall be: (1) in addition to the 

compensatory mitigation described in this certification; and (2) 

reasonably related and proportional to the identified impact. This 

plan and schedule shall be submitted to the Resource Agencies 

within 6 months from the end of the monitoring period or such 

later date approved by the DEP in writing. EXELON shall 

implement the plan and schedule consistent with the approval of 

the DEP. In the event EXELON fails to submit the plan and 

schedule as required by this paragraph, the DEP, in consultation 

with the other Resource Agencies, may establish a plan and 

schedule and EXELON shall implement that plan and schedule 

consistent with the approval of the DEP.

Reservation of Authority to Prescribe Fishways

In order to allow for the timely implementation of fishways, including effectiveness measures, 

the Department proposes to reserve its authority by requesting that the Commission include the 
41

following condition in any license it may issue for the Project: 

Pursuant to section 18 of the Federal Power Act, the Secretary of the Interior herein 

exercises her authority under said Act by reserving that authority to prescribe fishways 

during the term of this license and by prescribing the fishways described in the Department 

of the Interior’s Prescription for Fishways at the Muddy Run Project.

Preliminary Prescription for Fishways

Pursuant to section 18 of the Federal Power Act, as amended, the Secretary of the Department of 

the Interior, as delegated to the Service, proposes to exercise her authority to prescribe the 

construction, operation and maintenance of such fish passage facilities and measures as deemed 

necessary, subject to the procedural provisions contained above.

The Department’s Preliminary Prescription for Fishways reflects a number of issues and 

concerns related to fish restoration and passage that have been raised by the applicant, 

Commission staff, State resource agencies, and other parties involved in these proceedings. 

Fish passage facilities and or measures shall be constructed, operated, and maintained to provide 

safe, timely and effective passage for American shad, alewife, blueback herring, American eels 

and other designated resident riverine fish species at the licensee's expense. 

To ensure the immediate and timely contribution of the fish passage facilities and measures to 

the ongoing and planned anadromous and catadromous fish restoration and enhancement 

program in the Susquehanna River, the following are included and shall be incorporated by the 

Licensee to ensure the effectiveness of the fishways pursuant to section 1701(b) of the 1992 

National Energy Policy Act (P.L. 102-486, Title XVII, 106 Stat. 3008). 

Fish Passage Requirements

Design Populations

American Shad

The design population at the Project for American shad is derived from the 1993 Settlement 

Agreement for the Development of Fish Passage Facilities at the Holtwood, Safe Harbor, and 

York Haven Projects on the Susquehanna River36

 36 Settlement Agreement. June 1, 1993. Pennsylvania Power & Light Company, Safe Harbor 

Water Power Corporation, and York Haven Power Company, AND U.S. Fish and Wildlife 

Service – U.S. Department of the Interior, Pennsylvania Fish and Boat Commission, 

Pennsylvania Department of Environmental Resources, Maryland Department of Natural 

Resources, Susquehanna River Basin Commission, Upper Chesapeake Watershed Association, 

and Pennsylvania Federation of Sportsmen's Clubs.

. Pursuant to that agreement the existing 

fishway at the Holtwood Dam immediately upstream of the Muddy Run Project was designed to 

pass 2,700,000 American shad. That same number of shad is the design population for the 
42

Muddy Run Project, as there is no spawning habitat between the two dams, and all fish need to 

continue migration upstream past Muddy Run Project to account for any migration fallout while 

attempting to pass through upstream hydroelectric projects.

Delays to upstream migration of American shad at hydroelectric facilities can compromise their 

ability to successfully spawn37 through increasing energetic costs and causing a mismatch 

between when shad arrive in suitable spawning habitat and optimal temperatures for spawning. 

The Service developed a model to evaluate how rates of upstream shad migration (proportion of 

shad passed in a given number of hours) in the Susquehanna River affect the timing of when 

shad arrive in suitable spawning habitat upstream of York Haven Dam relative to optimal 

temperatures for spawning. Shad that reached areas above York Haven Dam prior to a time when 

temperatures would exceed those that are optimal for spawning were considered to have 

successful migrations.

The model estimated 97% of shad had successful migrations if there were no impediments 

(delays) to migration. As the number of hours to pass shad increased at each hydroelectric 

facility, successful migration approached 0% when delay times at a given facility reached 168 

hours (7 days). The rate of passage in terms of percentage passed per time is also an important 

factor when determining the impact of migratory delays (USFWS 2013c). To minimize the 

impact of migratory delays on spawning success for migrating adult American shad, the Service 

is requiring successful passage of 80% of adult American shad at each project within 36 hours of 

arrival to the Project in addition to the SRAFRC Management Plan (2010) requirement of 85% 

overall upstream passage effectiveness for adult American shad38.

Therefore American shad passage at Muddy Run Project shall be adequate (target number passed 

with minimal delay) so as not to interfere with passage objectives and targets established for the 

Susquehanna River. If fish passage monitoring require in this prescription indicates that 

American shad are not meeting the target passage of 80% of adult American shad at each project 

within 36 hours at the Muddy Run Project the licensee will need to consult with the Service 

regarding development of a plan for implementation of project operational measures and/or 

construction of facilities that will meet the passage target.

River Herring (Alewife and Blueback Herring)

The design population at the Project for river herring is derived from the 1993 Settlement 

Agreement for the Development of Fish Passage Facilities at the Holtwood, Safe Harbor, and 

York Haven Projects on the Susquehanna River, and the existing fishway at Holtwood was 

designed to pass 10,00,000 river herring.

As such river herring passage at Muddy Run Project shall be adequate so as not to interfere with 

passage objectives and targets at the Holtwood Hydroelectric Project immediately upstream of 

 37 Federal Energy Regulatory Commission, Division of Hydropower Administration and 

Compliance, Office of Energy Projects, 2004. Evaluation of Mitigation Effectiveness at 

Hydroelectric Projects: Fish Passage. September 2004.

38 Id at 32.
43

the Muddy Run Project, or the Conowingo Hydroelectric immediately downstream of the Muddy 

Run Project.

American Eel

American eel do not currently have access to Project waters due to a lack of upstream passage at 

the Conowingo Hydroelectric Project located downstream, but the Department anticipates that 

passage to the Muddy Run Project area for juvenile eels will shortly become available through 

passage past the Conowingo Hydroelectric Project for migrating eels. While the Department 

does not have a precise estimate of the numbers of eels that would be expected to pass through 

the Muddy Run Project area, measures to achieve safe, timely and effective passage past the 

Muddy Run Project would enhance the eel stocks and help achieve overall management goals of 

federal and state resource agencies.

As such American eel passage at Muddy Run Project shall be adequate so as not to interfere with 

passage objectives at the Holtwood Hydroelectric Project immediately upstream of the Muddy 

Run Project, or the Conowingo Hydroelectric immediately downstream of the Muddy Run 

Project. The American Eel Restoration Plan for the Susquehanna River Basin (SRAFRC 2013)

states that all available eel seeking passage at a hydroelectric project be passed upstream (i.e. no 

impact), and that there be 85% downstream passage survival at each hydroelectric project.
44

Fish Passage Operating Periods

Regarding the timing of seasonal fish passage operations, fish passage facilities and measures

shall be maintained and operated, at the licensee's expense, to maximize fish passage 

effectiveness throughout the upstream and downstream migration periods for American shad, 

alewife, blueback herring, American eel, and designated riverine fish. 

Table 13: Upstream and downstream migration periods for species covered in this Prescription 

for Fishways. *

Species Upstream Migration Period Downstream Migration 

Period

American shad April 1 through June 15 July 1 through November 15 

(juv.)

April 15 through July 1 (adult)

Alewife & Blueback herring March 1** through June 15 June 15 through October 14 

(juv.)

April 15 through July 1 (adult)

American eel May 1 through September

15***

September 15–February 15,

whenever river temperature is

above 37 degrees F ****

* Any of these migration periods may be changed during the term of the license by the 

Department, based on new information, and in consultation with the other fishery agencies and 

the licensee.

** This operational period is based on preliminary data on Alewife migration timing from other 

tributaries to the Chesapeake Bay (Sutherland 2000, Eyler et al. 2002, Slacum 2003).

***This initial operational period is based on preliminary data on American eel migration timing 

from other tributaries to the Chesapeake Bay.

**** The Department is requiring the licensee to study the magnitude and timing of downstream 

eel migration through the project so that the effectiveness of the reduced period can be evaluated. 

This initial operational period is based on preliminary data on American eel migration timing 

from other tributaries to the Chesapeake Bay (Welsh et al. 2009).
45

Fish Passage Operating Procedures 

The timely and proper implementation of the fish passage measures is necessary to ensure the 

effectiveness of such measures. Therefore, the Department's Prescription includes the express 

requirement that the licensee develop Fish Passage Operating Procedures (FPOP) for 

implementation of operational measures during the migratory fish passage season. 

By January 15, 2015, the licensee shall submit a FPOP to the Department for review and 

approval. The FPOP will describe prescribed baseline operations during fish passage season, 

including schedules for routine maintenance, procedures for routine operation (including: 

seasonal and daily periods of operation, pump and turbine operations), sequencing of pump and 

turbine start-up and operation, procedures for monitoring and reporting flows, procedures for 

monitoring and reporting on the operation of the facility, procedures for start-up and shut-down, 

and procedures for use in case of emergencies and project outages significantly affecting the 

conditions of this prescription.

The licensee shall implement the FPOP consistent with the approval of the Department. The 

licensee shall provide written documentation to the Resource Agencies that operational 

personnel have reviewed and understand the FPOP signed by the operations manager of the 

Muddy Run Project.

Copies of the approved FPOP and all modifications will be provided to the Resource Agencies.

By December 31 of each year, the licensee shall provide an annual report to the Resource 

Agencies detailing: the implementation of the FPOP, including any deviations from the FPOP 

and a process to prevent those deviations in the future; any proposed modifications to the FPOP, 

or in the case of emergencies or project outages, the steps taken by the licensee to minimize 

adverse effects on fisheries including any proposed modifications to those steps to further 

enhance their effectiveness in the future. The licensee shall offer to meet with the Resource 

Agencies by January 31 of each year unless a different date is mutually agreed upon by the 

licensee and the Resource Agencies. Any required modifications to the FPOP shall be submitted 

to the Resource Agencies within 45 days or receipt of a request for the modification unless a 

longer period is approved by the Department. The modifications to the FPOP shall be 

implemented consistent with the approval of the Department. In the event the licensee fails to 

submit the modifications as required by this paragraph, the Department, in consultation with the 

other Resource Agencies, may establish modifications and the licensee shall implement the 

modifications consistent with the approval of the Department.

The Licensee shall prepare the plan after consultation with the U.S. Fish and Wildlife Service, 

the Pennsylvania Fish and Boat Commission, the Pennsylvania Department of Environmental 

Protection, and the Pennsylvania Department of Conservation and Natural Resources.

The Licensee shall include with the plan documentation of consultation, copies of comments and 

recommendations on the completed plan after it has been prepared and provided to the agencies, 

and specific descriptions of how the agencies’ comments are accommodated by the plan. The 

Licensee shall allow a minimum of 30 days for the agencies and other interested organizations to 
46

comment and to make recommendations.

Inspection

The licensee shall provide personnel of the Department, and other Department-designated 

representatives, access to the project site and to pertinent project records for the purpose of 

inspecting the fish passage measures to determine compliance with the fish passage Prescription.

Consultation

The licensee shall develop in consultation with and submit for approval by the Department, all 

fish passage plans, schedules, and any supporting information to the fish passage measures

described herein.

American Shad Passage

Fish Passage Facilities and Structures

As indicated under “Alternatives Considered” section above the Department is not requiring the 

installation of any engineered facilities or structures (e.g., intake screens, instream flow diverters 

and baffles) to eliminate or substantially reduce project operational impacts to migratory fish 

attempting to pass the Muddy Run Project area at this time.

Fish Passage Measures

The Department concluded that that impacts migrating American shad are the direct result of the 

Muddy Run Project generation discharge and pumping withdrawal flows; and these impacts 

could be reduced or eliminated by regulating these operational activities during the annual 

periods of anadromous and catadromous fish migration.

The Department is requiring that the licensee develop Fish Passage Operating Procedures 

(FPOP) as described in detail above. The FPOP shall describe the licensee’s proposed baseline 

operations during fish passage season, including schedules for routine maintenance, procedures 

for routine operation (including seasonal and daily periods of operation, pump and turbine 

operations), sequencing of pump and turbine start-up and operation, procedures for monitoring 

and reporting flows, procedures for monitoring and reporting on the operation of the facility, 

procedures for start-up and shut-down, and procedures for use in case of emergencies and project 

outages significantly affecting the conditions of this prescription.

American Shad Passage Monitoring

The FERC determined that the process of mitigating adverse environmental impacts should 

include an assessment of the effectiveness of the mitigation that is implemented, and that in most 

cases, successful mitigation is dependent upon the development of such effectiveness monitoring 

plans (FERC 2004). The licensee shall implement an American Shad Passage Monitoring Plan

(ASPMP) approved by Department in order to monitor the effectiveness of upstream shad 
47

passage at the Muddy Run Project. Fish passage monitoring is (or will be) a condition of FERC 

license for the other four hydroelectric projects on the lower Susquehanna River. Each of the 

hydroelectric projects has engineered facilities or structures, and the associated project 

operations and measures as the primary form of upstream fish passage. Each of the existing

upstream passage facilities is equipped with a fish counting window where the number and 

species of fish passaging the project can be visually enumerated by an observer during the fish 

passage season. These counts are used to monitor the effectiveness of fish passage facilities at 

the FERC licensed hydroelectric project.

Since there are no engineered upstream fish passage facilities or structures at the Muddy Run 

Project provisions cannot be made for visual fish counts to monitor American shad passage at the 

Muddy Run Project. The only other method proven to be applicable to monitoring fish passage is 

tracking of a representative sample of migratory fish as was done during the licensee’s 2008 and 

2011 American shad radio telemetry study. FERC (2004) determined that a radio tagging study 

to estimate the proportion of fish that are passed upstream can be an appropriate method of 

assessing effectiveness, and that it is also an appropriate procedure for assessing the 

effectiveness of downstream passage.

Therefore the licensee monitoring plan shall include execution of the radio telemetry monitoring 

similar to that conducted in 2008 for adult American shad, and in 2011for juvenile American 

shad by the licensee’s consultant, unless some other technique is approved in advance by the 

Service. The monitoring measures contained in the ASPMP shall be conducted during the 2018 

fish passage season, and be repeated every ten years thereafter for the term of any new FERC 

license that may be issued for the project.

The licensee shall implement the ASPMP consistent with the approval of the Department. The 

licensee shall provide written documentation to the Resource Agencies that operational 

personnel have reviewed and understand the ASPMP signed by the operations manager of the 

Muddy Run Project.

Copies of the approved ASPMP and all modifications will be provided to the Resource 

Agencies.

By December 31 of each year in which studies are done, the licensee shall provide an annual 

report to the Resource Agencies detailing: the implementation of the ASPMP, including any 

deviations from the ASPMP and a process to prevent those deviations in the future; any proposed 

modifications to the ASPMP, or in the case of emergencies or project outages, the steps taken by 

the licensee to minimize adverse effects on fisheries including any proposed modifications to 

those steps to further enhance their effectiveness in the future. The licensee shall offer to meet 

with the Resource Agencies by January 31 of each year unless a different date is mutually agreed 

upon by the licensee and the Resource Agencies. Any required modifications to the ASPMP

shall be submitted to the Resource Agencies within 45 days or receipt of a request for the 

modification unless a longer period is approved by the Department. The modifications to the 

ASPMP shall be implemented consistent with the approval of the Department. 

The Licensee shall prepare the ASPMP after consultation with the U.S. Fish and Wildlife 
48

Service, the Pennsylvania Fish and Boat Commission, the Pennsylvania Department of 

Environmental Protection, and the Pennsylvania Department of Conservation and Natural

Resources.

The Licensee shall include with the ASPMP documentation of consultation, copies of comments 

and recommendations on the completed plan after it has been prepared and provided to the 

agencies, and specific descriptions of how the agencies’ comments are accommodated by the 

ASPMP. The Licensee shall allow a minimum of 30 days for the agencies and other interested 

organizations to comment and to make recommendations.

The licensee shall meet with the Resource Agencies to discuss the results of the above ASPMP.

The results of this study will be used to determine the need for and form of any additional fish 

passage measures or facilities. If the ASPMP results indicate that the Muddy Run Project is not 

meeting the passage goals prescribed herein, the licensee must propose measures calculated to 

meet the goals, and shall implement such measures upon approval by the Service, Pennsylvania 

DEP, and FERC, as needed. The licensee shall provide daily updates of monitoring results to the 

Resource Agencies. The licensee shall provide an annual report of the monitoring results to the 

Resource Agencies by December 31st of each year.

Downstream American Shad Passage Monitoring

The ASPMP described above will be used to monitor the downstream passage of adult outmigrating post-spawn American shad and assess the effectiveness of downstream passage 

measures at the Muddy Run Project. If the ASPMP results indicate that the Muddy Run Project 

is not meeting the passage goals prescribed herein, the licensee must propose measures 

calculated to meet the goals, and shall implement such measures upon approval by the Service, 

Pennsylvania DEP, and FERC, as needed.

American Eel Passage 

Eel Passage Measures

For the catadromous American eel the licensee proposes to work with other licensees on the 

Susquehanna River to implement both an upstream and downstream trap-and-transport program 

to provide American eel passage for upstream migrating juveniles and downstream migrating 

adults between the Conowingo and York Haven dams. No specific plans for the program were 

provided in the Muddy Run Project Draft License Application. However the PA DEP Proposed 

401 Water Quality Certification requires the implementation of trap and transport for juvenile 

American eel migrating upstream. We generally consider trap-and-transport to be an interim fish 

passage measure during the initial phase of a river restoration, and is appropriate for these initial 

stages, therefore this Prescription provides specific plans for a trap and transport program. As 

restoration efforts for American eel on the Susquehanna River progress, the capacity of PA DEP 

proposed trap-and-transport operation to move sufficient numbers of eel upstream will likely be 

exceeded and additional facilities and measures may be needed to accommodate adequate, safe, 

timely and effective passage through the Muddy Run Project area.
49

The licensee will need to develop a plan to assess placement, design and installation of facilities 

and measures needed to capture eel and provide safe, timely and effective eel passage past the 

Muddy Run Project. The plan should also include a description of studies to test the effectiveness 

of eel trap-and-transport as an interim means of passage at the Muddy Run Project. The licensee

should develop this plan in consultation and cooperation with the Department and state resource 

agencies and provide it to the Department and state resource agencies for review and approval 

before submitting it to the FERC for its review and approval. This American Eel Passage Plan 

(“Eel Plan”) is a condition of, and incorporated into this fish passage prescription.

To inform implementation of the Eel Plan, the licensee will establish an Eel Passage Advisory 

Group (EPAG) within 6 months of license issuance. EPAG will be chaired by the licensee and 

composed of a representative from each of the following (collectively, the “Resource 

Agencies”): the United States Fish and Wildlife Service (Service), Pennsylvania Department of 

Environmental Protection (PADEP), Pennsylvania Fish and Boat Commission (PFBC), the 

Maryland Department of Natural Resources (MD DNR), and the Susquehanna River Basin 

Commission (SRBC). Each designated representative shall be knowledgeable of American eel,

the Susquehanna River, ongoing fisheries and other related resource programs being 

implemented in the Lower Susquehanna River (e.g., American shad restoration).

Consistent with the implementation plan set forth below, the licensee will trap and hold 

immigrating juvenile American eels from a point downstream of the Muddy Run Project, and 

transport them to designated points in the Susquehanna River watershed consistent with the level 

of effort established and described in the plan. 

Trapping

Subject to required regulatory approvals, the licensee will design, install and operate eel trapping 

facilities according to the following schedule, unless an alternative schedule is approved by the 

Department in writing. In the event that the Resource Agencies or FERC determine that 

additional information, revisions, modifications, or amendments are necessary to the plans, 

specifications or construction activities, then within 60 days of receipt of written notice, the 

licensee shall submit to the Department, the Resource Agencies and FERC such information, 

revisions or amendments unless a longer period of time is approved by the requesting agency or 

FERC in writing. 

1. Submit complete design plans and specifications for a trapping facility at a location 

downstream of the Muddy Run Project to the Resource Agencies and FERC within 

one year of license issuance;

2. Hold preconstruction meeting with the Resource Agencies and Service within 150 

days of approval of the design plans and designs by FERC, the Resource Agencies

and Department;

3. Begin construction within 180 days of receipt of approval of the design plans and 

specifications by the Resource Agencies and the Department;

4. Begin operation on May 1 after construction is completed or immediately if 

construction is completed during the upstream passage period for American Eel.
50

Beginning immediately after license issuance and until the licensee’s trapping facilities are

completed, the licensee will work with the Service to trap eels using the Service trapping facility 

and will assist in the financial support of the Service trapping facility through a payment of 

$20,000 per year to an entity approved by the Department with the capability of providing 

financial support to the Service’s Maryland Fisheries Resource Office for the eel trapping 

program. This payment will be made by April 1 of each year. Immediately upon license issuance

the licensee will participate in this effort using the Service facilities, including the Service 

trapping facility, tanks and trucks. Beginning May 1 the first year after license issuance, the 

licensee will use its own holding and transport facilities and continue working with the Service 

to trap eels using the Service’s trapping facility. The licensee will begin operating the program 

independently, subject to the Service supervision and input, using its own trapping facility when 

construction of that facility is completed. 

Subject to required regulatory approvals, the licensee also will design, install and operate 

additional temporary eel trapping facilities downstream and upstream of the Muddy Run Project

or at alternative locations approved by the Department in writing according to the following 

schedule, unless an alternative schedule is approved by the Department in writing. In the event 

that the Resource Agencies, FERC, or the Department determine that additional information, 

revisions, modifications, or amendments are necessary to the plans, specifications or construction 

activities, then within 60 days of receipt of written notice, the licensee shall submit to the 

Department, the Resource Agencies and FERC such information, revisions or amendments 

unless a longer period of time is approved by the requesting agency or FERC in writing. 

1. Conduct field evaluation using visual observation, electrofishing and other methods 

approved by the Department and the Resource Agencies, in writing, to evaluate and 

rank trapping locations beginning on 1 May after construction is completed or 

immediately if construction is completed during the upstream passage period for 

American eel;

2. Submit complete design plans and specifications to the Resource Agencies by 

November 1withn the same year as field evaluations occurred;

3. Hold preconstruction meeting with Department and the Resource Agencies within 45 

days of approval of the design plans and designs by FERC, and the Resource 

Agencies;

4. Begin construction within 90 days of receipt of approval of the design plans and 

specifications by Department and the Resource Agencies;

5. Begin operation by May 1 the year after field evaluations occur.

If, after three years of operation, the Department in consultation with EPAG determines the 

temporary eel trapping facility is successful, the licensee will design, install, and operate a 

permanent eel trapping facility at this location in accordance with a schedule established by 

Department in consultation with the other Resource Agencies. 

If, after three years of operation, the Department in consultation with EPAG determines the

temporary eel trapping facilities for juvenile eels are unsuccessful, site-determination studies for 

an additional permanent trap will be performed beginning the following May. Congregations of 
51

juvenile eels will be documented visually via bi-weekly nighttime surveys during the migration 

period; the locations surveyed will focus on areas that will allow for the collection of eels before 

they are exposed to impacts associated with the Muddy Run Project (i.e., generation and/or 

pumping flows). Based on the results of the site-determination studies, the licensee will design, 

install, and operate temporary mobile traps to inform the potential location of one additional 

permanent eel trapping facility. Temporary exploratory traps will be installed and operated at up 

to five locations determined by the Resource Agencies and the Department for a period of one to 

two additional years, in order to assess the ability to collect sufficient numbers of juvenile eels 

for the eel passage program. Collection facilities for the temporary site determination study will 

be similar to those used in the 2011 and 2012 studies conducted by the licensee for the 

Conowingo Hydroelectric Project. 

Based on the results of the site-determination studies, the licensee, in consultation with EPAG, 

will determine if and where an additional permanent eel trap is justified in support of the Eel 

Passage Program. If a decision is made after the second site determination study to install an eel 

trap at the selected location, unless a different date is established by the Resource Agencies and 

the Department, that trap will be designed and constructed within one year of that determination, 

and operated beginning May 1 of the following year subject to required regulatory approvals. If a 

second year of study is needed, the dates would advance by a year.

The collection device(s) for the two permanent eel trapping facilities will consist of a ramp-style 

trap leading to a collection tank at the top of the ramp. The collection device(s) shall have a 

capacity to pass 50,000 eels over a 24 hour period accommodating a minimum size of 3 inches. 

One or more pumping systems will provide attraction flow at the entrance of the ramp, flow in 

the troughs to allow eels to climb the ramp, and water to the collection and holding tanks. The 

lower section of the ramp will be designed to have removable covers or grating to allow eels to 

enter at differing water surface elevations. The ramp will contain two side-by-side troughs to 

provide redundancy and allow for the potential use of different climbing media in each trough. 

For the ramp on the western shore, the entrance to the ramp will be designed to accommodate the 

normal range of tailwater elevation (El. 12 – 25 ft). The additional permanent collection facilities

will contain elements of the facility on the western shore with the design modified to 

accommodate local conditions. 

The trapping facilities will be operated continuously during the eel migration period from May 1 

to September 15. The licensee will monitor and record days fished, hours fished and the weather. 

Daily counts of eels will be recorded. The method of counting under various capture scenarios 

will be developed in consultation with the EPAG. Temperature data will be obtained from 

Monitoring Station 643 (located approximately 0.6 miles below Conowingo Dam near the 

western shoreline) to examine river temperature in relation to catch rates of juvenile eels. 

Biweekly subsamples of collected eels will be examined for various life history parameters (e.g., 

length, weight, and condition factor). A portion of the subsampled eels will be sacrificed and 

examined for the presence of Anguillicoloides crassus. Some of the sacrificed eels will have the 

otoliths removed and retained for age analysis. Anguillicoloides crassus infection rates 

(proportion of eels infected), the number of parasites per eel, along with associated age, length, 

and weight data will be reported. Additionally, the licensee will pay to have 60 elvers/year sent

to the Service or such other entity that the Department may approve in writing, for wild fish 
52

health screening. The screening shall occur once per year and can occur anytime during the eel 

upstream passage season. 

Holding

Subject to required regulatory approvals, the licensee also will design, install and operate the 

holding facility for the traps according to the following schedule, unless an alternative schedule 

is approved by the Department in writing. In the event that the Resource Agencies, FERC, or the 

Department determine that additional information, revisions, modifications, or amendments are 

necessary to the plans, specifications or construction activities, then within 60 days of receipt of 

written notice, the licensee shall submit to the Resource Agencies and FERC such information, 

revisions or amendments unless a longer period of time is approved by the requesting agency or 

FERC in writing. 

1. Submit complete design plans and specifications for holding facilities to the Resource 

Agencies within 1 year of license issuance;

2. Hold preconstruction meeting with Department and Service within 150 days of 

approval of the design plans and designs by FERC, Department and the Resource 

Agencies;

3. Begin construction within 180 days of receipt of approval of the design plans and 

specifications by Department and the Resource Agencies;

4. Begin operation by May 1, after construction is completed or immediately if 

construction is completed during the upstream passage period for American eel.

Periodically, consistent with standards established by the Department, and the Resource 

Agencies, eels will be transferred from the collection tank to the holding tank(s) where they will 

be held prior to being transported upstream. The holding tanks will have an automatically 

engaging back up pump and an alarm that sounds in a daily staffed location if the primary pump 

malfunctions. The holding tank will have continuous temperature, dissolved oxygen and 

gallon/minute water exchange monitoring devices with alarms that sound in a daily staffed 

location if levels of any parameter are outside of established limits. Upon observation, dead eels 

will be removed, enumerated, and reported. The holding tank shall be designed and operated to 

hold eels at densities not exceeding 10 elvers per liter unless modified by the Department in 

consultation with the other Resource Agencies. If necessary, aeration will be provided to the 

holding tanks

Transport

Subject to required regulatory approvals, the licensee will design, construct and operate 

vehicle(s) to transport eels from the trap facilities according to the following schedule, unless an 

alternative schedule is approved by the Department in writing. In the event that the FERC, the 

Resource Agencies, or the Department determine that additional information, revisions, 

modifications, or amendments are necessary to the plans, specifications or construction activities, 

then within 60 days of receipt of written notice, the licensee shall submit to the Resource 

Agencies and FERC such information, revisions or amendments unless a longer period of time is 

approved by the requesting agency or FERC in writing. 
53

1. Submit complete design plans and specifications to the Resource Agencies and FERC 

within one year of license issuance;

2. Begin construction within 180 days of receipt of approval of the design plans and 

specifications by the Department and the Resource Agencies;

3. Begin operation by May 1, after construction is completed or immediately if 

construction is completed during the upstream passage period for American eel.

Transport of juvenile eels will occur as necessary based on the capacity of holding tanks at the 

eel trapping facilities. All eels shall be moved within 1 week of capture. Eels from the holding 

tank(s) will be transferred to a transport vehicle equipped with an insulated transport container(s) 

that will be covered and aerated. The transport vehicle(s) will have an automatically engaging 

back up pump and an alarm that sounds in the cab of the vehicle(s). The transport vehicle taken 

will have continuous temperature and dissolved oxygen monitoring devices with alarms that 

sound in the vehicle(s) if levels of any parameter are outside of established limits. The transport 

vehicle(s) shall be designed and operated to hold eels at densities not exceeding 10 elvers per 

liter unless modified by the Department in consultation with the other Resource Agencies. If 

necessary, aeration will be provided to the holding tanks on the transport vehicle(s). These eels 

will be trucked to appropriate release locations on the same day of removal from holding. Upon 

observation, dead eels will be removed, enumerated, and reported. 

Release

The licensee will release eels at locations identified by the Department in amounts consistent 

with the release information provided to and approved by the Resource Agencies in writing. 

Where feasible, eels will be released at public access locations. Unless otherwise directed by the 

Resource Agencies in consultation with EPAG, eels will be released: (1) at least one hour after 

sunset to promote eel dispersal and minimize predation; and (2) into at least three feet of water at 

multiple locations within designated release areas in order to avoid concentrations of eels that 

could become potential targets for increased predation. If necessary due to time limitations 

established by the Resource Agencies in writing, the licensee shall release eels at alternative

locations to avoid mortality. The estimated number of eels released at each location will be 

documented in writing and on a GPS device capable of being mapped in a database as approved 

by the Resource Agencies. After release, any dead eels remaining in the transport vehicle or 

observed at the stocking locations will be removed, enumerated, and reported.

Any modification of, or revisions to, the release locations shall occur after consultation with 

EPAG and consistent with the approval of the Resource Agencies.

Quality Assurance/Quality Control

The licensee will develop a detailed quality assurance/quality control (“QA/QC) program 

according to the following schedule, unless an alternative schedule is approved by the 

Department in writing. In the event that the Resource Agencies, or the Department determine 

that additional information, revisions, or amendments are necessary to the QA/QC program then 

within 60 days of receipt of written notice, the licensee shall submit to the Resource Agencies 
54

and the Department such information, revisions or amendments unless a longer period of time is 

approved by the requesting agency in writing. 

1. Submit a draft QA/QC program to the Resource Agencies for approval by April 15, 

of the year in which a new license is issued;

2. Implement the QA/QC program approved by the Department when trapping and 

transport begin.

Important parameters associated with trapping, collecting, holding, transport, release, and 

stocking will be recorded to assure and control the quality of various program elements. The 

collection of these data will assure that the program will be conducted according to design 

parameters, will adhere to sound scientific principles, and will allow for any necessary 

adjustments. The results of these quality assurance and quality control measures will be included 

in annual reports to the Resource Agencies and EPAG. Changes to the QA/QC procedures shall 

be submitted as requested by the Department, or the Resource Agencies in writing.

At a minimum, the QA/QC program shall provide:

• Detailed description of the eel trapping and holding process to achieve a minimum 

95% survival rate.

• Detailed description of the eel transport process to achieve a minimum 95% survival 

rate.

• Collection facilities will be visually inspected daily to ensure proper operation. 

• Design parameters for flows and key critical components (e.g. attraction flow, spray 

bar, collection tank) that will be measured weekly and qualitatively assessed daily to 

ensure that traps are operating within design parameters.

• Water temperature and dissolved oxygen and water exchange in the collection, 

holding, and transport tanks will be monitored continuously to ensure that water 

quality remains suitable for juvenile eels.

• Information on the periodic checks on the accuracy of the estimates of volumetric 

counts.

• Information on the cleaning and disinfection of the collecting, holding, and 

transportation tanks. 

• Protocols for monitoring, removing, enumerating, and reporting eel mortality. 

Reporting, Monitoring, and Periodic Evaluation

Reporting and EPAG Meetings
55

During the eel passage season, the licensee shall provide a daily email to designated members of 

EPAG describing the status of trapping and trucking at each facility, the numbers of eels trapped 

and transported, any deviations from normal facility operations, and the timing and substance of 

the resolution of any deviations.

On or before December 10 annually, the licensee will submit a report to EPAG summarizing data 

from the trapping, collection, holding, transport, and stocking components of the Eel Plan for the 

calendar year. This report will provide program data to EPAG at the earliest practicable date, and 

provide EPAG with an opportunity to inform development of the Annual Report. On or before 

January 15 of the following year, the licensee will file an Annual Report with EPAG that 

analyzes annual data, including results from QA/QC. 

Upon request, the licensee will meet with EPAG on or before February 15 of each year in which 

the Annual Report is filed.

Periodic Evaluation

Every three years, unless a different period is established by the Department in writing beginning 

in in the year following issuance of a new license, the licensee will conduct stream segment 

evaluations through electrofishing or other method identified after consultation with EPAG. 

Representative stream segments will include tributaries and shorelines of the main-stem river. 

The licensee will propose locations and methods for this survey at least one year in advance to 

the Resource Agencies. The licensee shall implement the survey based on approval of the 

Department of the proposed locations and methods.

To implement the evaluations, eels will be captured by electrofishing, or other methods approved 

by the Department in consultation with the Resource Agencies. Sampling will be performed at 

block-netted transects along river shorelines and at block-netted segments of small tributaries 

using backpack electrofishing. The exact number, length, and location of transects sampled will 

be approved by the Department in consultation with EPAG. Associated water quality parameters 

such as temperature and dissolved oxygen, as well as habitat characteristics, including mussel 

numbers observed, will be collected at each sampling location. 

During sampling, the number of eels captured will be documented and data will be collected 

from a representative subsample of eels. A subsample of captured eels larger than 200 mm will 

be tagged with Passive Integrated Transponder (PIT) tags and released. Sampled eels will be 

scanned for PIT tags and data from recaptured eels will be recorded and included in the annual 

report. Data will include a variety of life history characteristics (e.g., length, weight, and 

condition factor) that can be assessed to determine how well stocked eels are utilizing the river 

and tributaries. A portion of the subsample will be sacrificed and examined for age (otolith 

analysis), gender, and level of Anguillicoloides crassus infection. Eels that are not sacrificed for 

further analysis will be measured, weighed, and released. 

Results of stream segment evaluations will be included in the Annual Report and will document 

dispersal of the stocked eels, estimate the approximate density of stocked eels, and evaluate the 
56

growth, condition, age, gender and level of infestation with Anguillicoloides crassus of stocked 

eels.

Downstream Eel Passage Monitoring

Licensee shall conduct of a downstream eel passage study to evaluate the timing, magnitude, 

duration, annual variation and environmental conditions associated with active migration of 

silver eels from tributaries stocked with elvers, through the lower Susquehanna River and past 

the Muddy Run Project to the Chesapeake Bay. This study will be conducted for at least two 

years and will begin three years after license issuance. The licensee shall submit a draft study 

plan for Department review and approval within one year of license issuance. The plan shall 

include details of how licensee will collect and radio tag adult silver eels from the upper 

Susquehanna Basin for this study. The plan will also detail how the licensee will deploy radio 

telemetry monitoring equipment in the vicinity of Muddy Run Project so as to adequately track 

movement of radio tagged eels through the project area. 

Concurrently with the downstream eel passage study or at a later date as approved by the 

Department, the licensee will also conduct a Site-Specific Route of Passage Study to evaluate the 

entrainment rate of silver eels migrating in the vicinity of the Project. If the results of the SiteSpecific Downstream Eel Passage Study indicate that the Project’s existing operating measures

do not meet the downstream passage criteria (survival of 85% of silver eels passing the Project), 

the Licensee will prepare and submit a plan and schedule for evaluating the feasibility and costs 

of potential physical and/or operational modifications to the Project to facilitate downstream eel 

passage.

Correspondence Regarding the Preliminary Prescription for

Fishways

Any written inquiries, comments or other correspondence related to this Preliminary Fish

Passage Prescription for the Muddy Run Project should be sent to:

Field Supervisor, Chesapeake Bay Field Office

U.S. Fish and Wildlife Service

177 Admiral Cochrane Drive

Annapolis, MD 21401
57

Appendix 1. Scientific Names

American eel (Anguilla rostrata)

American shad (Alosa sapidissima)

alewife (Alosa pseudoharengus)

blueback herring (Alosa aestivalis)

hickory shad (Alosa mediocris)

Alabama shad (Alosa alabamae)

gizzard shad (Dorosoma cepedianum)

shortnose sturgeon (Acipenser brevirostrum)

Atlantic sturgeon (Acipenser oxyrhynchus)

striped bass (Morone saxatilis)

walleye (Stizostedion vitreum)

smallmouth bass (Micropterus dolomieu)

channel catfish (Ictalurus punctatus)

Appendix 2. Administrative Record

The Administrative Record is being filed electronically under a separate cover due to its size.
APPENDIX F

Preliminary Fishway Prescription – Conowingo Hydroelectric Project
1

7. Statutory Authority

Section 18 of the Federal Power Act, 16 USCS §811, states in pertinent part:

The Commission shall require the construction, maintenance and operation by the 

Licensee at its own expense of such fishways as may be prescribed by the Secretary of 

Commerce or the Secretary of the Interior.

Section 1701(b) of the National Energy Policy Act of 1992, P.L. 102-486, Title XVII, §1701(b), 

106 Stat. 3008, states:

The items which may constitute a ‘fishway’ under section 18 [16 USCS §811] for 

the safe and timely upstream and downstream passage of fish shall be limited to 

physical structures, facilities, or devices necessary to maintain all life stages of 

such fish, and project operations and measures related to such structures, 

facilities or devices necessary to ensure the effectiveness of such structures, 

facilities, or devices for such fish.

8. Alternatives Considered

The Service’s Fish Passage Engineers (R5 FPE) examined seven alternative designs for the 

Conowingo Hydroelectric Project (Project) and created a matrix for selection and comparison 

purposes (USFWS 2013g). The seven alternative design concepts described in section 8.2 are 

based on existing fish passage facilities found acceptable to pass significant numbers of American 

shad in large rivers (>1000 square mile drainage areas). The selection of the alternative concepts 

below was made on the basis of improving fish passage efficiency and capacity only. Service

engineering efficiency reviews showed delay to be a critical issue. This concern is validated by the

2010 and 2012 radio-telemetry study which revealed that passage efficiency was 10% and 0%

within the 36 hour timeframe for the 2010 and 2012 studies, respectively (USFWS 2013a). 

Regarding fishway capacity in general, fishway passage capacity is a measure of the quantity of

fish (typically expressed in adult shad-equivalent) that the facility is designed to successfully

convey, upstream or downstream, in a given period. It is distinct and separate from fishway

hydraulic capacity.

Early field and design fish passage engineering reviews (USFWS 2012a and 2012b) determined 

that a critical issue with the existing EFL is insufficient lift capacity (even with expanded or larger

hoppers) to meet the restoration goals for the American shad (approximately 5 million American 

shad past Conowingo to yield 2 million upstream of York Haven Dam given less than 100%

passage at all other hydroelectric facilities). In order to address this issue, R5 FPE has identified 

seven design alternatives that would increase passage capacity, while also enhancing other aspects 

of fish passage. Sequencing of construction is considered a tool to track and meet the performance

of the anticipated population growth curve and was not used in the alternatives analysis since the

incremental improvements are of little consequence if the final product does not meet the

restoration plan goals.
2

8.1 Common To All Alternatives

There are certain elements common to all alternatives considered, primarily the design 

populations, operational periods, effectiveness testing, and eel passage, addressed below.

8.1.2 Design Criteria

8.1.2.1 American Shad Weight

The Service standard for American shad weight in fish passage capacity designs is four pounds 

and has been used for over 30 years on Atlantic Coast. Fish passage design is not developed for 

the “average” size fish, but rather must be more conservative in approach to accommodate for 

larger individuals within the population. In addition, American shad stocks have been heavily

impacted in recent years by a variety of sources which have decreased the age and size structure 

compared to a healthy population (ASMFC 2007, Volume I). When designing fish passage 

projects, we need to anticipate the population as a restored and healthy population and not the 

current depleted state.

Regional data from American shad in both the Susquehanna River Flats and the Delaware River 

support the 4-pound design criteria when accommodating larger fish that occur in the system. 

Using the Delaware River shad data as a comparison to the Susquehanna River shad is appropriate

because the Delaware River is geographically close, so it is fair to assume that the population 

demographics would be similar in size of individuals and frequency of repeat spawners. The

Delaware River is also an appropriate comparison because the shad population is not impacted by

mainstem dams, as with the Susquehanna River population. Because the situation warrants 

designing fish passage for the larger than average fish, we used the 95th percentile of American 

shad weights in regional datasets to support our use of the 4-pound standard in considering design 

and capacity of Susquehanna River fish passage facilities (Table 1). Such large fish are

disproportionately valuable to the population, being exclusively female and with a high proportion 

of repeat spawners that have high fecundity (ASMFC 2007, Volume I).

Table 1. American Shad Weight for Fish Passage Capacity Design

Location Average (lbs.) 95th Percentile (lbs.)

Susquehanna Flats1 2.34 3.17

Upper Delaware River

2 2.55 4.03

Lower Delaware River3 3.71 5.97

1

Data from Maryland Department of Natural Resources, Susquehanna Flats surveys from 2009-2013 2

Data from the USFWS Delaware River Coordinaor, unpublished data on the Upper Delaware River American shad collections from

2009-2013 3

Data from the USFWS Delaware River Coordinator, Delaware River Lewis Haul Seine Fishery from 1997-2006
3

8.1.3 Design Populations

8.1.3.1 American Shad

Under all action alternatives, fish passage needs to be adequate to maintain self-sustaining annual 

populations of 2 million American shad migrating up to and reproducing in the free-flowing 

Susquehanna River upstream of York Haven Dam and in suitable tributaries. In order to attain 2 

million American shad upstream of York Haven Dam, at least 5 million shad will need to pass 

Conowingo Dam given that fish passage at other hydroelectric projects is less than 100%.

8.1.3.2 River Herring (Alewife and Blueback Herring)

Under all action alternatives, fish passage needs to be adequate to maintain self-sustaining annual 

populations of 5 million river herring, migrating up to and reproducing in the free-flowing 

Susquehanna River above York Haven Dam and in suitable tributaries. In order to attain 5 million 

river herring upstream of York Haven Dam, at least 12 million herring will need to pass 

Conowingo Dam given that fish passage at other hydroelectric projects is less than 100%, and 

assuming that dams have the same passage efficiency for herring as they do for shad.

8.1.3.3 American Eel

Under all action alternatives, fish passage needs to be adequate to pass all available upstream 

migrating eels that arrive to Project into the mainstem of the Susquehanna River above the York 

Haven Dam. Downstream migration of adult eels must be safe, timely and effective, achieving an 

85% survival rate past the Project.

8.1.4 Scheduling

Timely construction, operation, and maintenance of fishways is necessary to ensure their 

effectiveness and to achieve restoration goals. Therefore, all action alternatives would include the

express requirement that the Licensee (1) notify, and (2) obtain approval from the Service for any

extension to comply with conditions the Department may prescribe. Under all action alternatives, 

fishways would have to be maintained to maximize fish passage effectiveness throughout the

upstream and downstream migration periods for American shad, alewife, blueback herring, 

American eel, and associated riverine fish.

Fishway for upstream passage of anadromous fish would be operated daily during the American 

shad and river herring upstream migration season. Daily operation of the WFL and the EFL would 

be from dawn to dusk until water temperature surpasses 21oC for three consecutive days. Fish lift 

operations will start March 1 or when river surface temperatures reaches 48oF (9oC), whichever

occurs first, in order to accommodate the earliest migration of anadromous fish. Fish lift attraction 

flow will operate continuously during the fish passage season to provide upstream migration cues 

at the fishway entrance and minimize delays at the start of each passage day. Fish lifts would have

to be repaired and maintained as necessary in advance so as to begin operations when required.

Fish passage facilities for upstream passage of catadromous fish would be operated 24 hours per 

day during periods as provided in Table 2, below.
4

Table 2: Upstream and downstream migration periods for species covered in this Preliminary 

Prescription for Fishways. *

Species Upstream Migration Period Downstream Migration

Period

American shad April 1 through June 15 July 1 through November 15 

(juv.)

April 15 through July 1 (adult)

Alewife & blueback herring March 1** through June 15 June 15 through October 14 

(juv.)

April 15 through July 1 (adult)

American eel May 1 through September 15

***

September 15–February 15, 

whenever river temperature is 

above 37 degrees F ****

* Any of these migration periods may be changed during the term of the license by the 

Department, based on new information, and in consultation with the other fishery agencies and 

the Licensee.

** This operational period is based on alewife migration timing from other tributaries to the

Chesapeake Bay (Sutherland 2000, Eyler et al. 2002, Slacum et al. 2003).

***This initial operational period is based on preliminary data on American eel migration at

Conowingo Dam (SRAFRC 2013a).

**** The Department is calling for the Licensee to study the magnitude and timing of 

downstream eel migration through the project so that the effectiveness of a reduced period can be 

evaluated. This initial operational period is based on preliminary data on American eel migration 

timing from other tributaries to the Chesapeake Bay (Welsh et al. 2009).

8.1.5 Fishway Operating Procedures

Under all action alternatives, within 12 months of license issuance, the Licensee would have to 

develop a Fishway Operation and Maintenance Plan (FOMP) and submit it to the Resource 

Agencies for review and approval. The FOMP would address regular maintenance activities as 

well as emergency procedures for fish passage. The Licensee would meet on an annual basis with 

the Service and the Susquehanna River Anadromous Fish Restoration Cooperative (SRAFRC) to 

discuss the FOMP. This meeting would occur no later than January 15 each year. This meeting is 

a continuation of the traditional SRAFRC Fish Passage Technical Committee (FPTC) meetings 

with the dam owners on the river to review the FOMP, fish passage results from the previous year

and expectations for fish lift/fishway operations for the upcoming season. Participants at these

meetings include: staff from the states of Maryland and Pennsylvania, Susquehanna River Basin 

Commission, National Marine Fisheries Service and the Service.

The FOMP will include, for each fishway, schedules for routine maintenance, procedures for 

routine operations (including: seasonal and daily periods of operation, dam and powerhouse 
5

operational measures) detailing with how the plant shall be operated during the fish passage 

season, including: sequence of turbine start-up and operation; debris management; plant 

operations to provide near- and far-field attraction flows required for optimum fish passage; 

standard operating procedures for monitoring and reporting on operations that affect fish passage; 

and standard operating procedures in case of emergencies and project outages to first, avoid, and 

second, minimize, negatively affecting fishway operations and the effectiveness of upstream and 

downstream passage of target species life stages.

The Licensee would have to provide written documentation to the Resource Agencies that all 

fishway operational personnel have reviewed and understand the FOMP signed by the operations 

manager of the Project.

Copies of the approved FOMP and all modifications would have to be provided to the Resource 

Agencies.

By December 15 of each year following issuance of a new license, the Licensee would provide an 

annual report to the Federal and state resource agencies memorializing implementation of the 

FOMP. If there were deviations from the FOMP, they and measures to avoid those deviations in 

the future would be described. The report would contain any proposed modifications to the 

FOMP. If there are emergencies or project outages, the report would include steps taken to avoid 

adverse effects on fishway passage, and how the effectiveness of those steps could be enhanced. 

The Licensee would meet with the state and Federal resource agencies by January 31 of each year

unless a different date is mutually agreed upon by the Licensee and the state and Federal resource

agencies. Modifications to the FOMP requested by the Service would be submitted to the state and 

Federal Resource Agencies for their review within 30 days of receipt of it being requested unless a

longer period is approved by the Service. The modifications to the FOMP would be implemented 

consistent with the approval of the Service.

For fish passage measures that do not begin operation upon license issuance, 60 days prior to 

operation of the enhancements and/or facilities, Conowingo Project would have to submit FOMP 

provisions for any such new fish passage enhancements, facilities and measures to the Resource 

Agencies for review and approval and shall implement the FOMP as approved by the Service.

8.1.6 Eel Passage

Under all action alternatives, a trap and truck (T&T) facility for American eels would be 

constructed on the west side of the river no later than one year after the completion any WFL 

construction, or within a year of license issuance under any action alternatives not involving 

reconstruction of the WFL. Volitional eel passage would be implemented by 2030. The specific 

location for collecting eels to T&T, the location of a permanent volitional eel passage, and other 

design criteria would be approved by the Service following consultation with the Licensee and 

Maryland Department of Natural Resources. Eel T&T activities would continue through 2029, 

switching to volitional passage in 2030. The eel passage facility would be operated continuously 

(24 hrs/day), during the American eel upstream migration season. Eels would be stocked at 

locations in the Susquehanna River Basin with the prior approval of the Service and respective 

state resource agency and consistent with the SRAFRC American Eel Restoration Plan.
6

This requirement would be included because the Susquehanna River Anadromous Fish 

Restoration Cooperative American Eel Restoration Plan (SRAFRC 2013b) calls for providing an 

upstream T&T program from Conowingo to various locations in the Susquehanna River Basin 

above Conowingo Dam for juvenile (elver) American eel. The goal of the plan is to ensure that 

every American eel that approaches Conowingo Dam is passed upstream into the Susquehanna 

River Basin in order to restore American eels to the watershed, to provide a net increase of outmigrating American eel, and restore the ecosystem functions provided by healthy American eel 

populations, including their role as predator and prey as well as acting as hosts for the glochidia of

Elliptio complanata.

All action alternatives would further require the Licensee to evaluate potential trapping locations 

for American eel on the east side of Conowingo Dam or Octoraro Creek starting in May the first 

calendar year after license issuance or immediately if license issuance occurs during the American

eel upstream migration period. By May 1 of the second calendar year after license issuance, the

Licensee would be required to install and operate temporary T&T facilities for American eel at the

eastern location. A permanent T&T facility for American eels on an eastern location would be

required within 5 years of license issuance, with the location of a permanent eelway and other

design criteria to be approved by the Service following consultation with the Licensee and the

respective state resource agency. T&T activities at the eastern location would continue through 

2029, with stocking locations throughout the Susquehanna River Basin as indicated above. In 

2030, T&T operations would continue with stocking exclusively into Conowingo Pool. The eel

passage facility would be operated continuously (24 hrs/day), during the American eel upstream 

migration season.

This requirement would be included because American eels approach the dam along both sides of

the river and are not likely to cross the dam face (no crossing of eels was documented by Park and 

Minkkinen 2010 or Exelon 2011b. This second collection location is necessary to collect elvers 

that may be traveling up the east side of the Susquehanna River.

8.1.7 Effectiveness Monitoring

All action alternatives would require the Licensee to develop a Fishway Effectiveness Monitoring

Plan (FEMP) in consultation with the USFWS and submit it to the FERC for approval within 6 

months of license issuance. The FEMP would consist of:

8.1.7.1 Plan for Post-Construction Efficiency Testing of Project Fishways

Post-construction efficiency testing of the Project facilities for adult upstream-migrating 

American shad and juvenile American eel would be conducted after any significant changes in 

project structures or operations are made during the term of the license. This would include both 

radio-telemetry studies of passage effectiveness and a post-licensing computational fluid 

dynamics (CFD) model study of the tailrace to investigate permutations in the operation of the 

eleven turbines to identify which combinations improve fish passage conditions in the tailwater at 

the rebuilt fish lifts. The existing tailrace condition has been documented to cause delay of 

migratory fish attempting to locate the entrances to the fish trap and fish lift (Exelon 2011a and

2012c). American shad, in particular, are easily disoriented by the turbine boils and tailwater 

conditions. Similar delay conditions have been addressed at Safe Harbor, through adjustments in 

turbine operations and continuous monitoring of fish passage conditions. A CFD model study 
7

will also provide important information to be used during the license term to refine fish passage 

measures.

8.1.7.2 Plan for Effectiveness Testing for Juvenile American Shad and Adult American Eel

Additional turbine survival studies should be conducted to ensure that any changes in structure or 

operation as a result of relicensing continue to meet the Plan goal for juvenile American shad 

survival of 95%. Juvenile shad studies will incorporate route of passage and passage efficiency 

through the Project impoundment as well as through the Project itself.

American eel studies will determine the timing of downstream migration, route of passage at the 

Project, and turbine specific injury and mortality rates for the Project. Survival past the Project 

must meet the Plan goals of 85% survival for adult American eels. We would also require that 

turbine mortality studies be done to determine both immediate and latent mortality and injury to 

migrating adult eels that has not yet been evaluated at this project. American eels collected from 

the Susquehanna River should be used in all future studies to ensure that the timing of migration 

is not altered by transferring eels from another basin and that eels used in studies are of 

representative size of what is migrating out of the river.

In the event Exelon is unable to achieve the downstream passage and survival goals for juvenile 

American shad and adult American eels, the next step will be to evaluate changes in operation 

and fish guidance systems to provide safe, timely and effective downstream fish passage. Fish 

guidance systems have been reviewed and the Service developed a presentation on this topic 

(USFWS 2013d).

By December 15 of each year, the Licensee would have to provide an annual report detailing; the 

implementation of the FEMP, including any deviations from the FEMP. The Licensee would

have to meet with the Resource Agencies by January 15 of each year unless a different date is 

mutually agreed upon by Conowingo Project and the Resource Agencies. Any required 

modifications to the FEMP would have to be submitted to the Resource Agencies within 30 days 

of receipt of a request for the modification unless a longer period is approved by the Service. The

modifications to the FEMP would have to be implemented consistent with the approval of the

Service.

8.2 Engineering Alternatives

8.2.1 Engineering Alternative A: East Fish Lift (EFL), 1/2 Gallery & Kaplan Mods

Engineering Alternative A is defined by the following upgrades to the EFL in order to increase 

the number of fish capable of being passed (hereafter termed “passage capacity”). Upgrades 

include reductions in the lift cycle time, construction of a second and larger hoppers designed to 

operate simultaneously with the existing one, additional entrance locations provided by the half 

gallery, and modifications to the Kaplan’s discharge flow (allowing for a more attractive 

entrance signal).
8

Service calculations demonstrate that two 6,500 gallon hoppers do not offer sufficient capacity to 

effectively transfer 5 million American shad (the number of fish required within a single season

to achieve sustainable restoration in the Susquehanna River) upstream of the Conowingo Dam

(USFWS 2013e). The Service also predicts that the aforementioned alternative will not achieve

80% passage efficiency (of the available American shad located in the tailrace) within a 

timeframe of 36 hours or less mainly due to the expected recurrence of observed delays from 

previous studies.

Existing data also suggest that fish might be approaching the Project closer to the west bank of 

the tailrace, away from the Kaplan’s discharge and the proposed half gallery (MDNR 2013, 

Exelon 2011a, 2011c and 2012c). Modifications to the Kaplan’s discharge could only be 

considered as an experimental approach, because the modifications have not been tested at other 

projects in the Northeast. This alternative lacks the significant improvements the Service 

considers to be needed at the West Fish Trap & Transport Facility in order to provide effective 

trapping of 50,000 American shad annually. Restoration goals rely heavily on a successful trap & 

transport program at the Conowingo project (Pugh 2013) and therefore improvements are 

warranted.

8.2.2 Engineering Alternative B: EFL, Full Gallery & No Kaplan Mods

Engineering Alternative B proposes upgrades to the EFL that would increase passage capacity.

This would be accomplished via reductions in the lift cycle time as well as a second hopper 

designed to operate simultaneously with the existing one. This alternative recognizes discharge 

from the Kaplan turbines as a longitudinal barrier and resolves it by providing a full collection 

gallery to minimize delay. Additional entrance locations provided by the full gallery are 

considered in this alternative for the purpose of enhancing attractive entrance signal and 

improving passage efficiency. The additional entrance locations minimize the turbine turbulence 

issue to attract and pass more fish.

This alternative shares the deficiencies of Engineering Alternative A, and also lacks the 

significant improvements at the West Fish Trap & Transport Facility and the possible increase in 

effectiveness or efficiency from the lengthened gallery is still limited by the insufficient lift 

capacity as the main cause for rejection.

8.2.3 Engineering Alternative C: East Fish Lock & 1/2 Gallery

Engineering Alternative C would address the issue of insufficient capacity under the current 

super structure by construction of a fish lock to provide additional capacity and avoid the need 

for sorting gizzard shad at the Project. Fish locks work similar to fish lifts in attracting fish 

through a collection gallery and crowding them at a holding pool before moving them over the 

dam. The main difference between these two technologies is the mechanism the lock uses to 

move the fish up into the exit channel. Instead of using a hopper (or bucket), a lock produces a 

column of water that starts at the tailwater elevation and rises to the head pond elevation. This 

method of elevating the fish upstream of the dam represents less stress on the migrating fish by 

handling them in a more benign way. The half collection gallery would serve as a channel into 

the holding pool of the lock.
9

The capacity of a lock is driven by the capacity of the holding pool, which means that renovations 

for the existing entrance channel would still be warranted. The Service also predicts that the

aforementioned alternative will not achieve 80% passage efficiency (of the available American 

shadlocated in the tailrace) within a timeframe of 36 hours or less for the same reasons cited in 

Engineering Alternative A.

8.2.4 Engineering Alternative D: EFL, 1/2 Gallery, Kaplan Mods & Sorting

Engineering Alternative D proposes upgrades to the EFL to increase fish passage capacity. This 

would be accomplished via reductions in the lift cycle time as well as a second hopper designed to 

operate simultaneously with the existing one. Additional entrance locations provided by the half

gallery and modifications to the Kaplan’s discharge flow (allowing for a more attractive entrance

signal) are considered in this alternative for the purpose of enhancing passage efficiency. The fish 

sorting would try to differentiate between the American shad and the gizzard shad. Preventing 

gizzard shad from entering the EFL hoppers would reduce the clogging in the EFL, increase the

overall capacity for American shad, and improve passage efficiency.

The one difference with this alternative relative to A, B, and C is the element of sorting which 

the Service does not consider to be adequate to increase the capacity enough to meet the 

restoration goals. Both the modifications to the Kaplan’s discharge and the fish-sorting could 

only be considered as experimental approaches. The difficulty with effectively discerning a 

gizzard shad from an American shad lies in the strong similarities between these. The two 

species share almost identical migration periods, the average size of their migrants are not

noticeably apart, and their swimming speed capabilities are comparable. Sorting out gizzard 

shad could also result in sorting out target species, like river herring.

8.2.5 Engineering Alternative E: Kaplan Draft Tubes Extension, EFL, 1/2 Gallery & 

Complete WFL

Engineering Alternative E also proposes upgrades to the EFL to increase fish passage capacity. This 

would be accomplished via reductions in the lift cycle time as well as a second hopper designed to 

operate simultaneously with the existing one. Additional entrance locations provided by the half

gallery are recommended for the purpose of enhancing passage efficiency. The Kaplan draft tubes 

extension would move the turbulent boil downstream and away from the EFL entrances. The

Service expects the extensions to enhance passage efficiency. The complete WFL would provide

volitional access to shad sounding in the western side of the power house. The Service is confident 

that this alternative would improve fish passage efficiency to 80% within a timeframe of 36 hours 

or less. The newly renovated WFL would also include a trap and transport facility. Sustainable

restoration goals rely heavily on a successful trap & transport program at the Conowingo project 

and therefore improvements are warranted (MDNR 2013).

The main cause for rejection is the expected high cost and experimental nature of the extension of

the Kaplan draft tubes. 
10

8.2.6 Engineering Alternative F: EFL Entrances Relocation, 1/2 Gallery & Complete

WFL

Engineering Alternative F upgrades to the EFL would also increase fish passage capacity. This 

would be accomplished via reductions in the lift cycle time as well as a second hopper designed to 

operate simultaneously with the existing one. Existing entrances A and B will be relocated in such a

way to avoid the boil in front of the Kaplan units (USFWS 2013d). Access to entrance A will be

available along the catwalk, through the area behind the piers, similar to the configuration at the

Safe Harbor project. The relocation of entrance A will make it functional again (it currently gets 

drowned by the discharge of the Kaplan’s). Additional entrance locations provided by the half

gallery are considered in this alternative for the purpose of enhancing passage efficiency. A new 

and complete WFL would provide volitional access to migratory shad sounding in the western side

of the power house. The newly renovated WFL would also include a trap and transport facility. 

Sustainable restoration goals rely heavily on a successful trap & transport program at the

Conowingo project and therefore improvements are warranted.

8.2.7 Engineering Alternative G: Phased WFL and EFL improvements

8.2.7.1 Phase I

Item #1 - West Fish Lift - Construct a new fish lift in the west corner of the powerhouse tailrace 

by 2017. The West Fish Lift (WFL) would operate as a tailwater to headpond fish-lift, and as a 

trap-and-truck (T&T) fish passage facility. The new WFL would include two 6,500 gallons 

hoppers to move fish simultaneously. The modern T&T facility will be capable of safely and 

effectively accommodating at least 50,000 American Shad per year and available river herring. 

Captured fish would be trucked and released into the Susquehanna River at Exelon’s Three Mile 

Island Nuclear Power Plant (TMI), or another river access point upstream of TMI. Trap-andtruck activities would continue through the life of the license or until the Service determines the 

activity has met management needs. Initial fish passage efficiency testing American shad and 

river herring at 80% efficiency within 36 hours and/or at an average seasonal efficiency of 85% 

will begin following construction of the WFL.

Construction of the WFL is considered essential to achieve the timely restoration of fish passage 

targets presented in the Susquehanna River’s Migratory Fish Management and Restoration Plan 

(Plan) for the Susquehanna River Basin in 2010 (SRAFRC 2010). Significant fish passage 

improvements are considered necessary at the Conowingo Hydroelectric Project (Project) to 

achieve restoration passage goal of 80% effectiveness for upstream passage in 36 hours or less 

(85% total) of American shad and river herring. In the 2010 radio-telemetry study for American 

shad upstream passage, only 10% of the available American shad passed within 36 hours or less 

from the time at which each fish crossed the downstream boundary of the Project’s tailrace 

(USFWS 2013a). The conceptual design calculation gives the sizing calculation that explains 

why the WFL should be built with two 6,500 gallons hoppers operating simultaneously (USFWS

2013c and 2013e).

Simulations of the American shad population via modeling (Exelon 2012b), showed notable fish 

population benefits from a T&T program, especially during the first 10 to 15 years of restoration 

(Pugh 2013). Without a T&T facility transporting American shad upstream the York Haven 

Power Company dam, the shad model indicates restoration will take longer. If 50,000 American 
11

shad are captured and transported upstream of the York Haven project in a single season, the

more likely it will be to achieve sustainable restoration during the license term. Having the WFL 

serving as both a T&T facility and a full-lift will help avoid the gizzard shad recycling issue that 

is currently an obstruction to passage and keeping American shad from ever entering and using 

the facility.

Item #2 - Auxiliary Water System (AWS) - The WFL would provide at least 3% of hydraulic 

capacity of the Project (2,600 cfs) for attraction flow. WFL attraction flow would be provided 

continuously (24/7) during the anadromous fish migration season. Continuous daily flow can be 

reduced to specific hours based on the results of effectiveness testing.

Construction of an AWS is necessary to meet the attraction water criteria and build in the 

increased efficiency needed to complete the restoration and meet the Project’s fish passage goals. 

The prescribed attraction flow is in conformance with Service design standards, which require a 

minimum of 3% of the powerhouse turbine capacity emanating from the entrances of the fishway 

and hydraulically connected crowder/hopper system (USFWS 2013b).

Item #3 - Provide a zone of passage to the lift facilities – The Licensee would modify the 5,000-

foot section of the east and west banks immediately below the powerhouse to provide a 

contiguous zone of passage to the lift facilities. The zone of passage will meet the biological 

needs and performance capabilities of American shad and river herring.

Figure 3. Conowingo Dam Construction in 1927 (Footnote 2).

The zone of passage is an integral element in the overall effectiveness of the fish lifts and is 
12

considered a part of the fishway(s). This definition is in keeping with 16 U.S.C. § 811.

1 This 

area immediately below the dam appears to have been modified during channel modification in 

19272(Figure 3). An effective zone of passage must maintain flow velocities high enough to 

trigger a rheotactic response in upstream migrating fish yet lower that the sustained swimming 

speeds of the weakest target species (i.e., river herring). Based on published values and 

methodologies for estimating sustained speed and associated fatigue times (USFWS 1986, Bell, 

1991, Bain, 1999, Maine DOT 2004), the zone of passage must generally maintain 

instantaneous velocities between 1 and 3 feet per second over the range of fish passage design 

flows separated only by brief regions of higher velocity that river herring may traverse in 

seconds at burst speeds up to 6 feet per second (e.g., flow over weir crests). Hydraulic modeling

of the Project indicates that depth averaged velocities in the tailrace exceed the capabilities of

these fish over a significant range of design flows. Initial investigations by the Service indicate

this 5,000-foot zone of passage on the eastern bank can be created through construction of

multiple placed-rock stream barbs or bendway weirs (USACOE 2007) that will reduce the

impassable velocities documented by hydraulic modeling. Design of this zone of passage or

equally effective alternatives must be developed in consultation with, and approved by, the U.S. 

Fish and Wildlife Service and the Maryland Department of Natural Resources.

Item #4 - Control turbine ramping rates during the migration period - A maximum downramping rate of 20,000 cfs per hour will be maintained during the upstream fish passage season.

Rapid down-ramping of turbines has shown to create fish stranding (FLA, Exhibit E, -156). 

Stranded fish are delayed or killed, and will not be able to pass the project in a safe and timely 

manner. In order to reduce fish stranding below the east side of the dam spillway the maximum 

rate of 20,000 cfs per hour is needed. This will also provide a longer window of desired far-field 

and short-field fish attraction and movement toward the powerhouse tailrace and into the areas

around the fishway entrances.

Item #5 - Construct and evaluate channel modifications – The Licensee would perform in-river 

modifications of the channel below the dam to hydraulically link disconnected pools so that an 

effective egress route is provided for stranded fish.

Fish stranding in the bypass channel is a concern. As stated by Exelon, “In addition, under 

Exelon’s proposed alternative the current peaking operations of the Project would continue to 

have impacts relative to fish stranding in the Conowingo Dam spillway (Exelon 2012a, FLA E156)”. Low flow channels and isolated pools need to be linked and a clear egress route provided 

to the Susquehanna River downstream in order to address the current fish stranding.

8.2.7.2 Phase II

Phase II modifications to the EFL would start in the year the WFL begins operation. 

Item #1 - Construct stilling basin modifications - Increase the size and height of the sill at the 

stilling basin located behind the EFL hoppers. Rebuild the EFL stilling basin sill high enough so 

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that the energy from a 900 cfs flow can be appropriately dissipated, by Service standards, before 

being diverted and utilized as attraction flow for the EFL.

The original design for the EFL requires 900 cfs of attraction flow to achieve preferred hydraulic 

conditions (e.g., water velocities) inside the fish lift, and to meet Service fishway design criteria. 

Currently the EFL operates with only 300 cfs because of its inability to dissipate enough energy 

from the flow before diverting it into the fish lift.

Item #2 - Relocate existing entrance A to the EFL – Extend the entrance channel at entrance A 

with two 90-degree bends, to discharge into the area behind the catwalk piers and upstream from 

the Kaplan turbine discharge/boil. The attraction flow should be effective all along the catwalk, 

and through the space between the piers (USFWS 2013d).

Given the bathymetry behind the piers, and the relatively quiescent flow pattern there, the 

attraction flow discharging from the relocated entrance gate A would provide an expected 

entrance jet and create a distinct flow path that should guide migratory fish into the EFL facility. 

This concept is similar to what exists along the powerhouse at Safe Harbor (the most successful 

fish passage facility in the Susquehanna River). The new location would also keep entrance A 

from being drowned by the turbulent boil that is caused by the discharge from the Kaplans’ draft 

tubes. Currently entrance A is inoperable when adjacent Kaplan units are generating.

Item #3 - Construct an Entrance D and entrance gallery for the EFL. Construct a gallery the full 

length of the Kaplan turbine section of the powerhouse to provide access to the new and second 

hopper from the Francis turbine section of the powerhouse. The new channel will be located 

against and along the powerhouse wall (USFWS 2013f). 

The existing fish lift entrances are considered ineffective at guiding and capturing migratory fish 

that are being attracted and held by the false attraction flow in the center of the tailrace produced 

by the discharge from the turbines. The Service expects modified operations of the turbine near 

the gallery, in combination with the relocated entrance A, would increase the total number of 

migratory fish using the EFL, reduce the average time for complete passage of all available fish, 

and add to the overall fish passage season capacity of the Project.

Item #4 - Reconstruct Entrance B – The existing entrance B would be modified such that the 

centerline of the discharge plume will be at a 45 degree angle to the river flow.

Successful fishways must create hydraulic signals strong enough to attract fish to one or multiple 

entrances in the presence of the competing powerhouse flows (i.e., false attraction). The angled 

discharge is considered to have a better chance of attracting fish into the fish lift by providing an 

attraction jet not only downstream from the fishway, but also into zones within the Kaplan 

discharge. The Service expects this modification to reduce the average time for complete passage 

of all available fish.

8.2.7.3 Phase III

In the event that after Phase II, American shad and river herring are not passing at 80% efficiency 

within 36 hours and/or at a total seasonal efficiency of 85% (defined by the ratio of passage count 

to population estimate or determined through telemetry tagging studies) one or more of the 

following adaptive measures would be required by the Service after consultation with the
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Licensee:

a. Daily adjustments to the instantaneous minimum flows that create low-flow periods for 

fish passage while maintaining overall daily average flow

b. Modified turbine operations that enhance fish passage

c. Construction of an EFL Auxiliary Water Supply (AWS) - Construct a new AWS stilling 

basin and system so that up to 4,325 cfs can be dissipated and incorporated into the 

attraction flow emanating from the multiple entrances

d. Upgrade existing fish lift equipment at the EFL so that the cycle time of every hopper is 

reduced to 15 minutes and the overall project capacity increased

e. Any combination of the measures listed above or other options agreed to by the Service 

and the Licensee

Each of these measures offers a different approach to improving fish passage. Adaptive 

management measures are considered necessary to meet and address any unforeseen scenarios 

that would result in reduced performance or an effectiveness and efficiency resulting in less than 

restoration goals. Future information on fish passage performance and hydraulic conditions will 

need to be collected, evaluated, and used in selecting adaptive measures that fit into and meet the 

goals of the Plan. Monitoring and effectiveness studies have shown that a majority of the 

American shad and river herring entering the fishways do so during periods of lower flow (FLA 

(2012 FLA, Exhibit E, Section 3.3 Fish Passage for Migratory Species). Operational 

enhancements, such as modification of turbine operations or adjustments to minimum flows, may 

therefore be the most cost effective way to address poor fish passage performance. Including an 

AWS in the EFL construction would increase the attraction flow and improve the Project’s fish 

passage efficiency if attraction to the EFL continues to be an issue. If EFL efficiency is an issue, 

design and operation reviews have shown that the existing cycle time of the EFL is no faster than 

one lift every 20 minutes. Changing out motors, pulleys, and other parts that limit the cycle time 

appears to be a low cost alternative to double capacity should the lift cycle time be able to be 

reduced to 15 minutes or less. Finally, if ability to get to the fish passage entrances proves to be 

an issue, channel modifications may amend this issue

9. Preliminary Reservation of Authority to Prescribe Fishways

In order to allow for the timely implementation of fishways, including effectiveness measures, 

the Department proposes that it request that the Commission include the following condition in 

any license(s) it may issue for the Project:

Pursuant to section 18 of the Federal Power Act, the Secretary of the Interior herein exercises his 

authority under said Act by reserving that authority to prescribe fishways during the term of these 

licenses.
APPENDIX G

Water Quality Certification – Muddy Run Pumped Storage Project
COMMONWEALTH OF PENNSYLVANIA

DEPARTMENT OF ENVIRONMENTAL PROTECTION

WATER QUALITY CERTIFICATION

FOR MUDDY RUN PUMPED STORAGE PROJECT

AND RELATED MITIGATION

FERC PROJECT NO. P-2355-018

EA 36-033:EXELON GENERATION COMPANY, LLC,

Colleen E.Hicks

Manager Regulatory and Licensing, Hydro

Exelon Generation Company, LLC

300 Exelon Way

Kennett Square, PA 19346

Drumore, Martic and Peach Bottom Townships

York and Lancaster Countys

United States Army Corps Of Engineers, Baltimore District

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Run project not in conformity with the plans approved by the FERC shall be made to any

project works constructed under the Federal Power Act without the prior approval or

authorization ofthe FERC.

D. Resource Agencies —"Resource Agencies" shall mean the DEP,

Pennsylvania Fish and Boat Commission ("PFBC"),Pennsylvania Department of

Conservation and Natural Resources ("DCNR"), Susquehanna River Basin Commission

("SRBC"),Maryland Department ofNatural Resources ("MDNR"), and United States

Fish and Wildlife Service ("USFWS").

E. General Requirements

1. The Muddy Run project shall at all times be subject to inspection

by representatives of DEP. DEP reserves the right to require such operational and

structural changes as may be considered necessary to assure compliance with the Federal

Water Pollution Control Act ("Clean Water Act"), the Pennsylvania Clean Streams Law,

the Dam Safety and Encmachments Act, and other appropriate requirements of state law.

Subject to applicable law, DEP further reserves the right to alter this certification for

failure to comply with the Clean Water Act and/or appropriate requirements ofthe state

law, an administrative order of DEP, or a term or condition ofthis certification.

2. Any additional information or modifications to any plans or

schedules required under this certification requested by the DEP shall be submitted

within the time frame established by the DEP in writing.

F. Reasonable Assurance of Compliance —DEP supports issuance of a 46

year license for the project. Because certain conditions ofthis certification expire in

2030, because of changes in the characteristics ofthe Susquehanna River that will occur

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by 2030, and because the FERC licenses for the Holtwood Hydroelectric Facility and the

Safe Harbor Hydroelectric Facility expire in 2030, this certification will be revised in

2030, as necessary to address demonstrated project impacts and subject to the provisions

ofthis certification, to establish requirements consistent with Section 401 ofthe Clean

Water Act, 33 U.S.C Section 1341.

III. FISH PASSAGE

General Requirements

Fish Passage Operating Procedures ("FPOP")

a. By January 15, 2015, EXELON shall submit a FPOP to the

DEP for review and approval. The FPOP will describe

existing baseline operations during fish passage season,

including schedules for routine maintenance, procedures

for routine operation (including: seasonal and daily periods

of operation, pump and turbine operations), sequencing of

pump and turbine start-up and operation, procedures for

monitoring and reporting fiows, procedures for monitoring

and reporting on the operation ofthe facility, procedures

for start-up and shut-down, and procedures for use in case

of emergencies and project outages significantly affecting

the conditions ofthis certification.

EXELON shall implement the FPOP consistent with the

approval ofthe DEP. EXELON shall provide written

documentation to the Resource Agencies that operational

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personnel have reviewed and understand the FPOP signed

by the operations manager ofthe Project.

c. Copies ofthe approved FPOP and all modifications will be

provided to the Resource Agencies.

By December 31 of each year, EXELON shall provide an

annual report to the Resource Agencies detailing: the

implementation ofthe FPOP, including any deviations from

the FPOP and a process to prevent those deviations in the

future; any proposed modifications to the FPOP, or in the

case of emergencies or project outages, the steps taken by

EXELON to minimize adverse effects on fisheries

including any proposed modifications to those steps to

further enhance their effectiveness in the future. EXELON

shall offer to meet with the Resource Agencies by January

31 of each year unless a different date is mutually agreed

upon by EXELON and the Resource Agencies. Any

required modifications to the FPOP shall be submitted to

the Resource Agencies within 45 days ofreceipt of a

request for the modification unless a longer period is

approved by the DEP. The modifications to the FPOP shall

be implemented consistent with the approval ofthe DEP.

In the event EXELON fails to submit the modifications as

required by this paragraph, the DEP, in consultation with

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the other Resource Agencies, may establish modifications

and EXELON shall implement the modifications consistent

with the approval ofthe DEP.

American Shad Passage

Upstream Shad Passage

Cooperation with Holtwood. Ifthe Holtwood

Hydroelectric Facility fails to meet its Tier I upstream shad

passage target described and included in the 401 Water

Quality Certification for the Amended Holtwood

Hydroelectric Facility, and DEP determines that

EXELON's operation ofthe Muddy Run Project is a

proximate cause of Holtwood failing to meet the Tier I

target, EXELON shall meet with the Resource Agencies to

establish snd implement a plan and schedule for a radio

telemetry study or equivalent (Tier II Study) ofAmerican

shad passage and behavior within the Muddy Run project

boundary. This meeting shall occur within one month of

the DEP's determination that Holtwood failed to meet its

Tier I upstream shad passage target or such longer time as

established by the DEP in writing.

Evaluation of Muddy Run Shad Passage. IfEXELON is a

proximate cause of Holtwood's failure to meet its Tier I

upstream shad passage target, EXELON shall develop a

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radio telemetry study plan and schedule or equivalent to

determine: (1)the percentage of American shad that enter

Muddy Run project at the northern tip of Sicily Island area

and subsequently exit the Muddy Run project area at the

southern tip of Deepwater Island; and (2) any delay or

impedance of shad passage attributable to the

redevelopment ofthe Holtwood Facility. EXELON shall

coordinate development ofthis plan with the Holtwood

Hydroelectric Facility and the Conowingo Hydroelectric

Facility. The radio telemetry study shall be designed to

insert the transmitter at the Conowingo facility or at such

other location(s) approved by the DEP.

Within two months ofthe meeting described in Paragraph

III.B.l.a.or such longer period approved by the DEP in

writing, EXELON shall submit the fish passage study plan

and schedule to the Resource Agencies for review and

approval by DEP. EXELON shall implement the plan

according to the schedule therein and consistent with the

approval ofthe DEP. In the event EXELON fails to submit

the plan and schedule as required by this paragraph, the

DEP, in consultation with the other Resource Agencies,

may establish a plan and schedule and EXELON shall

implement that plan and schedule consistent with the

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approval ofthe DEP. EXELON shall continue

implementation of a fish passage study for a minimum of

four years or such other time period as required by the DEP

in consultation with the other Resource Agencies.

EXELON shall provide an annual report ofthe monitoring

results ofthe fish passage study by December 31st of each

year.

At the end ofthe four-year study period, or such longer

time as established by the DEP, ifthe results indicate that,

as a result of Muddy Run operations, less than 88% ofthe

American shad that enter the Muddy Run project waters at

the northern tip of Sicily Island exit the Muddy Run project

waters at the southern tip of Deepwater Island, EXELON

shall propose a plan and schedule for operational

modifications to enhance fish passage at the project.

EXELON shall not be responsible for mitigating any

impacts attributable to PPL Holtwood. This plan and

schedule shall be submitted to the DEP as an amendment to

the FPOP for the following year. EXELON shall

implement the plan and schedule consistent with the

approval ofthe DEP. In the event EXELON fails to submit

the plan and schedule as required by this paragraph, the

DEP, in consultation with the other Resource Agencies,

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may establish a plan and schedule and EXELON shall

implement that plan and schedule consistent with the

approval ofthe DEP.

The average ofthe two highest years in the monitoring

period will be used determine whether the 88% fish

passage percentage is achieved. IfEXELON implements

operational modifications, only those years following the

operafional modifications shall be considered to determine

whether the 88% passage percentage is achieved.

If at the end ofthe monitoring period, or such longer time

as established by the DEP, the results indicate that the

operational modifications have resulted in less than 88% of

the American shad that enter the Muddy Run project waters

pass through the Project, EXELON shall propose a plan

and schedule for mitigation, as defined in 25 Pa. Code

Section 105.1 for the failure to achieve the 88% fish

passage target. This mitigation shall be: (I)in addition to

the compensatory mitigation described in this certification;

and (2) reasonably related and proportional to the identified

impact. This plan and schedule shall be submitted to the

Resource Agencies within 6 months from the end ofthe

monitoring period. EXELON shall implement the plan and

schedule consistent with the approval ofthe DEP. In the

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event EXELON fails to submit the plan and schedule as

required by this paragraph, the DEP, in consultation with

the other Resource Agencies, may establish a plan and

schedule and EXELON shall implement that plan and

schedule consistent with the approval ofthe DEP.

Downstream Shad Passage

a. Consistent with the relicensing studies for Muddy Run, by

January 15, 2015, EXELON shall submit a plan and

schedule to provide for 95% survival ofthe juvenile

American shad and 80% survival ofthe adult American

shad that pass through the project area. The schedule shall

provide for full implementation ofthe plan by 2015.

EXELON shall implement the approved plan and schedule.

IfEXELON fails to submit the plan, the DEP shall develop

a plan and schedule, in consultation with the other resource

agencies, and EXELON shall implement that plan and

schedule.

By February 15, 2026 or such later date approved by the

DEP in writing, EXELON shall submit a plan to measure

the passage of American shad moving downstream past the

project to the DEP for approval ("Discrete Passage Study" ).

EXELON shall implement the plan to measure the passage

of American shad moving downstream past the project

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according to the schedule and consistent with the approval

ofthe DEP. In the event EXELON fails to submit the plan

and schedule required by this paragraph, the DEP, in

consultation with the other Resource Agencies, may

establish a plan and schedule and EXELON shall

implement that plan and schedule consistent with the

approval ofthe DEP.

EXELON shall, in accordance with the plan, conduct the

Discrete Passage Study. EXELON shall provide a report of

the Discrete Passage Study within 180 days ofits

completion or such later date approved by the DEP in

writing to the Resource Agencies.

Ifthe results ofthe Discrete Passage Study indicate that

EXELON can operate the Muddy Run project so that

EXELON achieves at least 95%passage ofthe juvenile

American shad and 80 %passage ofthe adult American

shad that pass through the project area based on the

likelihood of a shad being exposed to typical pumping

operations and becoming entrained, then EXELON shall

incorporate into the annual FPOP any required operational

measures or protocols to meet the established percentages.

These procedures will be subject to review at the annual

meeting for the FPOP.

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Ifthe results ofthe Discrete Passage Study do not indicate

that the project can be operated to achieve at least 95%

passage ofjuvenile American shad and 80% passage of

adult American shad based on the likelihood of a shad

being exposed to typical pumping operations and becoming

entrained, EXELON shall propose a plan and schedule for

mitigation, as defined in 25 Pa. Code Section 105.1,for the

failure to achieve the fish passage target or targets. This

mitigation shall be: (I)in addition to the compensatory

mitigation described in this certification; and (2) reasonably

related and proportional to the identified impact. This plan

and schedule shall be submitted to the Resource Agencies

within 6 months from the end ofthe monitoring period or

such later date approved by the DEP in writing. EXELON

shall implement the plan and schedule consistent with the

approval ofthe DEP. In the event EXELON fails to submit

the plan and schedule as required by this paragraph, the

DEP, in consultation with the other Resource Agencies,

may establish a plan and schedule and EXELON shall

implement that plan and schedule consistent with the

approval ofthe DEP.

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C. Eel Passage

l. Upstream Eel Passage

The terms and conditions ofthe EXELON American Eel Passage

Plan for the Muddy Run Pumped Storage Hydroelectric Project (P-2355-018), attached

hereto as Appendix 1, are incorporated as iffully set forth herein.

Downstream Eel Passage

a. The trigger date for initiation of downstream eel passage

studies shall be the date on which the DEP, in consultation with

the other Resource Agencies, determines that available data

indicates that eels are present upstream ofthe project or other

upstream areas in numbers appropriate to require downstream

eel passage. This trigger date shall not occur prior to October

1, 2026 in order for the trapping and transport program to have

sufficient time to reestablish a significant eel population.

b. EXELON shall achieve at least 85% eel passage through the

project area based on the likelihood of an American eel being

exposed to typical pumping operations and becoming

entrained.

c. Within six months ofthe trigger date in Paragraph (a), or such

later date approved by the DEP in writing, EXELON shall

submit a plan to conduct a passage study to the Resource

Agencies. The plan shall be designed to demonstrate continued

compliance with the 85% fish passage target. The plan shall

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include radio telemetry studies or such other studies approved

by the DEP in consultation with the other Resource Agencies.

EXELON shall implement the plan according to the schedule

consistent with the approval ofthe DEP. In the event

EXELON fails to submit the plan and schedule as required by

this paragraph, the DEP, in consultation with the other

Resource Agencies, may establish a plan and schedule and

EXELON shall implement that plan and schedule consistent

with the approval ofthe DEP.

d. The study shall be initiated within 1 year ofthe trigger date

unless a different time frame is approved by the DEP in

writing. EXELON shall provide a report ofthe study results

within 180 days ofthe date of completion ofthe study.

e. Ifthe results of a discrete passage study indicate that EXELON

can operate the project so that EXELON achieves at least 85%

passage ofthe American eel that pass through the project area

based on the likelihood of an American eel being exposed to

typical pumping operations and becoming entrained,

EXELON shall incorporate into the FPOP any operational

measures needed to meet this percentage. These procedures

will be subject to review at the annual FPOP meeting.

f. Ifthe results ofthe studies do not indicate that the project can

be operated to achieve at least 85% passage ofAmerican eel

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based on the likelihood of an American eel being exposed to

typical pumping operations and becoming entrained, EXELON

shall propose a plan and schedule for mitigation, as defined in

25 Pa. Code Section 105.1,for the failure to achieve the 85'/o

eel passage target. This mitigation shall be: (1)in addition to

the compensatory mitigation described in this certification; and

(2) reasonably related and proportional to the identified impact.

This plan and schedule shall be submitted to the Resource

Agencies within 6 months from the end ofthe monitoring

period or such later date approved by the DEP in writing.

EXELON shall implement the plan and schedule consistent

with the approval ofthe DEP. In the event EXELON fails to

submit the plan and schedule as required by this paragraph, the

DEP, in consultation with the other Resource Agencies, may

establish a plan and schedule and EXELON shall implement

that plan and schedule consistent with the approval ofthe DEP.

D. Resident Fish Passage

1. Resident fish species include all fish species that occur in the

Susquehanna River excluding anadromous and catadromous fish.

2. From 2015 through 2030, EXELON shall implement the

mitigation measures described in Section VI to compensate for the entrainment of

resident fish species.

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IV. DISSOLVED OXYGEN ("DO")

A. Dissolved Oxygen Limitation.

l. EXELON shall operate the project in such manner that it does not

cause a violation ofthe dissolved oxygen criteria in the DEP water quality standards

(currently a minimum daily average dissolved oxygen concentration of 5 mg./l. and a

minimum of 4 mg./l.) at a location downstream of Muddy Run.

2. To assess compliance with Section IV. A. l. above, EXELON

shall, at DEP's request but no earlier than November 1, 2027 submit a DO monitoring

plan to the DEP. The plan shall propose a plan and schedule for monitoring dissolved

oxygen in the Conowingo Reservoir below the project during the months of April

through September for a period sufficient to characterize the impact ofthe project

operations on DO levels. Appropriate flow and temperature criteria suitable to trigger the

two year period will be developed in consultation with DEP. Such studies will be

developed afler consultation with the owner ofthe upstream Holtwood Project such that

any water quality impacts ofthe Muddy Run facility can be isolated. The plan shall

include data collection, analysis and reporting.

3. EXELON shall implement the plan and schedule as approved by

the DEP.

4. Ifthe monitoring conducted under the plan identifies violations,

defined as meeting less than 99io ofthe daily average or instantaneous standards (or the

alternative regulatory standard in place at the time ofthe study), resulting from operation

ofthe project, EXELON shall, within 30 days, consult with the DEP and within 90 days

submit a plan to resolve any DO violations resulting from operation ofthe project.

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5. In the event EXELON fails to submit the DO monitoring plan as

required bySection IV. A. 2., the DEP, in consultation with the other Resource Agencies,

may establish a plan and EXELON shall implement the plan consistent with the approval

ofDEP.

V. ENDANGERED SPECIES AND SPECIES OF SPECIAL CONCERN

A. Once every 10 years throughout the term ofthe license or such longer

period approved by the DEP in writing, EXELON shall conduct an evaluation of all state

and federal endangered or threatened species that may be present within the project

boundary.

B. Where that evaluation identifies the presence, critical habitat, or critical

dependence of endangered species, EXELON shall propose a plan and schedule to the

Resource Agencies to ensure protection ofthe endangered or threatened species within

180 days from completing the evaluation. EXELON shall implement the plan and

schedule as approved by the DEP.

C. In the event EXELON fails to submit the plan and schedule as required by

Section V. B.,the DEP, in consultation with the other Resource Agencies, may establish

a plan and schedule and EXELON shall implement that plan and schedule consistent with

the approval ofthe DEP.

VI. COMPENSATORY MITIGATION

A. Habitat Improvement Projects

1. By October 1 of each year from 2014 through 2030, EXELON

shall provide a total of FIVE HUNDRED THOUSAND DOLLARS ($500,000.00)

annually in compensatory mitigation to the Lancaster County Conservation District

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("LCCD"),the York County Conservation District ("YCCD")and the PFBC, or to such

other conservation district, resource agency or 501(c)(3)organization as directed by the

DEP, for the implementation of agricultural pasture and barnyard best management

practices to address sediment introduction and other habitat improvement projects

including small dam removals ("HIPs").

2. This annual compensatory mitigation shall be by corporate checks,

or the like, one made payable to the LCCD in the amount of TWO HUNDRED

TWENTY FIVE THOUSAND DOLLARS ($225,000.00), one made payable to the

YCCD in the amount of TWO HUNDRED TWENTY FIVE THOUSAND DOLLARS

($225,000.00) snd one made payable to the PFBC in the amount of FIFTY THOUSAND

DOLLARS ($50,000.00)for HIP funding in Lancaster or York Counties or in such other

combination or to such other entities as the PADEP shall direct. In addition, by March 1,

2014, EXELON shall provide a total FIFTY THOUSAND DOLLARS ($50,000) to the

PFBC to be used for HIPs in Lancaster and York Counties. EXELON and DEP shall

receive from LCCD, YCCD and PFBC an annual accounting of fund expenditures. The

funds shall be deposited by the LCCD, the YCCD and the PFBC into a special nonlapsing interest bearing account established and to be used only for the HIPs required by

this Water Quality Certification ("Exelon HIP Funds" ). Funds provided to the PFBC

shall be used solely for dam removal pmjects.

DEP shall ensure that each project proposed by the LCCD, the YCCD and the

PFBC shall be submitted to the DEP South-central Regional Office Waterways snd

Wetlands Program Manager, or the successor position, for approval. No single project

shall receive more than $75,000.00 in compensatory mitigation funding from the Exelon

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HIP Fund. Funding priority shall be given for projects that include stream forested

buffers of at least 50 feet in width and wetland creation projects. Project funding shall

not include any indirect administrative costs and, except where specifically authorized by

the DEP, shall not include direct administrative costs. In no case shall direct

administrative costs be greater than 5% ofthe project funding. At EXELON's option,

and subject to land owner approval, for each project signage shall be displayed

acknowledging EXELON's funding ofthe habitat improvement.

B. Flow Modeling

EXELON shall provide the version ofthe Lower Susquehanna River OASIS

Model to the Susquehanna River Basin Commission as provided in the "Letter

Agreement Addressing Exelon's Provision of an OASIS Model to SRBC"dated

November 19, 2013 and attached to this certification as Appendix 2.

Scott Williamson

Program Manager

Waterways and Wetlands Program

Date

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