# Presentation: 674200

## Evaluation of Mitigation Effectiveness at Hydropower Projects:  Fish Passage

**James M. Loar**
**Glenn F. Cada**
***Environmental Sciences Division***
***Oak Ridge National Laboratory***
**FERC Fish Passage Workshop**
**Alden Research Laboratory**
**Holden, MA**
**November 13, 2003**

## Outline of Presentation

**Introduction**
**Background**
**Purpose of study**
**Approach**
**Information sources**
**Description of database**
**Results**
**Measuring effectiveness**
**Upstream Fish Passage**
**Characterization**
**Effectiveness**
**Downstream Fish Passage**
**Characterization**
**Effectiveness**
**Effectiveness Monitoring Plans**
**Conclusions and Recommendations**
**Monitoring**
**Mitigation**

## Background

**Evaluation of mitigation effectiveness was included in the FERC strategic plan for complying with the Government Performance and Results Act of 1993**
**Present study is one of several FERC studies to evaluate the effectiveness of mitigation requirements included in FERC licenses**
**Shoreline management**
**Water quality**
**Fish passage**
**Recreation****	**

## Purpose of Study

**Assess the effectiveness of mitigation measures for upstream and downstream fish passage at projects licensed between 1987 and 2001**
**Improve FERC internal practices by ensuring that mitigation measures are both necessary and effective**

## Information Sources

**Primary:  FERC eLibrary database **
**(formerly FERRIS)**
**Effectiveness monitoring plans and reports submitted by licensees**
**Orders issued by Commission**
**Comment letters from resource agencies**
**Secondary:  Previous mitigation studies**
**DOE (1991, 1994)**
**Peer-reviewed journal articles**

## Description of Database:Number of Projects

**213 projects with at least one fish passage requirement**
**Comprised 66% of the 324 projects that were    licensed during the period 1987-2001**
**123 of the 213 projects had only the reservation of authority (Federal Power Act, Section 18)**
**90 projects consisting of 108 developments (=dams) constituted the actual database available for analysis**

## Geographical distribution of 213 projects  with at least one license article that addressed fish passage

## Regional summary of 108 hydropower developments with fish passage requirements in addition to Section      18 authority

| Region | No. of
 Projects | No. of
 Projects with 
Settlement 
Agreements | FISH  PASSAGE  REQUIREMENTS |  |  |  |
| --- | --- | --- | --- | --- | --- | --- |
|  |  |  | Upstream
Only | Downstream
Only | Upstream and
Downstream | Effectiveness
Monitoring |
| Northeast
(CT, MA, ME,
NH, NY, VT) | 59 | 25 | 6 | 27 | 26 | 45 |
| North Central
(MI, WI) | 30 | 25 | -- | 6 | 24 | 17 |
| Northwest
(AK, CA, ID,
OR, WA) | 16 | 4 | 5 | 4 | 7 | 12 |
| Southeast
(GA,VA, WV) | 3 | 1 | 1 | -- | 2 | 2 |
|       Total | 108 | 55 | 12 | 37 | 59 | 76 |

## Measuring Effectiveness	

**Used proportion of fish passed upstream or downstream**
**Requires an estimate of the population available for passage**
**Number of radiotagged fish released**
**Number of fish passed at downstream dam**
**Radiotagging most commonly employed to assess effectiveness of downstream fish passage**

## Characterization of Upstream Fish Passage Facilities

**Mitigation required at 71 of the 108 developments (66%)**
**Only 40% of the fish passage facilities are installed (and 71% of these are located in the Northeast)**
**Northeast and Northwest regions together account for 94% of the installed upstream fish passage facilities**
**Most common installed facilities are lifts/locks and Denil fishways in the Northeast and pool-weir fishways in the Northwest**

## Effectiveness of Upstream Fish Passage

**Adequate data to measure effectiveness were available for 3 of the 108 developments, all in the Northeast**
**No facilities installed at 52% of the developments**
**No effectiveness monitoring required at another 19%**
**5 of the 108 developments had fish counts but no estimate of the population available for passage**
**Effectiveness ranged from 45 to 67% for 3 anadromous species, based on counts at adjacent dams or mark-recapture study**
**All three facilities were lifts or locks**
**Effectiveness values are within the range stipulated in the management plan for American shad in the Connecticut River basin**

## Characterization of Downstream Fish Passage Facilities

**Mitigation required at 96 of the 108 developments (89%)**
**Only 41% of the fish passage facilities are installed (and 76% of these are located in the Northeast)**
**Northeast and Northwest regions together account for 91% of the installed downstream fish passage facilities**
**Most common type of facility (installed and uninstalled) in both the Northeast and Northwest is a sluiceway**

## Effectiveness of Downstream Fish Passage

**Adequate data to measure effectiveness were available for 11 of the 108 developments**
**Results available from 28 studies (93% in Northeast)**
**Radiotagging of Atlantic salmon smolts used to assess effectiveness at 7 of the 11 developments**
**Surface collection with conveyance below the dam was evaluated in 14 of the 28 tests                (4 developments)**
**Same species and similar methods used**
**Effectiveness  ranged from 17 to 78% across projects**
**Effectiveness highly variable between years at same project (e.g., 17-59% over 6 years; 17-63% over 4 years)**

## Effectiveness of Downstream Fish Passage (cont’d)

**Variability in river flow influenced results**
**Studies scheduled to avoid periods of spill where possible**
**Bypass effectiveness increased with reduced generating flow (bypass:intake flow ratio important)**
**Other methods of downstream fish passage were evaluated, but data on effectiveness were limited**
**Effectiveness of spill reached 100% following continuous design modifications over a 3-year period**
**Maximum effectiveness of sluices with louvers (72%) exceeded that of sluices without louvers (27%)**
**Effectiveness of angled bar racks not quantitatively assessed with anadromous species**

## Effectiveness Monitoring Plans

**Requirement for 76 of the 108 developments (70%)**
**Emphasis on monitoring to determine mitigation effectiveness is relatively recent (past 10-15 years)**
**Requirement has regional focus that reflects the importance of anadromous fish passage**
**76% of developments in Northeast**
**75% of developments in Northwest**

## Conclusions

**Effectiveness has been quantitatively evaluated at relatively few projects**
**Most (at least 70%) licenses require effectiveness monitoring**
**Technology advancement depends upon knowledge gained from monitoring effectiveness of existing facilities**
**Criteria to assess the success of fish passage mitigation were generally not available**
**Greater variability in the effectiveness of downstream vs. upstream fish passage, reflecting the importance of flow (bypass, generation, spill) as a factor influencing downstream fish passage effectiveness**
**Upstream fish passage is a mature, well developed technology, but downstream fish passage remains more experimental in approach**

## Recommendations

_**Monitoring**_
**Requirements for fish passage should include an effectiveness monitoring plan**
**Duration of monitoring should be defined**
**Can use radiotagging to test effectiveness for    2-4 years, depending upon flow conditions**
**May want to continue counts of upstream fish passage (i.e., “monitoring only”) and report annually**

## Recommendations

_**Mitigation**_
**Additional information should be obtained on the most effective measures for downstream fish passage**
**Field applications of new technologies**
**Passage of resident fishes **
**Need well-defined performance criteria to provide an unambiguous measure of the success of fish passage mitigation **