Integrated Water Quality Assessment 

for Florida: 

2008 305(b) Report 

and 303(d) List Update

October 2008

Florida Department of Environmental Protection 

Division of Environmental Assessment 

And Restoration

Bureau of Watershed Management
2008 Integrated Water Quality Assessment for Florida

ii

TABLE OF CONTENTS

Executive Summary.................................................................................ix

Chapter 1: Introduction ...........................................................................1

Purpose and Contents.............................................................................................. 1

Federal Assessment and Reporting Requirements ............................................... 1

Integrating the Federal Requirements into Florida’s Watershed 

Management Approach.................................................................................. 3

Chapter 2: Background Information.......................................................4

Overview.................................................................................................................... 4

Population....................................................................................................................... 6

Climate ............................................................................................................................ 6

Surface Water and Ground Water Resources ........................................................ 7

Streams and Rivers........................................................................................................ 7

Lakes............................................................................................................................... 8

Estuaries and Coastal Waters ....................................................................................... 9

Wetlands ........................................................................................................................10

Aquifers and Springs ....................................................................................................10

Hydrogeology.......................................................................................................... 11

Surface Water................................................................................................................11

Ground Water ................................................................................................................12

Surface Water–Ground Water Interactions..................................................................12

Water Pollution Control Programs ........................................................................ 13

Florida’s Water Resource Management Program .......................................................13

Florida Water Plan...................................................................................................13

Overview of Surface Water Protection Programs .......................................................14

Water Quality Standards Program...........................................................................14

Watershed Management Approach .........................................................................15

Total Maximum Daily Load Program........................................................................17

Surface Water Improvement and Management Program.........................................18

Point Source Control Program.................................................................................19

Healthy Beaches Program.......................................................................................21

Nonpoint Source Management Program .................................................................22

Atmospheric Deposition Reduction Strategies.........................................................24

Overview of Ground Water Protection Programs........................................................26
2008 Integrated Water Quality Assessment for Florida

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Permitting Programs................................................................................................26

Underground Injection Control.................................................................................26

Delineation Program................................................................................................26

Wellhead Protection ................................................................................................27

Source Water Assessment and Protection Program................................................27

Watershed-based Monitoring and Reporting ...........................................................28

Springs Initiative......................................................................................................29

Coordination with Other State, Tribal, and Local Agencies .......................................30

Results of Florida’s Surface Water Protection Programs ................................... 32

Nature and Extent of Nonpoint Source Pollution........................................................33

Recommended Nonpoint Source Programs................................................................33

Costs and Benefits of Implementing Florida’s Surface Water 

Protection Programs To Meet the Clean Water Act’s Objectives........................33

Clean Water Act State Revolving Fund Program.....................................................35

Construction Grants Program..................................................................................36

Section 319(h) Grant Funds ....................................................................................36

TMDL Water Quality Restoration Grants .................................................................36

Special State Concerns and Recommendations.................................................. 37

Concerns........................................................................................................................37

Recommendations ........................................................................................................37

Chapter 3: Surface Water Monitoring and Assessment......................40

Florida’s Surface Water Monitoring Program....................................................... 40

Background ...................................................................................................................40

Florida’s Integrated Water Resources Monitoring Program.......................................43

Element 1: Monitoring Objectives ...........................................................................45

Element 2: Monitoring Strategy ..............................................................................45

Element 5: Quality Assurance ................................................................................46

Element 6: Data Management................................................................................47

Element 9: Program Evaluation ..............................................................................47

Element 10: General Support and Infrastructure Planning......................................48

Evolving Approaches to Monitoring .........................................................................48

Surface Water Assessment.................................................................................... 49

Statewide Probabilistic Assessment (Tier 1)...............................................................49

Update 2006–08......................................................................................................49

Analytes ..................................................................................................................50

Monitoring Program Strategy for All Tiers of Monitoring...........................................51

Trend Monitoring .....................................................................................................51

Statewide Basin Assessment (Tier II) ..........................................................................54

Approach to the Comprehensive Assessment: Sections 305(b) and 303(d) ...........54

Determining Attainment of Designated Use(s).........................................................58

How Data Are Identified and Evaluated ...................................................................58
2008 Integrated Water Quality Assessment for Florida

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How Data Are Used To Make Attainment Determinations .......................................64

Results of Statewide Basin Assessments................................................................64

Summaries of Designated Use Support for Rivers/Streams, Lakes, 

Estuaries, and Coastal Waters .........................................................................65

303(d) List of Verified Impaired Waters ...................................................................68

Delisting ..................................................................................................................68

Status of Total Maximum Daily Load Development .................................................70

Trend Analysis for Rivers/Streams, Lakes, Estuaries, and Coastal Waters .............74

Special Focus: Lake Issues....................................................................................75

Drinking Water.........................................................................................................76

Freshwater, Estuarine, and Marine Sediment Contamination ..................................78

Public Health Concerns and Programs................................................................. 80

Drinking Water...............................................................................................................80

Bacterial and Mercury Contamination .........................................................................81

Harmful Algal Blooms...................................................................................................81

Blue-green Algae.....................................................................................................81

Pfiesteria .................................................................................................................83

Red Tide..................................................................................................................83

Wetlands Program .................................................................................................. 83

Wetlands Inventory and Wetlands Protection.............................................................83

Major Wetland Systems...........................................................................................83

Historical Wetlands Coverage in Florida..................................................................84

Development of Wetlands Water Quality Standards ................................................85

Integrity of Wetlands Resources..............................................................................85

Wetlands Management and Protection....................................................................85

Chapter 4: Ground Water Monitoring and Assessment......................91

Summary of Ground Water Monitoring Programs ............................................... 91

FDEP-maintained Ground Water and Springs Monitoring Programs ........................92

Potable Water Monitoring by FDOH/FDEP Water Supply Restoration 

Program ..................................................................................................................92

Public Water System (PWS) Monitoring ......................................................................93

Monitoring of Discharges to Ground Water.................................................................93

Summary of Ground Water Quality ....................................................................... 94

Overall Ground Water Quality ......................................................................................94

Ground Water Quality Issues and Contaminants of Concern, 

Including Public Health Issues..............................................................................96

Volatile Organic Compounds...................................................................................96

Synthetic Organic Chemicals/Pesticides................................................................100

Nitrates..................................................................................................................100

Primary Metals ......................................................................................................101

Radionuclides........................................................................................................102

Saline Water..........................................................................................................102
2008 Integrated Water Quality Assessment for Florida

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Trihalomethanes....................................................................................................102

Bacteria (Coliform) ................................................................................................103

Summary of Ground Water Contaminant Sources ............................................ 103

Petroleum Facilities.....................................................................................................103

Drycleaning Solvent Facilities....................................................................................104

Federal and State Waste Cleanup and Monitoring Sites ..........................................104

Nonpoint Sources .......................................................................................................104

Ground Water–Surface Water Interaction........................................................... 105

Setting and Pathways .................................................................................................105

Ground Water Parameters of Concern for Impaired Surface Waters.......................105

Springs and Spring-related Issues.............................................................................107

Chapter 5: Public Participation...........................................................112

Public Participation Process................................................................................ 112

Responsiveness Summary .................................................................................. 113

References ............................................................................................114

Appendices ...........................................................................................117

Appendix A. Discussion of Status Network Surface Water Indicators 

for Rivers and Lakes, and Ground Water Indicators............................... 117

Surface Water Indicators for Rivers and Lakes.........................................................117

Fecal Coliform Bacteria .........................................................................................117

Dissolved Oxygen .................................................................................................117

pH 117

Unionized Ammonia ..............................................................................................118

Chlorophyll a .........................................................................................................118

Trophic State Index ...............................................................................................119

Ground Water Indicators ............................................................................................119

Total Coliform Bacteria..........................................................................................119

Arsenic ..................................................................................................................120

Cadmium...............................................................................................................120

Chromium..............................................................................................................121

Fluoride .................................................................................................................121

Lead......................................................................................................................121

Nitrate-Nitrite .........................................................................................................122

Sodium..................................................................................................................122

Appendix B. Status Network Surface Water Methodology............................... 123

Monitoring Design.......................................................................................................123

Geographic Design .....................................................................................................124

Water Resource Types................................................................................................125
2008 Integrated Water Quality Assessment for Florida

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Lakes ....................................................................................................................125

Rivers, Streams, and Canals.................................................................................125

Appendix C. Impaired Surface Waters Rule Methodology for 

Evaluating Impairment for the Basin Assessments................................ 127

Aquatic Life Based Attainment...................................................................................127

Exceedances of Numeric Water Quality Criteria....................................................127

Exceedances of Nutrient Thresholds.....................................................................128

Exceedances of Biological Thresholds ..................................................................129

Lake Condition Index.............................................................................................130

Stream Condition Index.........................................................................................130

BioReconnaissance...............................................................................................131

Biological Integrity Standard..................................................................................132

Evaluation of Toxicity Data ....................................................................................132

Primary Contact and Recreation Attainment.............................................................132

Fish and Shellfish Consumption Attainment.............................................................132

Drinking Water Attainment and Protection of Human Health...................................133

Appendix D: Impaired Lakes in Florida, Group 1–5 Basins ............................. 134

List of Tables

Table 1. Florida Atlas ...............................................................................................................5

Table 2. Primary Coordination Mechanisms for Managing State, Regional, 

and Local Water Resources ............................................................................30

Table 3. Results of the Clean Watersheds Needs Survey for Florida.................................35

Table 4. Federal, State, Regional, and Local Agencies and Organizations 

that Carry Out Water Quality Monitoring in Florida.......................................41

Table 5. Summary of FDEP’s Monitoring Programs (Tiers I, II, and III) ..............................44

Table 6. Indicators Used for the Status and Trend Monitoring Networks ..........................52

Table 7. Temporal Variability Network Core and Supplemental Indicators........................53

Table 8. Water Quality Standards .........................................................................................54

Table 9. Categories for Waterbodies or Waterbody Segments in the 2008 

Integrated Report.............................................................................................55

Table 10. Basin Groups for Implementing the Watershed Management 

Cycle, by FDEP District Office ........................................................................57

Table 11. Basin Rotation Schedule for TMDL Development and 

Implementation ................................................................................................57

Table 12. Designated Use Attainment Categories for Surface Waters in 

Florida...............................................................................................................58

Table 13a. Data Used in Developing the Planning and Verified Lists, First 

Basin Rotation Cycle .......................................................................................62

Table 13b. Data Used in Developing the Planning and Verified Lists, 

Second Basin Rotation Cycle .........................................................................63
2008 Integrated Water Quality Assessment for Florida

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Table 14. Waters Assessed for the Statewide Basin Assessments, by 

Waterbody Type...............................................................................................64

Table 15. Size of Surface Waters Assigned to Each EPA Integrated Report 

Category ...........................................................................................................65

Table 16. Individual Designated Use Support Summary.....................................................66

Table 17. Size of Waters Impaired by Causes (Rivers/Streams, Lakes, 

Estuaries, and Coastal Waters).......................................................................67

Table 18. Numbers of Measurements and Impairment Status for the 

BioRecon and SCI, 1992–June 2004...............................................................73

Table 19. Trends in Water Quality for Rivers/Streams, Lakes, Estuaries, 

and Coastal Waters, 1997–2007 ......................................................................74

Table 20. Trophic Status of Significant Publicly Owned Lakes ..........................................75

Table 21. Total Miles of Rivers/Streams and Acres of Lakes/Reservoirs 

Designated for Drinking Water Use ................................................................76

Table 22. Miles of Rivers/Streams and Acres of Lakes/Reservoirs 

Designated for Drinking Water Use that Are Assigned to Each 

of the EPA’s Five Reporting Categories........................................................77

Table 23. Summary of Impaired River/Stream Miles and Lake/Reservoir 

Areas Overlapping Source Water Areas of Community Water 

Systems............................................................................................................78

Table 24. Historical Estimates of Wetlands in Florida, 1780–1980 .....................................84

Table 25. Acreage of Affected Wetlands Regulated by FDEP (since 2003) 

and the Water Management Districts (since 2000) ........................................86

Table 26. Mitigation Banks in Florida ...................................................................................89

Table 27. Summary of Ground Water Monitoring Programs and Data 

Sources ............................................................................................................91

Table 28. Indicator Analytes and Overall Ground Water Quality in Florida’s 

Aquifers ............................................................................................................95

Table 29. Summary of Contaminants of Concern for Aquifers Used as 

Potable Water Sources....................................................................................98

Table 30. Median Concentrations of Ground Water–Surface Water 

Constituents in Unconfined Aquifers (2000–07)..........................................106

Table 31. Reference Springs and Statewide Medians for Nitrate Nitrogen ......................108

Table A-1. Status Network Water Quality Standards for Ground Water...........................120

Table B-1. Basin Groups for Implementing the Watershed Management 

Cycle, by FDEP District Office ......................................................................124

Table B-2. Status Network Primary Index Periods.............................................................126
2008 Integrated Water Quality Assessment for Florida

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List of Figures

Figure 1. Springs of Florida...................................................................................................11

Figure 2. Agencies Responsible for Water Resource Coordination and 

Management in Florida....................................................................................32

Figure 3. Phosphorus Trends in Florida Waters, 1970–2005 ..............................................34

Figure 4. Five-Year Rotating Basin Cycle in FDEP’s Six Districts......................................49

Figure 5. Results of Florida’s Surface Water Quality Assessment for all 

Parameters (Excluding Mercury) ....................................................................71

Figure 6. Results of Florida’s Surface Water Quality Assessment for 

Mercury.............................................................................................................73

Figure 7. Statewide Summary of Contaminants of Concern in Potable 

Ground Water Sources....................................................................................97

Figure 8. Comparison of Nitrate Trends for Selected Springs (2000–06).........................109

Figure 9. Comparison of Recent and Historical Nitrate Concentrations in 

Florida Springs...............................................................................................110

Figure 10. Distribution of Nitrate Concentrations in Springs Monitored by 

FDEP...............................................................................................................111
2008 Integrated Water Quality Assessment for Florida

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EXECUTIVE SUMMARY

Introduction

Purpose and Contents. This report on water quality in Florida, prepared by the Florida 

Department of Environmental Protection (FDEP), provides an overview of Florida’s surface 

water and ground water quality and trends as of 2008. The report, which must be submitted to 

the U.S. Environmental Protection Agency (EPA) every two years, meets the reporting 

requirements of Sections 305(b) and 303(d) of the federal Clean Water Act (CWA). Under 

Section 305(b), each state must report to the EPA on the condition of its surface waters, and 

Section 303(d) requires each state to report on its polluted waterbodies (those not meeting 

water quality standards). Using the information from all the states, the EPA provides Congress 

with a broad-scale national inventory of water quality conditions and also develops priorities for 

future federal actions to protect and restore aquatic resources. 

Successes in Water Quality Protection. Florida has abundant, diverse water resources, 

which support various habitats, plants, and animals, as well as food crops, industry, tourism, 

and recreation. In addition, an enormous underground aquifer system supplies potable water to 

90% of the population.

Despite rapid population growth over the past 35 years, Florida has been very successful in 

protecting its water resources by reducing pollution from existing point and nonpoint sources. 

This has been accomplished by implementing new technologies, requiring better treatment of 

wastewater, reusing treated wastewater, eliminating many surface water discharges, and 

treating stormwater. The graph on the next page illustrates the success of the state’s 

programs.a

 a The points on the graph are annual averages of all surface water quality stations found in Florida STORET. They were first 

averaged by waterbody—approximately 2,200 streams, lakes, and estuaries for each year.

 It shows that after 1982, phosphorus levels decreased, because of regulations that 

eliminated many point sources and led to the reuse of treated domestic wastewater, and 

because of the implementation of stormwater treatment regulations.

Future Challenges. The close connection between surface and ground water, in combination 

with the pressures of continued population growth, accompanying development, and extensive 

agricultural operations, present Florida with a unique set of challenges for managing both water 

quality and quantity in the future.

Despite Florida’s successes in protecting its water resources, the graph on the next page also 

points to a potential problem that is emerging. After trending downward for 20 years, beginning 

in 2000 phosphorus levels again began moving upward, likely due to the cumulative impacts of 

nonpoint source pollution associated with increased population and development.

Increasing pollution from urban stormwater and agricultural activities is having other significant 

effects. In many springs across the state, for example, nitrate levels have increased 

dramatically (twofold to threefold) over the past 20 years, reflecting the close link between 

surface and ground water. Nitrate sources in ground water include the following:
2008 Integrated Water Quality Assessment for Florida

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• Excess fertilizer from agricultural operations (particularly high levels of nitrates

are found underneath intense, center-pivot agricultural operations associated 

with dairy farming; crops; and areas with wastewater reuse),

• Excess fertilizer from urban lawns and landscapes, and

• Excess nutrients leaching into ground water from septic tanks.

Surface Water Results

FDEP evaluated data from 6,300 waterbodies statewide against state water quality standards. 

There were sufficient data to evaluate (by area or length) 53% of the state’s rivers and streams, 

81% of its lakes, and 99% of its estuaries and coastal waters. Ninety different chemical and 

biological parameters were evaluated.

This report encompasses results from the completion of a 5-year cycle that evaluates water 

quality for the entire state—i.e., 20% of the state is assessed each year for 5 years. The figure 

on the next page shows that most surface water quality problems are found in highly urbanized 

central and south Florida (except for mercury contamination, which is statewide). Areas with 

intense agricultural and industrial use are also associated with poor water quality. Water quality 

in the northwest and west-central sections of the state is generally better than in other areas.

Of the waterbodies that were evaluated, poor water quality (for all causes except mercury) was 

found in 28% of the river and stream miles, 25% of the lake acres, and 59% of the square miles 

Phosphorus pollution peaks 

in early 1980s

0.04

0.05

0.06

0.07

0.08

0.09

0.10

0.11

1970 1975 1980 1985 1990 1995 2000 2005

phosphorus (mg/l)

Phosphorus 

pollution builds 

up in Florida 

waters

In 1982, Florida 

implements Stormwater 

Rule and no-discharge 

policy for point sources

Cumulative effects of 

nonpoint sources are 

driving phosphorus 

levels up again—TMDLs 

are seeking to address 

these impacts
2008 Integrated Water Quality Assessment for Florida

xi

of estuaries. To date, with 100% of the state evaluated, approximately 2,565 TMDLs will be

required for 1,688 Florida waters. Because TMDLs are developed for individual pollutants, a 

waterbody may have multiple TMDLs. To date, FDEP has developed, proposed, or adopted 

322 TMDLs for 166 waterbodies, and 3 Basin Management Action Plans (BMAPs) have been 

completed and adopted by Secretarial Order (for the Upper Ocklawaha River Basin, Orange 

Creek, and Long Branch).

The percentage of unpolluted waterbodies (not including mercury in fish) for each surface water 

classification was as follows:

• Class 1 waters (potable supplies), which supply about 13% of Florida’s drinking 

water: 16% of river/stream miles and 1% of lakes.

• Class II waters (shellfish propagation or harvesting): 4% of river/stream miles 

and 16% of estuarine square miles.

• Class III fresh waters (recreation, propagation, and maintenance of a healthy, 

well-balanced population of fish and wildlife): 9% of river/stream miles and 15% 

of lake acres.

• Class III marine waters (recreation, propagation, and maintenance of a healthy, 

well-balanced population of fish and wildlife): 18% of estuarine square miles 

and 63% of coastal square miles.
2008 Integrated Water Quality Assessment for Florida

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All estuaries and coastal waters have been tested for mercury levels in fish tissue, and 

consumption advisories have been established for a number of fish species. The figure below

shows the results for mercury only. Freshwater and marine TMDLs for mercury will be 

developed statewide and are due in September 2012.

Causes of Surface Water Impairment. Florida’s major pollution problems are caused by 

mercury in fish, low dissolved oxygen (DO), fecal coliform bacteria, and nutrients. Low DO is 

caused by natural conditions, hydrologic modifications, or pollution discharges.

Surface Water Quality Trends. Changes in water quality over time are an important indicator 

of the health of surface waters. Out of 823 rivers/streams, lakes, estuaries, and coastal waters 

evaluated from 1997 to 2007, about 54% were stable, about 22% were improving (in urban 

areas, due to improved wastewater and stormwater treatment), and about 24% were degrading 

(in agricultural areas, the Suwannee River Basin, and areas of urban growth).
2008 Integrated Water Quality Assessment for Florida

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Ground Water Results

Ground water, which provides more than 90% of Florida’s drinking water, is highly vulnerable to 

contamination in much of the state. Generally, the overall quality of the evaluated potable 

aquifers was good. However, a number of ground water issues should continue to receive 

attention.

The evaluation used historical ground water data from monitoring networks, private wells, and 

public water systems. The results were as follows:

• Volatile organics—Benzene most frequently exceeded its primary drinking water 

maximum contaminant level (MCL). Trichloroethene (TCE) was the second most 

frequently detected compound above its MCL in samples from public water systems 

and private wells, closely followed by tetrachloroethene. The greatest number of 

exceedances for volatile organics in public water systems was in the Ocklawaha Basin, 

and the greatest numbers of contaminated private wells were in the Lower St. Johns 

Basin and in the basins of west-central Florida. The detection of contaminants in 

private wells is in part a function of sampling density, and these areas were intensively 

sampled because of problems with leaking underground storage tanks.

• Pesticides (Synthetic Organic Chemicals)—In public water system samples, the 

greatest number of pesticide MCL exceedances were for lindane, toxaphene, and 

methoxychlor (mainly detected in the 1980s and since banned). Pesticides have 

historically been a more significant issue for private well owners in agricultural areas 

than for public water systems. In private wells, most exceedances were for another 

banned compound, ethylene dibromide (EDB), which was found in samples collected in 

the 1980s. More recent issues in private wells were identified for the agricultural 

chemicals bromacil and alachlor.

• Nitrates—Exceedances of the MCL for nitrate-nitrogen or nitrate+nitrite-nitrogen were 

found in samples from 148 public water systems and over 2,500 private wells, with the 

greatest number found in or near agricultural areas. Most private well exceedances 

were found in agricultural areas, with almost half of the total found in the ridge citrus–

growing area of the Kissimmee River Basin.

• Metals—Samples from public water systems have historically exceeded MCLs for one 

or more primary metals; however, some data, particularly for lead and cadmium, may 

not be valid because of the influences of metal piping and tanks used to transport and 

store water. In samples from private drinking water wells, exceedances were most 

frequent for arsenic and lead, with lead most often associated with plumbing or fixtures 

rather than ground water.

• Radionuclides—Most exceedances in samples from public water systems were found 

in the large phosphate-mining area of west-central Florida. Radioactivity is a natural 

characteristic of phosphate.

• Sodium—Most of the elevated sodium concentrations were found in public water 

systems in central and southwestern Florida, two areas where the intrusion and 

upwelling of saline waters are serious concerns due to heavy ground water use and 

drought conditions. Sodium is a key indicator of saline water influx.

• Trihalomethanes (THMs)—THMs are byproducts of the disinfection of water 

containing organic matter and are most often found in public water system samples. 

Most incidences of THMs exceeding primary MCLs were found in public water systems 

in the Middle St. Johns Basin and also in coastal areas of the state where shallower 

aquifer systems are being utilized.
2008 Integrated Water Quality Assessment for Florida

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• Bacteria—Bacterial contamination was an issue for monitoring well samples and is a 

common issue with water from private wells and water systems. Well contamination is 

typically from a localized source.

• Sources of Ground Water Degradation—The most significant sources were 

petroleum sites, drycleaners, hazardous waste sites, and nonpoint pollution. Point 

sources such as leaking underground storage tanks, drycleaners, and waste sites are 

most frequently associated with volatile organics contamination. Nonpoint sources 

such as citrus groves and other agricultural sites are the most common sources of 

nitrates and pesticides. Salinity (as sodium) is a result of local or regional overuse of 

the ground water resource and is a looming issue as growth and drought conditions 

coincide.

• Ground Water–Surface Water Interaction—Nutrients, dissolved oxygen, and iron 

were the ground water constituents most frequently identified with affected surface 

waters that exceed criteria. Ground water inflows account for most of the water in many 

Florida surface waters.

• Springs—Florida’s springs are unique water resources that represent the discharge of 

ground water to surface water. Spring systems are being threatened statewide by 

biological imbalances caused by excessive nutrients that are being delivered by ground 

water. Nitrate is the major indicator of nutrient enrichment.

Conclusion

The Florida Oceans and Coastal Council recently released the “Phase II-Florida’s Ocean and 

Coastal Economies Report,” (http://www.floridaoceanscouncil.org/meetings/files/2008/09-

30/Florida_Phase_II_Report.pdf) which reveals that Florida’s ocean and coastal resources (e.g., 

fishing, marine transportation, and tourism) were estimated to contribute $25 Billion and $562 

Billion to Florida’s Gross State Product in 2006. Sustaining the value of these resources is 

intimately linked to maintaining the quality of the aquatic environment. Water quality in Florida’s 

surface and ground water systems is being evaluated on a rotating basin approach, allowing 

greater monitoring and evaluation of the health of these resources. Tremendous progress has 

been made in addressing point and nonpoint pollution. However, as the state’s rapid population 

growth continues, the increasing amount of nonpoint source pollution (including urban 

stormwater), atmospheric deposition (including nutrients and mercury), and agricultural activities

remain a concern that needs further study and review. 
2008 Integrated Water Quality Assessment for Florida

1

CHAPTER 1: INTRODUCTION

Purpose and Contents

This report, Integrated Water Quality Assessment for Florida, provides an overview of Florida’s 

surface water and ground water quality and trends. Referred to as the Integrated Report 

because it fulfills the reporting requirements under Sections 305(b) and 303(d) of the federal 

Clean Water Act (CWA), the report must be submitted to the U. S. Environmental Protection 

Agency (EPA) every two years.

Chapter 1 of this report provides background information on the federal assessment and 

reporting requirements and how these requirements are integrated into Florida’s watershed 

management approach. Chapter 2 contains background information on the state’s population, 

surface water and ground water resources, climate, and hydrogeology. It also summarizes 

Florida’s major programs and activities to protect and manage water resources, and the results 

of these programs. Chapter 3 describes Florida’s approach to surface water monitoring,

presents significant surface water quality findings, and summarizes attainment of designated 

uses (i.e., functional classifications such as recreation, drinking water, and aquatic life) for rivers 

and streams, lakes, estuaries, and coastal waters. Long-term trends in surface water quality, 

public health and drinking water issues, and wetlands protection efforts are discussed. Chapter 

4 describes the state’s ground water monitoring program, presents significant ground water 

quality findings, summarizes ground water contaminant sources, and characterizes ground 

water–surface water interactions. Evaluating ground water resources is particularly important 

because 90% of the state’s drinking water supplies come from ground water. The Appendices 

provide background information and supporting data.

Federal Assessment and Reporting Requirements

Section 305(b) of the CWA requires states and other jurisdictions to submit biennial water 

quality reports to the EPA. These reports, referred to 305(b) reports, describe surface water 

and ground water quality and trends, the extent to which waters are attaining their designated 

uses (such as drinking water, recreation, and shellfish harvesting), and major impacts to surface 

water and ground water. Under Section 303(d) of the CWA, states are also required to identify 

waters that are not attaining their designated uses, submit to the EPA a list of these impaired 

waters (referred to as the 303[d] list because they are required under Section 303[d] of the 

CWA), and develop total maximum daily loads (TMDLs) for them. A TMDL represents the 

maximum amount of a given pollutant that a waterbody can assimilate and still meet its 

designated uses.

Water quality monitoring and data analysis are the foundation of water resource management 

decisions. The EPA and its state partners have worked together to develop an integrated 

305(b) and 303(d) assessment approach to address water quality monitoring strategies, data 

quality and data quantity needs, and data interpretation methodologies. This Integrated Report 

continues the consolidation and alignment of the 305(b) and 303(d) assessment and reporting 

requirements. It also includes Section 314 reporting on the status and trends of significant 

publicly owned lakes.
2008 Integrated Water Quality Assessment for Florida

2

The Integrated Report allows states to document whether water quality standards are being 

attained, documents the availability of data and information for each waterbody segment, 

identifies trends in water quality conditions, and provides information to managers in setting 

priorities for future actions to protect and restore the health of Florida’s aquatic resources. This 

comprehensive approach to assessment enhances Florida’s ability to track important 

programmatic and environmental goals of the CWA and ideally, speeds up the pace of 

achieving these goals.

Florida’s integrated approach to monitoring and assessment consists of three tiers: probabilitybased, basin-specific, and site-specific. Probabilistic assessments (Tier I) are used to develop 

statistical estimates of water quality across the entire state, based on a representative sample, 

and to examine changes in water quality and flow over time statewide. The use of probability 

assessments can eliminate the risk of generating a biased picture of water quality conditions 

statewide, provide information on changes in water quality and flow over time statewide, and 

provide a cost-effective benchmark of the effectiveness of Florida’s water quality program. The 

results can also provide information on whether it would be useful to target certain waters for 

further assessment, or if limited resources for water quality assessment can be used more 

effectively in other ways.

Basin-specific and stream-specific monitoring (Tier II) is used to carry out strategic monitoring to 

address gaps in data provided by other monitoring agencies, to address questions in specific 

basins and waterbody segments that are associated with determinations of waterbody 

impairment for the TMDL Program, and to obtain information on springs across the state. Sitespecific monitoring (Tier III) includes intensive surveys for TMDLs, monitoring for the 

development of water quality standards and site-specific alternative criteria, and fifth-year 

inspections for permit renewals for facilities that discharge to surface waters.

Placing each waterbody segment into one of five reporting categories, based on available data, 

is an essential part of the assessment. According to the EPA, this approach allows the states to 

document the attainment of applicable water quality standards and develop monitoring 

strategies that effectively respond to the needs identified in the assessment, while ensuring that 

the attainment status of each water quality standard applicable to a particular waterbody 

segment is addressed. The five broad categories are as follows:

• Category 1: All designated uses are supported; no use is threatened.

• Category 2: Available data and/or information indicate that some, but not all, of 

the designated uses are supported.

• Category 3: There are insufficient available data and/or information to make a 

use support determination.

• Category 4: Available data and/or information indicate that at least one 

designated use is not being supported or is threatened, but a TMDL is not 

scheduled for development.

• Category 5: Available data and/or information indicate that at least one 

designated use is not being supported or is threatened, and a TMDL is needed.
2008 Integrated Water Quality Assessment for Florida

3

Integrating the Federal Requirements into Florida’s 

Watershed Management Approach

For the 2008 305(b) report, the Florida Department of Environmental Protection (FDEP) has 

continued to move towards a comprehensive assessment by integrating the federal assessment 

and reporting requirements into its watershed management approach. The 1999 Florida 

Watershed Restoration Act (FWRA) directed FDEP to implement a comprehensive, integrated 

watershed approach to evaluating and managing cumulative impacts to the state’s waters. 

FDEP’s Division of Water Resource Management initiated the watershed management 

approach in 2000, through the Bureau of Watershed Management. 

To implement the watershed management approach, Florida’s 52 basins were divided into 29 

groups that are distributed among FDEP’s 6 districts. There are 5 basins each in the Northwest, 

Central, Southwest, South, and Southeast Districts, and 4 basins in the Northeast District. One 

basin is assessed in each district every year. Using a rotating basin management cycle, which 

ensures that each basin is assessed every 5 years, FDEP and local stakeholders assess 

individual basins, identify impaired waters requiring the development of TMDLs, and develop 

Basin Management Action Plans (BMAPs) to restore water quality. The order and specific time 

frame for evaluating each basin are based on a number of priority factors, including watersheds 

that contain surface water sources of drinking water, watersheds with more severe water quality 

problems, and watersheds where Surface Water Improvement and Management (SWIM) plans 

are proposed or under way.

The assessment, consisting of multiple phases, has been completed in all of the state’s basins 

(the Group 1–5 basins), and the scope of the 303(d) list submittal comprises these basins. As 

part of its watershed management approach, which rotates through all of the state’s basins over 

a five-year cycle, FDEP developed Verified Lists of impaired waters for the Group 1–5 basins in 

2002, 2003, 2004, 2005, and 2006, respectively. As required by Subsection 403.067(4), Florida 

Statutes (F.S.), the lists were then adopted by Secretarial Order. The resulting Verified Lists of 

impaired waters and waters to be delisted in those basins amend the 1998 303(d) list of 

impaired Florida waters maintained by the EPA. FDEP plans to submit annual amendments to 

its 303(d) list as part of the watershed management approach, and the watershed cycle will be 

repeated beginning with the Group 1 basins over the next year.

Florida continues to develop an integrated database of assessment information that reflects 

whether water quality standards are being attained. The Master List provided in the Water 

Quality Assessment Report for each basin provides detailed results of the assessment. The 

basin reports, as well as all of the Verified Lists and lists of waters to be delisted, are available 

at http://www.dep.state.fl.us/water/tmdl/index.htm.
2008 Integrated Water Quality Assessment for Florida

4

CHAPTER 2: BACKGROUND 

INFORMATION

Overview

Florida's 65,758 square miles support abundant, diverse natural resources. Some of these—for 

example, the Everglades—are found nowhere else. Florida also contains the only coral reef in 

the continental United States. The state has 11,761 square miles of surface water (ranking third 

in the country in total water area) and enormous supplies of fresh water in its underground 

aquifers. Florida depends on water resources in many ways—for example, for its $7 billion 

fishing and $32 billion tourism industries.

The pressures of population growth and its accompanying development are stressing the state’s 

freshwater, ground water, and saltwater resources. Although the state ranks twenty-second in 

the country in total land area, it currently ranks fourth in population, and that population 

continues to grow rapidly. Florida will soon be the third largest state. Most Floridians live in 

coastal areas where less fresh water is available, and about three-fourths of new Florida 

residents choose coastal locations for their new homes. As development continues, different 

users vie for water resources. Major challenges include maintaining overall water quality and 

supplies, protecting public health, satisfying competing and rapidly increasing demands for finite 

quantities of fresh water, minimizing damage to future water reserves, and ensuring healthy 

populations of fish and wildlife.

Despite the fact that water is plentiful in many areas, water quantity and quality are critical 

issues. In 1950, Florida’s population of 2.8 million used about 2.9 billion gallons per day (BGD) 

of fresh ground water and surface water. In 1995, that number had risen to 7.2 BGD, and 

consumption is projected to rise to 9.3 BGD by 2020. In many areas, surface water and ground 

water quality has been degraded by industrial, residential, and agricultural land uses. Many 

point sources of pollution such as sewage treatment plant discharges have been eliminated, but 

contamination from widespread, diffuse nonpoint sources such as urban development and 

agriculture remains a problem. Nitrate in ground water discharging from springs is a 

widespread concern.

Along the coasts, water quality in many estuaries has deteriorated, habitat losses have affected 

commercial and recreational fisheries, and sediments in many urban estuaries contain heavy 

metals and organic contaminants. Consumption advisories have been issued because tissues 

in a number of freshwater and saltwater fish species in many waters contain excessive 

concentrations of mercury. In Florida Bay, there have been algal blooms and extensive 

mangrove and seagrass die offs in recent years.

This chapter provides background information about Florida’s population, water resources, 

climate, and physical features. It also describes Florida’s Water Resource Management 

Program for protecting surface water and ground water.

Table 1 summarizes basic information on the state and its surface water resources.
2008 Integrated Water Quality Assessment for Florida

5

Table 1. Florida Atlas

2006 estimated population (U.S. Census Bureau) 18,089,888 people

Ranking by population among 50 states 4th largest

% change, April 1, 2000, to July 1, 2006 + 13.2%

Surface area 65,758 square miles

Ranking by land area among 50 states 22nd in size

Total water area 11,761 square miles

Ranking by total water area among 50 states 3rd largest

Number of U. S. Geological Survey hydrologic units 

(i.e., watersheds with hydrologic unit codes, or HUCs) 52

Total number of rivers and streams More than 1,700

Total number of river and stream miles 51,858 miles

Total river miles bordering other states 191 miles

Chattahoochee River 26 miles

Perdido River 65 miles

St. Marys River 100 miles

Total density of rivers/streams 0.89 miles/square mile

Longest river (entirely in Florida) St. Johns River (273 miles)

Largest discharge Apalachicola River (average of 

24,768 cubic feet per second [cfs])

Perennial streams 19,705 miles

Density of perennial streams 0.39 miles/square mile

Intermittent streams 2,956 miles

Density of intermittent streams 0.05 miles/square mile

Ditches and canals 25,909 miles

Density of ditches and canals 0.44 miles/square mile

Number of lakes, reservoirs, and ponds 7,712 (area greater than or equal to 10 acres)

Area of lakes, reservoirs, and ponds 1,529,280 acres

Area of largest lake Lake Okeechobee (435,840 acres)

Area of estuaries and bays 4,462 square miles 

Area of coastal waters 6,758 square miles

Area of freshwater and tidal wetlands 17,830 square miles

Prominent wetland systems

Everglades and Big Cypress Swamp, Green Swamp, 

Okefenokee Swamp, Big Bend coastal marshes, St. 

Johns River marshes

Area of islands greater than 10 acres 1,314 square miles

Number of known springs More than 700

Combined spring outflow 8 billion gallons per day

Largest spring Wakulla Springs (average discharge 

of 252 million gallons per day [MGD])

Number of first-order magnitude springs 

(flows greater than 64.6 MGD) 33
2008 Integrated Water Quality Assessment for Florida

6

Florida Population, 1990

Source: Fernald and Purdum, 1998

Photo: Florida Department of Commerce

Population

According to the U.S. Census Bureau, Florida’s population in 2006 was 18,089,888. Currently 

the fourth most populous state in the country, it is projected to be the third most populated in

approximately 4 years.

2

As the baby-boom generation (those born 

between 1946 and 1964) reaches retirement 

age, the numbers of elderly residents (65 

and over) are expected to accelerate rapidly 

in all states. In Florida, the proportion of 

elderly is projected to expand from 18.6%

in1995 to 26.3% in 2025. Florida had the 

country’s highest proportion of elderly in 

1995 and is also projected to have the 

highest proportion in 2025.

 Within the next two decades, the state’s total population is expected to 

increase by 7.2 million people, the ninth largest gain in the country. Florida is also expected to 

gain 1.9 million people through international migration between 1995 and 2025, the third largest 

net gain in the country.

The state has a number of large, expanding 

population centers, including southeastern 

Florida (Dade, Broward, and Palm Beach 

Counties), Jacksonville, Tampa–St. 

Petersburg, southwest Florida (from 

Sarasota to Naples), and Orlando. In 

contrast, other relatively large areas of 

Florida area sparsely populated.

Climate

The state’s climate ranges from a transitional zone between temperate and subtropical in the 

north and northwest, to tropical in the Keys. As a result, Florida's plants and animals are a mix 

of those from more temperate northern climates and those from the tropical Caribbean. Three 

hundred native trees and 3,500 vascular plants have been recorded. More than 425 bird 

species, about half the known species in the United States, can be seen in Florida.

Summers are long, with periods of very warm, humid air. Maximum temperatures average 

about 90° F., although temperatures of 100° F. or greater can occur in some areas. Winters are 

generally mild, except when cold fronts move across the state. Frosts and freezes are possible, 

but typically temperatures do not remain low during the day, and cold weather usually lasts no 

more than two or three days at a time.

Rainfall across the state varies with location and season. On average, more than 60 inches per 

year falls in the far northwest and southeast, while the Keys receive about 40 inches annually. 

This variability can create local water shortages. The heaviest rainfall occurs in northwestern 

Florida and in a strip 10 to 15 miles inland along the southeast coast.

 2 Vogel, April 2006.
2008 Integrated Water Quality Assessment for Florida

7

Florida’s Average Annual Rainfall, 1961–90

Source: Fernald and Purdum, 1998

Except for the northwestern part of the state, most of Florida has a rainy season and a relatively 

long dry season. In the peninsula, half the average annual rainfall usually falls between June 

and September. In northwestern Florida, a 

secondary rainy season occurs in late winter to 

early spring. The lowest rainfall for most of the 

state occurs in fall (October and November) and 

spring (April and May). The varying patterns of 

rainfall create differences in the timing of high 

and low discharges from surface waters.

An approximate diagonal line drawn from the 

mouth of the St. Johns River at the Atlantic 

Ocean to the boundary of Levy and Dixie 

Counties on the Gulf of Mexico depicts a climatic 

river basin divide. North and northwest of the 

divide, streams have high discharges in spring 

and late winter (March and April) and low 

discharges in the fall and early winter (October 

and November). A second low-water period 

occurs from May to June. South of the climatic 

divide, high stream discharges occur in 

September and October, and low discharges 

occur from May to June.

Surface Water and Ground Water Resources

Florida has 51,858 miles of streams and rivers (about half of which are ditches and canals). It 

contains more than 7,700 lakes greater than 10 acres in size, with a total surface area of 

1,618,368 acres. The state also has 4,460 square miles of estuaries and a coastline ranking 

second in length only to Alaska. A line running from the northeast corner of the state to Key 

West and back up to the northwest corner along the Gulf Coast would extend 1,300 miles. If the 

distance around barrier islands and estuaries were included, the line would stretch 8,460 miles.

Streams and Rivers

The state has more than 1,700 streams and rivers. Differences in climate, hydrogeology, and 

location all affect their water quality. The longest river entirely in the state is the St. Johns, 

which flows north as a recognizable stream about 273 miles from the St. Johns Marsh in 

northern St. Lucie County, to its mouth at Jacksonville. The river drains a land area equal to 

about one-sixth of Florida's surface. The Apalachicola River, in the Florida Panhandle, has the 

largest discharge flow, averaging almost 25,000 cubic feet per second. Its basin, draining over 

19,000 square miles, extends to north Georgia’s southern Appalachian Mountains. Also, in the 

Panhandle, spring discharges give rise to ground water rivers, where the ground water base 

flow comprises 80% of the rivers’ flow.

Florida has several types of natural river systems. In fact, most Florida rivers exhibit 

characteristics of more than one type of river system, either at different places along their length 
2008 Integrated Water Quality Assessment for Florida

8

or at different times of the year. The links between surface water and ground water can also 

affect natural systems. A good example is the Suwannee River, which originates in the 

Okefenokee Swamp as a blackwater stream and becomes spring fed south of Ellaville. During 

periods of high flow, it carries sand and sediments, behaving like a true alluvial stream. During 

low flow, however, the river’s base flow comes from underground springs. These variations in 

flow affect the downstream stretches of the river and the receiving estuary. Ground water has 

higher nitrate concentrations that can affect animals and plants downstream, while the sand and 

sediments carried by the river during periods of high flow have a different effect on biological 

life.

In north and northwest Florida, many rivers are alluvial. The Choctawhatchee, Apalachicola, 

and Escambia Rivers best represent this type. Common features include a well-developed 

floodplain, levees, terraces, oxbows, and remnant channels (sloughs) that parallel the active 

riverbed. Typically, because flows fluctuate more than with other types of rivers, habitats are 

more diverse.

There are many blackwater streams and rivers in Florida. Blackwater rivers usually have acidic, 

highly colored, slowly moving waters containing few sediments. These systems typically drain 

acidic flatwoods or swamps and are low in biological productivity. The upper Suwannee River 

and the north New River are good examples.

Many major river systems that originate as springs are found in central and north Florida, the 

Big Bend area of the Gulf Coast, and the southern portion of the Tallahassee Hills. Chemically, 

these rivers are clear, alkaline, and well buffered, with little temperature variation. They have 

relatively constant flows and little sediment. Their clear water encourages the growth of 

submerged plants that provide habitat for diverse animal species. Many spring-fed rivers flow 

directly into estuaries; the constant temperatures offer protection from temperature extremes to 

a number of species, including estuarine fish such as spotted seatrout and red drum, as well as

manatees.

Major dams have been built on the Apalachicola, Ocklawaha, Ochlockonee, Hillsborough, and 

Withlacoochee (Citrus County) Rivers. The most extreme alterations were damming the 

Ocklawaha to create the Cross-Florida Barge Canal and channelizing the Kissimmee River. 

The southern third of Florida's peninsula has been so hydrologically altered that few naturally 

flowing streams and rivers remain. Most fresh waterbodies in South Florida are canals, which 

usually support plants and animals more typical of lakes than rivers.

Lakes

Florida's lakes provide important habitats for plant and animal species and are a valuable 

resource for human activities and enjoyment. The state has more than 7,700 lakes, which 

occupy close to 6% of its surface. The largest, Lake Okeechobee (covering 435,840 acres), is 

the ninth largest lake in surface area in the United States and the second largest freshwater 

lake wholly within the conterminous United States.3

 3 Fernald and Purdum, 1998.

 Most of the state’s lakes are shallow, 

averaging 7 to 20 feet deep, although many sinkhole lakes and parts of other lakes can be 

much deeper.
2008 Integrated Water Quality Assessment for Florida

9

Florida’s lakes are physically, chemically, and biologically diverse. Many lakes are spring-fed; 

others are seepage lakes fed by ground water, and still others are depression lakes fed by 

surface water sources. There are two principal lake types, based on color and alkalinity. In 

addition, FDEP has defined 47 different lake regions as part of its Lake Bioassessment/

Regionalization Initiative. These regions provide a framework for assessing lake characteristics 

and establishing management goals and strategies.4

Estuaries and Coastal Waters

 Within each lake region, the lakes have 

similar geology, soils, chemistry, hydrology, and biology, and lakes in one region may differ 

significantly from those in another region. For example, most lakes in the New Hope 

Ridge/Greenhead Slope lake region in northwestern Florida (in Washington, Bay, Calhoun, and 

Jackson Counties) tend to have lower total nitrogen, lower total phosphorus, lower chlorophyll 

concentrations, and higher Secchi depths compared with other Florida lakes. Lakes in the 

Lakeland/Bone Valley Upland lake region in central Florida (in Polk and Hillsborough Counties) 

tend to have higher total nitrogen, higher total phosphorus, higher chlorophyll concentrations,

and lower Secchi depths when similarly compared.

With over 8,000 coastal miles, Florida is second only to Alaska in amount of coastline. The 

state’s west coast alone contains almost 22% of the Gulf Coast estuarine acreage in the United 

States. Florida's estuaries are some of the nation's most diverse and productive. They include 

embayments, low- and high-energy tidal salt marshes, lagoons or sounds behind barrier islands,

mangrove swamps, coral reefs, oyster bars, and tidal segments of large river mouths.

The Atlantic coast of Florida from the mouth of the St. Marys River to Biscayne Bay is a highenergy shoreline bordered by long stretches of barrier islands, behind which lie highly saline 

lagoons. This 350-mile stretch of coast contains only 18 river mouths and inlets. Biscayne Bay 

spans the transition from high- to low-energy shorelines, which are more typical of Florida’s 

west coast.

At the southern end of the state lie Florida Bay and the Ten Thousand Islands, both of which are 

dominated by mangrove islands fronting expansive freshwater marshes on the mainland. Many 

tidal creeks and natural passes connect the islands and marshes. Historically, the area’s fresh 

water came mainly from sheet flow across the Everglades.

Florida's west coast has low relief, and the continental shelf extends seaward for many miles. 

Unlike the east coast, numerous rivers, creeks, and springs contribute to estuarine habitats. 

Generally, the west coast’s estuaries are well-mixed systems with classically broad variations in 

salinity. They often lie behind low-energy barrier islands or at the mouths of rivers that 

discharge into salt marshes or mangrove-fringed bays. The Big Bend coast from the Anclote 

Keys north to Apalachee Bay is low-energy marsh shoreline. While it does not conform to the 

classical definition of an estuary, its flora and fauna are typically estuarine. Many freshwater 

rivers and streams feeding the shoreline here are either spring runs or receive significant 

quantities of spring water. The Florida Panhandle from Apalachee Bay west to Pensacola Bay 

comprises high-energy barrier islands, with sand beaches fronting the Gulf of Mexico.

Major coastal and estuarine habitats vary from northern to southern Florida. Salt marshes 

dominate from Apalachicola Bay to Tampa Bay and from the Indian River Lagoon north to the 

 4 Florida LakeWatch, October 1999a; EPA, 2006a. Additional information on Florida lake regions and the ecology of Florida’s lakes 

is available from Florida LakeWatch (http://lakewatch.ifas.ufl.edu/ and the EPA 

(http://www.epa.gov/wed/pages/ecoregions/fl_eco.htm).
2008 Integrated Water Quality Assessment for Florida

10

Georgia state line. The estuaries west of Apalachicola Bay have few salt marshes. Mangrove 

swamps dominate the southern Florida coast. There are about 6,000 coral reefs between the 

city of Stuart on the Atlantic Coast south and west to the Dry Tortugas, while seagrasses are 

most abundant from Tarpon Springs to Charlotte Harbor, and from Florida Bay to Biscayne Bay.

Wetlands

Because of its low elevation and peninsular nature, Florida has many varied types of wetlands, 

including estuarine Spartina and mangrove marshes, as well as freshwater sawgrass marshes, 

cypress swamps, and floodplain marshes. Wetlands comprise almost one-third of the state. 

The following are the largest and most important in the state:

• The Everglades and the adjacent Big Cypress Swamp. Including the Water 

Conservation Areas (diked portions of the original Everglades system) and 

excluding the developed coastal ridge, this system extends from about 20 miles 

south of Lake Okeechobee to Florida Bay.

• The Green Swamp in the state’s central plateau.

• The Big Bend coast from the St. Marks River to the (South) Withlacoochee 

River.

• Vast expanses of Spartina marsh between the Nassau and St. Mary’s Rivers.

• The system of the St. Johns River marshes. Before alteration by humans, all 

but the northernmost one-fifth of the river basin was an extensive freshwater 

system of swamps, marshes and lakes.5

• The headwaters and floodplains of many rivers throughout the state, especially 

the Apalachicola, Suwannee, St. Johns, Ocklawaha, Kissimmee, and Peace 

Rivers.

 Even today, half of the length of the 

St. Johns River is actually marsh, and in many respects it functions like a 

northern-flowing Everglades. 

Aquifers and Springs

Florida lies atop a vast underground aquifer system that provides potable water to most of the 

state’s population. Ground water naturally discharges into streams, lakes, wetlands, coastal 

waters, and springs. Florida has more than 700 known springs (Figure 1), which discharge 

about 8 billion gallons of water per day (BGD); the state may contain the largest concentration 

of freshwater springs on Earth. The largest spring by discharge is Wakulla Springs, with an 

average discharge of 252 million gallons per day (MGD). Florida also contains 33 of the 78 firstmagnitude springs (defined as springs that discharge on average at least 64.6 MGD) in the 

United States. Several river systems in the state originate as spring discharges.

Archaeological evidence indicates that humans have been attracted to Florida’s life-giving 

springs for thousands of years. Florida’s 14 state parks that are named for springs attract 

millions of visitors each year, and private spring attractions and parks are a multimillion-dollar 

tourist industry.

 5 Kushlan, 1990.
2008 Integrated Water Quality Assessment for Florida

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Figure 1. Springs of Florida

Hydrogeology

Surface Water

Most of Florida is relatively flat. The highest elevations are 345 feet near Lakewood, in Walton 

County in the Panhandle, and 312 feet at Sugarloaf Mountain in the peninsula (Lake County).6

In the past, many wetlands were drained (for agriculture and urban development), and 

numerous rivers were channelized for navigation. The modifications were most intense in south 

Florida where, beginning in the 1920s, canals and levees were built to control flooding and drain 

 

The longest river, the St. Johns on Florida’s east coast, only falls about a tenth of a foot per mile 

from the headwaters to the mouth. Farther south, below Lake Okeechobee, the land relief is 

less than 6 feet. Surface drainage and topographic relief are greatest in the streams and rivers 

entering north and northwest Florida from Alabama and Georgia. Most of these streams are 

alluvial, or sediment carrying. As the land flattens farther south, surface drainage becomes less 

distinct. Rivers and streams are typically slower moving, non-eroding, and non-alluvial.

Many of Florida’s rivers have their headwaters in wetlands. In its natural setting, the Green 

Swamp in central Florida is the headwater for five major river systems: the (South) 

Withlacoochee, Ocklawaha, Peace, Kissimmee, and Hillsborough. In north Florida, the 

Suwannee and St. Marys Rivers originate in the Okefenokee Swamp. Throughout the state, 

smaller streams often disappear into wetlands and later re-emerge as channeled flows.

 6 http://www.americasroof.com/highest/fl.shtml.
2008 Integrated Water Quality Assessment for Florida

12

wetlands. These modifications resulted in the loss of much of the original Everglades wetlands 

from Lake Okeechobee south and the channeling of the Kissimmee River.

Ground Water

Florida is in the Coastal Plain physiographic province, which is blanketed by surficial sands and 

underlain by a thick sequence of bedded limestone and dolomite. Together the surficial sands, 

limestone, and dolomites form an enormous ground water reservoir that provides proportionally 

larger quantities of ground water than in any other state.

These sources of high-quality, potable ground water underlying virtually all of Florida supported 

average withdrawals of more than 5,078 MGD in 2000. This remarkable resource supplies 

more than 90% of the drinking water for more than 18 million residents. In addition, ground 

water resources supply over 50% of all water needs, including agricultural, industrial, mining, 

and electric power generation.

Florida primarily relies on the following four aquifer systems as drinking water sources:

• The Floridan aquifer system, one of the most productive sources of ground 

water in the United States, extends across all of Florida, southern Georgia, and 

adjoining parts of Alabama and South Carolina. Many public water systems—

including Jacksonville, Orlando, Clearwater, St. Petersburg, and Tallahassee—

tap into the Floridan. It is also a major supplier of water for industrial, irrigation, 

and rural use. This aquifer provides 60% (2,790 MGD) of Florida’s potable 

water supplies.

• Unnamed surficial and intermediate aquifers, which are present over much of 

the state, are used when the deeper aquifers contain nonpotable water. They 

supply water needs for about 10% of the population, especially in rural 

locations. These aquifers provide 20% (948 MGD) of the state’s potable water 

supplies.

• In southeast Florida, the Biscayne aquifer supplies virtually all the water needs 

for over 4 million residents in densely populated Dade, Broward, Palm Beach 

and Monroe Counties. This aquifer provides 18% (824 MGD) of Florida’s 

potable water supplies. The EPA has designated the Biscayne Aquifer as a 

sole source drinking water aquifer.

• The sand and gravel aquifer, the major source of water supply in the western 

part of the Florida Panhandle, provides 2% (103 MGD) of Florida’s potable 

water. 

Surface Water–Ground Water Interactions

Florida’s low relief, coupled with its geologic history, has created unique hydrogeologic features. 

Large areas are characterized by karst topography, which forms when ground water dissolves 

limestone. Landforms in these areas include streams that disappear underground, springs and 

seeps where ground water rises to the surface, sinkholes, and caves. Surface water commonly 

drains underground and later reappears, sometimes in a completely different surface water 

basin from where it entered the ground. For example, drainage from a large karst area in 
2008 Integrated Water Quality Assessment for Florida

13

Hydrologic Divide

Source: Fernald and Purdum, 1998

Marion County provides water for Silver Springs, which discharges to the Ocklawaha River and 

then to the St. Johns River and the Atlantic Ocean. The same area also provides water for 

Rainbow Springs, which discharges to the Withlacoochee River and then to the Gulf of Mexico.

Florida's sandy soils, high average rainfall, shallow water table, and porous karst terrain 

promote close and extensive interactions between ground water and surface water. By the 

same mechanisms, surface waters recharge underground aquifers. The fact that Florida 

contains more than one-third of the first-magnitude springs in the United States is an indication 

of significant ground water and surface water interchange. Most lakes and streams receive 

some ground water, but in a 

significant number of watersheds, 

ground water inflow contributes the 

base flow for streams. In the 

Springs Coast region of western 

Florida, for example, ground water 

provides 70% to 80% of the flow in 

spring runs.

A hydrologic divide interrupts the 

movement of Florida’s ground water 

and surface water. The divide is 

represented by an approximate line 

extending from near Cedar Key on 

the Gulf Coast to New Smyrna 

Beach on the Atlantic Coast. Except 

for the St. Johns and Ocklawaha 

Rivers, little, if any, surface water or 

ground water moves across this 

barrier. Most major rivers north of 

the line receive part of their discharges from outside Florida, in addition to rain. South of the 

divide, rain is the sole fresh water source. Hydrologically, the half of Florida lying south of the 

divide is an island. About 75% of the state’s population lives in this area in peninsular Florida.

Water Pollution Control Programs

Florida’s Water Resource Management Program

Florida’s Water Resource Management Program is a comprehensive effort comprising a 

number of activities and programs. These include the Florida Water Plan, watershed 

management, water quality standards, the management of nonpoint source pollution, 

wastewater facilities permitting, ambient monitoring, ground water protection, educational 

programs, and land use management. The Water Resource Management Program also 

includes extensive FDEP coordination with other agencies and programs, including the SWIM 

Program, run by the five regional water management districts.

Florida Water Plan

In 1972, the Florida legislature, recognizing the importance of the state’s water resources, 

passed the Water Resources Act, Chapter 373, F.S., and the Florida Air and Water Pollution 
2008 Integrated Water Quality Assessment for Florida

14

Control Act, Chapter 403, F.S. Many goals and policies in the State Comprehensive Plan, 

Chapter 187, F.S., also address water resources and natural systems protection. Section 

373.036, F.S., outlines the requirements for developing the Florida Water Plan, which is to 

include the following:

• FDEP’s programs and activities related to water supply, water quality, flood 

protection, floodplain management, and natural systems;

• FDEP’s water quality standards for surface water and ground water;

• The water management plans of the water management districts; and

• The Water Resource Implementation Rule (Rule 62-40, Florida Administrative 

Code [F.A.C.]), which provides goals, objectives, and guidance for the 

development and review of programs, rules, and plans relating to water 

resources.

Under Florida's water management system, FDEP oversees the water management districts, an 

approach that balances the need for consistent statewide regulations with regional flexibility. As 

the primary stewards of the state's water resources, FDEP and the water management districts 

often must address competing public demands for water supplies, flood protection, water 

quality, and natural systems protection. To accomplish this, they have developed 

comprehensive water management plans for each region.

Overview of Surface Water Protection Programs

Water Quality Standards Program

Florida’s surface water quality standards system is published in Rule 62-302 (and Section 62-

302.530), F.A.C. The components of this system, which are described below, include water 

quality classifications; water quality criteria; an antidegradation policy; moderating provisions; 

and the special protection of certain waters, such as Outstanding Florida Waters (OFWs), 

because of their natural attributes.

Water Quality Classifications. Florida’s Water Quality Standards Program, the foundation of 

the state’s program of water quality management, designates the “present and future most 

beneficial uses” of the waters of the state (Subsection 403.061[10], F.S.). Florida’s surface 

water is protected for five designated use classifications, as follows:

 Class I Potable water supplies

 Class II Shellfish propagation or harvesting

 Class III Recreation, propagation, and maintenance of a healthy, well-balanced 

population of fish and wildlife

 Class IV Agricultural water supplies (large agricultural lands, located mainly around 

Lake Okeechobee)

 Class V Navigation, utility, and industrial use (there are no state waters currently 

in this class)

Class I waters generally have the most stringent water quality criteria and Class V the least. 

However, Class I, II, and III surface waters share water quality criteria established to protect 

recreation and the propagation and maintenance of a healthy, well-balanced population of fish 
2008 Integrated Water Quality Assessment for Florida

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and wildlife. All waters of the state are considered to be Class III, except for those specifically 

identified in Section 62-302.600, F.A.C. All waters of the state are required to meet the 

“Minimum Criteria for Surface Waters,” as identified in Section 62-302.500, F.A.C.

A Designated Uses and Classification Refinement Policy Advisory Committee (PAC) was 

recently formed to help FDEP re-evaluate the current classifications and assess whether 

refinements or a new system are needed to provide more appropriate levels of protection for 

different surface waterbody types and the uses they support. The PAC met for the first time in 

February 2006. The many complex challenges faced by this committee quickly became 

apparent, and the Department continues to evaluate the options this group has prepared.

Water Quality Criteria. Water quality criteria, expressed as numeric or narrative limits for 

specific parameters, describe the water quality necessary to maintain designated uses (such as 

fishing, swimming, and drinking water) for surface water and ground water. Chapter 3 

discusses the relationship between the state and the EPA’s designated use classifications.

In response to recent initiatives put forth by the EPA, Florida has been working to develop 

biological criteria and nutrient criteria for fresh waters and estuaries.

Antidegradation Policy. The Florida Antidegradation Policy (Sections 62-302.300 and 

62-4.242, F.A.C.) recognizes that pollution that causes or contributes to new violations of water 

quality standards or to the continuation of existing violations is harmful to the waters of the state. 

Under this policy, the permitting of new or previously unpermitted existing discharges is 

prohibited where the discharge is expected to reduce the quality of a receiving water below the 

classification established for it. Any lowering of water quality caused by a new or expanded 

discharge to surface waters must be in the public interest (that is, the benefits of the discharge 

to public health, safety, and welfare must outweigh any adverse impacts on fish and wildlife or 

recreation). Further, the permittee must demonstrate that other disposal alternatives (for 

example, reuse) or pollution prevention are not economically and technologically reasonable 

alternatives to the surface water discharge.

Moderating Provisions. Moderating provisions (provided in Subsection 62-302.300[10] and 

Rules 62-4 and 62-6, F.A.C., and described in Sections 62-302.300, 62-4.244, 62-302.800, 

62-4.243, F.A.C., and Sections 403.201 and 373.414, F.S.) include mixing zones, zones of 

discharge, site-specific alternative criteria, exemptions, and variances. These provisions are 

intended to moderate the applicability of water quality standards where it has been determined 

that, under certain special circumstances, the social, economic, and environmental costs of 

such applicability outweigh the benefits.

Watershed Management Approach

FDEP's statewide approach to water resource management, called the watershed management 

approach, is the framework for developing and implementing TMDLs as required by federal and 

state laws (a later section of this chapter discusses FDEP’s TMDL Program).

Watershed management is a comprehensive approach to managing water resources on the 

basis of hydrologic units—which are natural boundaries such as river basins—rather than 

arbitrary political or regulatory boundaries. It does not focus on individual causes of pollution. 

Instead, each basin is assessed as an entire functioning system, and aquatic resources are 

evaluated from a basinwide perspective that considers the cumulative effects of human 

activities.
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On a simple level, Florida’s watershed management approach provides a mechanism to focus 

resources on specific units (river or estuary basins) rather than trying to work on all state waters 

at one time. An important feature is the involvement of all the stakeholders who have an 

interest in an individual basin (including federal, state, regional, tribal, and local governments 

and individual citizens), in a cooperative effort to define, prioritize, and resolve water quality 

problems. Existing programs are coordinated to manage basin resources without duplicated 

effort.

The watershed management approach is not new, nor does it compete with or replace existing 

programs. Rather than relying on single solutions to water resource issues, it is intended to 

improve the health of surface water and ground water resources by strengthening coordination 

among such activities as monitoring, stormwater management, wastewater treatment, wetland 

restoration, land acquisition, and public involvement.

The Bureau of Watershed Management, within FDEP’s Division of Environmental Assessment 

and Restoration, is responsible for implementing and coordinating watershed management 

activities. The key components of this approach include the following:

• A basin management unit, or geographic or spatial unit, is used to divide the 

state into smaller areas for assessment — generally groups of HUCs. HUCs 

are a nationwide cataloging system commonly used for watershed assessment 

and management. They provide a common framework for delineating 

watersheds and their boundaries at different geographic scales.

• A five-year watershed management cycle provides a set schedule that 

organizes work activities and helps to ensure that all waters are addressed in a 

timely manner. At the conclusion of the cycle, the process begins anew, 

allowing basin managers and stakeholders to respond to changing conditions or 

adjust strategies that have not performed as anticipated. The cycle was 

initiated in the state on July 1, 2000.

• A Basin Management Action Plan (BMAP), developed for each basin in 

cooperation with stakeholders and local communities, coordinates and guides 

management actions. Other plans that provide reasonable assurance that 

water quality goals will be met may also be used. The BMAP specifies how 

pollutant loadings from point and nonpoint sources of pollution will be allocated 

and reduced to meet TMDL requirements.

• Forums and communication networks help participants collect information, 

fill data gaps, and reach a consensus on solutions to the basin’s problems.

• A statewide basin rotation schedule ensures that each of the state’s river 

basins is assessed every five years.

To implement the watershed management approach, Florida’s 52 basins (51 HUCs plus the 

Florida Keys) have been divided into 29 groupings. These have been further subdivided into 5 

groups within each of FDEP’s 6 districts statewide. There are 5 basins each in the Northwest, 

Central, Southwest, South, and Southeast Districts, and 4 basins in the Northeast District. Each 

district assesses 1 basin each year. The order and specific time frame for evaluating each 

basin in each district is based on a number of priority factors, including watersheds that contain 
2008 Integrated Water Quality Assessment for Florida

17

surface water sources of drinking water, watersheds with more severe water quality problems, 

and watersheds where SWIM plans are proposed or under way.

Total Maximum Daily Load Program

Section 303(d) of the federal CWA requires states to submit to the EPA lists of surface waters 

that do not meet applicable water quality standards (i.e., their designated uses or water quality 

criteria) and establish TMDLs for each of these waters on a schedule. Pollution limits are then 

allocated to each pollutant source in an individual river basin. A waterbody that does not meet 

its designated use is defined as impaired.

The 1999 FWRA (Section 403.067, Florida Statutes) clarified FDEP’s statutory authority to 

establish TMDLs, required FDEP to develop a scientifically sound methodology for identifying 

impaired waters, specified that FDEP could develop TMDLs only for waters on a future state list 

of impaired waters developed using this new methodology, and directed FDEP to establish an 

Allocation Technical Advisory Committee (ATAC) to assure the equitable allocation of load 

reductions when implementing TMDLs. The act also declared Lake Okeechobee impaired and, 

as required under the TMDL Consent Decree, allowed the state to develop a TMDL for total 

phosphorus for the lake that was completed in 2001.

Another significant component of the FWRA was the requirement for FDEP and the Florida 

Department of Agriculture and Consumer Services (FDACS) to adopt, by rule, best 

management practices (BMPs) to reduce urban and agricultural nonpoint sources of pollution. 

As Florida already has an urban stormwater regulatory program, this new authority was 

particularly important in strengthening Florida’s agricultural nonpoint source management 

program. This section of the law requires FDACS to adopt, by rule, BMPs to reduce agricultural 

nonpoint source pollution, and for FDEP to verify the effectiveness of the BMPs in reducing 

pollutant loads through monitoring at representative sites. Once FDACS adopts the BMPs, 

landowners must submit a Notice of Intent to FDACS, specifying the BMPs that will be applied 

on specific land parcels and the schedule for BMP implementation. The landowners also must 

maintain records, such as fertilizer use, and allow FDACS staff to inspect the BMPs. By 

submitting a Notice of Intent, the landowners become eligible for state and federal cost-share 

funding to implement BMPs and receive a presumption of compliance that they are meeting 

water quality standards. The BMP rules and the associated BMP manuals that have been 

adopted are available from FDACS’ Office of Agricultural Water Policy at 

http://www.floridaagwaterpolicy.com/.

Florida’s Identification of Impaired Surface Waters Rule (IWR) (Rule 62-303, F.A.C.), provides a 

science-based methodology for evaluating water quality data in order to identify impaired 

waters, and establishes specific criteria for impairment based on chemical parameters, the 

interpretation of narrative nutrient criteria, biological impairment, fish consumption advisories, 

and ecological impairment. The IWR also establishes thresholds for data sufficiency and data 

quality, including the minimum sample size required and the number of exceedances of the 

applicable water quality standard for a given sample size that identify a waterbody as impaired. 

The number of exceedances is based on a statistical approach designed to provide greater 

confidence that the outcome of the water quality assessment is correct. Waters that are 

identified as impaired through the IWR are prioritized for TMDL development and 

implementation.

In 2006, and again in 2007, the IWR was amended to address legal challenges that arose 

following the original adoption in 2001. After the state rulemaking process was completed, the
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revised IWR was submitted to the EPA on September 14, 2007, as a change to water quality 

standards. On February 19, 2008, the EPA sent a letter of approval to FDEP acknowledging 

that the IWR was an approved change to water quality standards.

BMAPs to restore water quality are developed over 18 to 24 months following TMDL 

development. The strategies developed in each BMAP are implemented into National Pollutant 

Discharge Elimination System (NPDES) permits for wastewater facilities and municipal separate 

storm sewer system (MS4) permits.

The 2005 Florida legislature’s amendments to the FWRA focused on the development and 

adoption of BMAPs as an appropriate method for implementing TMDLs. The legislature also 

established a long-term funding source that provides $20 million per year for urban stormwater 

retrofitting projects to reduce pollutant loadings to impaired waters. Additionally, the 2005 

amendments provide FDEP with the ability to take enforcement action against nonpoint sources 

that do not implement the BMPs that they agreed to implement in the BMAP.

Surface Water Improvement and Management Program

In 1987, the Florida legislature passed the SWIM Act, Sections 373.451 through 373.4595, F.S. 

The act directed the state to develop management and restoration plans for preserving or 

restoring priority waterbodies. The legislation designated 6 SWIM waterbodies: Lake Apopka, 

Tampa Bay, Indian River Lagoon, Biscayne Bay, Lower St. Johns River, and Lake Okeechobee. 

As of 2006, SWIM plans had been developed for 47 waterbodies statewide.

The SWIM Program addresses a waterbody’s needs as a system of connected resources, 

rather than isolated wetlands or waterbodies. Its goals are protecting water quality and natural 

systems, creating governmental and other partnerships, and managing watersheds. While 

FDEP oversees the program, the water management districts are responsible for its 

implementation—including developing lists of additional high-priority waterbodies and waterbody 

plans (outlined under Rule 62-43, F.A.C.). The districts also provide matching funds for state 

revenues. In a collaborative effort, other federal and state agencies, local governments, and the 

private sector provide funds or in-kind services.

SWIM plans must contain the following:

• A description of the waterbody;

• A list of governmental agencies with jurisdiction;

• A description of land uses;

• A list of point and nonpoint source discharges;

• Restoration strategies;

• Research or feasibility studies needed to support restoration strategies;

• A restoration schedule;

• An estimate of costs; and

• Plans for interagency coordination and environmental education.
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Pollutant Load Reduction Goals. A pollutant load reduction goal (PLRG) is an estimated 

reduction in stormwater pollutant loadings needed to preserve or restore designated uses in 

SWIM waterbodies that receive stormwater. Ultimately, water quality in a receiving water 

should meet state water quality standards, and PLRGs provide benchmarks toward which 

specific strategies can be directed. Interim PLRGs are best-judgment estimates of the pollution 

reductions from specific corrective actions. Final PLRGs are goals needed to maintain water 

quality standards.

The Water Resource Implementation Rule (Rule 62-40, F.A.C.) requires the water management

districts to establish PLRGs for SWIM priority waters and other waterbodies, and include them 

as part of a SWIM plan, other watershed management plan, or districtwide or basin-specific 

rules.

Point Source Control Program

Florida's well-established wastewater facility permitting program was revised in 1995 when the 

EPA authorized FDEP to administer a partial NPDES Program, and then was expanded again in 

2000 when the EPA authorized FDEP to administer the NPDES stormwater program. While the 

federal program only regulates discharges to surface waters, the state wastewater program 

issues permits for facilities that discharge to either surface water or ground water. Of about 

4,100 wastewater facilities in Florida, approximately 500 are permitted to discharge to state 

surface waters under individual permits. While an additional 500 facilities discharge to surface 

water under general permit authorization (and many others discharge stormwater to surface 

water under the NPDES stormwater program), most wastewater facilities in Florida discharge

indirectly to ground water via land application.

An important component of Florida’s wastewater management is the encouragement and 

promotion of reuse. In fact, the current reuse capacity (year 2004 data) represents about 56%

of the total permitted domestic wastewater treatment capacity in Florida.

FDEP's district offices handle most of the permitting process, with the Tallahassee office 

overseeing the program, providing technical assistance, and coordinating with the EPA. The 

Tallahassee office also oversees the administrative relief mechanisms for applicants that are 

allowed under Florida law, as well as permits for steam electric–generating power plants that 

discharge to waters of the state. Wastewater permits, issued for up to five years, set effluent 

limits and monitoring requirements to provide reasonable assurance that water quality criteria 

will be met. A permit may allow a mixing zone when there is enough dilution to ensure that a 

waterbody's designated use will not be affected. In other special cases, a variance or 

exemption allows certain water quality standards to be exceeded. Facilities that cannot comply 

with new requirements may be issued or reissued a permit containing the effluent limitations to 

be met and an administrative order setting out the steps required to achieve compliance. This 

procedure applies only to facilities complying with an existing permit, and is not used in lieu of 

enforcement when a permittee is out of compliance with an existing permit or operating without 

a required permit.

All facilities must meet, at a minimum, appropriate technology-based effluent limitations. In 

many cases, water quality–based effluent limitations (WQBELs) may also be necessary. Two 

types of WQBELs are used (as defined in Rule 62-650, F.A.C.). Level I WQBELs are generally 

based on more simplified evaluations for streams and for permit renewals. To determine Level 

II WQBELs, which are typically calculated for more complicated situations, a waterbody is 
2008 Integrated Water Quality Assessment for Florida

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generally sampled intensively, and computer models are used to predict its response to a

facility’s discharge.

Ground water discharge permits address an array of discharge options, including sprayfields, 

percolation ponds, and injection wells. Direct discharge to ground water through wells is not 

allowed, except through the Underground Injection Control (UIC) Program. Ground water 

discharges are provided a ”zone of discharge,” where ground water standards are not applied 

and the attenuation and dilution of contaminants occurs in the surficial aquifer. Zones of 

discharge are typically the lesser of 100 feet in diameter or the facility’s property boundary in 

areal extent, and vertically to the top of the next aquifer unit. Ground water monitoring plans are 

required to ensure that ground water flowing from the zone of discharge complies with ground 

water standards. Monitoring plans comprise upgradient background wells and downgradient 

compliance wells, and generally require quarterly monitoring. There are provisions for 

exemptions from individual ground water quality standards that allow certain standards to be 

exceeded. Historically, these have been primarily granted for the sodium standard in coastal 

areas.

Permit Compliance. The primary objective of FDEP’s Wastewater Program is to protect the 

quality of Florida's surface water and ground water by ensuring that permitted wastewater 

facilities meet the conditions of their individual permits and to quickly identify unpermitted 

pollution sources and those facilities that do not meet water quality standards or specific permit 

conditions. To provide proper oversight of the wastewater facilities in the state, FDEP’s

Wastewater Compliance Evaluation Section developed a compliance inspection strategy based 

on its five-year permitting cycle (permits are issued for five years). For NPDES-permitted 

facilities, the goal is to conduct an annual inspect with at least a Compliance Evaluation 

Inspection (CEI) and to conduct a Performance Audit Inspection (PAI) immediately following 

permit renewal. When an NPDES-permitted facility is approximately one year away from 

submitting a permit renewal application, a much more comprehensive inspection, or Fifth Year 

Inspection (FYI), is scheduled. The FYI consists of an overview of the facilities operation, but 

also includes an in-depth sampling plan consisting of a Compliance Sampling Inspection (CSI), 

a Toxic Sampling Inspection (XSI, a Compliance Biomonitoring Inspection (CBI), and an Impact 

Bioassessment (IBI) and Water Quality Inspection (WQI). The results of these inspections help 

to determine if current permit limits are adequate to protect the quality of the receiving waters. 

Land application facilities are also inspected on an annual basis as resources allow; however, 

they are not subject to the same sampling intensity as the surface water dischargers. 

District compliance and enforcement staff make every effort to work with a permittee to resolve 

minor problems before beginning a formal enforcement action. During an inspection, it is the 

inspector’s responsibility to determine if a facility is in compliance with its permit limits and 

compliance schedules. This is accomplished by verifying the accuracy of facility records and 

reports, plant operation and maintenance requirements, effluent quality data (Discharge 

Monitoring Reports, or DMRs), and the general reliability of the facility’s self-monitoring 

program.

Enforcement. FDEP’s Wastewater Program uses the Office of General Council’s Enforcement 

Manual as a guide for developing specific types of enforcement actions such as Consent Orders

and Notices of Violations. However, in order to provide guidance on specific wastewater issues 

related directly to the Wastewater Program, the Wastewater Program Enforcement Response 

Guide was developed to aid inspectors in determining the correct course for corrective actions. 

The guide also provides consistency in addressing enforcement actions specifically related to 

wastewater issues.
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When formal enforcement is necessary, staff attempt to negotiate a consent order—a type of 

administrative order in which civil penalties (such as fines) and corrective actions for 

noncompliance can be assessed. Consent orders also establish step-by-step schedules for 

complying with permit conditions and Florida law.

In 2001, the Florida legislature enacted the Environmental Litigation Reform Act (ELRA) to 

provide a fair, consistent, and expedient method for determining appropriate penalty amounts 

for violations. If a settlement cannot be reached through the consent order process, FDEP has 

the authority to issue a Notice of Violation (NOV) to collect penalties (up to $10,000), as 

specified in ELRA. The NOV can also be used when only corrective actions are needed and no 

penalties are being sought. When a serious violation endangers human health or welfare, or 

the environment, FDEP issues a complaint for injunctive relief or takes other legal action, 

including an immediate final order for corrective action.

Healthy Beaches Program

As part of Florida’s Healthy Beaches Program, FDOH monitors the state’s coastal beaches for 

high levels of bacteria. In August 2000, the beach water sampling program was extended to all 

34 of Florida's coastal counties through state legislation (Senate Bill 1412 and House Bill 2145) 

and funding. With additional funding from the EPA in 2002, the program was expanded to 

include sampling on a weekly basis for fecal coliform and enterococci bacteria at 307 beach 

locations throughout Florida.

In a healthy environment, an array of bacteria is normally found in the soil, on plants, on and in 

ourselves and our pets and other animals, and in water. When concentrations of bacteria are

too high, they can present problems themselves, or they can be an indicator of other organisms 

that can cause problems to humans. Two bacteria types that normally inhabit the intestinal tract 

of humans and animals are fecal coliform and enterococci.

The presence of elevated levels of these enteric bacteria in water is an indication of possible 

pollution that may come from stormwater runoff, pets and wildlife, or human sewage. While not 

necessarily pathogenic, their presence in high concentrations in recreational waters indicates 

that pathogens may be present. If waste pathogens are present in high quantities and are

ingested while swimming, or if they enter the skin through a cut or sore, the bacteria may cause 

human disease, infections, or rashes. The rationale for selecting these two bacteria for analysis 

and the implications of the sampling results are described in more detail on FDOH’s website at

http://esetappsdoh.doh.state.fl.us/irm00beachwater/terms.htm.

If a sampling event leads to a "poor" bacterial indicator result in a single sample, then the county 

health department immediately collects a resample. If the resample confirms the high result, 

then an advisory or warning is issued, signs are posted parallel to the sample point, the results 

are posted on FDOH’s website, and the news media are notified. If the county health 

department cannot collect a timely resample, it issues an advisory or warning with the first 

"poor" result obtained. Sampling events resulting in a "poor" classification normally require 

additional sampling. 

In a calendar year, if FDOH posts more than 21 days of advisories for a waterbody, that

waterbody is considered impaired for swimming, and is listed as impaired on the 303(d) list so 

that the sources of the bacteriological levels can be addressed.
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The most recent results from the current Florida’s Healthy Beaches Program can be reviewed at 

http://esetappsdoh.doh.state.fl.us/irm00beachwater/default.aspx. A sampling history of the 

original counties included in the program and the counties that were added, and a sampling 

history between 1998 and July 2000 are available at 

http://esetappsdoh.doh.state.fl.us/irm00beachwater/history/hisintro.htm.

Nonpoint Source Management Program

The importance of minimizing nonpoint source pollution, especially from new developments, 

was recognized in Florida in the late 1970s when the state’s growth rate increased greatly. 

Over the past 25 years, Florida has implemented one of the most comprehensive and effective 

nonpoint source management programs in the country. The Nonpoint Source Management 

Program includes a mixture of regulatory, nonregulatory, land acquisition, public education, and 

finance assistance components, which are discussed below.

The cornerstone of Florida’s nonpoint source program is the state Stormwater Rule. Florida 

was the first state in the country to establish a statewide Stormwater Permitting Program that 

requires the treatment of stormwater from all new development. The state’s first Stormwater 

Rule was adopted in 1979, with a more comprehensive rule going into effect in February 1982. 

New developments, except for single-family dwellings, and modifications to existing discharges 

must obtain stormwater permits. Projects must include a stormwater management system that 

provides flood control and BMPs such as retention, detention, or wetland filtration to reduce 

stormwater pollutants. The Stormwater Rule, a technology-based rule, establishes design 

criteria for various stormwater treatment BMPs to obtain the minimum level of treatment 

established in the state’s Water Resource Implementation Rule (Rule 62-40, F.A.C.). 

Specifically, these BMPs are designed to remove at least 80% of the total suspended solids 

(TSS) pollutant loading. For OFWs, some other sensitive waters (such as shellfish-harvesting 

areas), and waters that are below standards, BMPs must be designed to remove 95% of the 

TSS loading.

A 1989 stormwater law directed FDEP to establish statewide goals for treatment and to oversee 

the implementation of stormwater regulatory programs, which were also delegated to the water 

management districts. Delegation allows minor design adjustments for Florida’s diverse 

landscape. In 1993, the legislature modified portions of Chapters 373 and 403, F.S., to 

streamline permitting. The Wetlands Resource Permit and the Management and Storage of 

Surface Water (MSSW) Permit were unified into a single Environmental Resource Permit to 

increase statewide consistency in minimizing the impacts of new land uses. 

Therefore, except in the area served by the Northwest Florida Water Management District, 

where FDEP still issues stormwater and dredge-and-fill permits, an Environmental Resource 

Permit is issued that provides for flood control, stormwater treatment, and wetlands protection.

A second important nonpoint source regulatory program is the state’s wetlands protection law 

and permitting program. This program has been instrumental in minimizing the loss of 

wetlands, especially isolated wetlands. Details about this program can be found in Chapter 3, in 

the section on wetlands protection.

As discussed earlier in this chapter (in the section on the TMDL Program), the FWRA requires 

FDACS’ Office of Agricultural Water Policy to develop and adopt, by rule, BMPs to reduce 

agricultural nonpoint source pollution. FDEP is charged with monitoring the effectiveness of the 

BMPs. To date, FDACS has developed and/or adopted BMP manuals for Ridge citrus, Indian 
2008 Integrated Water Quality Assessment for Florida

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River citrus, leatherleaf ferns, silviculture, cow/calf operations, Peace River citrus, vegetable 

and agronomic crops, container-grown plants, forage grass, tri-county agriculture, south Florida 

nurseries, and Gulf citrus. The BMP rules and the associated BMP manuals that have been 

adopted are available at http://www.floridaagwaterpolicy.com/.

This nonregulatory program provides agricultural producers with incentives to implement BMPs. 

Participation in the program opens the door for state and federal cost-share dollars to implement 

BMPs, and it provides the landowner with a presumption of compliance that water quality 

standards are being met. To participate, landowners must submit a Notice of Intent to FDACS, 

specifying the lands to be covered, the BMPs to be implemented, the BMP implementation 

schedule, and the annual tracking requirements such as fertilizer use.

Land acquisition is one of the most important components of Florida’s Nonpoint Source 

Management Program. The state’s first environmental land acquisition program was enacted by 

the legislature in 1972 (the Environmentally Endangered Lands Act). In 1981, the Save our 

Coasts and Save our Rivers Programs were enacted to expand land acquisition. In 1989, 

recognizing the importance of accelerating land acquisition, given the state’s rapid population 

growth, the Preservation 2000 program was enacted. This decade-long program provided $300 

million annually for land acquisition. In 1999, Preservation 2000 was extended for another 

decade by the enactment of the Florida Forever Program, which continued the $300 million 

annual commitment for another decade. These programs have led to the acquisition of over 1 

million acres of sensitive lands.

The state’s growth management program, implemented by the Florida Department of 

Community Affairs (FDCA) and the state’s local governments, is another key component of 

Florida’s Nonpoint Source Management Program. The 1985 State Comprehensive Plan and the 

Local Government Comprehensive Planning and Land Development Regulation Act require 

local governments to establish blueprints for future growth (local comprehensive plans) and to 

adopt local land development regulations to minimize the adverse social, economic, and 

environmental impacts of growth.

Dedicated funding for nonpoint source management programs is crucial to their success. In 

1986, legislation was passed that authorized local governments to implement stormwater utility 

fees to provide funding for stormwater treatment and infrastructure. Today, over 140 of 

Florida’s local governments have implemented a stormwater utility fee, with the average fee for 

a single-family homeowner of $3.50. These dedicated local stormwater funds open the door for 

cost-sharing from FDEP and the water management districts for stormwater retrofitting projects. 

In 1994 the legislature adopted the Nitrate Bill, which imposed a small fee on nitrogen fertilizers. 

These funds are used to fund research to develop BMPs to reduce the leaching of nitrogen into 

ground water, especially from agricultural producers. In 2004, the Nitrate Bill was expanded to 

add a fee for phosphorus fertilizers and to also address the eutrophication of surface waters. In 

1997, legislation expanded the scope of the State Revolving Load Fund to provide funding for 

stormwater retrofitting projects and for agricultural BMP implementation. With the passage of 

the FWRA in 1999, FDEP and FDACS were authorized to receive documentary stamp funding 

for the research and demonstration of urban and agricultural BMPs. Funding has varied from 

$2.8 million to $9.2 million per year. Finally, as discussed earlier, in 2005 the legislature 

established a new funding source that will provide FDEP with about $20 million per year for the 

TMDL Water Quality Restoration Grant Program, allowing FDEP to partner with local 

governments on urban stormwater retrofitting projects.
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Public education on “pointless personal pollution” is the final component of Florida’s Nonpoint 

Source Management Program. Over the past 20 years, a wide variety of educational materials, 

many of which can be customized for local areas, have been developed and distributed. Nearly 

all of these materials are now available electronically and can be downloaded either from 

FDEP’s Nonpoint Source Management Section website

(http://www.dep.state.fl.us/water/nonpoint/), or from the University of Central Florida Stormwater 

Management Academy website (http://www.stormwater.ucf.edu/). Given the state’s rapid 

growth rate, especially from people from out of state, these educational materials are important 

in teaching residents how they contribute to nonpoint source pollution and how they can be part 

of the solution to pointless personal pollution.

Atmospheric Deposition Reduction Strategies

Mercury. Mercury, a naturally occurring toxic trace element, has a complex cycle between the 

Earth’s crust, atmosphere, and oceans. Some mercury is released by natural processes, but 

the predominant emissions to the atmosphere result from human activities, principally the 

mining and smelting of mineral ores, fossil fuel combustion, and the use of mercury itself. 

Today these human activities liberate mercury from its geological sinks into the free 

environment at a rate five to six times higher than in the pre-industrial era. Mercury released in 

this way can travel long distances through atmosphere, ultimately depositing from the air to 

watersheds and wetlands. 

Mercury deposited in wetlands, lakes, and streams can be converted by natural bacteria into 

methylmercury, a toxic form that is accumulated and biomagnified at each link in the food chain. 

In some circumstances, this results in sportfish that would be toxic if eaten by humans and prey 

fish that may be toxic to wildlife that eat them. This effect is particularly acute in the marshes of 

the Florida Everglades, where largemouth bass once contained six times the level of mercury 

safe for human consumption, and wading birds have ingested amounts of mercury close to 

levels that could reduce their populations.

Substantial progress has been made in alleviating the mercury problem in south Florida. 

Human-caused mercury emissions from industrial sources in south Florida, principally 

incinerators, have come under effective control during the past decade; emissions of mercury in 

south Florida have declined by 90%. Subsequently, mercury in fish and wildlife of the 

Everglades has declined by about 75% to date. However, despite these encouraging results, 

mercury levels in fish and wildlife of the region remain excessive. In 2003, the EPA 

promulgated nationwide mercury standards for the nation’s waterbodies; the Florida Everglades 

remains above acceptable limits.

A private–public partnership led by FDEP is investigating ways to alleviate the problem. A 

consortium of electric utility interests and federal and state agencies is collaborating in the 

South Florida Mercury Science Program (SFMSP). SFMSP managers meet regularly to 

apportion research responsibilities, correlate funding requests, and share scientific results on 

Everglades mercury issues. While the SFMSP is focused on the Everglades and south Florida, 

virtually all of its work has statewide and national application.

The EPA and FDEP are developing a field study in south Florida that seeks to obtain robust 

estimates of dry deposition of both fine and coarse particulate matter for mercury (as well as

phosphorus, which is discussed in the next section). The two-year study will commence in 2006 

and conclude in 2008.
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FDEP’s mercury website (http://www.dep.state.fl.us/labs/mercury/index.htm) describes SFMSP 

strategies, plans activities and results. It also provides links to the mercury-related websites of 

SFMSP participants and to other useful websites dealing with mercury.

Beginning in 2007, FDEP initiated an effort to gather the detailed information needed to support 

statewide TMDLs for mercury. Although many of the state’s rivers and lakes have been 

sampled and shown to have mercury in fish tissue concentrations that are well below the 

thresholds that would prompt a consumption advisory, FDEP believes that developing and 

implementing a statewide approach will benefit all Florida’s waters and will be a more costeffective means to set the necessary targets and reductions. Freshwater and marine TMDLs 

are due by September 2012.

FDOH, FDEP, and the Florida Fish and Wildlife Conservation Commission (FWCC) operate 

jointly to determine if environmental chemicals are present in fish from Florida waters. In most 

instances, the FWCC determines what fish species should be sampled and collects those 

samples. FDEP measures the levels of chemicals in fish tissue. FDOH determines the 

potential for adverse human health effects from consuming the fish and issues fish consumption 

advisories when needed. Information on the latest advisories is available on FDOH’s website

(http://www.doh.state.fl.us/environment/community/fishconsumptionadvisories/index.html).

Phosphorus. The fundamental role of phosphorus in controlling primary productivity and 

determining the basic structure of the algal community in freshwater aquatic systems has long 

been recognized. For seepage lakes, which by definition receive the preponderance of their 

hydrologic income from rainfall directly to the lake surface, atmospheric deposition directly to the 

lake is the dominant source of inorganic nutrients. In Florida, the atmospheric deposition of 

phosphorus is particularly important, because approximately 70% of the state’s lakes are 

seepage lakes.

Recent investigations, however, suggest that the atmospheric deposition of phosphorus is of 

secondary importance as a contributor to the load to the Everglades Protection Area. Still, there

has been very little research done to actually measure the dry deposition of phosphorus, or for 

that matter, of nutrients in general. As discussed earlier, the EPA and FDEP are developing a 

field study in south Florida that seeks to obtain robust estimates of dry deposition of both fine 

and coarse particulate matter for phosphorus (as well as mercury, which is discussed in the 

preceding section). The two-year study will commence in 2006 and conclude in 2008.

Nitrogen. The air deposition of nitrates and ammonia (nutrients) can represent a significant 

pollutant load to estuaries and coastal waters (typically nitrogen-limited systems), causing or 

contributing to eutrophication and waterbody impairment. In Florida, Tampa Bay typifies such 

situations, involving a mix of fixed nitrogen loads from point and nonpoint source discharges, 

stormwater, and atmospheric deposition, and posing a challenge for source apportionment and 

abatement through TMDL analyses. There is limited scientific expertise, however, to 

adequately quantify nutrient deposition to the waterbody and watershed.

Current estimates suggest that atmospheric deposition comprises approximately 30% of the 

nitrogen budget of Tampa Bay. This estimate is based, however, on limited ambient monitoring 

data and simple models. In 1999, the EPA, FDEP, and the Tampa Bay Estuary Program 

(TBEP) and its many collaborators initiated a Bay Regional Atmospheric Chemistry Experiment

(BRACE) study to provide better information on air quality in the Tampa Bay area, with specific 

reference to air deposition and its effects on water quality. The results of the study, which will 

be released in the coming year, will provide improved estimates of the effects of local and 
2008 Integrated Water Quality Assessment for Florida

26

regional emissions of oxides of nitrogen (NOx) on the bay and the benefits of implementing

emissions reduction strategies.

Overview of Ground Water Protection Programs

Permitting Programs

FDEP implements a comprehensive ground water quality protection program that establishes 

ground water quality standards, classifications, and permitting criteria. The basis for the 

prevention of ground water contamination is the rule that extablishes Florida’s ground water 

standards, Rule 62-520, F.A.C. Regulatory tools include construction and operation permit 

requirements, setbacks, and ground water monitoring criteria. 

Many additional FDEP rules exist to implement the standards for ground water protection. Each 

rule addresses a specific type of discharge or potential discharge to ground water that, if not 

managed appropriately, may pose a potential threat to the resource. Each rule incorporates 

technical reviews of permit applications and associated data, construction and operation permits 

with standard and specific conditions that ensure all permit requirements are met, ground water 

monitoring, compliance inspections, and enforcement actions when necessary. 

Underground Injection Control

Florida has obtained primacy for implementing the Underground Injection Control Program for 

Class I, III, IV, and V injection wells. The purpose of the program is to protect Florida’s 

underground sources of drinking water (USDWs) from the potentially harmful effects of injection 

wells. A USDW is defined as an aquifer that contains a total dissolved solids concentration of 

less than 10,000 milligrams per liter (mg/L).

There are more than 140 active Class I wells in Florida. The majority of the Class I injection 

facilities in Florida dispose of nonhazardous, secondary-treated effluent from domestic 

wastewater treatment plants, desalinization concentrate, or a blend of these two waste streams. 

Injection wells are required to be constructed, maintained, and operated so that the injected fluid 

remains in the injection zone, and the unapproved interchange of water between aquifers is

prohibited. Class I injection wells are monitored so that if the migration of injection fluids were to 

occur, it would be detected before reaching the USDW. 

There are no Class III wells, and Class IV wells are banned in Florida. Class V wells are 

generally used for the storage or disposal of fluids into or above a USDW. The fluid injected 

must meet appropriate criteria, as determined by the classification of the receiving aquifer. 

Common types of Class V wells in Florida include air conditioning return flow wells, swimming 

pool drainage wells, stormwater drainage wells, lake level control wells, domestic waste wells, 

and aquifer storage and recovery (ASR) wells.

Delineation Program

In 1988, the Florida legislature directed FDEP to implement water well construction and water 

testing standards within areas of known ground water contamination. This was done primarily 

because of a widespread ground water contamination problem with the pesticide ethylene 

dibromide (EDB) in drinking water wells, These actions were taken to protect public health and 

ground water resources, and to promote the cost-effective remediation of contaminated potable 
2008 Integrated Water Quality Assessment for Florida

27

water supplies (Subsection 373.309[1][e], F.S.). While areas have been delineated based on 

detections of solvents and gasoline, EDB, which has been detected in 38 counties statewide, 

has been the primary contaminant serving as the basis for the 427,897 acres delineated under 

Rule 62-524, F.A.C.

FDEP’s primary responsibility in the implementation of Rule 62-524 has been the delineation of 

areas of ground water contamination and the corresponding development of maps identifying 

those areas. These are based on ground water quality data or knowledge of historical land 

uses. Where data are incomplete, a 1,000-foot protective setback is placed around the 

contaminated site or well to estimate the extent of the contaminated plume. The contaminated 

sites and associated plumes are plotted on maps, and each plume is labeled with a unique 

identifier that can be used to determine the contaminants that it contains. A well permitted in a 

delineated area must be tested for the contaminants for which the area was delineated before it 

can be cleared for use.

All delineation maps undergo rigorous internal review, and are adopted under rulemaking 

procedures (Chapter 120, F.S.) that include public meetings and approval by the Environmental 

Regulation Commission. The latest maps produced by FDEP were approved in 1994. 

The implementation of the delineation rule has involved a cooperative effort among FDEP, 

FDOH, and the water management districts. After FDEP delineates areas of ground water 

contamination, the water management districts implement stricter well construction standards 

through permitting requirements. Each permit application for a new well is reviewed to 

determine the well’s location relative to delineated areas. If the well is located in a delineated 

area, the water management district will either require more rigorous well construction 

standards or connection to a public water system. FDOH is responsible for collecting and 

testing water samples.

Wellhead Protection

On August 18, 1998, the EPA approved Florida’s Wellhead Protection Program, which

coordinates and builds on existing programs and rules that protect the state’s ground water 

resources. The program also enables local governments to expand on these rules by 

implementing their own local strategies for protecting drinking water wells. FDEP supports local 

programs by providing technical assistance in wellhead delineation methods and protection 

measures.

The Wellhead Protection Rule, Rule 62-521, F.A.C., establishes a consistent 500-foot radius 

producing a circular wellhead protection area (setback) around all wells that serve community 

and nontransient, noncommunity public water systems. The rule prohibits certain new 

installations from locating in wellhead protection areas and specifies additional performance 

standards for other new installations and activities. Outside of the setback area, the ground 

water protection programs implement specific performance, permitting, and monitoring criteria 

designed to protect ground water on a statewide basis. 

Source Water Assessment and Protection Program

Originally passed by Congress in 1974, the Safe Drinking Water Act (SDWA) was created to 

protect public health by regulating the nation’s public drinking water supply. It establishes 

national standards and practices to prevent the contamination of drinking water sources and to 

ensure proper drinking water treatment and distribution. In 1996, the act was amended to 
2008 Integrated Water Quality Assessment for Florida

28

include the Source Water Assessment and Protection Program (SWAPP). To assess and 

report to the public on potential contaminants of Florida’s source water and threats to public 

water systems, SWAPP comprises the following four key steps: 

• Define the source water protection area,

• Identify known or potential sources of contaminants in the area,

• Determine the susceptibility of the water source to the contaminants, and

• Notify the water systems and the public and explain the significance of the 

contaminants identified in the source inventory.

EPA Region 4 approved Florida’s source water assessment approach on April 1, 2000. The 

Florida assessment, which is geographic information system (GIS) based, is designed to be 

repeated every five years.

In 2004, FDEP assessed all transient noncommunity, nontransient noncommunity, and 

community public water systems. These comprised approximately 6,300 public water systems, 

with close to 12,000 wells and 24 surface water intakes. The results of the assessments were 

sent to the public water systems and posted on the SWAPP website at

www.dep.state.fl.us/swapp. 

Currently, assessments for over 99% of public water systems are posted on the SWAPP 

website. In 62% of the assessed public water systems, no potential sources of contamination 

were found. Of the 38% of systems with one or more potential sources of contamination within 

their assessment areas, the most prevalent potential source is petroleum storage tank facilities, 

followed by wastewater treatment facilities, delineated ground water contamination areas, and 

dry-cleaning sites. 

In 2006, FDEP repeated the SWAPP assessments for approximately 40% of the state. These 

data are currently under review. A complete assessment of all public water systems in the state 

is planned for 2008.

Watershed-based Monitoring and Reporting

Integrating ground water into FDEP’s watershed management approach has required an 

expansion in the approaches for both monitoring design and data analysis to include ground 

water–surface water issues. Historically, the majority of ground water protection efforts 

emphasized land use and aquifer vulnerability, as well as investigating and remediating local 

point sources of contamination to protect potable water supplies. Integrating ground water into 

watershed protection, however, has required the additional consideration of ground water 

contributions to surface waterbodies (i.e., base flow). The water quality of base flow is now also 

considered an equally important ground water use to ensure the support of aquatic life in 

surface waterbodies. Identifying and quantifying ground water contributions where substances 

with extensive natural or anthropogenic abundances in geological deposits coexist with high 

percentages of base flow are also important in evaluating impaired surface waters.

FDEP has developed a methodology and screening tools to evaluate and identify ground water 

resource issues and potential influences of ground water on surface water quality within 

Florida’s watershed management cycle. The findings of these evaluations are used in guiding 

future monitoring and assessment efforts, identifying potential private well sampling needs, and 
2008 Integrated Water Quality Assessment for Florida

29

identifying more detailed evaluations to determine ground water’s influence on impaired or 

potentially impaired surface waters.

Springs Initiative

In 1999, the Secretary of FDEP directed the formation of a multiagency Florida Springs Task 

Force to recommend strategies for protecting and restoring Florida’s springs. In 2000, the task 

force published its findings and recommendations in a report, Florida’s Springs: Strategies for 

Protection and Restoration.

In 2001, the Florida Springs Task Force II was formed to guide the implementation of the “action 

steps” in the report. During the same year, the Florida legislature, with the support of the 

Governor and FDEP’s Secretary, allocated approximately $2.5 million to begin the process of 

protecting and restoring Florida’s springs. Annual funding at that level has continued on an 

annual basis for each succeeding year to the present. As of 2007, approximately $17.5 million 

had been spent in three broad areas: research and monitoring, landowner assistance, and 

educational outreach.

The Florida Springs Initiative has funded a wide variety of projects, including septic system 

upgrades and relocations to reduce nutrient inputs; the development of BMPs for golf courses;

the removal of invasive, non-native aquatic plants; water quality and spring flow monitoring;

ecological studies; dye tracing studies; the development of educational materials; and the 

establishment of Springs Working Groups.

The physical restoration of springs and spring runs has also been a priority, and rules to protect 

state sovereignty springs have been developed and enacted. Educational projects have 

included producing informational booklets and flyers, creating spring-specific local working 

groups, constructing kiosks at highly visited springs, developing and maintaining the awardwinning interactive website, http://www.floridasprings.org, and sponsoring the PBS film, Water’s 

Journey—The Hidden Rivers of Florida. A state-approved educational effort centered around 

the film and associated Web resources is being developed for use in the curricula of Florida 

public schools.

Springs Initiative projects that provide data for 305(b) assessments include the following:

• A quarterly trend-monitoring network, designed to depict long-term trends, that 

includes all of Florida’s clear-water first-magnitude springs (flows of 100 cfs and 

greater) and select second-magnitude springs (flows of 10 to 100 cfs). 

Although this quarterly springs network is not part of the Temporal Variability 

Network discussed in Chapter 3, similar analytes are collected during the same 

months. Quarterly sampling has been ongoing for over six years, and trend 

analyses are in progress. A new effort to prepare annual summaries of springs 

water quality is currently under way.

• Regular biological assessments in spring runs using FDEP’s Stream Condition 

Index (SCI).

• The installation and maintenance of continuous stage and flow gaging stations 

in most first-magnitude spring runs.

• The installation and maintenance of continuous flow metering in selected spring 

caves.
2008 Integrated Water Quality Assessment for Florida

30

• The delineation of ground water basins for major spring systems 

(“springsheds”).

• Biological baseline studies in spring systems.

• Spring-specific ecosystem studies (e.g., Silver Springs 50-Year Retrospective 

Ecosystem Study).

Coordination with Other State, Tribal, and Local Agencies

Florida’s surface water protection programs all emphasize the need for interagency coordination 

in achieving statewide water management goals. Table 2 lists the primary state, local, and 

regional coordination mechanisms for managing water resources. Figure 2 shows the agencies 

responsible for water resource management and coordination in Florida, and lists their principal 

activities.

Table 2. Primary Coordination Mechanisms for Managing State,

Regional, and Local Water Resources

Function/Entity Primary Mechanisms

General supervision over water management 

districts (policies, plans, and programs) 

(Florida Department of Environmental Protection)

a. Water Resources Coordinating Commission

b. Meetings of the water management districts’ executive directors

c. Water Resource Implementation Rule (Rule 62-40, F.A.C.)

d. Florida Water Plan/District Water Management Plan (DWMP) 

work group

e. Issue-specific work groups (policy and rule development)

f. Reuse Coordinating Committee

g. Memoranda of understanding (delegation of programs and 

authorities)

h. Permit streamlining, mitigation banking

i. FDEP review of water management district rules and budgets, 

auditing

Statewide watershed management approach 

(Florida Department of Environmental Protection)

a. Implementation of rotating watershed management cycle for 

assessing the state’s river basins

b. Process for verifying impaired waterbodies in each basin

c. Development of total maximum daily loads (TMDLs) for verified 

impaired waters

d. Adaptive management

State Comprehensive Plan 

(Governor’s Office) Overall coordination by Governor’s Office

State Land Development Plan 

(Florida Department of Community Affairs) Interagency Planning Committees

Florida Transportation Plan 

(Florida Department of Transportation) Interagency plan review process

Strategic regional policy plans 

(Regional Planning Councils)

a. Florida Water Plan/DWMP work group

b. Plan review process (Subsection 186.507[2], F.S., and Rule 

27E-5, F.A.C.)
2008 Integrated Water Quality Assessment for Florida

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Function/Entity Primary Mechanisms

Agricultural interests 

(Florida Department of Agriculture and Consumer 

Services)

Agricultural Water Policy Committee

Local comprehensive plans 

(Florida Department of Community Affairs)

Plan review process

(Rule 9J-5, F.A.C.)

Water supply planning, wastewater management, 

stormwater management, solid waste management

(Local governments)

FDEP and water management district programs for technical and 

financial assistance

Reuse of reclaimed water

(Florida Department of Environmental Protection, 

water management districts, Florida Department of 

Community Affairs, Florida Department of 

Transportation, Public Service Commission)

Reuse Coordinating Committee

U. S. Army Corps of Engineers

a. Public works program

b. State clearinghouse review process

c. Quarterly meetings between FDEP and the Corps

d. Joint FDEP/Corps permit application process (CWA, Section 

404)

e. Memoranda of understanding

f. Potential delegation of Section 404 permitting to FDEP

U. S. Environmental Protection Agency

a. U. S. Environmental Protection Agency (EPA)/FDEP yearly work 

plans and grants

b. EPA technical assistance and special projects

c. Delegation of EPA/CWA programs to FDEP

National Oceanic and Atmospheric Administration a. Grants

b. Cooperative agreements and special projects

U. S. Geological Survey a. Contracts for technical services and data

b. Cooperative agreements

U. S. Department of Agriculture Natural Resource 

Conservation Service (formerly Soil Conservation 

Service)

Contracts for technical services and data

U. S. Forest Service Ecosystem Management teams

U. S. Fish and Wildlife Service

a. Acquisition programs

b. Ecosystem Management teams

c. Special projects

National Park Service a. Acquisition programs

b. Ecosystem Management teams

Alabama and Georgia

a. Memorandum of Agreement for Apalachicola–Chattahoochee–

Flint/Alabama–Coosa–Tallapoosa Rivers Comprehensive Study

b. Suwannee River Coordinating Committee

c. St. Marys River Management Committee

d. Florida–Alabama Water Resources Coordinating Council
2008 Integrated Water Quality Assessment for Florida

32

Federal

Estuary Research,

Weather Forecasting

Clean Water Act

Programs

Research &

Monitoring, Water

Resource Information

Wetlands Permitting,

Flood Control,

Restoration

Land Management

Coordination,

Wildlife Protection

Flood Zone Mapping,

National Flood

Insurance Program &

Disaster Relief

National Oceanic &

Atmospheric Admin .

Environmental Protection

Agency Geological Survey Army Corps of Engineers Fish and Wildlife

Service

Federal Emergency

Management Agency

State

Florida Water Plan, State

Water Policy, Statewide

Pollution Control &

Monitoring,

General Supervision of

Water Management Districts

Growth Management,

Areas of Critical Concern,

Developments of Regional

Impact, Coastal

Management, Fl

Communities Trust

Emergency Management

Coordination, Disaster

Relief

Enforce

Environmental Laws,

Research, Manage &

Assess Impacts to 

Saltwater &

Protect Public Health,

Solid Waste Disposal,

Septic Tanks, Drinking

Water

Water Utility Rate

Structures Approval

for Regulated Utilities

Department of

Environmental Protection Department of Community

Affairs Department of Health Public Service Commission

Regional & Local

Developments of 

Regional Impact,

Growth Management,

Surface Water Quality

Planning & Studies,

Hurricane Evacuation

Planning & Mapping

Regional Planning Councils

Water Resource

Planning, Reg. &

Management, Water

Supply, Flood Protection,

Water Quality Mgt.,

Natural Systems

Protection & Restoration

Water Management Districts

Local Environmental Controls &

Monitoring, Building

Codes/Zoning/Land, 

Provide Potable Water,

Wastewater Services, 

Management/Planning,

Land Acquisition/Management,

Emergency Preparedness

Local Governments

Operation, Maintenance

of Local Surface Water

Management Districts

Chapter 298 District

Special Districts

Water Distribution,

Development of Regional

Sources

Water Supply Authorities

Florida Fish and Wildlife

Conservation Commission

Freshwater Habitats

Figure 2. Agencies Responsible for Water Resource Coordination and Management in Florida

Results of Florida’s Surface Water Protection

Programs

Despite the increase in Florida’s population over the past 35 years, from 6.8 million to almost 18 

million, the state’s surface water management programs have been very successful in 

preventing and minimizing pollution from new sources, especially from new nonpoint sources of 

pollution, and in reducing existing pollutant loadings, especially from point sources of pollution. 

This has been accomplished by implementing new technologies, requiring better treatment of 

wastes, eliminating many surface water discharges, and treating stormwater. Figure 3, which 

shows the history of phosphorus trends in Florida’s surface waters since 1970, illustrates the 

success of the state’s programs. The figure shows that phosphorus pollution began to increase 

beginning in about 1970, peaking in 1982. After 1982, levels decreased because of new 

regulations that eliminated many point sources, encouraged the reuse of treated domestic 

wastewater, and required the treatment of stormwater from all new development.
2008 Integrated Water Quality Assessment for Florida

33

However, the graphic also points to an emerging problem. After trending downward for 20 

years, beginning in 2000 phosphorus levels again began moving upward, perhaps because of 

the cumulative impacts of Florida’s increased population and development.

Two major water quality control programs were responsible for this decreasing trend in 

phosphorus. The first is the state’s point source regulatory/management program, which in the 

early 1980s recognized the low assimilative capacity of many of Florida’s surface waters. This 

led to the implementation of a “no discharge” policy, resulting in the elimination of many point 

sources of pollution and the reuse of treated domestic wastewater. The second program 

responsible for a decline in phosphorus levels in Florida’s waters is the state’s stormwater 

treatment regulatory program. Implemented in 1979, the program was further expanded with an 

increased level of treatment in February 1982, with the implementation of the state’s Stormwater 

Rule.

However, Figure 3 also illustrates an emerging problem. Phosphorus levels have begun to 

increase in recent years, most likely a result of the cumulative effect of nonpoint sources of 

pollution, since the state’s Stormwater Rule is based on a minimum treatment level of 80% 

average annual load reduction. Additionally, Florida’s intensive agriculture industry, together 

with the increasing population and the resulting increase in home landscapes, has led to 

increased fertilizer usage, which undoubtedly is contributing to this upward trend in phosphorus.

Nature and Extent of Nonpoint Source Pollution

Florida’s major water quality concerns are increased nitrates in ground water and increased

nutrients in surface waters. FDEP’s comprehensive Nonpoint Source Management Program, in 

collaboration with the TMDL Program (which is being implemented through the watershed 

management approach), provides the institutional, technical, and financial framework to address 

these issues.

Recommended Nonpoint Source Programs

FDEP is currently evaluating the need to increase the minimum level of treatment of nutrients 

from stormwater discharges and is working with the development community to promote lowimpact development, through approaches such as the Florida Yards and Neighborhoods 

Program, to further reduce nutrient impacts from nonpoint sources of pollution.

Costs and Benefits of Implementing Florida’s Surface Water 

Protection Programs To Meet the Clean Water Act’s Objectives

The EPA, in partnership with the states, conducts the Clean Watersheds Needs Survey 

(CWNS) to identify and document the cost of projects needed to address water quality and 

public health in all 50 states, the District of Columbia, and the U.S.-held territories. The CWNS 

includes detailed estimates of the capital costs eligible for funding under the Clean Water State 

Revolving Fund (CWSRF) Program established by the 1987 Amendments to the CWA—that is, 

CWSRF-eligible costs. The CWNS includes publicly owned municipal wastewater collection 

and treatment facilities; facilities for the control of combined sewer overflows (CSOs); activities 

designed to control stormwater runoff; activities designed to control nonpoint source pollution; 
2008 Integrated Water Quality Assessment for Florida

34

Figure 3. Phosphorus Trends in Florida Waters, 1970–2005

(based on 733,000 measurements from 3,330 waterbodies)

and activities associated with implementing approved Comprehensive Conservation and 

Management Plans (CCMPs) under the National Estuary Program (NEP) established by Section 

320 of the CWA. 

Key elements of the survey are as follows:

• Facilities must be publicly owned and operated,

• Costs represent capital needs (operating and maintenance costs are not 

represented), and

• Costs must be documented.

Historically, the costs have been interpreted as representing 20-year design needs, but more 

recently, since the 1996 survey, costs have been documented by planning and design 

documents representing horizons of 10 years or less.

The survey is conducted every four years, and the results are published in the Clean 

Watersheds Needs Survey Report to Congress. The 2004 survey is available at 

http://www.epa.gov/owm/mtb/cwns/2004rtc/toc.htm. Table 3 provides Florida’s survey results.

Phosphorus pollution peaks 

in early 1980s

0.04

0.05

0.06

0.07

0.08

0.09

0.10

0.11

1970 1975 1980 1985 1990 1995 2000 2005

phosphorus (mg/l)

Phosphorus 

pollution builds 

up in Florida 

waters

In 1982, Florida 

implements Stormwater 

Rule and no-discharge 

policy for point sources

Cumulative effects of 

nonpoint sources are 

driving phosphorus 

levels up again—TMDLs 

are seeking to address 

these impacts
2008 Integrated Water Quality Assessment for Florida

35

These needs are being addressed by several funding mechanisms, most notably the CWA 

State Revolving Fund (SRF) Program; direct congressional appropriations through the State 

and Tribal Assistance Grant (STAG) Program; state appropriations through the Community 

Budget Initiative Request (CBIR) Program; the Comprehensive Everglades Restoration Plan 

(CERP) (a joint 50/50 program funded by Florida and the EPA); Section 319 nonpoint source 

grants; TMDL Water Quality Restoration Grants; and local county, municipal, and water 

management district programs. 

Table 3. Results of the Clean Watersheds Needs Survey for Florida

Category of Need Needs ($000)

Category I – Secondary Treatment $ 33,611

Category II – Advanced Treatment $ 4,595,918

Category III-A – Inflow/Infiltration Correction $ 310,526

Category III-B – Major Sewer Rehabilitation $ 960,088

Category IV-A – New Collector Sewers $ 1,752,257

Category IV-B – New Transmission Facilities $ 1,392,458

Category V – Combined Sewer Overflow Correction 0

Category VI – Municipal Separate Storm Sewer System

 (MS4) Permitted Stormwater Management $ 2,182,750

Category VII – Nonpoint Source BMPs $ 9,285,007

Category VIII – Confined Animals Point Source 0

Category IX – Mining Point Source 0

Category X – Recycled Reclaimed Water Distribution $ 1,672,115

Category XI – Estuary Management $ 63,073

Florida’s Total Needs $22,247,803

Clean Water Act State Revolving Fund Program

The CWA SRF Program provides low-interest loans for water pollution control activities and 

facilities. Water pollution sources are divided into point sources (typically domestic and 

industrial wastewater discharges) and nonpoint sources (generally associated with leaching or 

runoff associated with rainfall events from various land uses). Since the program began in 

1989, FDEP has made over $2 billion in loans. The program revolves in perpetuity, using state 

and federal appropriations, loan repayments, investment earnings, and bond proceeds.

Projects eligible for SRF loans include wastewater management facilities, reclaimed wastewater 

reuse facilities, stormwater management facilities, widely accepted pollution control practices 

(sometimes called BMPs) associated with agricultural stormwater runoff pollution control 

activities, brownfields associated with the contamination of ground water or surface water, and 

estuary protection activities and facilities.

For the SRF Program, the funds awarded/disbursed to date are as follows:
2008 Integrated Water Quality Assessment for Florida

36

Source Awarded Disbursed

Wastewater $2,571,853,033 $1,964,241,331 

Stormwater $116,233,210 $73,599,936 

Nonpoint Sources $16,506,130 $2,960,487 

Construction Grants Program

The primary purpose of federal grant assistance under the Construction Grants Program was to 

help municipalities meet the enforceable requirements of the CWA, particularly applicable 

NPDES permit requirements. Prior to October 1, 1984, EPA grant assistance was limited to a 

maximum of 75% of the allowable costs of building the project and included an allowance for 

facilities planning and design. After September 30, 1984, the federal share was limited to a 

maximum grant of 55% of these costs, unless modified to a lower percentage rate uniform 

throughout the state by the Governor. Innovative and alternative technology projects may have 

received an additional 20% federal share. Before October 1, 1984, eligible projects included

collection systems, intercepting sewers, wastewater treatment facilities, outfall sewers, 

infiltration/inflow (I/I) rehabilitation, and the correction of combined sewer overflows. After 

September 30, 1984, eligible projects included only intercepting sewers, wastewater treatment 

facilities, outfall sewers, and I/I rehabilitation.

For the Construction Grants Program, $1,986,134,673 in funds were disbursed between 1958 

and 1988, after which amendments to the CWA phased out the program and replaced it with the 

SRF Program (discussed above).

Section 319(h) Grant Funds

FDEP’s Nonpoint Source Management Section administers grant money it receives from the 

EPA through Section 319(h) of the federal CWA. These grant funds can be used to implement 

projects or programs that will help to reduce nonpoint sources of pollution. Projects or programs 

are targeted toward the state's nonpoint source priority watersheds, which are the verified 

impaired waters on the 303(d) list, the state's SWIM watersheds, and NEP waters. All projects 

must include at least a 40% nonfederal match. 

Examples of fundable projects include the demonstration and evaluation of BMPs, nonpoint 

pollution reduction in priority watersheds, ground water protection from nonpoint sources, and 

public education programs on nonpoint source management. Section 319 funding from fiscal 

year (FY) 1988 through FY 2007 totaled $102,196,043. Approximately 70% of these funds have 

been used to partner with local governments and water management districts on urban 

stormwater retrofitting projects to reduce stormwater pollutant loadings to priority waterbodies 

such as the Indian River Lagoon and Tampa Bay.

TMDL Water Quality Restoration Grants

With the passage of the 1999 FWRA, FDEP and FDACS also began receiving funds generated 

by documentary stamps to reduce nonpoint source pollution discharged to impaired 

waterbodies. The funding amount has varied from $2.8 to $9.2 million per year with the 

agencies receiving a total of $29 million in the past 6 years. Additionally, Senate Bill (SB) 444,

enacted by the 2005 legislature, created a new funding program that provides $20 million 
2008 Integrated Water Quality Assessment for Florida

37

annually to FDEP, with 7.5% going to FDACS, to be used to reduce pollutant loading from urban 

stormwater discharges or agricultural nonpoint sources. FDEP’s grant funds typically require at 

least a 50% match from grant recipients. 

Special State Concerns and Recommendations

Concerns

Major issues of concern include the following:

• Since the 1970s, scientists have documented increasing levels of nutrients in 

surface water.

• Water quality has declined in most springs since the 1970s; in particular, levels 

of nitrate (a nutrient) have increased.

• The tripling of Florida’s population between 1950 and the present, and the shift 

from natural landscapes to intense urban development, has caused extensive 

habitat loss in aquatic habitats and affected the viability of fisheries in many 

estuarine areas.

• Freshwater harmful algal blooms (HABs) are increasing in frequency, duration,

and magnitude and therefore may be a significant threat to surface drinking 

water resources and recreational areas. Abundant populations of blue-green 

algae, some of them potentially toxigenic, have been found statewide in 

numerous lakes and rivers. In addition, measured concentrations of 

cyanotoxins—a few of them of above the suggested guideline levels—have 

been reported in finished water from some drinking water facilities.

• Based on beach closures and shellfish bed closures, the presence of excessive 

concentrations of bacteria in the water column sometimes limits primary contact 

and recreation use support and shellfish harvesting use support.

• In many coastal and inland waters, excessive concentrations of mercury in the 

tissue of some fish species limit the attainment of designated use.

• Sediments in many urban estuaries such as Tampa Bay, the St. Johns River 

Estuary, and Pensacola Bay contain heavy metals and organic contaminants.

• Recent studies have indicated a declining trend in pH in ocean waters on a 

global scale. Florida has many aquatic species that are sensitive to shifts in 

pH, and site-specific studies in Florida are needed.

Recommendations

To address the special state concerns listed above, FDEP, in cooperation with other agencies 

and stakeholders, has started several initiatives to improve scientific understanding of Florida’s 

water resources and to improve the protection, management, and restoration of surface water 

and ground water. These initiatives include the following:
2008 Integrated Water Quality Assessment for Florida

38

• Statewide DO/Nutrient Monitoring Program. To better understand the 

natural variability of levels of DO and nutrients in the wide variety of freshwater 

aquatic systems around the state, FDEP received a special legislative 

appropriation for a contracted monitoring program. Approximately 350 sites in 

6 different waterbody types were monitored quarterly during 2005–06. 

Monitoring includes the 4-day deployment of YSI data sondes, water chemistry 

samples, and bioassessments. These data will be used to help the state revise 

its DO criterion to reflect the natural variation that occurs (the current criterion is 

5 mg/L for all waters at all times). The data will also be used to develop 

quantitative nutrient criteria to replace the current narrative criterion.

• Nutrient Criteria Development. In the summer of 2001, the EPA published 

waterbody type–specific guidance manuals for lakes and reservoirs, and rivers 

and streams, followed in the fall of 2001 by guidance for estuarine and coastal 

waters. Following a method detailed in these manuals, the EPA undertook 

analyses of the available pools of data to generate Ambient Water Quality 

Criteria Recommendations as summarized below for rivers and streams, and 

lakes and reservoirs for the 3 nutrient ecoregions that Florida partially or wholly 

encompasses. These recommendations are based on an assumption that the 

25th percentile of a distribution of medians for a water quality parameter 

represents a reference condition, and are intended to be revised to more fully 

represent localized conditions while supporting designated uses. Recognizing 

the limitations of EPA’s analysis and recommendations (given that Florida has 

identified up to 47 lake ecoregions), FDEP convened a Nutrient Technical 

Advisory Committee (TAC) to tailor the EPA’s recommended criteria for 

Florida’s aquatic systems. The Nutrient TAC has met 17 times since it was 

established and is making significant progress in addressing the multitude of 

issues associated with establishing scientifically sound quantitative nutrient 

criteria.

• Pollutant Trading Policy Advisory Committee (PAC). The Pollutant Trading 

PAC was established to assist FDEP in developing a pollutant trading program 

and rule in Florida. The PAC members represent different stakeholder groups 

that are involved in the implementation of TMDLs to restore the health of 

impaired waters. A report to the Governor and Florida Legislature on the 

viability of pollutant trading was completed in November 2006 (available:

http://www.dep.state.fl.us/water/tmdl/docs/WQ_CreditTradingReport_final_Dec

ember2006.pdf). FDEP is continuing to pursue rulemaking in this area.

• Statewide Unified Stormwater Rule. The performance standard for the 

minimum level of treatment for new stormwater discharges established in the 

state’s Water Resource Implementation Rule is “80% average annual load 

reduction of the pollutants that cause or contribute to violations of state water 

quality standards.” However, the existing BMP design criteria in the current 

stormwater treatment rules of FDEP and the water management districts were 

based on an 80% average annual load reduction of total suspended solids. In 

October 2007, FDEP Secretary Mike Sole and the Executive Directors of the 

state's five water management districts directed FDEP and district staff to 

develop a conceptual rule based on a performance standard that 

postdevelopment stormwater nutrient loads will not exceed predevelopment 

nutrient loads, where predevelopment land use is the natural land use 

condition. A TAC has been established to provide input to DEP and WMD staff 
2008 Integrated Water Quality Assessment for Florida

39

on the conceptual rule. The rule development process will include the TAC 

meetings (March–October 2008), rule development workshops (November

2008–March 2009), rule adoption (May 2009), and a planned effective date of 

July 1, 2009. Also, the Florida Department of Transportation (FDOT) and 

FDEP, in cooperation with the water management districts, already have 

completely revised the state’s erosion and sediment control BMPs, leading to a 

single statewide manual, which is available at: www.stormwater.ucf.edu.

• Urban Stormwater BMP Research Program. In 2003, FDEP, in cooperation 

with FDOT, partnered with the University of Central Florida to establish the 

Stormwater Management Academy as a center of excellence on urban 

stormwater treatment and management. The academy has completed or is 

conducting research on a variety of urban stormwater BMP issues, including 

the health and water quality risks associated with stormwater reuse, the design 

and effectiveness of green roofs in Florida, the permeability of pervious 

concrete, and the effectiveness of erosion and sediment control BMPs. 

Additionally, FDEP is funding research to determine fertilization and irrigation 

needs to establish and maintain turfgrasses, the impact of wet detention pond 

depth on the effectiveness of stormwater treatment, and the development of 

BMPs to increase nitrogen removal in stormwater. FDEP and FDACS also are 

working with the fertilizer industry to develop Florida-specific formulations of 

slow-release and low-phosphorus fertilizers. This has included the adoption by 

FDACS of the "Urban Turf Rule," which specifies which types of fertilizers can 

be used on urban turf in Florida and in what amounts. The rule is available at: 

https://www.flrules.org/Gateway/View_notice.asp?id=4640400. The 2007 

Florida Legislature also established the Consumer Fertilizer Task Force to 

develop statewide recommendations on the use of fertilizer on urban turf and 

on training and certification requirements for people engaged in the commercial 

application of fertilizer. The Task Force's report is available at: 

http://consensus.fsu.edu/fertilizer-task-force/index.html.

• As part of a much larger statewide initiative to investigate global warming, 

FDEP recently initiated activities to study potential impacts on the state’s

aquatic resources linked to declining pH concentrations in the nation’s coastal 

waters.
2008 Integrated Water Quality Assessment for Florida

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CHAPTER 3: SURFACE WATER 

MONITORING AND ASSESSMENT

Florida’s Surface Water Monitoring Program

Background

FDEP‘s approach to comprehensive surface water monitoring is designed to meet the 

monitoring-related requirements of the federal CWA, as well as Florida’s statutory and 

regulatory monitoring requirements.7

• Determine water quality standards attainment and identify impaired waters,

 Broadly stated, these requirements are as follows:

• Identify the causes and sources of water quality impairments, 

• Establish, review, and revise water quality standards,

• Support the implementation of water management programs,

• Establish special monitoring for unique resources, and

• Support the evaluation of program effectiveness.

FDEP continues to carry out extensive statewide monitoring in order to meet these federal and 

state requirements. However, the state’s surface waters are so abundant that FDEP does not 

have the staff or budgetary resources to monitor every waterbody in the state. Numerous other 

governmental entities at federal, state, regional, and local levels, as well as volunteer and 

private organizations, carry out much of the monitoring. The bulk of the data used in this report 

comes from approximately 79 data providers across the state, who do ambient monitoring of 

water chemistry, collect biological data, and carry out benthic sampling and sampling of 

sediments in estuarine waters. In most cases, these data are initially loaded either into the 

FL(orida) STOrage and RETrieval (STORET) database or FL STORET, and then annually the

data are uploaded to the EPA’s national STORET database. FDEP evaluates, analyzes, and 

reports on these data to establish their utility in determining the health of the state’s ambient 

waters. Some qualifiers are placed on these data, to address issues such as systematic errors. 

 7 At the federal level, Section 305(b) of the 1972 CWA (Federal Water Pollution Control Act, 33 U. S. Code 1251–1375, as 

amended) directs each state to (1) prepare and submit a report every two years that includes a description of water quality of all of 

its navigable surface waters to the EPA, and (2) analyze the extent to which navigable waters provide for the protection and 

propagation of a balanced population of shellfish, fish, and wildlife. Section 303(d) of the CWA requires states to submit to the EPA 

lists of surface waters that are impaired (i.e., that do not meet their designated uses, such as drinking water, recreation, and 

shellfish harvesting, as defined by applicable water quality standards). TMDLs must be developed for each of these impaired 

waters on a schedule. Also, Section 106 (e)(1) of the CWA directs the EPA to determine whether states meet the prerequisites for 

monitoring their aquatic resources.

Monitoring is required under Florida law through a series of rules that govern FDEP’s regulatory activities. The 1997 Water Quality 

Assurance Act (Section 403.063, F.S.) directs FDEP to establish and maintain a ground water quality monitoring network designed 

to detect or predict contamination of the state’s ground water resources. In addition, Section 62-40.540, F.A.C., Florida’s Water 

Policy, states that FDEP “. . . shall coordinate district, state agency, and local government water quality monitoring activities in order 

to improve data quality and reduce costs.”
2008 Integrated Water Quality Assessment for Florida

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For example, by law Florida LakeWatch data can be used only for non-regulatory proceedings 

and cannot be used for enforcement activities. These qualifiers are discussed in greater detail 

later in this chapter.

Each governmental agency and volunteer or private organization has its own monitoring 

objectives, strategy, design, and indicators, as well as procedures for quality assurance, data 

management, data analysis and assessment, and reporting. However, these are beyond the 

scope of this report. Table 4 lists the various entities, including FDEP, that carry out water 

quality monitoring statewide.

Table 4. Federal, State, Regional, and Local Agencies and Organizations

that Carry Out Water Quality Monitoring in Florida

Monitoring Level Monitoring Agency/Organization

Federal

Apalachicola National Estuarine Research Reserve

Avon Park Air Force Range

Charlotte Harbor National Estuarine Program

Eglin Air Force Base

Guana Tolomato Matanzas National Estuarine Research Reserve

National Oceanic and Atmospheric Administration

Rookery Bay National Estuarine Reserve

U. S. Army Corps of Engineers

U. S. Environmental Protection Agency

U. S. Geological Survey

Out of State Georgia Department of Natural Resources

State

Charlotte Harbor Aquatic/Buffer Preserves

Estero Bay Aquatic Preserve

Florida Department of Agriculture and Consumer Services

Florida Department of Health

Florida Marine Research Institute

FDEP’s Ambient Monitoring Program

FDEP’s District offices (6)

FDEP’s Watershed Assessment Section

Florida Fish and Wildlife Conservation Commission

Regional

Choctawhatchee Basin Alliance

Loxahatchee River District

Peace River Manasota Regional Water Authority (PBS&J)

Pensacola Bay Nutrient Study (Gulf Breeze)

Northwest Florida Water Management District

South Florida Water Management District

Southwest Florida Water Management District

Southwest Florida Water Management District (Coast Project)

St. Johns River Water Management District

Suwannee River Water Management District

Local

Alachua County

Bay County

Broward County Environmental Monitoring Division

Charlotte County Storm Water
2008 Integrated Water Quality Assessment for Florida

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Monitoring Level Monitoring Agency/Organization

City of Cape Coral

City of Jacksonville

City of Lakeland

City of Lynn Haven

City of Key West

City of Maitland

City of Naples

City of Orlando

City of Panama City Beach

City of Port St. Joe Project (Gulf Breeze)

City of Port St. Joe Wastewater Treatment Plant

City of Port St. Lucie

City of Punta Gorda Utilities

City of Sanibel

City of Tallahassee

City of Tampa

City of West Palm Beach

Collier County Pollution Control

Dade County Environmental Resource Management

East County Water Control District

Escambia County Utility Association

Hillsborough County

Lake County Water Resource Management

Lee County Environmental Laboratories

Lee County Hyacinth Control District

Manatee County Environmental Management

McGlynn Laboratories and Leon County

Okaloosa County Environmental Council

Orange County Environmental Protection Division

Palm Beach County Environmental Resource Management

Pinellas County Department of Environmental Management

Polk County Natural Resources Division

Reedy Creek Improvement District Environmental Services

Sarasota County Environmental Services

Seminole County Public Works Roads/Stormwater

Seminole Improvement District

St. Johns County

Volusia County Environmental Health Lab

Volunteer/Private

Baskerville Donovan, Inc.

Baywatch

Biological Research Associates

Bream Fisherman's Association

Conservancy of Southwest Florida

Environmental Research and Design, Inc

Florida Center for Community Design + Research

Florida LakeWatch (identification of potentially impaired waters only)
2008 Integrated Water Quality Assessment for Florida

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Monitoring Level Monitoring Agency/Organization

Gulf Power Company

IMCA/Agrico/Phosphates

Janicki Environmental

The Nature Conservancy of the Florida Keys

Palm Coast Community Service Corp.

Sanibel Captiva Conservation Foundation

Southeast Environmental Research Center

Florida’s Integrated Water Resources Monitoring Program

As discussed earlier, water resource monitoring in Florida is conducted by FDEP, the water 

management districts, local governments, and other entities. Over the past decade, FDEP has 

worked very closely with these monitoring entities to establish an Integrated Water Resources 

Monitoring (IRWM) Program that integrates surface water and ground water monitoring, as well 

as water chemistry, biological, and sediment monitoring. Since it is fiscally and logistically 

prohibitive to sample every segment of river or stream, every acre of lake, or each individual 

monitoring well in the state annually, the IWRM also integrates three tiers of monitoring—

statewide probabilistic monitoring that allows statistical inferences to be made about all waters 

in the state; more intensive basin monitoring; and site-specific monitoring (Table 5). These 

three tiers are composed of eight core monitoring programs in FDEP’s Division of Water 

Resource Management.

The IWRM approach is consistent with the EPA’s 2003 guidance document, Elements of a State 

Water Monitoring and Assessment Program,8

1. Monitoring objectives, 

and addresses the following 10 elements:

2. Monitoring strategy, 

3. Monitoring design, 

4. Indicators, 

5. Quality assurance, 

6. Data management, 

7. Data analysis and assessment, 

8. Reporting, 

9. Programmatic evaluation, and 

10. General support and infrastructure planning.

This section broadly discusses Elements 1 (monitoring objectives), 2 (monitoring strategy), 5 

(quality assurance), 6 (data management), 9 (programmatic evaluation), and 10 (general 

support and infrastructure planning). The methodology and assessment sections of this chapter 

address Elements 3 (monitoring design), 4, (indicators), 7 (data analysis and assessment), and 

8 (reporting).

 8 U. S. Environmental Protection Agency, March 2003.
2008 Integrated Water Quality Assessment for Florida

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Table 5. Summary of FDEP’s Monitoring Programs (Tiers I, II, and III)

Tier Program Summary Resources Addressed

Tier I

Status Network

Consists of a probabilistic monitoring design 

to estimate water quality across the entire 

state based on a representative subsample of 

water resource types.

Large Lakes

Small Lakes

Large Rivers

Small Streams

Confined Aquifers

Unconfined Aquifers

Temporal 

Variability 

Network

Comprises a fixed station design to examine 

changes in water quality and flow over time 

throughout the state.

Large Rivers

Small Streams

Confined Aquifers

Unconfined Aquifers

Tier I

Tier II

blend

Tier II

Springs 

Initiative

Consists of a fixed station network of 

freshwater springs intended to enhance the 

understanding of Florida’s springs, stop the 

degradation and loss of spring flow, and 

restore springs to their former health.

First-magnitude springs

Second-magnitude 

springs

Subaquatic conduits

River rises

Coastal submarine 

springs

Strategic 

Monitoring 

Program

Addresses questions in specific basins and 

stream segments that are associated with 

determinations of waterbody impairment for 

the TMDL Program.

All surface waters based 

on the schedule in the 

watershed management 

cycle

Tier III

Intensive 

Surveys for 

TMDLs

Provides detailed, time-limited investigations 

of the conditions of specific surface water 

resources that are identified as impaired.

Specific surface water 

resources identified as 

impaired

Water Quality 

Standards 

Development

Develops, evaluates, and revises new and 

existing surface water quality standards. 

Carries out monitoring to determine 

concentrations to protect aquatic life and 

human health.

Surface water

Ground water

Site-Specific 

Alternative 

Criteria

Develops moderating provisions unique to a 

waterbody that does not meet particular 

water quality criteria, due to natural 

background conditions or human-induced 

conditions that cannot be controlled or 

abated.

Surface waterbodies to 

which particular ambient 

water quality criteria may 

not be applicable

Fifth-Year 

Inspections

Achieves and maintains compliance through 

sound environmental monitoring and 

permitting practices.

Surface waters that 

receive point source 

discharges
2008 Integrated Water Quality Assessment for Florida

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Element 1: Monitoring Objectives

The goal of FDEP’s monitoring activities is to determine the overall quality of the state’s surface 

water and ground water, how they are changing over time, and the effectiveness of water 

resource management, protection, and restoration programs. Monitoring activities collectively 

address the following broad objectives:

• Identify and document the condition of Florida’s water resources with a known 

certainty;

• Determine the proportion of the state’s waterbodies that meet water quality 

thresholds and other indicators of ecosystem health;

• Identify water quality changes over time in the state, in individual river basins, 

and in specific waterbodies;

• Collect data on important chemical, physical, and biological parameters to 

characterize waterbodies that do not meet the applicable Florida water quality 

standards and criteria in the IWR (Rules 62-302 and 62-303, F.A.C.);

• Conduct monitoring that is consistent with the criteria set forth in the IWR;

• Identify waters that are currently on the 303(d) list as verified impaired, or 

identify waters that are no longer determined to be impaired;

• Collect data for waters that are suspected to be impaired that were originally 

not on the 303(d) list; 

• Collect data on waterbodies that currently have few or no data for assessing 

their impaired status;

• Continue to collect data that will be useful in assessing changes over time in 

the status of impaired waters;

• Establish a scientific database that can be useful in determining the status of a 

basin’s long-term overall health;

• Provide reliable data to help refine management decision making;

• Establish a water database with known data quality objectives and quality 

assurance that can be used to help establish water quality standards; 

• Help provide data to evaluate the effectiveness of clean water projects and 

programs; and

• Provide technically sound information to managers, legislators, agencies, and 

the public.

Element 2: Monitoring Strategy

Under FDEP’s IWRM approach, there are three tiers of monitoring, ranging from the general to 

the specific, designed to fill data gaps or support specific regulatory needs. Each of FDEP’s

eight core monitoring programs has a detailed monitoring design, a list of core and 

supplemental water quality indicators, and specific procedures for quality assurance, data 

management, data analysis and assessment, reporting, and programmatic evaluation. FDEP 
2008 Integrated Water Quality Assessment for Florida

46

relies on both chemical and biological sampling in all of its monitoring programs, and also 

conducts the bulk of the biological sampling that is carried out statewide. Table 5 briefly 

describes FDEP’s approach and the water resources addressed for each FDEP monitoring 

program.

Based on the goals and objectives of each individual core monitoring program, sample locations 

are selected, monitoring parameters and sampling frequencies are determined, and sample 

collection and analysis are coordinated among FDEP’s districts; cooperating federal, state, and 

county agencies; and volunteer monitoring groups. This close coordination with other 

monitoring entities around the state is essential to prevent duplication and to maximize the 

number of waterbodies that are monitored on a regular basis.

FDEP’s three tiers of monitoring are as follows:

• Tier I consists of FDEP’s statewide surface water and ground water Status and Trend 

(Temporal Variability, or TV) Networks. The Status Network uses a rotating-basin, 

probabilistic monitoring design to estimate water quality across the entire state, based 

on a representative subsample of water resource types. The TV Network uses a fixed 

station design to examine changes in water quality and flow over time throughout the 

state. The objective of these networks is to provide scientifically defensible information 

on the important chemical, physical, and biological characteristics of surface waters and 

major aquifer systems of Florida. Both networks are designed to measure condition 

using a variety of threshold values, including water quality standards, water quality 

indices, and other appropriate ecological indicators.

• Tier II includes the Strategic Monitoring Program, which is designed to address 

questions in specific basins and stream segments that are associated with 

determinations of waterbody impairment for the TMDL Program. Monitoring in 

response to citizen concerns and environmental emergencies is also considered Tier II. 

In addition, this tier includes the Springs Initiative, which encompasses all of the 

extensive monitoring activities begun in 1999 to address the needs of Florida’s 

freshwater spring systems. This fragile and unique resource type is considered to be at 

risk.

• Tier III addresses questions that are regulatory in nature. Examples of Tier III 

monitoring activities include monitoring to determine whether moderating provisions 

such as site-specific alternative criteria (SSACs) should apply to certain waters, all 

monitoring tied to regulatory permits issued by FDEP, monitoring to establish TMDLs 

(intensive surveys), and monitoring associated with evaluating the effectiveness of best 

management practices (BMPs). On a much more infrequent basis, when state water 

quality standards are under evaluation for revision or new development, Tier III also 

includes monitoring activities associated with these efforts.

Element 5: Quality Assurance

Because water quality monitoring is carried out by many agencies and groups statewide, FDEP 

has a centralized quality assurance (QA) program to ensure that data are properly and 

consistently collected. A Quality Assurance Officer coordinates and oversees data quality 

activities for each program. However, QA is the responsibility of everyone associated with 

sampling, monitoring, and data analysis.

Training classes, which are conducted by FDEP staff, focus on program-specific sampling 

requirements. Any updates or changes to an individual program’s monitoring protocols are 
2008 Integrated Water Quality Assessment for Florida

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communicated through project management meetings, statewide meetings, an Internet website, 

and training classes.

The accuracy of field measurements is assessed through internal FDEP programs. Staff also 

monitor the on-site sampling environment, sampling equipment decontamination, sample 

container cleaning, the suitability of sample preservatives and analyte-free water, and sample 

transport and storage conditions.

For each monitoring program, field staff are instructed to follow a comprehensive set of 

Standard Operating Procedures (SOPs) set forth in Rule 62-160, F.A.C., and specified in the 

FDEP document, Standard Operating Procedures for Field Activities (DEP-SOP-001/01,

February 1, 2004). 

Water quality samples are sent to FDEP’s Central Laboratory for analysis for the majority of 

programs, and to a lesser degree to district laboratories for limited analyses, such as 

bacteriological tests and turbidity. FDEP labs have SOPs for handling and analyzing samples, 

reporting precision, accuracy and method detection limits that apply, and reporting data. 

Laboratory certification is maintained as required by Section 62-160.300, F.A.C. The Quality 

Assurance Rule (Rule 62-160, F.A.C.), which was adopted on June 8, 2004, requires all entities 

submitting data to FDEP be certified by the National Environmental Laboratory Accreditation 

Conference (NELAC) through FDOH.

Element 6: Data Management

The smooth and timely flow of water quality data from sample collectors and analytical agencies 

to data analysts is a high priority. FDEP’s Watershed Monitoring and Watershed Data Services 

Sections comprise the lead IWRM organization. Assisted by cooperating federal, state, and 

county agencies, sample locations are selected, monitoring parameters and frequencies 

determined, and sample collection and analysis coordinated. This information is communicated 

electronically to the sampling agencies before sampling commences.

Some data collected in the field are computerized at the sampling agency, using a customized 

FDEP computer program that facilitates the flow of data from the field. Water quality samples 

are tracked from the field to the lab. Files containing analytical data are transferred to FDEP, 

processed and merged with corresponding field data, and linked to the corresponding site data. 

Computerized accuracy and completeness checks are run, in addition to a variety of other QA 

checks. FDEP staff manually check each data file to identify any obvious random or systematic 

errors. 

All data collected are uploaded to STORET annually. Periodically, data are uploaded to FDEP’s

Oracle-based Generalized Water Information System (OGWIS), which is available to FDEP

staff. All data collected are uploaded to STORET annually.

Element 9: Program Evaluation

Florida, in consultation with the EPA, reviews each monitoring program to determine how well 

the program serves its water quality decision needs for all state waters. EPA and FDEP QA 

audits are used in evaluating each program to determine how well each of the EPA’s 

recommended elements is addressed and how to incorporate needed changes and additions 

into future monitoring cycles.
2008 Integrated Water Quality Assessment for Florida

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Element 10: General Support and Infrastructure Planning 

The EPA’s general support and infrastructure planning element is encompassed by a number of 

activities. FDEP’s Central Laboratory provides laboratory support for all eight core monitoring 

programs. The Watershed Monitoring and Data Management (WMDM) Section provides both 

administrative and technical support primarily to three of the eight programs: the Status 

Network, Temporal Variability Network, and the TMDL Program.

Evolving Approaches to Monitoring

Florida continues to develop new approaches to monitoring. FDEP has developed a number of 

biological indices to characterize the condition of surface waters and has adopted these indices 

for use in water resource assessments at all three tiers of monitoring. The following new 

indicators that FDEP is currently using integrate the biological responses from land uses in a 

basin and can provide a measure of resource health:

• FDEP uses a macroinvertebrate-based index, BioReconnaissance (BioRecon), 

as a rapid assessment tool. The BioRecon is a 6-metric index ranging from 0 to 

10. If a site scores less than 6 on the index, it is recommended for a further, 

more intensive study using the SCI method.

• A composite macroinvertebrate index for use in flowing streams, the SCI is 

used as a definitive measure of impairment. Data generated on the species 

composition and abundance of organisms in a stream are used to calculate 10

biological metrics. Points are assigned for each metric, based on regionally 

calibrated criteria.

• Similarly, the Lake Condition Index (LCI), which uses six metrics, is used to 

characterize noncolored lakes statewide. However, LCIs will not be included in 

rules and will not be used for bioassessment as an LCI score, but will be used 

as a collection method.

• Florida has also launched a lake condition characterization, the Lake 

Vegetation Index (LVI), employing plant community (macrophyte) composition. 

Using transects and a visual survey, the results can be compiled for a rapid 

assessment of lake condition.

• A Wetland Condition Index, using vegetation, macroinvertebrates, and algae, 

has been developed for some freshwater wetland systems (depression 

marshes and forested wetlands only). This tool is being used to refine FDEP’s 

rapid wetland assessment methodology for permitting/mitigation and to assess 

the effectiveness of wetland restoration projects.

• Florida has also developed geochemical- and biology-based tools to measure 

the quality of sediments in marine and freshwater systems. Sediments will be 

collected from a statistical sampling of lake resources in the state as part of the 

Status Network. The resulting data will then be compared with a geochemical 

tool developed to measure naturally occurring concentrations of metals, and 

biology-based thresholds will be used to estimate levels of potentially toxic 

contaminants in sediments. 
2008 Integrated Water Quality Assessment for Florida

49

Surface Water Assessment

Statewide Probabilistic Assessment (Tier 1)

Update 2006–08

From 2004–08, the Status Network design used the TMDL rotating basins (Figure 4) and 

sampled five to six TMDL basins each year. The design supports annual analysis and reporting 

on each individual basin unit. Sampling the rotating basins using the Status Network’s 

probabilistic design has continued through the present (see Appendix C for the methodology 

used for the probabilistic design). The collection of water resource samples from the entire 

state will be completed at the end of 2008, and a statewide summary will be prepared at the 

completion of the five-year cycle. The 2010 version of the Integrated Report will contain this full 

report on surface and ground waters in the state. 

Data from the Status Network are summarized and reported for each basin unit and are 

available on the FDEP website at http://www.dep.state.fl.us/water/monitoring/basins.htm. 

Reports are readily accessible for the Group 1 basins, and others will be added as they become 

available. 

Figure 4. Five-Year Rotating Basin Cycle in FDEP’s Six Districts
2008 Integrated Water Quality Assessment for Florida

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Starting in 2009, the Tier 1 monitoring for the Status Network will change. There will be a new 

emphasis on producing an annual report on statewide condition, and FDEP will move away from 

the TMDL basin design, which allows a statewide estimate after 5 years of data collection. As in 

the previous cycle of sampling, four surface water resources (rivers, streams, large lakes, and 

small lakes) will be used, as well as two ground water resources (confined and unconfined 

aquifers). Instead of 30 samples per TMDL basin (29 basins) per resource, 120 results for each 

of the 4 surface water and 2 ground water resources will be used to represent statewide 

condition. Overall, fewer samples will be collected to make the annual statewide estimate. 

Surface water samples will be collected two times per year per site. Questions have been 

raised about variance in surface water quality in response to seasonality and changes in 

condition due to rainfall/drought events. This will be evaluated by collecting waters in opposite 

seasons statewide. The results from these two events will be evaluated to determine if the 

response in comparison to thresholds is significant enough to warrant the duplicate sample. 

A long-term benefit to the annual approach for both surface and ground waters is the ability to 

examine trends in water quality over time. The annual approach coupled with the existing trend 

monitoring network will provide a more comprehensive picture of changes to water quality. This 

will consist of the two components: annual (probabilistic) and monthly (Trend Network).

Analytes

The candidate lists of indicators measured as part of the IWRM Status Network were derived 

from multiple discussions with the participating agencies and consist of core and supplemental 

indicators used to evaluate water quality. It is cost-prohibitive to fully analyze all water 

resources for every potential contaminant, including emerging contaminants. Therefore, 

specific analytes were selected for monitoring surface and ground water resources for Tier I. 

These were carefully chosen to capture the most common water quality and biological 

measures of condition.

Physical/chemical/biological indicators (Tables 6 and 7) were selected in the past for the status 

and trend monitoring networks, and are discussed in greater detail in Appendix B. These have 

been reviewed for adequacy for the next monitoring initiative and comprise the predominant list 

of analytes that will be incorporated in future monitoring initiatives. Discussion is under way to 

include additional biological measurements as new biocriteria are developed. Indicator lists for 

surface water resources are designed to detect the major threats to surface water quality, such 

as eutrophication and habitat loss. 

The interpretation of data is based on standards or thresholds to determine if the water meets 

the appropriate designated use (i.e., recreational, aquatic life use, potable). When reporting 

results, these thresholds for the selected indicator are used to make statements of water quality. 

Not all analytes of interest have standards or guidance values; those reported in this document 

are those that do. Investigation of more specific water conditions can be conducted in Tier II 

and III assessments to characterize individual waterbodies, or areas where contamination might 

be suspected.

Sample results are used to estimate the conditions of the grouping of a resource (lakes, for 

example). The percentage of lakes meeting or not meeting the threshold is reported for the 

entire group of basins, based on the statistical estimate of 30 samples, with a known error. The 

Tier I efforts are not designed for the individual analysis of any resource but can be used to help 
2008 Integrated Water Quality Assessment for Florida

51

determine what constituents of concern might be present in the basin for that particular water 

resource. 

For ground water resources, Florida’s chief source of drinking water, key indicator contaminants 

(e.g., chloride, nitrate, and bacteria) serve to assess the general suitability of this resource for 

drinking water purposes. In Cycle 1 of the Status Network, aquifer samples were filtered to 

mitigate well construction factors, and the analytes were measured as dissolved constituents. 

This was changed in Cycle 2 to total constituents, in order to reflect more closely the actual 

conditions for drinking water and to be consistent with standards. 

Table 8 lists the surface and ground water quality criteria used for the analysis of data collected 

in the status and trend monitoring networks. 

Monitoring Program Strategy for All Tiers of Monitoring 

The monitoring program strategy was submitted to and approved by the EPA for all tiers of the 

IWRM Program. The document describing the strategy is available at 

http://www.dep.state.fl.us/water/monitoring/docs/MonitoringStrategy_106.pdf. Its format follows 

the guidance provided in the EPA document, Elements of a State Water Monitoring and 

Assessment Program (March 2003);9

Trend Monitoring 

the components of these elements are discussed for all 

tiers of FDEP monitoring. 

Surface and ground water trend monitoring will continue, and reports on these trends will be 

available on FDEP’s Watershed Monitoring website at 

http://www.dep.state.fl.us/water/monitoring/ as they are completed.

 9 Available: http://www.epa.gov/owow/monitoring/elements/.
2008 Integrated Water Quality Assessment for Florida

52

Table 6. Indicators Used for the Status and Trend Monitoring Networks

T = Total sample; X = Other sample or measurement

Indicator Lakes 

(large)

Lakes 

(small) Streams Rivers Aquifers

Calcium T

Magnesium T

Sodium T

Chloride T

Sulfate T

Fluoride T

Alkalinity T

Nitrate + Nitrite T T T T T

Ammonia T T T T T

Kjeldahl Nitrogen T T T T T

Total Phosphate T T T T T

Aluminum, Arsenic, Cadmium, Chromium, 

Copper, Iron, Lead, Manganese, Zinc T

Dissolved Solids T

Sediments:

Organics and Metals X X

Turbidity T T T T T

Color T T T T T

Fecal Coliform T T T T T

Total Coliform T

Enterococci T T T T

Chlorophyll a T T T T

Algal Growth Potential* X

Phytoplankton X X

Water Temperature X X X X X

pH X X X X X

Specific Conductance/Salinity X X X X X

Dissolved Oxygen X X X X X

Turbidity X

Secchi Depth X X X X

Total Depth X X X X

Sample Depth X X X X

Depth to Water (from Land Surface 

Elevation [LSE]) X

LSE X

Micro-landuse X

Floristic Quality Index X

Biological Community 

(Stream Condition Index [SCI]) X X

Habitat Assessment and Flow X X
2008 Integrated Water Quality Assessment for Florida

53

Table 7. Temporal Variability Network Core and Supplemental Indicators

Indicator Surface Water Ground Water

Calcium T D

Magnesium T D

Sodium T D

Potassium T D

Chloride T D

Sulfate T D

Fluoride T D

Alkalinity T D

Nitrate + Nitrite T D

Ammonia T D

Total Kjeldahl Nitrogen T D

Aluminum, Arsenic, Cadmium, Chromium, 

Copper, Iron, Lead, Manganese, Zinc* T

Phosphorus T D

Specific Conductance D D

Orthophosphate D D

Total Organic Carbon T T

Total Dissolved Solids T T

Total Suspended Solids T T

Turbidity T T

Color T T

Total Coliform T

Fecal Coliform T T

Enterococci T

Chlorophyll a T

Water Temperature X X

pH X X

Specific Conductance/Salinity X X

Dissolved Oxygen X X

Turbidity X

Secchi Depth X

Total Depth X

Sample Depth X

Depth to Water (from LSE) X

Land Surface Elevation (LSE) X

Biological Community 

(Stream Condition Index [SCI])* X

Habitat Assessment and Flow* X

T = Total sample; D = Filtered sample; X = Other sample or measurement

* = Collected once a year per site beginning in October 2004.
2008 Integrated Water Quality Assessment for Florida

54

Table 8. Water Quality Standards

Analyte Criterion Use

Chloride

Fluorides

Total Dissolved Solids

250 mg/L

1.5 mg/L

1,000 mg/L (maximum)

Potable Water Supply

Fecal Coliform Bacteria 400 (single-sample maximum) Recreation

Alkalinity

Dissolved Oxygen

Fluorides

pH

Specific Conductance

Turbidity

Unionized Ammonia

(Calculated from temperature, 

pH, salinity, ammonia)

20 mg/L

> 5 mg/L

10 mg/L

>6, <8.5 su

1,275 or 50% above background

29 NTUs above background

0.02 mg/L

Aquatic Life

su – Standard unit; NTUs – Nephelometric turbidity units

Statewide Basin Assessment (Tier II)

Approach to the Comprehensive Assessment: Sections 305(b) and 303(d)

The EPA has requested that the states merge their reporting requirements under the CWA for 

Section 305(b) surface water quality reports and Section 303(d) lists of impaired waters into an 

Integrated Water Quality Monitoring and Assessment Report (Wayland, 2001). As part of its 

TMDL assessment, FDEP prepares Water Quality Status Reports and Assessment Reports that 

integrate the 303(d) list and the 305(b) report for each of the state’s 29 river basins. These 

reports are available at http://www.dep.state.fl.us/water/basin411/default.htm. (At the bottom of 

the screen, select the basin group that you want to access [Groups 1–5], click on the name of 

an individual river basin on the map, and when that basin map appears, click above it to access 

the Status and Assessment Reports.)

Following the EPA’s guidance, FDEP delineated waterbodies or waterbody segments in each 

basin, assessed them for impairment based on individual parameters, and then placed them 

into one of five major assessment categories and subcategories. These categories provide 

information on a waterbody’s status based on water quality, sufficiency of data, and the need for 

TMDL development (Table 9). The EPA allows states to develop individual subcategories to fit 

a unique or specialized set of circumstances. These subcategories must be consistent with the 

purpose of the more general category and be approved by the EPA during its review of each 

state’s methodology for developing lists of impaired waters. In addition, as part of making 

known to the public its assessment procedures, the state should describe the categories and 

subcategories it applies. In Florida, these procedures are clearly presented during the 

development of each year’s set of impaired waters lists. New subcategories developed since 

the submittal of the 2006 impaired waters lists includes Subcategories 4d and 4e, which were 

described at a series of eight public meetings held around the state in support of the Group 5 

lists and at six other public meetings for the Group 1 lists, respectively.
2008 Integrated Water Quality Assessment for Florida

55

Table 9. Categories for Waterbodies or Waterbody Segments in the 2008 Integrated Report

Category Description Comments

1 Attaining all designated uses

If use attainment is verified for a waterbody or segment that 

was previously listed as impaired, FDEP will propose that it 

be delisted.

2

Attaining some designated uses and 

insufficient or no information or data are 

present to determine if remaining uses are 

attained

If attainment is verified for some designated uses of a 

waterbody or segment, FDEP will propose partial delisting for 

the uses attained. Future monitoring will be recommended 

to determine if remaining uses are attained.

3a No data and information are present to 

determine if any designated use is attained

Future monitoring will be recommended to determine if 

designated uses are attained.

3b

Some data and information are present but 

not enough to determine if any designated 

use is attained

Future monitoring will be recommended to gather sufficient 

information and data to determine if designated uses are 

attained.

3c

Enough data and information are present to 

determine that one or more designated uses

may not be attained according to the 

Planning List methodology

A waterbody or segment is potentially impaired for one or 

more designated uses. These waters will be prioritized for 

future monitoring to verify use attainment or impaired status.

3d

Enough data and information are present to 

determine that one or more designated uses 

are not attained according to the Verified List 

methodology

A waterbody or segment exceeds Verified List evaluation 

criteria and may be listed as impaired at the end of Phase 2 

of the watershed management cycle. However, the data 

have not yet been fully evaluated and the waters have not 

been formally verified as impaired. Further monitoring and 

analysis may be necessary.

NOTE: This category is applicable only to the Status Report. 

Waters presented in Phase 1 of the watershed management 

cycle that appear to meet the Verified List criteria.

4a

Impaired for one or more designated uses 

but does not require TMDL development 

because a TMDL has already been 

completed

After the EPA approves a TMDL for the impaired waterbody 

or segment, it will be included in a Basin Management Action 

Plan to reduce pollutant loading toward attainment of 

designated use(s).

4b

Impaired for one or more designated uses 

but does not require TMDL development 

because the water will attain water quality 

standards due to existing or proposed 

measures

Pollutant control mechanisms designed to attain applicable 

water quality standards within a reasonable time frame are 

either proposed or in place.

4c

Impaired for one or more criteria or 

designated uses but does not require TMDL 

development because impairment is not 

caused by a pollutant

This category includes waterbodies or segments that are 

impaired because of naturally occurring conditions or 

pollution. This typically applies to impairments tied to low 

dissolved oxygen (DO) or elevated iron concentrations. The 

impairment is not caused by specific pollutants, but is 

believed to be natural or caused by pollution.1

4d No causative pollutant has been identified

The waterbody does not meet its applicable criteria, but no 

causative pollutant has been identified. This typically applies 

to low DO or failed biological assessments. All available 

biological data, total nitrogen (TN), total phosphorus (TP), 

and biological oxygen demand (BOD) data, and land use 

have been assessed. . Waterbody impairments identified in 

this category will be submitted to EPA for inclusion on the 

303(d) list.

4e

Impaired, but recently completed or ongoing 

restoration activities are underway to restore 

the designated uses of the waterbody

Restoration activities for this waterbody are underway to 

restore the waterbody. All requirements for placing the 

waterbody into category 4b have not been finalized or 

approved by the Department. Because the Department 

recognizes the implementation of restoration activities with 

the goal of restoring water quality, a TMDL will not be 

scheduled at this time. Waterbody impairments identified in 

this category will be submitted to EPA for inclusion on the 

303(d) list. 

5 One or more designated uses is not attained Waterbodies or segments in this category are impaired for 
2008 Integrated Water Quality Assessment for Florida

56

and a TMDL is required one or more designated uses by a pollutant or pollutants. 

Waters in this category are included on the basin-specific 

Verified List adopted by FDEP’s Secretary as Florida’s 

impaired waters list and submitted to the EPA as Florida’s 

303(d) list of impaired waters at the end of Phase 2.

Note: The descriptions in Table 9 are consistent with the EPA’s integrated assessment categories. In the Water Quality Status 

Reports for Groups 1 through 3 and in the Water Quality Assessment Reports for Groups 1 through 2 that were previously 

produced, Categories 4b and 4c were reversed. That is, the description of Category 4b was previously listed as Category 4c, and 

the description of Category 4c was listed as Category 4b.

1 For purposes of the TMDL Program, pollutants are chemical and biological constituents, introduced by humans into a waterbody, 

that may result in pollution (water quality impairment). There are other causes of pollution, such as the physical alteration of a 

waterbody (for example, canals, dams, and ditches). However, TMDLs are established only for impairments caused by pollutants (a 

TMDL quantifies how much of a given pollutant a waterbody can receive and still meet its designated uses).

Waterbodies that are verified impaired due to specified pollutants are listed under Category 5 in the Integrated Assessment Report; 

waterbodies with water quality impairments due to other causes, are listed under Category 4c. Although TMDLs are not established 

for Category 4c waterbodies, these waterbodies still may be addressed through a watershed management program (for example, 

the Kissimmee River restoration).

_________________________________

The primary purpose of the assessments for the TMDL Program is to determine if waterbodies 

or waterbody segments are to be placed on the Verified List of impaired waterbodies. The 

listings are made in accordance with evaluation thresholds and data sufficiency and data quality 

requirements in the IWR (Rule 62-303, F.A.C.). The results of the assessment are used to 

identify waters in each basin for which TMDLs will be developed.

Determining impairment in individual waterbodies for the TMDL Program takes place in two 

phases. First, in each river basin FDEP evaluates the existing water quality data, using the 

methodology prescribed in the IWR, to determine whether waters are potentially impaired. 

Waters found to be potentially impaired are included on a Planning List for further assessment 

under Subsections 403.067(2) and (3), F.S. As required by Subsection 403.067(2), F.S., the 

Planning List is not used to administer or implement any regulatory program; it is submitted to 

the EPA for informational purposes only.

The second step is to assess waters on the Planning List under Subsection 403.067(3), F.S., as 

part of FDEP’s watershed management approach (described earlier). FDEP carries out 

additional data gathering and strategic monitoring, focusing on these potentially impaired 

waters, and determines—using the methodology in the IWR—if a waterbody is, in fact, impaired 

and if the impairment is caused by pollutant discharges.

A Water Quality Assessment Report is produced containing the results of this updated 

evaluation and a Verified List of impaired waters. (Group 5 reports are included on a CD.) The 

criteria for the Verified List are more stringent than those for the Planning List. FDEP is required 

to develop TMDLs for waters on the Verified List under Subsection 403.067(4), F.S. A 

watershed management plan (called a Basin Management Action Plan, or BMAP) to reduce the 

amount of pollutants that cause impairments may also be produced and implemented.

The Verified List is adopted by Secretarial Order in accordance with the FWRA. Once adopted, 

the list is submitted to the EPA for approval as the state’s Section 303(d) list of impaired waters 

for the basin.
2008 Integrated Water Quality Assessment for Florida

57

To implement the watershed cycle, the state’s river basins have been divided into five groups 

within each of FDEP’s six districts statewide, and each district will assess one basin each year. 

Table 10 shows the basin groups for implementing the cycle in FDEP’s districts. Table 11,

which lists the basin rotation schedule for TMDL development and implementation, shows that it 

will take nine years to complete one full cycle of the state. Over time, the 1998 303(d) listing, as 

well as the listings for preceding cycles (Cycle 1, Cycle 2, etc.), are all taken into account in the 

subsequent cycle. This results in a conservative approach to keeping problem waters on the 

list.

The watershed management cycle is an iterative, or repeated, process. One of its key

components is that the effectiveness of management activities (TMDL implementation) will be 

monitored in successive cycles. Monitoring conducted in Phase 2 of subsequent cycles will be 

targeted at evaluating whether water quality objectives are being met and whether individual 

waters are no longer impaired. FDEP also will track the implementation of scheduled 

restoration activities, whether required or voluntary, to ensure continued progress towards 

meeting the TMDLs.

Table 10. Basin Groups for Implementing the Watershed Management Cycle,

by FDEP District Office

District Group 1

Basins

Group 2

Basins

Group 3

Basins

Group 4

Basins

Group 5

Basins

Northwest Ochlockonee–

St. Marks Rivers

Apalachicola–

Chipola Rivers

Choctawhatchee 

River and Bay–

St. Andrew Bay

Pensacola Bay Perdido River and 

Bay

Northeast Suwannee River Lower St. Johns 

River – St. Marys–Nassau Rivers

Northeast Coast 

Lagoons

Central Ocklawaha River Middle St. Johns 

River

Upper St. Johns 

River Kissimmee River Indian River Lagoon

Southwest Tampa Bay Tampa Bay 

Tributaries

Sarasota Bay–

Peace and Myakka 

Rivers

Withlacoochee 

River Springs Coast

South Everglades West

Coast Charlotte Harbor Caloosahatchee River Fisheating Creek Florida Keys

Southeast Lake Okeechobee

St. Lucie–

Loxahatchee 

Rivers

Lake Worth 

Lagoon–

Palm Beach Coast

Biscayne Bay–

Southeast Coast Everglades

Table 11. Basin Rotation Schedule for TMDL Development and Implementation 

Year 00 01 01 02 02 03 03 04 04 05 05 06 06 07 07 08 08 09 09 10

Group 1 PHASE 

1

PHASE 

2

PHASE 

3

PHASE 

4

PHASE 

5

PHASE 

1

PHASE 

2

PHASE 

3

PHASE 

4

PHASE 

5

Group 2 PHASE 

1

PHASE 

2

PHASE 

3

PHASE 

4

PHASE 

5

PHASE 

1

PHASE 

2

PHASE 

3

PHASE 

4

Group 3 PHASE 

1

PHASE 

2

PHASE 

3

PHASE 

4

PHASE 

5

PHASE 

1

PHASE 

2

PHASE 

3

Group 4 PHASE 

1

PHASE 

2

PHASE 

3

PHASE 

4

PHASE 

5

PHASE 

1

PHASE 

2

Group 5 PHASE 

1

PHASE 

2

PHASE 

3

PHASE 

4

PHASE 

5

PHASE 

1

1st Five-Year Cycle – High-Priority Waters 2nd Five-Year Cycle – Medium-Priority Waters

Note: Projected years for Phases 3, 4, and 5 may change due to accelerated local activities, length of plan development, legal 

challenges, etc.
2008 Integrated Water Quality Assessment for Florida

58

Determining Attainment of Designated Use(s)

The designated uses of a given waterbody are established using the surface water quality 

classification system described in the section on Florida’s Water Quality Standards Program in 

Chapter 1. Specific water quality criteria, expressed as numeric or narrative limits for specific 

parameters, describe the water quality necessary to maintain each of these uses for surface 

water and ground water.

It is important to note, however, that the EPA uses slightly different terminology in its description 

of designated uses. Because FDEP is required to provide use attainment status for both the 

state’s 305(b) report and the state’s 303(d) list of impaired waters, FDEP uses EPA terminology 

when assessing waters for use attainment. The water quality evaluations and decision 

processes for listing impaired waters that are defined in Florida’s IWR are based on the 

following designated use attainment categories:

Aquatic Life Use Support-Based Attainment

Primary Contact and Recreation Attainment

Fish and Shellfish Consumption Attainment

Drinking Water Use Attainment

Protection of Human Health

Table 12 summarizes the designated uses assigned to Florida’s various surface water 

classifications.

Table 12. Designated Use Attainment Categories for Surface Waters in Florida

Designated Use Attainment Category Used in 

IWR Evaluation Applicable Florida Surface Water Classification

Aquatic Life Use Support-Based Attainment Class I, II, and III

Primary Contact and Recreation Attainment Class I, II, and III

Fish and Shellfish Consumption Attainment Class II

Drinking Water Use Attainment Class I

Protection of Human Health Class I, II, and III

How Data Are Identified and Evaluated

The Impaired Surface Waters Rule. To identify impaired waters in each of the state’s river 

basins, FDEP evaluates water quality data using the science-based methodology in the IWR 

(Rule 62-303, F.A.C.), which went into effect in 2002. The rule establishes specific criteria and 

thresholds for impairment, in addition to data sufficiency and data quality requirements. The 

methodology described in the rule is based on a statistical approach (called the binomial 

method) designed to provide greater confidence that the outcome of the water quality 

assessment is correct. 

As part of the watershed management approach, for each river basin in the state FDEP follows

the methodology in Section 62-303.300, F.A.C., to develop a Planning List of potentially 

impaired waters to be assessed under Subsections 403.067(2) and (3), F.S. The methodology 

for developing the Planning List includes an evaluation of aquatic life use support, primary 

contact and recreational use support, fish and shellfish consumption use support, drinking water 

use support, and protection of human health. Only in limited circumstances can data older than 
2008 Integrated Water Quality Assessment for Florida

59

10 years be used to evaluate water quality criteria exceedances for the Planning List.10

Revisions to the Impaired Surface Waters Rule. In 2006, and again in 2007, the IWR was 

amended to address legal challenges that arose following its original adoption in 2001. After the 

state rulemaking process was completed, the revised IWR was submitted to the EPA on 

September 14, 2007, as a change to Florida Water Quality Standards. On February 19, 2008,

the EPA sent a letter of approval to FDEP acknowledging that the IWR was an approved 

change to the Water Quality Standards. The revisions are available at 

 As 

required by Subsection 403.067(2), F.S., the Planning List will not be used to administer or 

implement any regulatory program, and is submitted to the EPA for informational purposes only.

After further assessment, using the methodology in Part III, Section 62-303.400, F.A.C., FDEP 

determines if waters on the Planning List are, in fact, impaired and if the impairment is caused 

by pollutant discharges. These waters are placed on a Verified List. The criteria for the Verified 

List are more stringent than those for the Planning List. Other than those instances identified in 

the IWR, data older than 7.5 years are generally not used to verify impairment.10

 The Verified 

List is adopted by Secretarial Order and forwarded to the EPA for approval as part of the 

Section 303(d) list of impaired waters for the State of Florida. FDEP develops TMDLs for these 

waters under Subsection 403.067(4), F.S. FDEP also submits the impairments contained in 

categories 4d and 4e to EPA for approval as part of the 303(d) list for the State of Florida. 

However, TMDLs are not scheduled for these waters at this time.

http://www.dep.state.fl.us/water/tmdl/docs/RevisionsIWR.pdf. The substantive changes to the 

IWR include the following:

• Scope and Intent (Section 62-303.100)—Portions of the IWR are changes to standards, but 

their use is limited to ambient assessments done under Sections 303(d) and 305(b) of the federal 

Clean Water Act. This change does not apply to permitting or other agency actions.

• Total Coliform—Total coliform will no longer be listed as a parameter causing impairment.

• Whole Effluent Toxicity (Sections 62-303.340 and .440)—The section on toxicity was deleted, 

and a short reference was added to toxicity test results under biological assessment.

• Daily Average Marine DO Criterion (Subsection 62-303.320[5])—The use of the binomial 

method will be allowed to evaluate daily average marine DO. To calculate the daily average, at 

least 4 samples must be collected within a day, at least 4 hours apart.

• Evaluation of Water Quality Data for Exceedances (Sections 62-303.320 and .420)—FDEP 

will continue to use the binomial method for assessing exceedances of conventional pollutants 

and metals. However, for synthetic pesticides and organic compounds the EPA-recommended 

method will be used (i.e., waters will be listed if there is more than 1 exceedance in 3 years).

• Age of Data (Subsections 62-303.320[3] and .400[3])—Older data can be used if they are 

representative of current conditions. FDEP must demonstrate why the data are representative 

and document this finding in the administrative record.

• Sample Representativeness (Subsection 62-303.320[4])—The requirement for data from at 

least 3 different seasons/quarters (not necessarily within the same year) has been removed. 

However, there must be at least 5 temporally independent sampling events.

 10 To evaluate water quality exceedances, the EPA requests that FDEP use older data, when available. If a decision can be made 

using available, recent data, then FDEP uses those data. However, when a decision cannot be made, then FDEP uses older data if 

it is available. Considerations include whether the data come from FDEP’s own lab, what quality assurance procedures were used 

in collecting the data, and whether metadata are available.
2008 Integrated Water Quality Assessment for Florida

60

• Quality Assurance Evaluation (Subsection 62-303.320[8])—To track Rule 62-160, F.A.C., 

metadata will be requested if FDEP suspects quality assurance problems, or if it is considering 

listing a water as impaired based on a small sample size.

• Assessment of Chlorophyll a and TSI Data (Section 62-303.350)—The annual average will be 

calculated as the average of each season/quarter, and then average seasons. For new data, TN, 

TP, and chlorophyll a must be collected at the same time and location to calculate the TSI. The 

use of data from four consecutive seasons is permitted, if no years in the assessment period 

have sufficient data. There is a new requirement for “corrected” chlorophyll a (for new data only).

• Fecal Coliform Criteria (Rule 62-302)—FDEP is currently still negotiating these rule changes 

with the EPA. Potential revisions include using the binomial method and assessing each fecal 

coliform sample independently even if samples are taken within 4 days of each other, changing 

the listing threshold to 1 exceedance for the monthly average and requiring 10 samples per 

month for Class III waters, and directing FDEP to assess whether samples are representative of 

in-situ conditions.

• Use of Shellfish Harvesting Classification Information (Subsections 62-303.370[3] and 

.470[5])—A water will be listed as impaired if the harvesting classification is downgraded from the 

initial classification (or if coliform data indicate impairment). Class II waters will be listed if they 

are not approved for shellfish harvesting, except for (1) conditionally approved waters where 

wildlife is the only source as identified by FDEP’s Shellfish Environmental Assessment Section 

(SEAS) and (2) prohibited waters established for administrative, precautionary reasons.

• Minimum Sample Size (Subsection 62-303.420[7])—The minimum will be waived if there are 5 

exceedances and fewer than 20 samples, or if there is “other scientifically credible and 

compelling information... that provides overwhelming evidence of impairment.” The rationale 

must be documented in the administrative record. This change is similar to previous clauses that 

allow listing for “other information” indicating impairment.

Public Participation Process. FDEP works with a variety of stakeholders in the TMDL 

process. It also solicits and encourages public participation in a number of ways. It maintains 

an extensive distribution list; hosts a TMDL Program website (available at 

http://www.dep.state.fl.us/water/tmdl/index.htm); publishes notices of meetings, workshops, and 

public hearings in the Florida Administrative Weekly, on the website, and in local newspapers;

makes available to the public (via the website, mail, or e-mail) the basin-specific draft Verified 

Lists of waters that meet the requirements of the IWR; holds public meetings on developing and 

adopting the Verified Lists of impaired waters for the state’s 29 river basins; and requests and 

responds to public comments.

Citizens are given the opportunity to comment on the draft lists in person and/or in writing. As 

part of the review process, public workshops are advertised and held in each basin to help 

explain the process for developing the Verified List, exchange information, and encourage 

public involvement. If additional information or data is provided prior to or during the public 

comment period, FDEP considers it before submitting the proposed list to the Secretary and 

EPA.

Sources of Data. FDEP’s assessment of water quality for each basin statewide includes an 

analysis of quantitative data from a variety of sources, many of which are readily available to the 

public. These sources include the EPA’s Legacy and modernized STORET databases, the 

U.S. Geological Survey (USGS), FDEP, FDoH, the water management districts, local 

governments, and volunteer monitoring groups.
2008 Integrated Water Quality Assessment for Florida

61

Historically, FDEP carried out statewide water quality assessments using data available in the 

EPA’s Legacy STORET Database; Legacy STORET makes up approximately 40% of the 

statewide data used in the IWR assessment. The Legacy STORET dataset is a repository of 

data collected and uploaded by numerous organizations through 1999. The Legacy STORET 

Database can be accessed at http://www.dep.state.fl.us/water/storet/index.htm.

In 2000, the EPA created a modernized version of STORET that included new features 

designed to address data quality assurance/quality control concerns (the new STORET website

is available at http://www.epa.gov/storet/. However, because of software difficulties associated 

with batch uploading of data to modernized STORET, FDEP has decided to rebuild a local 

version of STORET with much easier data-loading capabilities (referred to as the Water 

Integrated Database [WID] project). Modernized STORET currently houses only about 30% of 

the statewide IWR Database.

Approximately 30% of the data used in the IWR assessment is provided by individual 

organizations that for various reasons, such as time constraints or resource limitations, are not 

able to enter their data into the national database. The organizations providing the largest 

datasets include the South Florida, Southwest Florida, and St. Johns River Water Management 

Districts; the USGS; and the University of Florida LakeWatch volunteer monitoring group. 

Several of these databases are readily available to the public via the Internet: the South Florida 

Water Management District at http://www.envirobase.usgs.gov/, the USGS at 

http://water.usgs.gov/, and LakeWatch at http://lakewatch.ifas.ufl.edu/.

An added source of information is available from the Florida Fish and Wildlife Research Institute 

(http://research.myfwc.com/), which provides weekly updates on the occurrence of Harmful 

Algal Blooms (HABs). While some HABs may adversely affect humans and wildlife, not all 

species produce toxins that cause illness or death in humans or marine organisms. (A more 

detailed discussion of HABs begins on page 80 of this report.) While outbreaks of HABs have 

been suspected or documented in Florida’s waters since 1844, not all outbreaks are severe or 

extensive, nor is there a clear correlation between outbreaks and the influence of human 

activities. However, many of Florida’s fresh water waterbodies affected by HABs have been 

identified as impaired through our IWR metrics measuring Chlorophyll a or through FDEP’s 

evaluation of information related to imbalance of flora and fauna. Examples include Lake 

Okeechobee, the St. Johns River, and Lake Munson.

The FWRI staff have indicated that red tide (Karenia brevis) outbreaks are an offshore 

phenomenon, but may migrate toward shore. However, K. brevis is a marine species and does 

not survive in lower salinity (<20 ppt) environments, such as nearshore or estuarine waters.

Based on these factors, the FWRI staff maintain that the effects of added nutrient loads coming 

from man’s activities on the land and delivered to estuaries and coastal waters are not 

responsible for initiating the offshore blooms or exacerbating blooms in Florida’s waters.

Preliminary studies by FWRI scientists indicate that the major nutrient source for K. brevis is 

from species mortality, linked with a red tide event. Therefore, based on current information, 

waters will not be placed on Florida’s list of impaired waters based on the outbreak of red tide.

In summary, when it is determined that a specific, reoccurring HAB adversely affects the 

designated use of a particular waterbody and is caused by pollutant, that waterbody will be 

added to FDEP’s verified list of impaired waters. 
2008 Integrated Water Quality Assessment for Florida

62

FDEP created the IWR Database in 2002 to evaluate data simultaneously in accordance with 

the IWR methodology for every basin in the state, based on the appropriate data “window.” 

Tables 13a and 13b show the periods of record for the Verified and Planning Lists for the five 

basin groups for the first and second basin rotation cycles.

Table 13a. Data Used in Developing the Planning and Verified Lists,

First Basin Rotation Cycle

Basin Group Reporting Period of Data Record Used in IWR 

Evaluation

Group 1 Planning List January 1, 1989 – December 31, 1998

Verified List January 1, 1995 – June 30, 2002

Group 2 Planning List January 1, 1991 – December 31, 2000

Verified List January 1, 1996 – June 30, 2003

Group 3 Planning List January 1, 1992 – December 31, 2001

Verified List January 1, 1997 – June 30, 2004

Group 4 Planning List January 1, 1993 – December 31, 2002

Verified List January 1, 1998 – June 30, 2005

Group 5 Planning List January 1, 1994 – December 31, 2003

Verified List January 1, 1999 – June 30, 2006

Note: Typically, a 10-year data record is used for the development of the Planning Lists, and a 7.5-year record is 

used for the Verified Lists.
2008 Integrated Water Quality Assessment for Florida

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Table 13b. Data Used in Developing the Planning and Verified Lists,

Second Basin Rotation Cycle

Basin Group Reporting Period of Data Record Used in IWR 

Evaluation

Group 1 Planning List January 1, 1995 – December 31, 2004

Verified List January 1, 2000 – June 30, 2007

Group 2 Planning List January 1, 1996 – December 31, 2005

Verified List January 1, 2001 – June 30, 2008

Group 3 Planning List January 1, 1997 – December 31, 2006

Verified List January 1, 2002 – June 30, 2009

Group 4 Planning List January 1, 1998 – December 31, 2007

Verified List January 1, 2003 – June 30, 2010

Group 5 Planning List January 1, 1999 – December 31, 2008

Verified List January 1, 2004 – June 30, 2011

Note: Typically, a 10-year data record is used for the development of the Planning Lists, and a 7.5-year record is 

used for the Verified Lists.

Quality Assurance/Quality Control Criteria. The IWR addresses quality assurance/quality 

control (QA/QC) concerns by requiring all data to meet QA rule requirements (Rule 62-160, 

F.A.C.), including NELAC certification and the use of established SOPs. Starting one year after 

the effective date of the rule, on June 8, 2004, the IWR also requires that data providers make 

available upon request a list of QA/QC metadata11

Rationales for Not Using Existing Data. FDEP uses all water quality data that are provided 

through STORET, as long as it is ambient in nature (e.g., it does not use data for water coming 

out of a discharge pipe or within approved mixing zones). It may restrict the use of an agency’s

data if consistent errors have been found (only the water quality parameters that have problems

are restricted). FDEP also may restrict an agency’s data if it has failed QA/QC inspections. 

elements with their data. The metadata 

requirements are designed to allow FDEP to conduct a number of electronic checks on the 

quality of data.

Criteria for Evaluating Outside Data. Occasionally, in closely evaluating data for a particular 

waterbody, FDEP may find systematic errors from a data provider. These errors may include 

the blatant shifting of decimals for a parameter such as iron (e.g., reporting 1,000 mg/L, rather 

than 1 mg/L). When systematic errors are found, those data are censored from the analysis, 

and FDEP works with the provider to correct the errors. Upon correction, the data are used in 

the assessment.

The Florida legislature has specifically prohibited the use of data from the volunteer monitoring 

group LakeWatch in any regulatory proceeding. However, LakeWatch data can be used in

developing the Planning List of potentially impaired waters, evaluating pollutant loading to lakes, 

and modeling lake function for FDEP’s TMDL Program. The data can also be used to document 

long-term water quality trends and provide general background information. However, they

cannot be used to verify impairment, nor can they be used in support of enforcement actions.

 11 Metadata consist of information about other data, including when and how the data were collected, by whom, and how they were 

formatted.
2008 Integrated Water Quality Assessment for Florida

64

Data gathered during periods that are not representative of the general health of the waterbody 

(e.g., during or immediately after a hurricane that can be tied to a short-term event, such as a 

spill) are flagged for further evaluation before being added to the IWR database. 

How Data Are Used To Make Attainment Determinations

Once the data have been screened and validated, they are evaluated to determine whether 

individual segments with waterbody identification numbers (WBIDs) are attaining their 

designated uses. Different analytical approaches, such as statistical analyses, are used to infer 

conditions from all valid data. Appendix B provides a detailed description of the IWR 

methodology.

Results of Statewide Basin Assessments

For the purposes of this assessment, there are two different types of total waters: total waters 

in the state and total waters assessed. FDEP keeps track of total waters in the state with a 

waterbody identification system, which includes 6,243 waterbodies that are characterized by 

waterbody type (rivers/streams, lakes, estuaries, or coastal waters). These comprise 

hydrologically unique pieces of rivers and streams, lakes, and estuaries with homogeneous 

water quality. Typically, the river and stream segments are about 5 miles long (generally 

bounded by headwaters, river mouths, or major intersecting streams); the estuary segments are 

about 5 square miles in size (often bounded by bridges); and lake segments comprise

approximately 60 acres each (usually entire lakes, but if a lake is very large or has distinct areas 

of water quality, it may be subdivided).

The assessed waters include those waters for which enough information is available to 

determine whether they attain their designated use (Category 2 under the EPA’s integrated 

assessment) or do not attain their designated use (EPA Categories 3c, 4a, 4b, 4c, 4d, 4e, and 

5). Table 14 lists the number and size of waters assessed for each waterbody type, and Table 

15 lists the size of the surface waters assigned to each of the EPA reporting categories.

For the determination of use support in this report, FDEP assessed 20,285 miles of rivers and 

streams, 1,495,972 acres of lakes, 3,726 square miles of estuaries, and 6,700 square miles of 

coastal waters using the IWR methodology for the Verified List of impaired waters. It should be 

noted that the assessment results for lakes are highly affected by the assessment results for

one impaired lake, Lake Okeechobee, which is by far the largest lake in the state. All estuaries 

and coastal waters have been assessed for mercury, and consumption advisories have been 

issued for a number of fish species because of excessive concentrations of mercury in fish 

tissue.

Table 14. Waters Assessed for the Statewide Basin Assessments,

by Waterbody Type

Waterbody Type

Number of 

Waterbody 

Segments

Assessed

Rivers/streams 3,969 20,285 miles

Lakes 1,303 1,495,972 acres

Estuaries 559 3,726 square miles

Coastal Waters 155 6,700 square miles

Note: Scale is 1:24,000. 

Source: National Hydrologic Dataset (NHD).
2008 Integrated Water Quality Assessment for Florida

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Table 15. Size of Surface Waters Assigned to Each EPA Integrated Report Category

Waterbody Type Category 

2*

Categories 

3c and 3d 

(Planning 

List)*

Category 

4*

Category 

5* No Data Insufficient Data

Total 

Waters 

Assessed

Total in 

State

Rivers/streams 

(miles) 1,538 2,828 120 6,365 7,656 1,779 20,285 20,285

Lakes (acres) 51,273 197,185 684 960,942 203,856 82,033 1,495,972 1,495,972

Estuaries 

(square miles) 48 0 0 3,659 18 0 3,726 3,726

Coastal Waters 

(square miles) 57 5 0 6,700 0 0 6,700 6,700

Note: There are no waters in EPA Category 1 (attaining all designated uses) because FDEP does not sample for all uses. 

Category 2 comprises waters attaining all the uses that are sampled for.

– Not applicable.

*The EPA’s Integrated Report categories are as follows:

1—Attains all designated uses;

2—Attains some designated uses;

3a—No data and information are available to determine if any designated use is attained;

3b—Some data and information are available, but they are insufficient for determining if any designated use is attained;

3c—Meets Planning List criteria and is potentially impaired for one or more designated uses;

3d—Meets Verified List criteria and is potentially impaired for one or more designated uses;

4—Impaired for one or more designated uses, but a TMDL will not be developed at this time for various reasons (See Table 

9); 

and

5—Water quality standards are not attained and a TMDL is required.

Summaries of Designated Use Support for Rivers/Streams, Lakes, Estuaries, and 

Coastal Waters

Table 16 summarizes support for designated use (class) for the rivers/streams, lakes, estuaries, 

and coastal waters assessed in the Florida basins, as follows:

• Class 1 waters (potable water supplies): 16% of river/stream miles assessed 

supported their designated use, compared with 0% of lake acres.

• Class II waters (shellfish propagation or harvesting): 0% of river/stream miles

and 0% of estuarine square miles assessed supported their designated uses.

• Class III fresh waters (recreation, propagation, and maintenance of a healthy, 

well-balanced population of fish and wildlife): 7% of river/stream miles and 5% 

of lake acres assessed supported their designated use.

• Class III marine waters (recreation, propagation, and maintenance of a healthy, 

well-balanced population of fish and wildlife): 2% of estuarine square miles and 

0% of coastal square miles assessed supported their designated use.
2008 Integrated Water Quality Assessment for Florida

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Table 16. Individual Designated Use Support Summary

Designated

Use

(Class)1, 2

Waterbody 

Type

Total in 

State

Total 

Assessed

Supports 

Designated 

Use

(Category 

2)

% 

Supporting 

Designated 

Use

Insufficient 

Data

(Categories 

3a, 3b, and 

3c)

Does Not 

Support 

Designated 

Use

(Categories 

4 and 5)

% Not 

Supporting 

Designated 

Use

I Rivers/streams 

(miles) 470 470 77 16% 186 207 44%

Lakes (acres) 502,579 502,579 0 0% 11,726 490,853 97%

II Rivers/streams 

(miles) 357 357 3 0% 205 149 41%

Estuaries 

(square miles) 1,516 1,516 0 0% 0 1,516 100%

IIIF Rivers/streams 

(miles) 19,364 19,364 1,457 7% 11,849 6,057 31%

IIIF Lakes (acres) 993,362 993,362 51,273 5% 471,348 470,762 47%

IIIM Estuaries 

(square miles) 2,155 2,155 48 2% 19 2,088 96%

IIIM Coastal waters 

(square miles) 6,700 6,700 0 0% 0 6,700 100%

1 Class I Potable water supplies

 Class II Shellfish propagation or harvesting

 Class III Recreation, propagation, and maintenance of a healthy, well-balanced population of fish and wildlife

 Class IV Agricultural water supplies (large agricultural lands, located mainly around Lake Okeechobee)

 Class V Navigation, utility, and industrial use (there are no state waters currently in this class)

2 F = Fresh water; M = Marine

3 Lake Okeechobee, a Class 1 waterbody, was designated as impaired by the Florida legislature in 1999, and FDEP 

completed and adopted by rule a TMDL for total phosphorus for the lake in 2001. The entire TMDL (140 metric tons/year) is 

allocated to nonpoint sources. This is based on an in-lake target restoration goal of 40 parts per billion (ppb). Lake 

Okeechobee has subsequently been verified as impaired for coliform bacteria, DO, and un-ionized ammonia.

Table 17 summarizes the size of waters impaired by various causes for each waterbody type; 

the principal causes of impairment are as follows:

• Out of 1,294 river/stream segments assessed: fish advisories for mercury, DO, 

fecal coliform, iron, and chlorophyll.

• Out of 654 lake segments assessed: fish advisories for mercury, TSI, DO, iron, 

and historical TSI.

• Out of 549 estuarine segments assessed: fish advisories for mercury, fecal 

coliform, DO, and chlorophyll.

• Out of 155 coastal segments assessed: fish advisories for mercury, and fecal 

coliform.
2008 Integrated Water Quality Assessment for Florida

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Table 17. Size of Waters Impaired by Causes

(Rivers/Streams, Lakes, Estuaries, and Coastal Waters)

Rivers/Streams

Parameter Number of 

Waterbodies

Miles 

Impaired

Dissolved Oxygen 248 2,328

Hg in Fish 243 2,935

Fecal Coliform 231 1,673

Nutrients 128 1049

Iron 35 668

Lead 14 131

Un-ionized 

Ammonia 11 75

Turbidity 7 81

Biology 4 29

Dissolved Solids 3 52

BOD 5Day 2 17

Copper 2 18

Cadmium 1 24

Malathion 1 8

Selenium 1 24

Lakes

Parameter Number of 

Waterbodies

Acres

Impaired

Nutrients 157 349,248

Hg in Fish 113 853,621

Dissolved Oxygen 41 116,324

Lead 9 9,388

Un-ionized 

Ammonia 8 11,640

Fecal Coliform 6 6,079

Iron 5 54,990

Turbidity 3 496

Copper 2 481

Cadmium 1 3761

Silver 1 7,428

 Estuaries

Parameter Number of 

Waterbodies

Square 

Miles 

Impaired

Hg in Fish 539 3,635

Nutrients 94 902

Dissolved Oxygen 83 620

Fecal Coliform 66 761

Copper 20 235

Iron 15 140

Fish Advisories 14 328

Lead 5 36

Nickel 5 88

Arsenic 3 20

BOD 5Day 1 38

Biology 1 4

Turbidity 1 1

 Coastal Waters

Parameter Number of 

Waterbodies

Square 

Miles 

Impaired

Hg in Fish 155 6,700

Copper 9 93

Fish Advisories 3 107

Fecal Coliform 3 423

Chlorophyll 1 102
2008 Integrated Water Quality Assessment for Florida

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303(d) List of Verified Impaired Waters

The 1998 303(d) list and the adopted 303(d) lists (Verified Lists) for 2002, 2003, 2004, 2005, 

2006, and 2007 (Basin Groups 1–5, respectively) are available on FDEP’s TMDL Program 

website at http://www.dep.state.fl.us/water/tmdl/index.htm. 

The website also contains information on the adopted lists of waters to be delisted (i.e., 

removed) from the 1998 303(d) list for the Group 1–5 basins. If use attainment is verified for a 

waterbody or segment that was previously listed as impaired, FDEP can propose that it be 

delisted. If attainment is verified for some designated uses of a waterbody or segment, FDEP 

will propose partial delisting for the uses attained. Future monitoring will be recommended to 

determine if remaining uses are attained.

Waters may also be delisted for other reasons, such as sufficient data to assess potential 

impairment, flaws in the original analysis, or impairment due to natural causes (such as low 

DO). The Comments column in each table explains the reason for proposing a segment for 

delisting.

During the first cycle of the basin rotation, and continuing in the second cycle, those waters that 

had originally appeared on the 1998 303(d) list submitted to the EPA were assessed using the 

methodology of the IWR.

As a result of the assessments performed during the first cycle of the basin rotation, 1998 

303(d) listed waters were either verified as impaired (which then required that TMDLs be 

developed); or verified as not impaired, in which case they were proposed for delisting (those 

waters without sufficient data with which to perform an assessment during the first cycle remain 

on the 1998 303[d] list maintained by the EPA). Those 1998 303(d) listed waters that the 

Department was unable to assess due to various circumstances related to data collection 

remain as part of the 303(d) list of impaired waters for the State

The 1998 303(d) list and the adopted State of Florida List of Verified Waters for 2002, 2003, 

2004, 2005, 2006, and 2007 (corresponding to Basin Groups 1–5 for Cycle 1 of the Basin 

Rotation and Basin Group 1 for Cycle 2) are available on the FDEP TMDL Program website 

(http://www.dep.state.fl.us/water/tmdl/index.htm). 

Delisting

In addition to the group-specific Verified Lists of Impaired Waters, the FDEP’s TMDL website 

also includes information on the group-specific lists of waters to be delisted. 

There are a variety of reasons for which FDEP may propose that a previously listed water 

segment be delisted (e.g., waters may be delisted if it is determined that the original listing was 

in error; or if it can be demonstrated that water quality criteria are currently being met for a 

waterbody or segment/analyte combination that was previously included on either the 1998 

303[d] list, or on the State of Florida’s Verified List of Impaired Waters). 

The EPA’s Office of Research and Development released the “National Coastal Condition 

Report II” in December 2004 (EPA-620/R-03/002). This report uses the readily available data to 

assess the ecological condition of the nation’s estuaries and coastal waters. EPA applied five 

indicators (dissolved oxygen, chlorophyll a, nitrogen, phosphorus, and water clarity) separately 
2008 Integrated Water Quality Assessment for Florida

69

and also in combination (to create a Water Quality Index). The FDEP will use these tools to 

assess the health of its’ coastal and estuarine waters. For example, in the Gulf Coast waters 

(excluding Florida Bay) the EPA has set a threshold of <5 ug/L for Chlorophyll a as indicating 

“Good” conditions. Waters with Chlorophyll a concentrations from 5-20 ug/L are considered to 

be in “Fair” condition. In addition, the report’s composite Water Quality Index allows any one of 

the five indicators to fall into the Fair range and still have an overall call of “Good” for that 

waterbody if the remaining four metrics are all in the “Good” part of their respective ranges. 

The flow chart below shows another part of the decision process for delisting waters listed for 

nutrient-related problems. For those analytes where the assessment decisions are based on 

the number of exceedances of numeric water quality criteria, the decision to list (or delist) is 

specified in the IWR; however, listing (and delisting) decisions for nutrients are not based on 

such numeric criteria and, consequently, the EPA has requested that those decisions include 

site-specific analyses. The site-specific approach to make delisting decisions for nutrient 

assessments relies on the use of the period of record data available for the listed waterbody.

For waterbodies that were included on the 1998 303(d) list [included using data from the 1996 

305(b)] report, available data are reviewed for the period prior to 1996. When data from the 

period of record used to support current IWR assessments show no evidence of increased 

chlorophyll a concentrations over the historic period, that waterbody is proposed for delisting. 

However, when historical data may show evidence to support the original listing, the period of 

record is further examined to determine a baseline threshold for chlorophyll values. When 

current assessment data for a waterbody previously listed for “Nutrients,” either on the 1998 

303(d) or from the Verified List developed during the first cycle of the basin rotation, show no 

increase over these historical threshold values, these waters are also proposed for delisting.

Any waters that do not have sufficient data to be analyzed in accordance with the requirements 

of the IWR will remain on the 1998 303(d) list of impaired waters maintained by the EPA. These 

waters are not delisted, and they will be sampled during the next phases of the watershed 

management cycle so that their impairment status can be verified.
2008 Integrated Water Quality Assessment for Florida

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Status of Total Maximum Daily Load Development

There are two different schedules for TMDL development. The initial listing of impaired waters 

in 1998 was incorporated into a 1999 Consent Decree between the EPA and Earthjustice—to 

which Florida was not a party—that imposed a 13-year schedule for the development of more 

than 2,000 specific TMDLs in Florida. These “consent decree waters” were assigned either a 

high or low priority, and the judge established a schedule for completing TMDLs for these 

waters or delisting them. If the state does not meet the deadline, then the EPA is responsible 

for developing the TMDL to meet the deadline. For the upcoming 2-year period, as part of the 

rotating basin approach, FDEP will evaluate all available data, with particular emphasis on the 

consent decree listed waters, contained in its Group 1 and Group 2 basins. TMDLs will be 

developed for those verified impaired waters, as scheduled under the terms of the consent 

decree.

For waters verified as impaired through the TMDL process, adopted by Secretarial Order, and 

approved by the EPA, the state must develop TMDLs or list the impairment as a natural 

condition. There is no court-mandated completion date. Instead, these impaired waters are 

ranked as low, medium, and high priority, with no scheduled year for completion. Under Section 

62-303.500, F.A.C., the prioritization is carried out according to the severity of the impairment 

and each segment’s designated uses, taking into account the most serious water quality 

problems; most valuable and threatened resources; and risk to human health and aquatic life.

High-priority waters are those where the impairment poses a threat to potable water supplies or 

to human health, or where it is due to a pollutant regulated by the Clean Water Act and the 

pollutant has contributed to the decline or extirpation of a federally listed threatened or 

endangered species. Low priority waters are those listed due to fish consumption advisories for 

mercury (due to the current insufficient understanding of mercury cycling in the environment); 

man-made canals, urban drainage ditches, and other artificial segments that are listed only 

because they exceed the DO criterion; and segments that were not on the Planning List, but 

were subsequently identified as impaired and placed on the Verified List.

All “nonconsent decree waters” not designated high or low priority are medium priority and are 

prioritized based on a number of factors, including the presence of OFWs; the presence of 

segments that fail to meet more than one designated use; the presence of segments that 

exceed an applicable water quality criterion or alternative threshold with more than 25% percent 

of the samples not meeting an applicable water quality criterion or alternative threshold 

exceedance frequency with a minimum of a 90% confidence level; the presence of segments 

that exceed more than one applicable water quality criterion; and the administrative needs of the 

TMDL Program, including the TMDL development schedule agreed to with the EPA, basin 

priorities related to following FDEP’s watershed management approach, and the number of 

administratively continued permits in the basin. TMDLs for nonconsent decree TMDLs will be 

developed in association with those on the consent decree, when feasible. Other nonconsent 

decree TMDLs will be complete within the suggested time frames in the EPA’s policy 

documents.

With 100% of the state evaluated, approximately 2,565 TMDLs will be required for 1,688 Florida 

waters. Because TMDLs are developed for individual pollutants, a waterbody may have 

multiple TMDLs. To date, FDEP has developed, proposed, or adopted 322 TMDLs for 166 

waterbodies, and 3 BMAPs have been completed and adopted (for the Upper Ocklawaha River 

Basin, Orange Creek, and Long Branch).
2008 Integrated Water Quality Assessment for Florida

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Figure 5 illustrates the statewide assessment results for all parameters, excluding mercury. 

The figure illustrates the fact that most surface water quality problems are found in highly 

urbanized central and south Florida. Problems are evident around the densely populated, major 

urban centers, including Jacksonville, Orlando, Tampa, Pensacola, Cape Kennedy, and the 

southeastern Florida coast. Basins with intense agricultural and industrial use are also 

associated with poor water quality. Water quality in the northwest and west-central sections of 

the state is generally better than in other areas.

Figure 6 summarizes the assessment results for mercury. As noted earlier, in many Florida 

waters consumption advisories have been issued for a number of fish species. Mercury as a

human health issue is considered to be a lower priority for TMDL development, and mercury 

has been removed from the priority section of the IWR. FDEP will develop statewide TMDLs for

both fresh waters and marine waters that are impaired for mercury; the TMDLs are due by 

September 2012.

Figure 5. Results of Florida’s Surface Water Quality Assessment

for all Parameters (Excluding Mercury)

Biology. The IWR relies heavily on stream biological data for impairment status. Since 1992,

FDEP has taken about 700 BioReconnaissance (BioRecon) and about 1,600 SCI 
2008 Integrated Water Quality Assessment for Florida

72

measurements. Over this period, BioRecons statewide showed a 27% stream failure rate, and 

13% of the SCIs failed. Table 18 shows the numbers of measurements and impairment status 

for the BioRecon and SCI from 1992 to June, 2004.

Use of Historical Data

For data older than 10 years prior to the time of the assessment, the FDEP considers all readily 

available data. As part of the IWR programming, all assessment units (WBIDs) are flagged to 

note whether or not older data exist for that WBID. (If an assessment call can be made using 

the data from the Planning or Verified Periods, these older data are not evaluated, as newer 

data supersedes older data.) In cases where an assessment call cannot be made using the 

data from the Planning or the Verified Periods, FDEP staff review all data and information in our 

databases that relate to the pollutant of concern. Making quality assurance (QA) checks for 

data provided by sources other than the FDEP has proven difficult, as metadata from these 

sources are often not maintained for older data. FDEP generated data are also subject to QA 

reviews and are not used for assessment purposes if they fail the requisite QA tests. Based 

upon our review of older data provided by agencies outside the agency, FDEP has determined 

that only those data generated by the FDEP’s laboratories and those data from outside 

agencies that have accompanying metadata will be used to supplement data from the Planning 

and Verified Periods.
2008 Integrated Water Quality Assessment for Florida

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Figure 6. Results of Florida’s Surface Water Quality Assessment for Mercury

Table 18. Numbers of Measurements and Impairment Status

for the BioRecon and SCI, 1992–June 2004

Biological Test Call Impairment Number of 

Measurements

BioRecon Healthy Not impaired 280

BioRecon Pass Not impaired 1

BioRecon Suspect Not impaired 245

BioRecon Impaired Impaired 188

BioRecon Fail Impaired 3

SCI Excellent Not impaired 1,041

SCI Good Not impaired 383

SCI Poor Impaired 172

SCI Very Poor Impaired 39
2008 Integrated Water Quality Assessment for Florida

74

Trend Analysis for Rivers/Streams, Lakes, Estuaries, and Coastal Waters

Changes in water quality over time are an important indicator of the health of surface waters. 

Table 19 shows trends in water quality for chlorophyll a, nitrogen, and phosphorus in 

rivers/streams, lakes, estuaries, and coastal waters from 1997 to 2007. Enough data were 

available to evaluate long-term trends in water quality for 823 rivers/streams, lakes, estuaries, 

and coastal waters. Overall, most (about 54%) showed no significant trends, while 22% 

improved and 24% worsened.

Table 19. Trends in Water Quality for 

Rivers/Streams, Lakes, Estuaries, and 

Coastal Waters, 1997–2007

Description Number of 

Waterbodies Miles or Area

Rivers/Streams Assessed for Trends 

(miles)

Improving 44 447

Stable 221 2,531

Degrading 75 894

Fluctuating 0 0

Trend 

Unknown 3,629 16,413

Lakes Assessed for Trends 

(acres)

Improving 92 129,659

Stable 141 401,210

Degrading 116 391,907

Fluctuating 0 0

Trend 

Unknown 954 573,196

Estuaries Assessed for Trends

(square miles)

Improving 41 752

Stable 76 796

Degrading 9 135

Fluctuating 0 0

Trend 

Unknown 433 2,042

Coastal Waters Assessed for Trends 

(square miles)

Improving 1 32

Stable 1 102

Degrading 0 0

Fluctuating 0 0

Trend 

Unknown 155 6,567
2008 Integrated Water Quality Assessment for Florida

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Special Focus: Lake Issues

Lakes are a particular focus of the EPA’s 2008 Integrated Report guidance. This section 

provides information on lake trends, lake trophic status, approaches to controlling lake pollution 

and lake water quality, approaches to mitigating high acidity in lakes, and publicly owned lakes 

with impaired uses. Table 16 summarizes support for designated use (class) for lakes, and 

Table 17 provides information on the acres of lakes impaired by various causes.

Lake Trends. Trends in Florida lakes between 1997 and 2007 were analyzed, and there were 

sufficient data for trend analysis for 349 lakes. Of these 349 lakes, 92 were improving, 141 

were stable, and 116 were degrading (Table 19). For 954 lakes, trends were unknown.

Trend analysis was accomplished using quarterly waterbody medians of nitrogen, phosphorus 

and chlorophyll for the 1997–2007 period. Only waterbodies with at least 10 or 11 years of data 

were used in the Spearman rank-order nonparametric correlation (correlations had to be 

significant at the 95% confidence level). 

Lake Trophic Status. Table 20 lists the trophic status of significant publicly owned lakes in the 

state. The table shows that of 1,137,729 acres of lakes assessed (or about 76% of the lake 

acres in Florida), 87% are eutrophic and another 4% are hypereutrophic.

Table 20. Trophic Status of Significant 

Publicly Owned Lakes

Description Number of 

Lakes Acres of Lakes

Total in State 1,303 1,495,972

Assessed 669 1,137,729

Eutrophic 434 988,346

Hypereutrophic 13 46,474

Mesotrophic 209 97,904

Oligotrophic 13 5,005

Dystrophic 0 0

Unknown 634 358.243

Note: Results are based on the TSI for 1996–2007.

TSI values for lakes are as follows:

Oligotrophic – < 20

Mesotrophic – 20 to < 40

Eutrophic – 40 to < 80

Hypereutrophic – ≥ 80

Approaches to Controlling Lake Pollution and Lake Water Quality. The TMDL assessment 

process described earlier in this chapter provides an approach to controlling the point and 

nonpoint source pollution entering Florida’s lakes and restoring lake water quality. In particular, 

the Basin Management Action Plans (BMAPs) developed for impaired waterbodies contain 

specific management activities and BMPs for reducing pollution. Each BMAP also provides

interim and final targets for evaluating water quality improvements, a mechanism for tracking the 

implementation of management actions, procedures for monitoring and reporting on progress, 

data management and QA/QC procedures, a description of methods used to evaluate progress 

towards goals, a strategy and schedule for periodically reporting results to the public, and 
2008 Integrated Water Quality Assessment for Florida

76

procedures to determine whether additional corrective actions are needed and whether plan 

components need to be revised.

Approaches to Mitigating High Acidity in Lakes. High acidity in lakes is not generally 

considered to be a problem in Florida, because of naturally low pH due to swamp drainage and 

the low buffering capacity of swampy rainwater.

Publicly Owned Lakes with Impaired Uses. Florida has a number of publicly owned lakes 

that are known to be impaired. These include lakes that do not meet applicable WQSs or that 

require the implementation of control programs to maintain compliance with applicable 

standards. Appendix D lists alphabetically the impaired lakes in the state, the parameter 

causing impairment, the basin group, and the river basin within which each lake is located.

Drinking Water

Surface waters supply only about 13% of Florida's drinking water. Of 7,200 public drinking 

water systems statewide, 19 obtain their water from surface water. An additional 26 systems 

wholly or partially purchase water from these 19 systems. Because it is expensive to operate a 

surface water system (given that filtration and advanced disinfection are costly), most are large.

While earlier sections of this chapter discussed impaired waters by waterbody type, this section 

provides assessment results specifically for drinking water use attainment. To determine 

attainment for drinking water use, the data for all Class I rivers/streams and lakes in the state 

were assessed. Class I waters must also protect general human health, aquatic life, and allow 

for the protection of fish and wildlife, as well as recreational uses.

Table 21 lists the total miles of rivers/streams and acres of lakes/reservoirs designated for 

drinking water use in Florida (470 miles and 433,280 acres, respectively). For waters 

designated for drinking water use, Table 22 lists the miles of rivers/streams and acres of 

lakes/reservoirs designated for drinking water use that are assigned to each of the EPA’s five 

reporting categories. Table 17, which summarizes the causes and acreages of waterbodies not 

attaining drinking water use for rivers/streams and lakes (i.e., Class I waters), shows that 16% 

of rivers and streams, and 1% of lakes, supported drinking water use.

Table 21. Total Miles of Rivers/Streams 

and Acres of Lakes/Reservoirs 

Designated for Drinking Water Use

Waterbody 

Type Number Total in State

Streams 81 470 miles

Lakes 22 433,280 acres
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Table 22. Miles of Rivers/Streams and Acres of Lakes/Reservoirs

Designated for Drinking Water Use that Are Assigned to Each of 

the EPA’s Five Reporting Categories

Waterbody Type Number of 

Waterbodies

Stream Miles 

and Lake Acres EPA Category* Assessment Status

Rivers/Streams 9 77 2 Meets use

Rivers/Streams 28 111 3a No data

Rivers/Streams 10 33 3b Insufficient data

Rivers/Streams 8 42 3c Planning List

Rivers/Streams 25 207 5 Verified List

Lakes 0 0 2 Meets use

Lakes 2 10,174 3a No data

Lakes 2 1,551 3c Planning List

Lakes 19 490,852 5 Verified List

*The EPA’s Integrated Report categories are as follows:

1—Attains all designated uses;

2—Attains some designated uses;

3a—No data and information are available to determine if any designated use is attained;

3b—Some data and information are available, but they are insufficient for determining if any designated use is 

attained;

3c—Meets Planning List criteria and is potentially impaired for one or more designated uses;

3d—Meets Verified List criteria and is potentially impaired for one or more designated uses;

4—Impaired for one or more designated uses, but a TMDL will not be developed at this time for various reasons 

(See Table 9); and

5—Water quality standards are not attained and a TMDL is required.

Overlap of Source Water Areas and Impaired Surface Waters. Verified Lists of impaired 

surface waters have been adopted for the Group 1–5 basins. Several waters were listed based 

on parameter concentrations that may pose a public health concern to public water systems, 

and in several instances these coincide with source water assessment and protection areas for 

community water system surface water intakes. Source water areas were modeled based on a 

3-day travel time to the intake within surface waters and their 100-year floodplains. Streams 

were added to the source water coverage from USGS quadrangles, with a 3-meter buffer 

around each one. The overlap of impaired surface waters and these source water areas were

determined using the source water coverage, the lists of impaired surface waters, the areas of 

Florida’s lakes and reservoirs, and the 1:24,000-scale NHD for streams. 

Table 23 summarizes the findings for the Group 1–5 basins. The table shows the aggregate 

miles of rivers/streams and acres of lakes/reservoirs representing an overlap between source 

water areas and surface waters that are listed for primary drinking water parameters. This

summary includes segments of 15 waterbodies that were listed for fecal coliform. Public water 

systems in Florida are required to perform chlorination treatment to address bacteria. 
2008 Integrated Water Quality Assessment for Florida

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Table 23. Summary of Impaired River/Stream Miles and 

Lake/Reservoir Areas Overlapping Source Water Areas of 

Community Water Systems

Surface Water Type

Length or Area of Impaired Surface 

Waters Overlapping Source Water 

Areas in Groups 1-5

Percent of Total Length 

or Area in Groups 1-5

Streams and Rivers 584 miles 1.15%

Lakes/Reservoirs 1,478 acres 0.094%

Note: The analysis is based on adopted lists of impaired surface waters for the Group 1–5 basins. 

Parameter of interest was fecal coliform.

Freshwater, Estuarine, and Marine Sediment Contamination

Freshwater Sediments. In healthy aquatic environments, sediments provide critical habitat for 

many organisms. However, sediments can also accumulate contaminants. Knowledge of 

existing sediment quality is important for environmental managers, especially in restoration and 

dredging projects, but periodic water quality monitoring cannot fully assess aquatic ecosystems, 

as it is not usually designed to assess the cumulative impact of contaminants.

Unlike water, there are no sediment standards. Tools have been designed to evaluate sediment 

quality. In 2002, FDEP released a Web-assisted statistical tool that evaluates metals 

enrichment in freshwater sediments. The tool estimates anthropogenic impacts by comparing 

sediment metal contaminants with both aluminum and iron in the sediment. Furthermore, in 

2003, FDEP released the document, Development and Evaluation of Numerical Sediment 

Quality Assessment Guidelines for Florida Inland Waters, which provides guidance in the 

interpretation of freshwater sediment contaminant data as it relates to biological impacts at a 

site. The report contains freshwater sediment guidelines that are based on the same weight-ofevidence statistical approach used to develop the 1994 coastal sediment quality guidelines 

(discussed in the following estuarine assessment section). Each metal and organic contaminant 

has two guidelines, a lower guideline that informs managers that contaminant-induced harm 

may occur, and a higher guideline that informs managers that biological harm will most likely 

occur due to elevated contaminant concentrations. These interpretive documents are available 

at http://www.dep.state.fl.us/water/monitoring/index.htm#seds.

In 2004, FDEP, in conjunction with two water management districts (North Florida and St. Johns 

River), conducted a survey of sediments from both large and small lakes in the 6 Group 1 

basins. A total of 284 lake sediment samples was collected after the collection of the water 

samples. FDEP’s Central Laboratory analyzed these samples for metals, nutrients, and organic 

contaminants. Metals analyzed included arsenic, cadmium, chromium, copper, lead, nickel, 

mercury, silver, and zinc; organic contaminants included polynuclear hydrocarbons (PAHs), 

polychlorinated biphenyls (PCBs), and organochlorine pesticides (for example, DDT and its 

breakdown products). FDEP’s Monitoring Section then applied the sediment quality 

assessment tools to the resulting dataset. 

Using the two guidelines in the 2003 guidelines document, it is apparent that the metals copper, 

lead, and zinc produce the most exceedances of both the lower and higher guidelines. Arsenic, 

cadmium, chromium, and mercury rarely exceed the higher guideline, but do commonly exceed 

the lower guideline. Not surprisingly, sediment metals were highest in lakes in urbanized areas, 
2008 Integrated Water Quality Assessment for Florida

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with the highest number of samples that show elevated metals collected in the Tampa Bay

region.

In the 284 samples, there were 41 detections of an organic contaminant; however, some 

sediment samples had detections of more than 1 individual organic contaminant. No PCB 

compounds were detected, and only 7 samples had detectable amounts of PAHs. However, the 

persistent organochlorine pesticides DDT (along with its breakdown products, DDD and DDE) 

and chlordane were detected at 20 stations. The two Group 1 basins with the most

exceedances of the higher organic contaminant guideline were the Ocklawaha River Basin, 

which is heavily agricultural, and the urban Tampa Bay Basin. Chlordane, a now-banned but 

formerly widely used termiticide, was detected in 7 lake sediment samples, all in the Tampa Bay 

Basin.

Estuarine and Marine Sediments. Florida’s unique geologic and hydrologic features make its 

surface water and ground water relatively vulnerable to contamination. Sediment and soil 

contamination is particularly important to water quality, because surface and subsurface 

sediments, ground water, and surface water interact extensively. Sediment contamination is 

also crucial because of the state’s extensive estuaries and their use as commercial and 

recreational fisheries.

Although Florida currently has no criteria for heavy metals or toxic organics in sediments, FDEP 

studied estuarine sediments to assess current conditions, develop tools to identify contaminated 

areas, and provide background information to develop future sediment criteria.

The initial study collected and interpreted data on natural background concentrations of selected 

metals, including arsenic, cadmium, chromium, copper, mercury, lead, zinc, cadmium, barium, 

iron, lithium, manganese, silver, titanium, and vanadium.

l

 The study was later expanded to 

include five classes of organic contaminants: chlorinated hydrocarbons (pesticides), polycyclic 

aromatic hydrocarbons, polychlorinated biphenyls, phenolic hydrocarbons, and aliphatic 

hydrocarbons.m

Once the data were collected, the group developed tools using metal-to-aluminum ratios to 

identify estuarine and marine sites contaminated with cadmium, lead, arsenic, zinc, lead, nickel, 

chromium, and copper. Ratios greater than 1 indicate potential contamination. Mercury was 

evaluated against a maximum concentration associated with uncontaminated estuarine 

sediments. Metal contamination above background levels was most often seen for cadmium, 

mercury, lead, and zinc. Polycyclic aromatic hydrocarbons were found in about 70% of the 

samples tested for organic chemicals. Of this group, fluoranthene and pyrene were found in 

The sediment database contains information collected from 700 sites by FDEP, 42 sites by the 

National Oceanic and Atmospheric Administration's National Status and Trends Program, and 

33 sites in the St. Johns River by Mote Marine Laboratory (a private marine research facility in 

Sarasota). The data came from 3 different surveys. From 1983 to 1984, sediments were 

collected as part of the Deepwater Ports Project from sites near dense population centers and 

close to commercial channels and ship berths. A second survey, from 1985 to 1991, assessed 

sites where contamination was expected because of flows from tributaries and local land use 

practices. The third survey examined sites in relatively remote or unimpacted areas.

 l This effort culminated in the release of the document, A Guide to Interpretation of Metal Concentrations in Estuarine Sediments

(FDEP, April 1988).

m The expanded database is summarized in Florida Coastal Sediment Contaminants Atlas (FDEP, 1994).
2008 Integrated Water Quality Assessment for Florida

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more than 50% of the samples. Not surprisingly, more contaminants were found in urban 

watersheds than in rural or undeveloped watersheds.

While contaminant levels in estuarine and marine sediments can be measured, the effects of 

specific concentrations of metals or organic chemicals on aquatic life are not completely 

understood. Because of the difficulty of interpreting the data, FDEP developed guidelines for 

assessing sediment quality rather than sediment criteria. The guidelines provide ranges of 

concentrations that could cause a specific level or intensity of biological effects.

Using data from 20 different areas of Florida, FDEP developed preliminary guidelines for 34 

priority contaminants in coastal and marine sediments.n

 Data from acute toxicity tests were 

used mainly because little information exists on chronic effects. Three ranges of effects were 

defined for each contaminant: probable, possible, and minimal. These are interpreted, 

respectively, as concentrations that always have an effect, frequently have an effect, and rarely 

or never have an effect. The guidelines for 28 substances have a high or moderate degree of 

reliability. The guidelines for all 34 substances, used collectively, predict the potential effects of 

contaminated marine and estuarine sediments on biological communities.o

Public Health Concerns and Programs

Although the guidelines are a valuable tool, it is recommended that they be used with other tools 

and assessment procedures. Direct cause and effect should not be inferred. They also do not 

replace dredging disposal criteria or formal procedures, nor are they meant to be sediment 

quality criteria or numeric attainment levels for cleaning up Superfund sites.

Drinking Water

FDEP has the primary role of regulating public water systems in Florida, under Chapter 403, 

Part IV, F. S., and by delegation of the federal program from the EPA. To this end, FDEP has 

promulgated a number of rules in the Florida Administrative Code. The section entitled 

Overview of Ground Water Protection Programs in Chapter 2 describes FDEP’s ongoing efforts 

to protect drinking water supplies.

A public water system is one that provides water to 25 or more people for at least 60 days each 

year or serves 15 or more service connections. These public water systems may be publicly or 

privately owned and operated. Additional information is available at FDEP’s Drinking Water 

Program website at http://www.dep.state.fl.us/water/drinkingwater/index.htm.

FDOH and the county health departments regulate very small water systems that provide water 

for public consumption, but that do not fall under the definition of public water systems. 

Additional information is available on FDOH’s website at 

http://www.doh.state.fl.us/environment/water/index.html. The water management districts 

regulate the digging of water wells, both public and private, and the quantities of water that may 

be extracted.

 n This approach was adapted from recommendations by Long and Morgan, 1990.

o For a complete discussion of methodology, see MacDonald, 1994.
2008 Integrated Water Quality Assessment for Florida

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Bacterial and Mercury Contamination

Assessment results indicate that several human health-related designated uses are not always 

maintained in Florida’s surface waters. Specifically, primary contact and recreation use support 

and shellfish harvesting use support are sometimes limited by the presence of bacteria in the 

water column, and for a number of species in many waters across the state, fish consumption 

use support is commonly limited by the presence of mercury in fish tissue.

It is important to note, however, that these impairments are not based on documented impacts 

on public health. Florida has extensive monitoring programs that issue beach advisories, 

shellfish bed closures, and fish consumption advisories when ambient samples reach 

predetermined thresholds. These thresholds are conservatively designed to protect public 

health against the potential effects of exposure to bacteria (in water and shellfish) and mercury 

(in fish tissue).

FDEP’s mercury website at http://www.dep.state.fl.us/labs/mercury/index.htm provides 

information on the mercury issue and links to other useful websites dealing with mercury.

Information on the latest fish consumption advisories is available on FDOH’s website at

http://www.doh.state.fl.us/environment/community/fishconsumptionadvisories/index.html. 

Information on beach closures is available on FDOH’s website at 

http://esetappsdoh.doh.state.fl.us/irm00beachwater/default.aspx. Information on shellfish bed 

closures is available on FDACS website at 

http://www.floridaaquaculture.com/SEAS/SEAS_intro.htm.

Harmful Algal Blooms

Over the last several years, concern has grown in Florida about the potential public health threat 

from harmful algal blooms (HABs). In general, researchers believe that freshwater algal blooms 

are increasing in frequency, duration, and magnitude and therefore may be a significant threat 

to surface drinking water resources and recreational sites (Williams, April 14, 2004). Typically 

caused by excess nutrients, these blooms may produce toxins that can harm humans through 

exposure to contaminated fish, dermal contact, and even the inhalation of aerosols. 

Blue-green Algae

A relatively new issue of concern in Florida is the presence of the toxigenic blue-green algae 

called cyanobacteria and their production of cyanotoxins. Blooms of cyanobacteria are due, in 

most part, to high nutrient loads; slow-moving waters; and hot, humid, and stagnant conditions. 

Cyanotoxins are naturally produced chemicals that can cause liver, brain, and skin toxicity. 

Several cyanotoxins, namely microcystins and the lyngbyiatoxins, have been implicated as 

tumor promoters (Williams, April 14, 2004). Cyanobacteria were on the EPA’s1998 

Contaminant Candidate List (CCL), which is used to prioritize research and make regulatory 

determinations. Since the CCL was developed, the EPA has placed a number of the 

microcystin toxins on its “Unregulated Contaminant Monitoring Rule – List 3” for a more detailed 

investigation into these toxins’ occurrence and health impacts. Although no formal decision has 

been made to date, this nationwide monitoring would take place after 2005.

Potentially toxigenic cyanobacteria have been found statewide, including river and stream 

systems such as the St. Johns, Caloosahatchee, Peace, and Kissimmee Rivers. The 

Cyanobacteria Survey Project (1999–2001), managed by the Harmful Algal Bloom Task Force 
2008 Integrated Water Quality Assessment for Florida

82

at FMRI (now the Florida Fish and Wildlife Research Institute), indicated that the species of 

Microcystis, Anabaena, and Cylindrospermopsis were dominant, while Aphanizomenon, 

Planktothrix, Oscillatoria, and Lyngbya were also observed statewide but not as frequently. 

Cyanotoxins (microcystins, cylindrospermopsin, and anatoxin-a) were also found statewide. A 

quota of 25 samples was collected in each water management district.

A number of waterbodies in Florida have abundant populations of blue-green algae. These 

include Lakes Seminole and Tarpon in Pinellas County, Lakes Beauclair and Dora in Lake 

County, Newnans Lake in Alachua County, Lake Jesup in Seminole County, Lake Okeechobee 

in Okeechobee, Palm Beach, Hendry, and Glades Counties, and numerous others (Williams, 

April 14, 2004). The first demonstrated case in Florida of human dermatitis related to a 

freshwater cyanobacteria species, C. raciborskii, occurred in Winter Haven on Lake Cannon 

during the 1990s (J. King, FDEP, April 14, 2004, personal communication).

Frequently, measured concentrations of cyanotoxins have been reported in some postprocessed finished water of drinking water facilities in Florida. A few of these concentrations 

were above the suggested guideline levels. The Cyanobacteria Survey Project of 2000 focused 

on water treatment plants that produced drinking water from surface waters. Samples (raw and 

finished water) were collected once a month for approximately 9 months. On 6 occasions, 

microcystin levels (hepatotoxins) in finished water samples were reported above the 1 

microgram per liter (μg/L) World Health Organization (WHO) guideline level (a range of 1 to 10 

micrograms per liter [μg/L]). However, these guideline levels have a 1000x safety factor and are 

based on a lifetime exposure. Further, the sample deviation at these low concentrations raised 

the issue of quality assurance, particularly considering the use of new analytical procedures and 

lack of lab certification. 

There are no WHO guidelines for cylindrospermopsin (which is classified as a hepatotoxin, but 

is a more general tissue toxin) or anatoxin-a (a neurotoxin). However, Australia determined that 

1 μg/L for cylindrospermopsin was appropriate due to its genotoxic capabilities. The 

Cyanobacteria Survey Project found 9 samples of finished water that contained 

cylindrospermopsin levels between 8 and 97 μg/L. As for anatoxin-a, 2 samples contained 

levels from 2 to 8 μg/L, and 4 samples contained detectable levels but below an arbitrary level 

of 1 μg/L (C. Williams, GreenWater Laboratories/CyanoLab, April 14, 2004, personal 

communication). Again, quality assurance issues cause the results to be questionable. 

Since that study, FDOH has established a testing laboratory and certification program for these 

chemicals and is participating in additional studies of recreational and drinking waters. Several 

Drinking Water facilities are either monitoring for these substances or are participating in a 

larger study to evaluate the effectiveness of treatment methodologies to eliminate the toxins. 

Reports from WHO and other research around the world indicate that conventional treatment 

processes are effective at eliminating the algae and the toxin, when present. The taste, odor, 

and color associated with the bloom provide a clear indication of its presence and initiate the 

use of additional treatment. While these treatment techniques are being used to control the

taste, odor, and color of the water, they are also being shown to very effective at removing or 

degrading the toxins.

Consistent/persistent low levels of microcystins (0.1 to 1.0 μg/L) have been found in the Harris 

Chain of Lakes in central Florida and in Lake Okeechobee. Eutrophic waterbodies with high 

blue-green populations are likely to have consistent levels of toxins present, especially during 

the spring and summer months. Reports indicate that the greatest toxin production 
2008 Integrated Water Quality Assessment for Florida

83

(microcystins) is almost always during the late fall and early winter (Williams, April 14, 2004, 

personal communication).

Pfiesteria

Citizens near the Lower St. Johns River and St. Lucie River Estuary have expressed particular 

concern about potential blooms of Pfiesteria piscicida, which has been documented to cause 

ulcers in fish and respiratory irritation, skin rashes, and possible neurocognitive disorders in 

humans in the mid-Atlantic region. P. piscida has never been positively identified in the Lower 

St. Johns, but Pfiesteria-like organisms have been found. No Pfiesteria or Pfiesteria-like events 

have been documented in Florida. FMRI has also evaluated coastal waters for Pfiesteria, and 

no samples to date have contained this species.

Red Tide

The Florida Fish and Wildlife Research Institute (FWRI) in St. Petersburg monitors HABs as part 

of its ECOHAB (Ecology and Oceanography of Harmful Algal Blooms in Florida) program. This 

monitoring primarily focuses on red tide, a brevetoxin that has been linked to numerous marine 

mammal deaths (in manatees and dolphins) and can cause severe respiratory distress in 

people who are exposed to a strong red tide event. Additional information on red tide is 

available at FDACS’ website at http://www.floridaaquaculture.com/RedTide/RedTideInfo.htm.

Wetlands Program

Wetlands Inventory and Wetlands Protection

Florida does not assess attainment of designated use for wetlands as it does for rivers and 

streams, lakes, estuaries, and coastal waters, because water quality in wetlands is not routinely 

monitored. However, wetlands are often associated with rivers and lakes, which are routinely 

sampled. 

Although some background data are collected for issuing permits (particularly for wastewater 

discharged to wetlands) and restoration programs may require water quality data, Florida does 

not have a comprehensive wetlands monitoring network. This section provides an inventory of 

major wetlands and historical coverage of wetlands in the state, the development of wetlands 

water quality standards, and wetlands management and protection efforts.

Major Wetland Systems

Wetlands comprise almost one-third of the state. Because of its low elevation and peninsular 

nature, Florida has many varied types of wetlands, including estuarine and freshwater marshes, 

mangrove forests, cypress swamps, and riverine floodplain. The following are the largest and 

most important in the state:

• The Everglades and the adjacent Big Cypress Swamp. Including the Water 

Conservation Areas (diked portions of the original Everglades system) and 

excluding the developed coastal ridge, this system extends approximately from 

Lake Okeechobee to Florida Bay.
2008 Integrated Water Quality Assessment for Florida

84

• The Green Swamp in the state’s central plateau.

• The Big Bend coast from the St. Marks River to the (South) Withlacoochee 

River.

• Vast expanses of Spartina marsh between the Nassau and St. Mary’s Rivers.

• The system of the St. Johns River marshes. Before alteration by humans, all 

but the northernmost one-fifth of the river basin was an extensive freshwater 

system of swamps, marshes and lakes.p

• The headwaters and floodplains of many rivers throughout the state, especially 

the Apalachicola, Suwannee, St. Johns, Ocklawaha, Kissimmee, and Peace 

Rivers.

 Even today, half of the length of the 

St. Johns River is actually marsh, and in many respects it functions like a 

northern-flowing Everglades.

Historical Wetlands Coverage in Florida

Although information on the historical extent of Florida’s wetlands is limited, one researcher 

estimates that the state lost as many as 46% of its original wetlands between the 1780s and the 

1980s. Table 24 contains estimates of Florida’s historical wetlands at a number of different 

points in time.

Table 24. Historical Estimates of Wetlands in Florida, 1780–1980

Period Wetlands Acreage Source

circa 1780 20,325,013 Dahl, 1990

mid-1950s 12,779,000 Hefner, 1986

mid-1970s 11,334,000 Hefner, 1986

mid-1970s 11,298,600 Frayer and Hefner, 

1991

1979–80 11,854,822 Tiner, 1984

circa 1980 11,038,300 Dahl, 1990

What is notable about the table above is that the rate of wetland loss appears to have 

significantly slowed since the mid-1970s, corresponding to when federal and state dredge-andfill regulatory programs were enacted. Another point to keep in mind is that there is no single, 

current, comprehensive way to estimate the wetland acreage in Florida. The state uses its own 

wetland delineation methodology, which has been adopted as Rule 62-340, F.A.C. This 

methodology, used by all state and local agencies throughout the state, requires field-based, 

site-specific determinations on a case-by-case basis—including an assessment of on-site soils, 

hydrology, and vegetation (as such, wetland estimates cannot be determined based on aerial 

surveys or mapping). The methodology is similar, but not identical, to the 1987 Manual 

methodology used by the U. S. Army Corps of Engineers. Further, many of the estimates in the 

table are based on the rather crude National Wetlands Inventory, which has not been groundtruthed and does not directly correspond to either the state or the Corps’ methodology.

 p Kushlan, 1990.
2008 Integrated Water Quality Assessment for Florida

85

Development of Wetlands Water Quality Standards

Since most wetlands are considered waters of the state,q they are regulated under the same 

standards as other surface waters, and the same five functional classifications described earlier 

also apply. The state's antidegradation rules are set out in Sections 62-302.300 and 62-4.242, 

F.A.C. Statutory authority for regulating impacts to wetlands and other surface waters is set 

forth in Part IV, Chapter 373, F.S. Rules regulating impacts to wetlands and other surface 

waters have been adopted under that authority by FDEP and the state’s five water management 

districts. These include Rule 62-312, F.A.C., which covers the Florida Panhandle, and Rules 

62-330, 62-341, 62-343, 40A-4, 40B-4, 40B-400, 40C-4, 40C-40, 40C-41, 40C-400, 40D-4, 

40D-40, 40D-400, 40E-4, 40E-40, 40E-41, and 40E-400, F.A.C. A requirement for issuance of 

a permit is that the activity must not be contrary to the public interest, or, if located in OFWs, the 

activity must be clearly in the public interest. Finally, an extremely rigorous nondegradation 

policy covers Outstanding National Resource Waters.r

Integrity of Wetlands Resources

Florida’s rules already contain qualitative and quantitative biological criteria—for example, 

substances shall not be present in concentrations that will result in a dominance of nuisance 

species, and there is a maximum allowable degradation of biological integrity. The state has 

developed procedures for assessing biological communities in streams and lakes, defining 

relevant ecoregions, and identifying relatively pristine reference sites. Florida has also 

developed and implemented the toughest standards for phosphate loading in the country, 10 

ppb, for the Everglades.

Table 25 summarizes the acreage of affected wetlands regulated by FDEP (since 2003) and the 

water management districts (since 2000).

Wetlands Management and Protection

Florida implements an independent permitting program that operates in addition to the federal 

dredge-and-fill permitting program. The state’s regulatory permit program is implemented 

differently, depending on the location of the activity. As described below, this includes a 

statewide regulatory environmental resource and wetland resource permit under Part IV, 

Chapter 373, F.S, and a mangrove trimming and alteration program under Chapter 403, F.S., as 

follows:

• In peninsular Florida (encompassing the geographic territory of four water 

management districts, beginning south and east of mid-Jefferson County):

—An Environmental Resource Permit (ERP) Program regulates virtually 

all alterations to the landscape, including all tidal and freshwater 

wetlands and other surface waters (including isolated wetlands) and 

uplands. The ERP addresses dredging and filling in wetlands and 

 q Wetlands owned entirely by one person other than the state are not considered waters of the state; this would include isolated

wetlands owned entirely by one permit (Section 403.031[13], F.S.). r Although this last designation, created in 1989, applies to Everglades and Biscayne National Parks, it has not been confirmed by 

the Florida legislature.
2008 Integrated Water Quality Assessment for Florida

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Table 25. Acreage of Affected Wetlands Regulated by FDEP (since 2003)

and the Water Management Districts (since 2000)

Agency

Wetlands Acreage

Acreage 

Permanently Lost3 Acreage Created4 Acreage Preserved5 Acreage Improved6

FDEP1 323.9 570.9 62.8 892.1

Water Management Districts

Northwest Florida 124.0 5,205.7 117.2 573.9

Southwest Florida 1,487.3 8,648.2 2,233.7 3,209.6

St. Johns River 6,394.7 57,381.5 1,339.4 9,033.4

South Florida 16,538.5 38,847.9 10,875.4 19,723.9

Suwannee River 24,594.4 110,621.3 14,635.8 34,133.9

Totals2 49,462.8 221,275.4 29,264.3 67,567.0

1 FDEP data coverage is from February 2003 to the present. This marks the creation of the ERPce Database for tracking wetlands 

impacts. Previous data reported have proven to be unreliable. 2 Data do not represent impacts from nonregulated or unpermitted activities. 3 Wetlands that have been destroyed. 4 Wetlands created where none existed (i.e., in uplands). 5 Wetlands having additional protective devices placed on them (i.e., conservation easements). 6 Poor or lesser quality jurisdictional wetlands that have been enhanced through various activities (i.e., improved hydrology; the 

removal of exotics, the re-establishment of native flora).

other surface waters, as well as stormwater runoff quality (i.e., stormwater 

treatment) and quantity (i.e., stormwater attenuation and flooding of other 

properties), including that resulting from alterations of uplands. The program 

regulates everything from the construction of single-family residences in 

wetlands, convenience stores in uplands, to dredging and filling for any 

purpose in wetlands and other surface waters (including maintenance 

dredging), to the construction of roads located in uplands and wetlands, to

agricultural alterations that impede or divert the flow of surface waters. 

Issuance of the ERP also constitutes a water quality certification or waiver 

under Section 401 of the CWA, 33 U.S.C. 1341. In addition, the issuance of 

an ERP in coastal counties constitutes a finding of consistency under the

Florida Coastal Zone Management Program under Section 307 (Coastal Zone 

Management Act). The ERP Program is implemented jointly by FDEP and four 

water management districts, in accordance with an operating agreement that 

identifies the respective division of responsibilities.

• In the Panhandle (encompassing the geographic territory of the Northwest 

Florida Water Management District, west of and including mid-Jefferson 

County):

—A Wetland Resource Permit Program under Rule 62-312, F.A.C, regulates 

dredging and filling in all tidal and freshwater wetlands and other surface 

waters that are connected (by one or more natural or artificial waters) to other 

bays, bayous, streams, rivers, lakes, estuaries, or the Gulf of Mexico. It does 

not regulate dredging or filling in isolated wetlands. The issuance of a Wetland 

Resource Permit also constitutes a water quality certification or waiver under 
2008 Integrated Water Quality Assessment for Florida

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Section 401 of the CWA, 33 U.S.C. 1341, and a finding of consistency under 

the Florida Coastal Zone Management Program under Section 307 (Coastal 

Zone Management Act). This program is implemented solely by FDEP.

—A separate stormwater permit program under Rule 62-25, F.A.C., regulates 

construction and land alterations (typically in uplands) that collect, convey, 

channel, hold, inhibit, or divert the movement of stormwater and that discharge 

into surface waters. The program only addresses the quality of water 

discharged from stormwater systems, not the quantity of water (i.e., it does not 

address flooding issues, as does the ERP Program in the rest of the state.) 

This program is implemented solely by FDEP, except that the city of 

Tallahassee has received a delegation to review and take agency action on 

stormwater general permits within its geographic limits (see below).

—An agricultural and dam safety program implemented by the Northwest Florida 

Water Management District under Rule 40A-4, F.A.C. This includes regulating 

the management, storage, and drainage of surface waters associated with 

agricultural and forestry projects. The program has jurisdiction over impacts to 

isolated wetlands in agricultural lands, and issuance of this permit constitutes 

water quality certification under Section 401 of the CWA, 33 U.S.C. 1341. The 

dam safety program regulates the construction, alteration, or abandonment of 

dams or levees utilized in nonagricultural settings.

In addition to the regulatory permit programs described above, activities that are located on 

submerged lands owned by the state (otherwise called sovereign submerged lands) also require 

a proprietary authorization for such use under Chapter 253, F.S. Such lands generally extend 

waterward from the mean high water line (of tidal waters) or the ordinary high water line (of 

fresh waters) both inland and out to the state’s territorial limit (approximately 3 miles into the 

Atlantic Ocean, and 10 miles into the Gulf of Mexico). If such lands are located within certain 

designated Aquatic Preserves, the authorization also must meet the requirements of Chapter 

25, F.S. Such authorization considers issues such as riparian rights, impacts to submerged 

land resources, and the preemption of other uses of the water by the public. Authorizations 

typically are in the form of consents of use, easements, and leases. This program is 

implemented jointly by FDEP and four of the state’s five water management districts, in 

accordance with the same operating agreement that governs the ERP Program. The program 

is structured so that applicants who do not qualify at the time of the permit application for both 

the regulatory permit and the proprietary authorization cannot receive either a permit or 

authorization.

Although each FDEP and water management district office has its own enforcement officers, the 

public reports many violations. Public education occurs through several state pamphlets and 

documents, technical and regulatory workshops, and newspaper coverage. The press has 

done a good job of reporting on wetlands issues.

As discussed above, Florida uses its own methodology (Rule 62-340, F.A.C.), rather than the 

federal methodology, to define the boundaries of wetlands and other surface waters. This 

approach, designed specifically for Florida wetlands communities, determines the landward 
2008 Integrated Water Quality Assessment for Florida

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extent of wetlands and other surface waters. It applies to both isolated and contiguous 

wetlands, with some exceptions in northwest Florida, and must be used by all local, state, and 

regional governments.

Numerous programs are working to restore both freshwater and estuarine wetlands—most 

notably the Everglades system. Over 60,000 acres of filtration marshes, known as stormwater 

treatment areas, are being built to reduce the phosphorus in agricultural runoff entering the 

Everglades.

Comprehensive mapping is essential to assessing the extent of Florida’s wetlands and how 

human activities affect them. Both the U. S. Fish and Wildlife Service and the FWCC have 

mapped wetlands in Tampa Bay, and Sarasota Bay. In addition, FDEP continues to develop its 

GIS capabilities to track the wetlands management program.

Land acquisition is crucial to wetlands preservation. The state has bought wetlands and other 

environmentally sensitive lands since 1963, mainly through the Florida Forever and 

Conservation and Recreation Lands (CARL) Programs, administered by FDEP, and the Save 

Our Rivers (SOR) Program, administered by the water management districts. Both are funded 

primarily by the documentary stamp tax on the transfer of property. Additional funding comes 

from the Preservation 2000 (P-2000) Trust Fund. In addition to outright land purchases, the 

state and water management districts can enter into agreements where the owner retains use of 

the property with certain restrictions such as conservation easements, the purchase of 

development rights, leasebacks, and sale with reserved life estates.

Florida’s five water management districts regulate agriculture and silviculture under Chapter 

373, F.S. Permit applicants must show that they will not harm wetlands (including isolated 

wetlands) of five acres or larger. FDACS also has developed and advises the districts on 

agricultural and silvicultural BMPs in hardwood forested wetlands. In addition, the districts 

administer permits for surface water and ground water withdrawals (consumptive use 

permitting) under Part II, Chapter 373, F.S.

Mitigation, which is often used to offset otherwise unpermittable wetlands impacts, may include 

the restoration, enhancement, creation, or preservation of wetlands, other surface waters, or 

uplands. Prior to 2004, the recommended ranges of ratios for offsetting wetland impacts 

through mitigation generally ranged from 1.5:1 to 4:1 for created or restored marshes, 2:1 to 5:1 

for created or restored swamps, 4:1 to 20:1 for wetlands enhancement, 10:1 to 60:1 for 

wetlands preservation, and 3:1 to 20:1 for uplands preservation.

In 2004, FDEP, in consultation with the water management districts, adopted a statewide 

Uniform Mitigation Assessment Method (UMAM) in Rule 62-345, F.A.C. All state, regional, and 

local agencies in the state use UMAM to determine the amount of mitigation required to offset 

impacts to wetlands and other surface waters. As of August 2005, the U. S. Army Corps of 

Engineers, Jacksonville District, also began using this method. It is used to determine the 

amount of functional loss caused by a proposed project, and the amount of “lift” need to offset 

that loss of function. 

FDEP and the water management districts adopted rules governing mitigation banks in 1994 

(Rule 62-342, F.A.C.). A mitigation bank is a large area set aside for enhancement, restoration,

and preservation. Mitigation credits are the increase in ecological value from restoring, creating, 

enhancing, or preserving wetlands. Permit applicants can use mitigation credits to offset 
2008 Integrated Water Quality Assessment for Florida

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damage to wetlands functions. Table 26 lists all mitigation banks in the state and the agency 

administering each of them.

Table 26. Mitigation Banks in Florida

Bank Name Administrative 

Agency* Acres Potential Credits

Credits 

Released

Credits 

Used

Bear Point FDEP 317.00 49.80 20.00 0.10

Breakfast Point FDEP 4,637.00 1,051.66

Corkscrew FDEP 635.00 351.80

Devils Swamp FDEP 3,049.20 526.80

FMB FDEP 1,582.00 847.50 847.50 646.60

FPL/EMB I FDEP 4,124.67 424.50 382.00 219.22

FPL/EMB II FDEP 9,026.00 1,769.53 194.60 27.90

Garcon FDEP 337.00 172.39 77.40 2.90

Graham FDEP 65.90 32.50 29.25 5.50

Lox FDEP 1,264.00 641.60 299.40 194.90

LPI FDEP 1,264.00 807.00 279.40 119.60

San Pedro FDEP 6,748.00 1,083.00 48.80 0.00

Sand Hill Lakes FDEP 2,155.00 298.40

Wekiva River FDEP 1,643.00 390.12 48.80 4.10

Big Cypress SFWMD 1,280.00 1,001.78 593.50 197.00

Bluefield SFWMD 2,675.00 1,240.00 558.14 109.80

Panther SFWMD 2,788.15 934.64 653.06 404.40

Platt’s Creek SFWMD 82.40 69.51

Reedy Creek SFWMD 2,992.98 908.90 407.00 274.88

RG Reserve SFWMD 638.00 32.48 2.55 0.58

Treasure Coast SFWMD 2,545.14 1,033.43

Barberville SJRWMD 365.82 84.30 54.20 30.00

CGW SJRWMD 150.00 63.10 50.50 39.35

Colbert SJRWMD 2,604.00 718.80 268.70 201.80

East Central SJRWMD 1,061.00 286.30 286.30 157.89

Farmton SJRWMD 23,992.00 4,585.00 555.74 247.86

Lake Louisa SJRWMD 1,007.00 297.90 256.30 192.89

Lake Monroe SJRWMD 603.00 199.90 130.00 110.50

Loblolly SJRWMD 6,246.92 2,034.30 508.58 115.26

Longleaf SJRWMD 3,020.70 813.80 105.54 15.60

Mary A SJRWMD 2,068.50 1,252.80 302.90 85.74

NE Florida SJRWMD 779.00 407.30 400.00 376.95

Port Orange SJRWMD 5,719.00 1,176.30 237.90 48.70

Sundew SJRWMD 2,107.10 698.30 81.80 70.63

TM-Econ SJRWMD 5,198.90 1,568.60 350.46 66.20

Toso SJRWMD 1,312.00 185.00 153.10 151.70

Tupelo SJRWMD 1,524.80 459.70 132.20 127.73
2008 Integrated Water Quality Assessment for Florida

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Bank Name Administrative 

Agency* Acres Potential Credits

Credits 

Released

Credits 

Used

Boran SWFWMD 236.76 108.59 70.24 32.10

Clear Springs SWFWMD 1,168.00 438.00

Myakka SWFWMD 380.00 224.60

Tampa Bay SWFWMD 161.23 111.55

The following banks have released all available credits and are closed:

Wetlandsbank SFWMD 420.00 370.00 367.37 367.37

Split Oak SFWMD 1,049.00 206.50 88.80 88.80

* SFWMD – South Florida Water Management District.

 SJRWMD – St. Johns River Water Management District.

 SWFWMD – Southwest Florida Water Management District.
2008 Integrated Water Quality Assessment for Florida

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CHAPTER 4: GROUND WATER 

MONITORING AND ASSESSMENT 

Summary of Ground Water Monitoring Programs 

The quality of ground water is of foremost concern in Florida, because ground water is so 

heavily used as a potable water source and because ground water inputs into surface water 

systems are so important. Over the years, ground water quality monitoring has been 

incorporated into several programs. The programs pertinent to this report are discussed below 

and summarized in Table 277.

Table 27. Summary of Ground Water Monitoring Programs and Data Sources

Monitoring Network or Program Period Description

FDEP-maintained Monitoring Networks

Status Network 1999–

ongoing

Statewide probabilistic sampling network of over 1,100 water 

wells per cycle. Probabilistic sampling occurs over the 5-year 

basin rotation schedule. Sample locations are randomly 

selected from a list frame of wells with samples collected from 

30 wells from unconfined and 30 confined aquifers in a given 

basin. Data to characterize water quality on a basinwide scale, 

and parameters monitored correspond with those targeted in 

surface water evaluations.

Background Network and Temporal 

Variability (TV) Subnetwork 1985–99

Statewide network of 1,600 water wells and monitoring wells to 

spatially monitor general background water quality of local 

aquifers (surficial, intermediate, and Floridan). On average, 

each well was sampled once every 3 years for an extensive list 

of analytes. TV network wells sampled monthly to quarterly.

Ground Water Temporal Variability 

(GWTV) Subnetwork

1999–

ongoing

Current temporal network consists of 46 wells statewide. 

Designed to help correlate Status Network results with seasonal 

hydrologic variations, estimate temporal variance of analytes.

Very Intense Study Area (VISA) 

Network 1989–99

Network monitored the effects of land uses on ground water 

quality in 23 selected areas of the state. Individual VISAs 

consisted of approximately 20 wells sampled 3 times over an 

11-year period. Sampled for a targeted list of analytes.

Springs Monitoring Network 2001–

present

58 samples collected quarterly from 23 first-magnitude and 9 

second-magnitude spring clusters. Basic analyte list identical to 

that used for the Status Network.

Programs That Include Potable Ground Water Sampling 

Public Water System (PWS) 

Monitoring

1975–

Ongoing

Under Rule 62-550, F.A.C., all public water systems are 

required to monitor and report water quality at regular intervals 

within their Compliance Cycle. Ground water is the primary 

source of potable water in the state. 

FDOH/FDEP Water Supply 

Restoration Program (WSRP)–

Private Well Sampling Program

Ongoing

Private well data collected in investigations of potential ground 

water contamination, maintained in an FDEP WSRP database. 

Parameter list is variable, depending on contaminants of 

concern.

Monitoring of discharges 

to ground water Ongoing

Under Rule 62-522, F.A.C., facilities discharging to ground 

water are required to implement a ground water monitoring plan 

and report those results to FDEP.
2008 Integrated Water Quality Assessment for Florida

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FDEP-maintained Ground Water and Springs Monitoring

Programs

FDEP established a ground water quality monitoring network in 1984, under the authority and 

direction of the 1983 Water Quality Assurance Act. From 1984 to1999, the Background 

Network was maintained to establish the background and baseline ground water quality of major 

aquifer systems in Florida. In 1999, FDEP initiated a probabilistic sampling Status Network to 

assess ground water and surface water quality on a basinwide scale. This sampling has been 

integrated into the agency’s watershed management approach. Thus the ground water 

assessment has been conducted using the 29 surface water basins discussed in Chapter 2. 

The first round of sampling was initiated in 2000, and over 1,100 wells are evaluated in each 

basin management cycle.

Monitoring results for the Ground Water Temporal Variability Network, which also began in 

1999, are used to assess seasonal and long-term variability in ground water quality. Other, 

historical monitoring efforts include the Background Network, the VISA Network, and FDOH’s 

Private Water Well Quality Survey.

This report used the Status Network monitoring data to evaluate overall ground water quality, 

potential contaminants of concern, and ground water parameters of particular concern that may 

influence receiving surface waters.

FDEP established a springs monitoring network as part of the Florida Springs Initiative. 

Beginning in 2000, this initially included quarterly monitoring at each of the state’s firstmagnitude springs but has since expanded to include important second-magnitude springs as

well. In this report, Springs Initiative monitoring data are evaluated to identify spring water 

quality trends and issues of concern.

Potable Water Monitoring by FDOH/FDEP Water Supply Restoration 

Program

Contaminated drinking water wells are identified through the sampling efforts of the local county 

public health units, supported by FDEP funding. To optimize resources, wells are sampled in 

areas of known or suspected contamination, such as agricultural areas, areas of known offsite 

contamination near regulated facilities, landfills, or near underground storage tanks. 

The State Underground Petroleum Environmental Response (SUPER) Act program at FDOH 

concentrates its efforts in areas suspected to have petroleum-related contamination and targets 

drinking water wells near known storage tanks for sampling.

The Toxics sampling program looks for contamination related to the use of pesticides and 

fertilizers, and contamination from solvents and metals. The program is a cooperative effort 

between FDOH, the county public health units, and FDEP. FDEP funds the program through a 

contract with FDOH, and FDOH directs the sampling effort by the local public health units.

In this report, the WSRP database maintained by FDEP was used in the evaluation of the 

ground water contaminants of concern identified in private drinking water wells. The database 

currently has water quality records for approximately 44,000 private wells. A caveat to their use 

in this evaluation is that these wells are not evenly distributed because they were sampled in 
2008 Integrated Water Quality Assessment for Florida

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areas of known or suspected contamination. Thus, the number of detections in a particular 

basin can be misleading because results may depend on well density and distribution in 

relationship relative to a given problem area.

Public Water System (PWS) Monitoring

Approximately 5,000 public water systems in Florida rely on ground water. These are served by 

nearly 10,000 wells. Rule 62-550, F.A.C., sets the drinking water standards, monitoring 

requirements, and treatment techniques to be met by public water systems and the testing 

protocol required for certified laboratories. The ultimate concern of the public water system 

supervision program is the quality of water for human consumption when the water reaches 

consumers, and so public water system monitoring involves the direct sampling of wells in some 

instances. However, water quality results also include samples from various entry points into 

the water system, may include treated water, and for some parameters may include composite 

samples.

The monitoring framework for public water systems is a nine-year compliance cycle containing

specific monitoring requirements for individual parameter groups and specific actions based on 

the detection of parameters above action limits or maximum contaminant levels (MCLs). Water 

quality data in the PWS database are reported by system (PWS ID#). While individual sample 

results collected for this report may exceed an action level or MCL, that exceedance does not 

necessarily translate directly into a violation of water delivered to the consumer (1) because of 

the compositing or blending of water mentioned above, or (2) because averaging with 

subsequent samples was below the action level or MCL.

Water quality data in the PWS database were used in the evaluation of regional and statewide 

contaminants of concern. These data can either represent one individual well or a composite 

sample from multiple wells that comprise a system. Generally, the most densely populated 

areas of the state have public supply systems with multiple wells, while less populated areas 

may rely on only one well. Each public supply well was assigned to a basin or, in the case of a 

system, the basin that represents the majority of those wells. In the analysis of contaminants of 

concern, the number of MCL exceedances is not weighted, and thus each exceedance may 

represent one individual well or a composite of many wells in a system. Drinking water 

standards, monitoring requirements, and the frequency of sampling for public water supply wells 

are based on Rule 62-550, F.A.C.

Monitoring of Discharges to Ground Water

FDEP implements a comprehensive ground water quality protection program that regulates 

discharges to ground water. The program establishes ground water quality standards and 

classifications and permitting criteria. Within several FDEP rules there are construction and 

operation requirements, minimum setbacks, and ground water monitoring criteria. 

Most permitted discharges to ground water are required to submit and implement a ground 

water monitoring plan showing the location of the proposed upgradient and downgradient 

monitoring wells, construction details, and a ground water sampling and analysis protocol. At a 

minimum, these plans require three monitoring wells: a background well, an intermediate well, 

and a compliance well. These wells are generally sampled quarterly, and the analysis is 

submitted to FDEP to ensure compliance with Florida’s ground water standards. 
2008 Integrated Water Quality Assessment for Florida

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Summary of Ground Water Quality

Overall Ground Water Quality

Data from the Status Network and GWTV Subnetwork (trends) were used to evaluate the 

overall quality of ground water based on primary ground water MCLs. The data were sorted into 

analyte groups, and an “indicator” analyte was selected to determine ground water quality for 

wells in each of the basins. The groups used in this evaluation include metals, bacteria, 

nitrates, and saline water, which represent some of the the most common threats to drinking 

water noted by the EPA in national surveys. Organics and radionuclides were not included in 

the Status Network parameter list but are addressed in a later section of this chapter.

Most of the wells used in this statewide evaluation of overall ground water quality were selected 

randomly from a database of candidate wells. They are of all types—including private, public, 

monitoring, and, less commonly, agricultural irrigation wells—that represent the basin’s most 

predominant aquifers used for potable supply. These data indicate general basin-scale or 

statewide conditions and do not represent local conditions. They generally represent ambient 

ground water quality, although a small number of upgradient facility wells are included. This is a 

small number of wells and there may be data sufficiency issues for some basins and analytes, 

but it is assumed for the purposes of this analysis that the water quality in these wells provides a 

reasonable representation of overall ground water conditions.

The total basin area sampled for ground water conditions was estimated by assuming that each 

well represented one square mile of the aquifer’s ground water. These data were then added to 

estimate the areal extent (by percent) of the state’s ground waters that are sorted by two major 

categories, unconfined and confined. Florida’s unconfined aquifers exist under water table 

conditions, are directly responsive to precipitation, and are more vulnerable to contaminant 

sources. Confined aquifers are separated from the surface by geologic material (such as clay) 

that retards the downward and upward migration of water ,and thus are considered less 

vulnerable to contamination from the surface. Table 28 presents the results of this evaluation.

In the statewide dataset, bacteria (as total coliform) and salinity (as sodium) were the analyte 

groups with the fewest wells that were found to meet their designated uses. Table G-1 in 

Appendix G provides the ground water MCLs.

Coliform bacteria can commonly reflect conditions in the well rather than the aquifer when 

associated with well construction or inadequate maintenance issues, and so these results 

should also be scrutinized. They are discussed in greater detail in the next section, on 

contaminants of concern. The statewide assessment shows that wells in approximately 

approximately 20% of the ground waters of the state exceeded the MCL for total coliform.
2008 Integrated Water Quality Assessment for Florida

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Table 28. Indicator Analytes and Overall Ground Water Quality in Florida’s Aquifers

Indicator Analyte

Statewide All Aquifers (sampled 2000–07)

Status/Trends Networks

Percent of Ground Water Samples in the State Meeting 

Designated Use in Confined (C) and Unconfined (U) 

Aquifers

Metals, Highest % MCL 97.9%(C); 96.4%(U); as lead1

Metals, Arsenic 99.2%(C); 95.5%(U)

Total Coliform 84.3%(C); 76.8%(U)

Nitrates 100%(C); 98.20%(U)

Saline Water, Sodium 85%(C); 95.50%(U)

Notes:

– The estimates in Table 28 may change as more ground water data become available. 

– Maximum value per well was used to produce a conservative assessment with equal representation from wells. 

– Detection limits for some of the historical data may have been higher than current laboratory method detection limits. 

– All values below the detection limit were consistently used at half the laboratory method detection limit. In some cases, this may 

slightly affect the number of MCL exceedances.

– There are several metals that have primary ground water standards. When all metals were assessed, the value used represents 

the metal with the highest number of samples exceeding its MCL. When there were no MCL exceedances, the primary metal that 

was sampled most frequently was used for calculations.

 

1 For metals, the greatest number of MCL exceedances was for lead. However, lead concentrations can be elevated due to 

well/plumbing materials and quality assurance issues with sampling. 2 For arsenic, the greatest number of MCL exceedances could be due to anthropogenic or natural abundances, or a combination of 

both. 

3

Sodium can be used as an indicator for saline ground water when freshwater aquifers are 

threatened by saltwater intrusion. The issues with salt water can be related to increased ground 

water usage that creates the upconing of mineralized ground water from deeper aquifers or 

seawater intrusion if wells are located in coastal areas. Saline water (as sodium) may be a 

concern in confined-aquifer ground water in approximately 15% of the state, based on statewide 

statistics. However, the number for unconfined aquifers was much lower.

One or more metals exceeding a primary ground water MCL was found to occur in 4.5% of the 

unconfined-aquifer wells, with the most prevalent metals exceedances for lead and arsenic. 

Lead detections are sometimes related to well casing or plumbing material, but arsenic is most 

frequently associated with a contaminant source or natural condition in the aquifer when it is 

found at concentrations above its MCL.

Nitrate is a conservative contaminant, and detected concentrations are not typically biased by 

well materials or sampling technique. Elevated nitrate detections reflect the presence of nutrient 

sources such as fertilizers, animal waste, or domestic wastewater. According to the statewide 

assessment, nitrates above MCLs would be a concern in fewer than 2% of the unconfined wells.

This generalized analysis shows that overall ground water quality in the state is good, when 

considering these parameters. The statewide assessment suggests that over 84% of the 

confined aquifers and over 76% of the unconfined aquifers meet their designated use, with 

coliform bacteria being the most limiting contaminant. Excluding bacteria, 85% of the confined 

and 95% of the unconfined aquifers meet their designated use of providing potable water. 
2008 Integrated Water Quality Assessment for Florida

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However, this analysis indicates that there are some ground water quality issues in the state,

and, depending on the contaminant, they can occur on a localized or regional scale . The 

following section describes the contaminants of concern in Florida and their observed 

occurrence in potable ground waters.

Ground Water Quality Issues and Contaminants of Concern, 

Including Public Health Issues

As discussed in the analysis of ambient data, the overall quality of ground water in Florida is 

good. However, there are ground water quality issues in specific areas. Monitoring networks, 

private well sampling data, and water quality data from public water systems that are served by 

ground water were used to develop a summary of the categories of parameters that were most 

frequently found at levels exceeding MCLs in potable water aquifers. These detections help 

shape some of the issues that pose the most significant concern to potable ground water 

resources. Figure 7 provides a statewide summary of findings by contaminant category. Table 

29 provides summary information on contaminant categories in each of the state’s 29 major 

basins. These categories include volatile organic compounds (VOCs), pesticides/synthetic 

organic chemicals (SOCs), nitrates, primary metals, salinity (as measured by sodium 

concentrations), and radionuclides. The specific contaminants included in this evaluation have 

potable ground water MCLs. Although not included in the summary table, trihalomethanes and 

bacteria are significant contaminants affecting water supplies, and they are also discussed in 

this section.

Volatile Organic Compounds

Volatile organics can be highly mobile and persistent in ground water, and incidences of ground 

water contamination by VOCs are widespread. Table 29 summarizes the numbers of water 

systems or wells with above-MCL detections of VOCs that have primary drinking water MCLs in 

aquifers used for potable supply. The greatest numbers of public water systems with aboveMCL VOC detections were in the Ocklawaha (23 systems), Middle St. Johns (16 systems), and 

Tampa Bay Tributaries (14 systems) Basins. The largest numbers of MCL exceedances in 

private wells were in the Lower St. Johns (184), Tampa Bay Tributaries (158 wells), Sarasota

Bay–Peace–Myakka (158 wells), and Middle St. Johns (139 wells) Basins. The largest number 

of Status Network wells with above-MCL VOC detections occurred in the Lake Worth Lagoon–

Palm Beach Coast and Sarasota Bay–Peace–Myakka Basins(5 wells each).

Benzene was the compound that most frequently exceeded MCLs in each of the three sets of 

water quality data. Trichloroethene (TCE) was the second most frequently detected compound 

above MCLs in the PWS and WSRP datasets, closely followed by tetrachloroethene (PCE, 

which was the second most frequently detected compound in the state monitoring networks). 

Other compounds with primary MCLs that were detected included vinyl chloride, 

dichloromethane, 1,1-dichloroethene, 1,2-dichloroethane, and carbon tetrachloride (in PWS 

systems only). The most frequently repeated detections in public water systems occurred in the 

basins of southeastern Florida, with the primary compounds being vinyl chloride and TCE.
2008 Integrated Water Quality Assessment for Florida

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Figure 7. Statewide Summary of Contaminants of Concern in Potable Ground Water Sources

 

 

 

0 500 1000 1500 2000 2500 3000

Radionuclides

Saline Water

Primary Metals

VOC

Nitrates

Pesticides/SOC

NUMBER OF WATER SYSTEMS OR WELLS WITH MCL EXCEEDENCES

Public Water Systems Private Wells (WSRP) Status/ Background/ VISA Network Wells
2008 Integrated Water Quality Assessment for Florida

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Table 29. Summary of Contaminants of Concern for Aquifers Used as Potable Water Sources

Basin—Aquifer

Contaminant Categories and Number of Wells or Water Systems 

with Samples that Have Exceeded Primary Standards

VOCs1 Pesticides/SOCs2 Nitrates3

Public Water Systems7Private Wells (WSRP) 8Status/ Background/ VISA Network WellsPublic Water Systems7Private Wells (WSRP) 8Status/ Background/ VISA Network WellsPublic Water Systems7Private Wells (WSRP) 8Status/ Background/ VISA Network Wells

Apalachicola–Chipola—Floridan Aquifer 4 17 4 645 0 43

Caloosahatchee—Surficial Aquifer 7 13 1 9 7 1

Charlotte Harbor—Floridan Aquifer (SW) 0 62 2 3 0 2

Choctawhatchee–St. Andrew—Floridan Aquifer 1 36 1 5 19 0 2

Everglades—Surficial Aquifer (SW) 1 3 1 0

Everglades West Coast—Surficial Aquifer 1 5 1 7 0 6

Fisheating Creek—Surficial Aquifer 0 2 1 2 2

Florida Keys—None 0 2 0 0

Indian River Lagoon—Floridan and Surficial Aquifers 6 36 5 3

Kissimmee River—Floridan, Intermediate, and Surficial Aquifers 11 58 3 21 798 2 6 1,154 10

Lake Okeechobee—Surficial Aquifer (SW) 2 6 1 0

Lake Worth Lagoon–Palm Beach Coast—Surficial Aquifer 9 55 5 6 4 1

Lower St. Johns—Floridan Aquifer 7 184 5 19 3 35

Middle St. Johns—Floridan Aquifer 16 139 21 118 16 45 1

Nassau–St. Marys—Floridan Aquifer 4 15 0 1 1

Ochlockonee–St. Marks—Floridan Aquifer 2 21 1 3 1 11 1

Ocklawaha—Floridan Aquifer 23 107 1 54 475 12 466

Pensacola—Sand-and-Gravel Aquifer 9 10 3 6 13 2 2 3

Perdido—Sand-and-Gravel Aquifer 2 2 4 1 0 1 2

Sarasota Bay–Peace–Myakka—Floridan and Surficial Aquifers 9 158 5 33 248 8 401 2

Southeast Coast–Biscayne Bay---Biscayne Aquifer 8 120 1 9 1 6 13 2

Springs Coast—Floridan Aquifer 15 22 2 7 9 1 11 16

St. Lucie–Loxahatchee—Surficial Aquifer 10 135 15 2 2

Suwannee—Floridan Aquifer 5 120 3 2 60 7 145 5

Tampa Bay—Floridan Aquifer 5 66 6 31 6 16

Tampa Bay Tributaries—Floridan Aquifer 14 158 16 19 48 118

Upper East Coast—Floridan Aquifer and Surficial Aquifer 1 8 2 3 5

Upper St. Johns—Floridan Aquifer and Surficial Aquifer 1 8 1 2 0 1

Withlacoochee—Floridan Aquifer 11 27 1 29 69 7 59 1

STATEWIDE SUMMARY—All results 184 1,595 34 272 2,529 17 148 2,537 29

Notes:

1 Systems or wells with samples that exceeded MCLs for volatile organic compounds, excluding trihalomethanes and ethylene dibromide. 2 Systems or wells with samples that exceeded MCLs for pesticides (also known as synthetic organic chemicals, or SOCs). 3 Systems or wells with samples that exceeded MCLs for nitrate or nitrate+nitrite. 4 Systems or wells with samples that exceeded MCLs for primary metals. 5 Systems or wells with samples that exceeded MCL for sodium, an indicator of salinity.

6 Systems or wells with samples that exceeded MCL for radionuclides, measured as radon 226, radon 228, gross Alpha, and/or gross Beta. 7 PWS data not restricted to wells only. Some parameter results may be for other entry points into a system, composite samples, or treated 

water. Data are from systems that that operate their own wells. While individual sample results collected for this report may exceed an action 

level or MCL, that exceedance does not necessarily translate directly into a violation of water delivered to the consumer (1) because of the 

compositing or blending of water mentioned above, or (2) because averaging with subsequent samples was below the action level or MCL. 8 Private well sampling under the WSRP is targeted sampling conducted in areas of suspected contamination, and the parameters analyzed 

are specific to contaminants of concern.
2008 Integrated Water Quality Assessment for Florida

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Table 29 (continued). Ground Water Contaminants of Concern in Aquifers Used as Potable Water 

Sources

Basin—Aquifer

Contaminant Categories and Number of Wells or Water Systems 

with Samples that Have Exceeded Primary Standards

Primary Metals4 Saline Water5 Radionuclides6 Public Water Systems7 Private Wells (WSRP) 8 Status/ Background/ VISA Network Wells Public Water Systems7 Private Wells (WSRP) 8 Status/ Background/ VISA Network Wells Public Water Systems7 Private Wells (WSRP) 8 Status/ Background/ VISA Network Wells

Apalachicola–Chipola—Floridan Aquifer 25 55 8 5

Caloosahatchee—Surficial Aquifer 12 8 1 4 14 1 3

Charlotte Harbor—Floridan Aquifer 10 1 2 5 14 4

Choctawhatchee–St. Andrew—Floridan Aquifer 34 3 3 7

Everglades—Surficial Aquifer 6 2 4

Everglades West Coast—Surficial Aquifer 7 16 7 6 3

Fisheating Creek—Surficial Aquifer 1 1 2 3 2

Florida Keys—None 0 1 0

Indian River Lagoon—Floridan and Surficial Aquifers 20 6 6 3 9 2 9 1

Kissimmee River—Floridan, Intermediate, and Surficial Aquifers 46 2 34 6 4 30 4

Lake Okeechobee—Surficial Aquifer 5 2 1 1 5 3

Lake Worth Lagoon–Palm Beach Coast—Surficial Aquifer 29 5 10 1 1 9

Lower St. Johns—Floridan Aquifer 68 121 19 3 15 6 8 3

Middle St. Johns—Floridan Aquifer 48 8 38 16 15 8 13 3

Nassau–St. Marys—Floridan Aquifer 16 17 4 1 0

Ochlockonee–St. Marks—Floridan Aquifer 19 7 9 1 1 11 1

Ocklawaha—Floridan Aquifer 116 71 26 12 1 1 5 3

Pensacola—Sand-and-Gravel Aquifer 27 18 20 2 18 17

Perdido—Sand-and-Gravel Aquifer 2 1 5 2 6

Sarasota Bay–Peace–Myakka—Floridan and Surficial Aquifers 70 17 35 8 10 3 97

Southeast Coast–Biscayne Bay–Biscayne Aquifer 28 54 83 6 4 7 9 7

Springs Coast—Floridan Aquifer 41 54 16 11 8 6 7

St. Lucie–Loxahatchee—Surficial Aquifer 32 18 13 2 3 4 4 1

Suwannee—Floridan Aquifer 38 76 35 7 3 5 8 19

Tampa Bay—Floridan Aquifer 33 17 6 3 17

Tampa Bay Tributaries—Floridan Aquifer 121 102 11 48 4 10 53 27

Upper East Coast—Floridan Aquifer and Surficial Aquifer 12 4 19 5 2 4

Upper St. Johns—Floridan Aquifer and Surficial Aquifer 6 2 16 7 2 1

Withlacoochee—Floridan Aquifer 78 132 12 7 2 9 13

STATEWIDE SUMMARY—All results 950 792 452 148 82 93 376 28 79

Notes:

1 Systems or wells with samples that exceeded MCLs for volatile organic compounds, excluding trihalomethanes and ethylene dibromide. 2 Systems or wells with samples that exceeded MCLs for pesticides (also known as synthetic organic chemicals). 3 Systems or wells with samples that exceeded MCLs for nitrate or nitrate+nitrite. 4 Systems or wells with samples that exceeded MCLs for primary metals.

5 Systems or wells with samples that exceeded MCL for sodium, an indicator of salinity.

6 Systems or wells with samples that exceeded MCL for radionuclides, measured as radon 226, radon 228, gross Alpha, and/or gross Beta. 7 PWS data not restricted to wells only. Some parameter results may be for other entry points into a system, composite samples, or treated 

water. Data are from systems that that operate their own wells. While individual sample results collected for this report may exceed an action 

level or MCL, that exceedance does not necessarily translate directly into a violation of water delivered to the consumer (1) because of the 

compositing or blending of water mentioned above, or (2) because averaging with subsequent samples was below the action level or MCL. 8 Private well sampling under the WSRP is targeted sampling conducted in areas of suspected contamination, and the parameters analyzed 

are specific to contaminants of concern.
2008 Integrated Water Quality Assessment for Florida

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Synthetic Organic Chemicals/Pesticides

For SOCs used as pesticides, the largest number of MCL exceedances in public water systems 

occurred in the Oklawaha (54 systems).Sarasota Bay–Peace–Myakka (33 systems) and 

Withlacoochee (29 systems) Basins. In private wells, the largest number occurred in the 

Kissimmee (798 wells), Apalachicola (645 wells), and Ocklawaha (475 wells) Basins. The 

detections of agrichemicals in private wells can provide meaningful information on the 

presence/absence of these substances and give an indication of the aquifer’s vulnerability to 

pesticide use. The number of private well exceedances can sometimes be related to the 

density of homesteads (unregulated rural growth versus dense rural residential developments) 

and their proximity to agricultural land uses or lawn/turf care practices. Table 29 shows the 

distribution of MCL exceedances.

The pesticides that occurred in public water systems at above-MCL concentrations were mainly 

detected in the mid- to late-1980s and have since been banned from use. Lindane, toxaphene,

and methoxychlor were the pesticides most commonly detected at above-MCL concentrations in 

the 1980s, but have not appeared in the PWS database at above-MCL levels since the early 

1990s. These compounds, plus heptachlor, endothal, and malathion, were mainly detected in 

the basins where agricultural land uses are or were prevalent. Dieldrin, another older 

compound, was also detected in private drinking water wells.

EDB, a nematocide used heavily in the 1980s on citrus and other croplands, was found to be 

highly mobile and a threat to potable ground water supplies. In response to FDEP’s 

identification of this as an issue, FDOH conducted a comprehensive EDB sampling program in 

areas where it was suspected to have been applied. In 16 basins, this revealed numerous 

private drinking water wells that were contaminated by the compound, prompting the formal 

delineation of ground water contamination areas. EDB was also detected in public water 

systems throughout the state. In the late 1980s, the use of EDB was banned. New detections 

of EDB seldom occur; however, some private drinking water wells continue to yield samples 

with detectable concentrations of EDB decades after its use was discontinued. The most recent 

PWS system detections of EDB above its MCL (in the late 1990s) were reported in the Tampa 

Bay Tributaries Basin of southwest Florida, which includes a significant agricultural area.

More recently, applied pesticides such as bromacil and alachlor were detected at levels 

exceeding their health advisory limits in private drinking water wells. Bromacil has a ground 

water guidance concentration, and alachlor has a primary MCL. Elevated detections of bromacil 

were found (mainly in the 1990s) in the citrus-growing area of central Florida, which includes 

parts of the Kissimmee, Tampa Bay Tributaries, Middle St. Johns, and Ocklawaha Basins. In 

the 1990s, both compounds were found (along with dieldrin) at elevated levels at numerous 

wells in an agricultural area of Jackson County in the Apalachicola–Chipola Basin. FDACS has 

since required modifications to the application of bromacil to prohibit its application from citrus 

areas with vulnerable soils and high leaching potential. Alachlor is now listed as a restricted use 

pesticide.

Nitrates

Nitrates above the MCL of 10 mg/L were detected in 156 public water systems, with the Tampa 

Bay Tributaries Basin having by far the greatest number (45 systems). The largest number of 

private wells with nitrates above the MCL were found in the Kissimmee Basin (1,154 wells), 

followed by the Ocklawaha (466 wells) and Sarasota Bay–Peace–Myakka (401 wells) Basins. 
2008 Integrated Water Quality Assessment for Florida

101

Several status wells also had nitrate above MCLs, with the largest number in the Kissimmee 

Basin (10 wells). These are all summarized in Table 29.

The basins with the highest number of above-MCL detections in water systems and wells 

include large citrus-growing areas or areas where citrus was previously grown on top of 

vulnerable aquifers. The area of the Kissimmee Basin that has the highest number of aboveMCL concentrations of nitrate in private wells is the ridge citrus area along the basin’s western 

edge. In the early 1990s, FDACS began implementation of a BMP program for growers in the 

ridge citrus area to use fertilizers more efficiently and reduce nitrate concentrations in ground 

water. It is hoped that this program will eventually reduce the number of nitrate exceedances in 

wells.

Primary Metals

Metals with primary drinking water MCLs include arsenic, barium, beryllium, cadmium, 

chromium, lead, mercury, nickel, and selenium. Table 29 summarizes the detections of primary 

metals above their MCLs.

Approximately 1,000 public water systems reported one or more primary metals exceeding an 

MCL, which may be misleading since elevated metals in public water systems are often due to 

the materials containing and conveying the water rather than actual concentrations in the 

ground water. Metal well casings, piping, storage tanks, and plumbing fixtures, in addition to 

sampling techniques, often cause bias in the analysis of ground water samples for metals. Lead 

and cadmium are the most frequently detected metals at above-MCL concentrations in public 

water systems, and both metals are very frequently associated with impurities in water 

distribution and storage systems. Galvanized coatings on metal surfaces, paint, and lead solder 

are documented sources of metals contamination in water systems. The Tampa Bay Tributaries 

(121 systems) and Ocklawaha (116 systems) Basins have the greatest number of water 

systems with above-MCL detections, primarily for lead and cadmium. Results from resampling 

frequently show that the ground water is actually not affected by these metals.

In private drinking water wells, the metals most frequently exceeding MCLs are arsenic and 

lead. The basins with the greatest number of exceedances are the Withlacoochee (132 wells), 

Lower St. Johns (121 wells), and Tampa Bay Tributaries (102 wells) Basins. Lead, again, may 

be an artifact of well materials, piping, or plumbing fixtures, but arsenic is not typically 

associated with any of these. The resampling of private water wells usually reveals that there is 

no actual ground water problem with lead. The majority of the wells in FDEP’s 

Status/Background/VISA Networks that exceed MCLs for metals exceed the MCL for lead, 

followed by arsenic, with a smaller number exceeding the MCL for cadmium. Many of the 

reported concentrations for metals in FDEP’s Status Network are qualified due to the potential 

influence of well materials, lead water level recorder weights, and/or sampling problems.

Future monitoring will help FDEP determine the extent to which elevated metals detections 

actually represent ground water quality. However, for public water systems and private wells, 

the materials composing the water storage and distribution systems, piping, and fixtures will 

continue to pose a challenge to the interpretation of data for metals. Differentiating natural 

sources from contaminating influences is another issue. Arsenic, in particular, can on occasion 

exceed its MCL of 10 μg/L due to natural conditions. 
2008 Integrated Water Quality Assessment for Florida

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Radionuclides

In Florida, most elevated radionuclide levels are due to natural conditions, but these conditions 

may still pose a significant health concern. Radionuclides occur naturally as trace elements in 

rocks and soils as a consequence of the radioactive decay of uranium-238 (U-238) and thorium232 (Th-232). Elevated radionuclide levels occur most commonly from phosphate that is

prevalent in Miocene-age clay deposits present throughout much of the state. Radionuclides 

measured in ground water include gross Alpha, gross Beta, radium 226, and radium 228. Gross 

Alpha is the most commonly measured parameter. Table 29 summarizes radionuclide 

detections in public water systems and wells.

Public water systems in the west-central area of the state have the greatest incidence of MCL 

exceedances for radionuclides. The Sarasota Bay–Peace–Myakka (97 systems) Basin, 

followed by the Tampa Bay Tributaries (53 systems), and the Kissimmee River (30 systems) 

Basins lie within one of the 3 largest phosphate-mining areas in the world; this area includes 

large areas of Manatee, Sarasota, Polk, and Hillsborough Counties. The health department 

infrequently samples private wells for radionuclides. The highest number of detections above 

MCLs was found in the Tampa Bay Tributaries Basin (27 wells).

The Suwannee (19 wells) and Pensacola (17 wells) Basins had the greatest number of 

radionuclide exceedances, although few private wells have been sampled for this parameter 

category.

Saline Water 

The intrusion of saline water is a well-documented concern in coastal areas of the state where a

wedge of salt water migrates laterally inshore as discharge from supply wells increases. 

However, recent data indicate that these are not currently the areas with the greatest number of 

issues. In other areas that lie more inland, the upconing of brackish water from deeper zones 

seems to be more of an issue. In this assessment, an exceedance of the MCL for sodium was 

used as an indicator of possible saline water intrusion or upwelling. Table 29 summarizes these 

results.

Elevated sodium concentrations were noted in samples from public water systems in the Tampa 

Bay Tributaries (48 systems), Middle St. Johns (16 systems), and Ocklawaha (12 systems) 

Basins. Public drinking water supplies in the 3 basins with highest number of sodium 

exceedances are in high-growth areas of the state where consumptive use is beginning to 

exceed aquifer capacity. In these basins, overpumpage has resulted in upconing from deeper 

zones in the Floridan aquifer that are saline. The increase in population in many of these areas 

is creating stress on potable ground water supplies, and water resource managers and public 

water utilities have begun to look for alternative supplies to continue providing potable water to 

their customers. Private wells in the Lower St. Johns (15 wells), Middle St. Johns (15 wells), 

and Sarasota Bay–Peace–Myakka (10 wells) Basins have also been affected by increases in 

aquifer salinity.

Trihalomethanes

Chlorination is a disinfection treatment practiced by many public water systems to remove 

potentially harmful bacteria. Unlike a number of states, Florida requires disinfection. 

Trihalomethanes (THMs) are an unfortunate byproduct of chlorinating source water that 

contains organic matter. Chloroform, dibromochloromethane, bromodichloromethane, and 
2008 Integrated Water Quality Assessment for Florida

103

bromoform are the most common THMs found in treated water. Basins with the most apparent 

influence by THMs (based on primary MCL exceedances) include Middle St. Johns (20 

systems), Lake Worth Lagoon–Palm Beach Coast (19 systems), Everglades West Coast (11 

systems), and Upper East Coast (11 systems). Many public water systems are using alternative 

disinfection methods (such as the use of chloramine) to reduce or eliminate the creation of 

THMs.

Bacteria (Coliform)

Bacteria are not typically a concern to public water systems, because the water is disinfected 

before distribution. However, the bacterial contamination of private wells is an ongoing issue 

that is being addressed by FDOH. Unfortunately, the number of bacterial exceedances in 

private drinking water wells is poorly documented and not maintained in a central database. Of 

all water quality issues evaluated, bacterial contamination, as indicated by elevated total and/or 

fecal coliform counts, is the most prevalent issue in ground water samples collected from the 

Status Network monitoring wells. Over one-third of the basins had significant exceedances of 

MCLs or health advisory levels for total and/or fecal coliform, indicating potential public health 

issues in some of these cases. 

However, the significance of these findings must still be determined. High bacterial counts may 

be caused by improper well construction, poor hygiene at the wellhead, animal waste or septic 

tank issues and/or flooding, and the surface water infiltration of a water system. These 

considerations highlight the fact that individual well assessments are necessary, and that in 

many cases, bacterial contamination is localized and may not be an issue outside of the 

individual wells themselves.

Summary of Ground Water Contaminant Sources 

The EPA’s 2004 Florida Source Water Assessment identified the top five potential sources of 

contamination in Florida. These are (1) underground storage tanks (not leaking); (2) gasoline 

service stations (including historical gas stations); (3) municipal sanitary waste treatment and 

disposal (commercial, domestic, and industrial waste); (4) known contamination sites/plumes 

(equivalent to FDEP’s delineated areas); and (5) drycleaning facilities. Several of these have 

commonly been the focus of waste cleanup and monitoring activities in Florida. However, there 

are also instances where ground water has been degraded as the result of nonpoint activities. 

This section discusses the most significant ground water degradation sources, based on waste 

cleanup, monitoring, and restoration actions taken by FDEP and other agencies concerned with 

ground water quality.

Petroleum Facilities

FDEP’s Storage Tank Contamination Monitoring (STCM) database contains information on all 

storage tank facilities registered with FDEP and tracked for active storage tanks, storage tank

history, or petroleum cleanup activity. Currently, the STCM database lists approximately 61,000 

registered petroleum storage tanks, and it shows that approximately 14,000 storage tank 

facilities have documented ground water contamination by petroleum constituents. Petroleum 

sites and petroleum problems are concentrated in the most populated areas of the state, as well 

as along major transportation corridors. The main petroleum constituents found in ground water 
2008 Integrated Water Quality Assessment for Florida

104

are benzene, toluene, ethylbenzene, xylenes, and methyl tert-butyl ether. Contaminants at 

older petroleum sites may also contain lead and EDB.

Florida’s Petroleum Cleanup Program encompasses the technical oversight, management, and 

administrative activities necessary to prioritize, assess, and clean up sites contaminated by the 

discharges of petroleum and petroleum products from stationary petroleum storage systems. 

These sites include those determined to be eligible for state-funded cleanup using preapproval 

contractors designated by the property owner or responsible party and state lead contractors 

under direct contract with FDEP, as well as nonprogram or voluntary cleanup sites funded by 

responsible parties.

Drycleaning Solvent Facilities

Approximately 1,400 drycleaning facilities (mainly retail) have signed up for eligibility for 

contaminant cleanup under FDEP’s Drycleaning Solvent Cleanup Program (DSCP) due to 

evidence of contamination. Of those, approximately 200 are actively being assessed and may 

be under remedial action. Drycleaning solvent constituents (PCE, TCE, dichloroethenes, and 

vinyl chloride) are among the most mobile and persistent contaminants in the environment.

The Florida legislature has established a state-funded program, administered by FDEP, to clean

up properties that are contaminated as a result of the operations of a drycleaning facility or 

wholesale supply facility (Chapter 376, F.S.). The drycleaning industry sponsored the statute to 

address environmental, economic, and liability issues resulting from drycleaning solvent 

contamination. The program limits the liability of the owner, operator, and real property owner 

of drycleaning or wholesale supply facilities for cleaning up drycleaning solvent contamination, if 

the parties meet the eligibility conditions stated in the law.

Federal and State Waste Cleanup and Monitoring Sites

The Federal Superfund Program (authorized under the Comprehensive Environmental 

Response Compensation and Liability Act [CERCLA]) and Florida’s Hazardous Waste Site 

Cleanup Program were developed to provide mechanisms for addressing contamination on 

uncontrolled or abandoned hazardous waste sites. In the state, there are currently 50

Superfund sites on the National Priorities List (NPL) and 72 sites on Florida’s Hazardous Waste 

Cleanup Program list. Many of these sites have documented ground water contamination.

Nonpoint Sources

Degraded ground water quality is sometimes not associated with a single contaminant source 

but instead may be related to multiple sources or land use practices in an area. In many cases, 

the cumulative effect of human activities through leaching from nonpoint sources of pollution,

such as septic tanks or fertilizer applications, creates ground water quality problems. In many 

urban areas of the state, ground water (including sinkholes and permitted injection wells) 

receives untreated stormwater runoff from urban areas and roadways. Ground water is 

particularly vulnerable in areas of karst, where these discharges have a direct, unfiltered 

pathway to the drinking water resource. In other areas, wastewater applications, septic tank 

leachate, right-of-way maintenance, and residential landscaping fertilization activities can 

degrade ground water quality and cause potential problems in karst areas where springs 
2008 Integrated Water Quality Assessment for Florida

105

discharge. Additionally, the leaching of fertilizers and pesticides from agricultural lands has had 

a significant impact on ground water quality. 

Unfortunately, the potable ground water resource in some areas dominated by agricultural 

activities is often susceptible to direct impacts by fertilizer and agrichemical use. The ridge 

citrus area in central Florida provides an example of an area with known nitrate impacts to 

ground water. The citrus growers in this area are now addressing nonpoint impacts through the 

Agricultural Nonpoint Source Program, using voluntary fertilizer management practices as a 

primary BMP. This work is serving as a model for the implementation of BMPs to protect

ground water from contamination caused by the use of fertilizers and pesticides on urban lands. 

These more-refined BMP programs should reduce the nutrient contamination of ground water.

Ground Water–Surface Water Interaction

Setting and Pathways

The free exchange between ground water and surface water in Florida cannot be 

overemphasized. As mentioned previously, spring-fed stream systems can depend almost 

entirely on ground water discharge. Canals can also contain mostly ground water. Other 

streams and lakes may receive over half of their total inflows via ground water seepage, and 

natural estuaries rely on ground water seepage as a significant source of fresh water. In areas 

where the Floridan aquifer system is near the surface, and in southern parts of the state where 

porous limestone exists near the surface, conduit systems in the limestone material efficiently 

deliver ground water to streams and canals at high rates. In other areas of the state, ground 

water discharge occurs as seepage from the surficial aquifer system.

Ground Water Parameters of Concern for Impaired Surface Waters

Nutrients, DO, and iron are the parameters of greatest concern identified in basin-scale 

evaluations of ground water influence on impaired or potentially impaired surface waters. Table 

30 summarizes the median concentrations of these parameters in unconfined aquifers of the 

state’s 29 major basins. The table also compares these ground water medians with the 

statewide medians for surface water types.

Relatively low concentrations of nitrate and phosphorus can create nutrient imbalances in 

surface water and contribute to impairments. Nitrate in ground water is associated with 

anthropogenic sources such as atmospheric deposition, fertilizers, animal waste, and human 

wastewater. Elevated nitrogen concentrations are of particular concern to fragile surface water 

systems such as spring runs. As discussed previously, phosphorus occurs naturally throughout 

the state, and its natural occurrence in ground water is attributed to ground water contact with 

mineral phosphate in the aquifer material. It can also be derived from organic material such as 

peat or from phosphatic shell beds. The more common anthropogenic sources of phosphorus 

include fertilizers, animal waste, and domestic wastewater/residuals.
2008 Integrated Water Quality Assessment for Florida

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Table 30. Median Concentrations of Ground Water–Surface Water Constituents

in Unconfined Aquifers (2000–07)

Basin

Median Concentrations in Unconfined Aquifers 1, 3

Nitrite+Nitrate 

(mg/L)

Phosphorus 

(mg/L)

DO 

(mg/L)

Total Iron 

(μg/L )

Cycle 1

Dissolved

Cycle 2

Total

Cycle 1

Dissolved

Cycle 2

Total 2000–07 2003–07

Apalachicola–Chipola 0.23 2.35 0.005 0.0135 5.725 20.5

Caloosahatchee 0.002 0.0055 0.0495 0.0425 0.535 1,140

Charlotte Harbor 0.002 0.01 0.031 0.0485 0.58 900.5

Choctawhatchee–St. Andrew 

Bay 0.645 0.16 0.0065 0.008 4.065 67.5

Everglades 0.002 N/A 0.021 N/A 0.235 N/A

Everglades West Coast 0.002 0.0065 0.018 0.047 0.32 819

Fisheating Creek 0.005 0.007 0.035 0.0275 0.51 158

Florida Keys 0.017 N/A 0.037 N/A 0.19 N/A

Indian River Lagoon 0.009 0.007 0.35 0.86 0.755 1100

Kissimmee River 0.01 0.0375 0.86 0.0435 0.87 372

Lake Okeechobee 0.002 0.002 0.4525 0.26 0.295 569

Lake Worth Lagoon– 0.007 0.057 0.23 207

Palm Beach Coast 0.002 0.0515

Lower St. Johns 0.002 0.009 0.044 0.047 0.59 317

Middle St. Johns 0.013 0.02 0.045 0.04 1.24 793

Nassau–St. Marys 0.006 0.007 0.027 0.065 0.82 396

Ochlockonee–St. Marks 0.0305 0.086 0.017 0.024 2.81 197.5

Ocklawaha 0.66 0.27 0.051 0.1 3.6 382

Pensacola 0.28 0.445 0.002 0.002 7.46 54

Perdido 0.825 N/A 0.0035 N/A 5.15 N/A

Sarasota Bay–Peace–Myakka 0.01 0.009 0.12 0.26 1.14 1,510

Southeast Coast–Biscayne Bay 0.0205 0.0085 0.025 0.008 2.92 528

Springs Coast 0.0125 N/A 0.0285 N/A 0.4 N/A

St. Lucie–Loxahatchee 0.0095 0.01 0.0385 0.096 0.17 934

Suwannee 0.03 0.015 0.045 0.058 1.18 429

Tampa Bay 0.01 0.0095 0.04 0.0395 0.54 512

Tampa Bay Tributaries 0.016 0.018 0.057 0.088 1.01 962

Upper East Coast 0.006 5.5 0.205 1.1 0.32 55

Upper St. Johns 0.002 0.002 0.0685 0.25 0.8 805.5

Withlacoochee 0.081 0.02 0.053 0.056 0.73 1,210

Ground Water Statewide Median 0.01 0.01 0.035 0.0425 0.815 454

Statewide Medians for Surface Water2

Lake 0.02 0.03 7.66 158

Stream 0.07 0.08 5.53 200

Estuary 0.01 0.02 7.2 N/A

Notes:

N/A – Not available.

1 Values highlighted in gray exceed medians for at least one waterbody type; values highlighted in yellow exceed medians for all 

surface water types.

2 Obtained from Typical Water Quality Values for Florida’s Lakes, Streams, and Estuaries (Draft), May 2004. Nitrate+nitrite and 

phosphorus threshold values for surface waters are based on total rather than dissolved concentrations.

3 Data used for this assessment were sampled between 2000 and 2007 and mainly include the Status and Trend Network's Cycle 1 

(2000–04) and Cycle 2 (2004–07) basin monitoring. The analytes and list frame of wells used by the Status Network's probabilistic 

design differed for the cycles. The Cycle 1 well list frame included a relatively larger population of background wells, while the Cycle 

2 well list frame included a significantly greater number of upgradient facility wells. DO was sampled during both cycles and total 

iron was only sampled during Cycle 2 of the Status Network.
2008 Integrated Water Quality Assessment for Florida

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Low DO is a normal characteristic of ground water. Depressed DO in springs, spring runs, 

spring-fed rivers, and many drainage canals is primarily or entirely attributable to ground water 

inflows. In instances where ground water contributions to surface waterbodies are high, low DO 

is a typical consequence.

Iron is another ground water constituent that occurs naturally due to the leaching of ferric iron 

from iron-rich clay soils and sediment. Iron in the environment also has an affinity for organic 

materials. Streams that are high in iron concentration typically have a high to moderate ground 

water component, low DO, and high dissolved organic carbon content. 

Springs and Spring-related Issues 

Elevated nitrates are a common and growing problem in Florida springs, with steady rises in 

nitrate levels observed in many Florida springs over the past 30 years (Florida Springs Task 

Force, 2000). Nitrate was once a very minor constituent of Florida spring water. Typical nitrate 

concentrations were less than 0.2 mg/L. Today many Florida springs discharge water that has 

more than 1.0 mg/L of nitrate nitrogen. It is believed that nitrate nitrogen levels as low as 

1 mg/L or less can cause a significant shift in the balance of spring ecological communities, 

leading to the degradation of biological systems due to the overgrowth of algae and sometimes 

aquatic plants.

There is currently no statewide adverse-effects threshold for nitrate for Florida, although several 

science-based values have been offered that can be used for reference purposes. In an FDEPfunded study, Michigan State University researchers determined that algal species reductions 

occurred at nitrate concentrations below 0.591 mg/L for the algal genus Vaucheria spp. and 

below 0.250 mg/L for the more prevalent Lyngbya wollei (Stevenson et al., 2007). Another 

reference threshold was provided in documentation supporting spring run–related TMDLs for 

the Wekiva River and Rock Springs Run by FDEP (Gao, 2007). The Wekiva River/Rock 

Springs Run TMDL was based on a nitrate threshold of 0.286 mg/L, established at a level that 

would reduce overall periphyton biomass concentration to an acceptable level.

For this evaluation, FDEP used spring water quality data provided by the Springs Initiative

special projects and quarterly monitoring network (2000–06). Table 31 lists these reference 

springs, along with median values for nitrate. A reference spring in this report is defined as 

having a nitrate median concentration less than 0.06 mg/L. Some of the springs listed in Table 

31 have limited data and require additional sampling in the future to confirm their inclusion in the 

list of reference springs.

The statewide spring data were combined and compared with the reference springs for 

nutrients. The period of record for statewide nitrate nitrogen data is 1985 to 2007; however, 

most springs only have data from 2000 to 2006. The statewide median nitrate value was over 

50 times higher than the median value for reference springs. The first-magnitude springs were 

also compared with the reference springs and have a similar result. 

The trends in water quality for springs are best analyzed by looking at the data for individual 

springs or groups of springs that are in close proximity and comparing them with reference 

springs (Figure 8). Some springs were organized by clusters or groups to increase the number 

of sampling events. For the empirical trend analysis in this report, only the data from the 2000 

to 2006 period of monitoring implemented by the Springs Initiative were used. There could be 
2008 Integrated Water Quality Assessment for Florida

108

several contributing factors to observable trends, but the overall increases in nitrate are 

associated with anthropogenic sources. Essentially no nitrate trends were identified in the 

reference springs, where the primary source of nitrate is assumed to be atmospheric deposition. 

Nitrate trends for most other springs, especially those springs with the highest nitrate 

concentrations in the state, show measurable increases.

Nitrate concentrations in spring clusters or springs that had at least 10 observations over at 

least four years were plotted over time to observe trends. The spring clusters or springs were 

categorized by the magnitude of the nitrate impact into five groups. Nitrates in Kings 

Homosassa, Rock, and Kings Bay Springs are elevated, but there seem to be no distinct trends 

over the four-year period. All other springs had increasing nitrate nitrogen concentrations, with

Fanning, and Jackson Blue at the highest levels.

Table 31. Reference Springs and Statewide Medians for Nitrate Nitrogen

Spring Basin County Spring 

Magnitude1

Total Nitrate-N 

Median 

(mg/L)

Green Cove Springs Lower St. Johns Clay 2 0.002

Beecher Spring Middle St. Johns Putnam 2 0.002

Copper Spring Suwannee Dixie 2 0.002

Holton Creek Rise2 Suwannee Hamilton 1 0.002

Orange Spring (Marion) Ocklawaha Marion 3 0.002

Suwannee Springs Suwannee Suwannee 2 0.002

Newport Spring Ochlockonee–St. Marks Wakulla 3 0.005

Waldo Spring Suwannee Taylor 3 0.007

Warm Mineral Spring Sarasota Bay–

Peace–Myakka

Sarasota 3 0.013

Santa Fe Spring 

(Columbia) Suwannee Columbia 1 0.023

Nutall Rise2 Suwannee Taylor 1 0.029

Silver Glen Springs Middle St. Johns Marion 1 0.049

Alexander Springs Middle St. Johns Lake 1 0.053

Washington Blue Spring 

(Choctawhatchee)

Choctawhatchee–

St. Andrew Washington 2 0.054

Steinhatchee River Rise2 Suwannee Dixie 1 0.056

Santa Fe River Rise 

(Alachua) 2 Santa Fe River Alachua 1 0.058

Reference Springs Overall Median 0.01

Statewide Springs Overall Median 0.58

First-magnitude Springs Overall Median 0.60

Notes:

1 Spring magnitude based on discharge. First-magnitude (1) springs have an average discharge greater than100 cfs; secondmagnitude (2) springs have an average discharge of 10 to 100 cfs. Third-magnitude (3) springs have flows in the range of 1 to 10 

cfs.

2 River rises are included for informational purposes. A river rise is a re-emergence of ground water through a karst feature, a part 

or all of whose waters are derived from surface inflow. 
2008 Integrated Water Quality Assessment for Florida

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Figure 8. Comparison of Nitrate Trends for Selected Springs (2000–06)

LOW MODERATE HIGH VERY HIGH EXTREME

(0-0.2 mg/L) (>0.20-0.50 mg/L) (>0.50 - 1 mg/L) (>1.0 - 3.0 mg/L) (>3.0 - 10.0 mg/L)

ALEXANDER REF ALLEN MILL POND ARIPEKA BONNET APOPKA* 

BEECHER REF BECKTON BUGG (LAKE) BRANFORD CONVICT 

BIG SPRING (JEFFERSON) BLACK (JACKSON) CHASSAHOWITZKA** CRYSTAL (PASCO) FANNING** 

COLUMBIA BRUNSON LANDING DELEON (VOLUSIA)* DEVIL'S EAR (GILCHRIST)** HAYS (JACKSON) 

COPPER REF CORDLE DOUBLE (JACKSON) FALMOUTH JACKSON BLUE** 

FERN HAMMOCK - CYPRESS* GADSEN (JACKSON) GILCHRIST BLUE RUTH (LAFAYETTE) 

GAINER - ELLAVILLE GEMINI GINNIE SHANGRI-LA 

GREEN COVE REF GATOR (HERNANDO) GUARANTO HART 

JUNIPER HOLMES BLUE GULF HAMMOCK LETTUCE LAKE 

MORRISON HORN HOMOSASSA - LAFAYETTE BLUE** 

NEWPORT REF HORNSBY** ICHETUCKNEE** LITHIA/BUCKHORN**

ORANGE (MARION) REF KINGS BAY - LEVY BLUE MADISON BLUE** 

POE NATURAL BRIDGE LITTLE (HERNANDO) MANATEE** 

ROSSETER FENNEY LITTLE RIVER MEARSON 

SALT (MARION) PONCE DE LEON MILL POND (JACKSON) OTTER 

SANTA FE (COLUMBIA) REF RHODES ROCK BLUFF OWENS 

SILVER GLEN REF SALT (HERNANDO) SPRINGBOARD RAINBOW**

SPRING CREEK SANLANDO VOLUSIA BLUE* ROCK (ORANGE) - 

SUWANNEE REF SHEPHERD WAKULLA* RUNNING

TREEHOUSE STARBUCK WEEKI WACHEE** SUN 

WALDO REF SULPHUR CAVE SILVERWARM MINERAL REF SUWANACOOCHEE TELFORD CAVE

WASHINGTON BLUE TURTLE TROY** 

 (CHOCTAWHATCHEE) REF WACISSA** WEKIWA (ORANGE)** 

WASHINGTON BLUE 

(ECONFINA) 

WELAKA 

WILLIFORD 

Notes: 

Springs in bold are included in FDEP routine monitoring.

Springs in italics represent groups or clusters of springs. REF Reference spring selected by lowest nitrates statewide.

** Springs Initiative–monitored spring with elevated nitrate and an increasing trend.

* Springs Initiative–monitored spring with elevated nitrate and a decreasing trend.

- Springs Initiative–monitored spring with elevated nitrate and no discernable trend.

The data used for this assessment were partly from special projects and quarterly monitoring for the Springs Initiative (2000–06). 

Some springs not routinely sampled in the quarterly monitoring may have issues with data sufficiency and were not included in the 

trend analyses. 

A group of 36 springs was used to compare historical, 30-year-old nitrate data with recent 

quarterly sampling data. Median values were calculated for the comparison. Thirty years ago, 

nitrates were already a concern in Florida’s springs, with the majority of the springs with nitrate 

concentrations higher than background and proposed thresholds. The more current data for the 

same springs show that nitrate levels have increased in most of the springs originally having 

nitrate. Also, during this 30-year period, the combined median value for nitrate has more than 

doubled for these springs. Figure 9 shows the historical and recent median nitrate levels in 

representative springs in Florida.
2008 Integrated Water Quality Assessment for Florida

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Figure 9. Comparison of Recent and Historical Nitrate Concentrations in Florida Springs

Note: Historical data are pre-1970; recent data are from 2000–06 sampling.

0 1 2 3 4 5 6

Lithia

Jackson Blue

Crystal

Troy

Fanning

Gilchrist Blue

Baltzell

Falmouth

Ginnie

Manatee

Branford

Silver

Madison Blue

Owens

Rock Bluff

Ponce De Leon

Ichetucknee

Poe

Wakulla

Chasahowitzka

Rainbow

Homosassa

Mill Pond (Columbia)

Hornsby

Guaranto

St. Marks

Spring Creek

Blue Hole

Volusia Blue

Salt

Wekiwatchee

Gainer

Alexander

Juniper

White

Nitrate concentration in milligrams per liter

Recent

Historical
2008 Integrated Water Quality Assessment for Florida

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Figure 10 shows the distribution of nitrate concentrations in individual springs and spring 

clusters. The water quality evidence indicates that elevated nitrate concentrations are often 

associated with relatively near-field sources that lie within spring recharge areas (or 

springsheds). Typical sources include chemical fertilizers associated with agriculture, lawns, 

and turfgrass, and organic sources such as domestic wastewater and animal waste. 

Figure 10. Distribution of Nitrate Concentrations in Springs Monitored by FDEP
2008 Integrated Water Quality Assessment for Florida

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CHAPTER 5: PUBLIC PARTICIPATION

Public Participation Process

The success of Florida’s water resource management program, especially its watershed 

management approach/TMDL Program, depends heavily on input from local watershed 

stakeholders. This process is highly collaborative, and FDEP staff closely coordinate and 

communicate with watershed stakeholders in all phases of the five-year, rotating basin cycle.

During Phase 1, a kickoff meeting is held within each basin to provide an overview of FDEP’s 

watershed management program and cycle, and to solicit data and other relevant information 

needed to complete the initial evaluation of waterbody health. Those attending these meetings 

are asked to provide their email addresses and other contact information, so that they can be 

placed on a basin-specific list to be notified of future meetings and deliverables such as the 

Status Report or the Assessment Report. Also during Phase 1, FDEP staff work closely with 

local monitoring staff to determine when and where additional monitoring is needed. This 

culminates in the preparation of a Strategic Monitoring Plan that is implemented the following 

year, during Phase 2 of the cycle.

The key product of Phase 2 is the Verified List of impaired waters. As discussed in Chapter 3, 

FDEP works with a variety of stakeholders and holds public meetings on developing and 

adopting the Verified Lists for the state’s 29 river basins. Basin-specific draft Verified Lists of 

impaired waters that meet the requirements of the IWR are placed on FDEP’s TMDL Program 

website (available at http://www.dep.state.fl.us/water/tmdl/index.htm) and are also sent on 

request to interested parties via mail or email. Stakeholders are given the opportunity to 

comment on the draft lists in person and/or in writing. As part of the review process, public 

workshops are advertised and held in each basin to help explain the process for developing the 

Verified Lists, exchange information, and encourage public involvement. The workshops are 

noticed in the Florida Administrative Weekly and on the website. If additional information or 

data is provided during the public comment period or before, FDEP typically creates a revised 

draft Verified List for further review and comment before submitting the final proposed list to the 

Secretary for adoption and then to the EPA.

During Phase 3 of the cycle, watershed and waterbody modeling are carried out to develop the 

TMDL and the preliminary allocations to point and nonpoint sources. Interested stakeholders 

are routinely advised of the plan to develop a TMDL in each basin by a variety of means. First, 

under Florida law, a notice is filed in the Florida Administrative Weekly (FAW) to formally 

announce that the FDEP plans to begin work to develop TMDL rules in a particular basin. 

Second, individual announcements for each draft TMDL are noticed in the FAW, which advises 

the public of how they can access the draft TMDL report, how to participate in a workshop that 

must be held in a location convenient to the area of the impaired waterbody, and, finally, and, 

finally, when and how they can provide comments on the draft TMDL report. Third, once a 

TMDL has drafted and edited to address comments, the report is condensed into rule form for 

formal adoption. The proposed rule is noticed in the FAW and all interested stakeholders are 

separately advised using statewide and basin-specific distribution lists. These rules are subject 

to a formal administrative challenge period (under Chapter 120, Florida Statutes) and then sent 

to EPA R4 for their review and approval. 
2008 Integrated Water Quality Assessment for Florida

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A basin working group, formalized during this phase, may begin the process of developing the 

Basin Management Action Plan (BMAP), even at this early stage of TMDL development. FDEP 

works closely with the basin working group and other watershed stakeholders to ensure that 

they understand and support the approaches being undertaken to develop the TMDL.

During Phase 4 of the cycle, the basin working group and other stakeholders—especially 

representatives of local governments, including local elected officials—develop the BMAP. This 

process typically takes about two years and culminates in the adoption of the BMAP by FDEP’s

Secretary.

Both the BMAP and the Verified List of impaired waters are adopted by Secretarial Order, while 

all TMDLs are adopted by rule. Like all official agency actions, these adoptions are subject to 

state administrative procedures set forth in Chapter 120, F.S. Once a BMAP, Verified List, or 

TMDL is adopted, a notice is published in the Florida Administrative Weekly allowing any 

affected party to request an administrative hearing to challenge the adoption.

Responsiveness Summary

As noted, public input is received via email, letters, or oral comments. All public meetings are 

recorded, and specific comments are noted in written meeting summaries. These and any other 

comments received are on permanent file at FDEP. Significant comments typically receive a 

written response. All of FDEP’s responses are also kept in a permanent file maintained by 

FDEP.

All written comments and FDEP’s responses are included in an Appendix to each Water Quality 

Assessment Report; the reports are available at 

http://www.dep.state.fl.us/water/tmdl/stat_rep.htm.
2008 Integrated Water Quality Assessment for Florida

114

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Dahl, T.E. 1990. Wetlands—Losses in the United States, 1780s to 1980s. U.S. Fish and 

Wildlife Service Report to Congress. Washington, D.C.

Fernald, E.A., and E.D. Purdum, Eds. 1998. Water resources atlas of Florida. Tallahassee, 

Florida: Florida State University, Institute of Science and Public Affairs.

Florida Department of Agriculture and Consumer Services. 2006. Shellfish bed closures. 

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Available: http://www.dep.state.fl.us/water/tmdl/stat_rep.htm.

———. Interpretative tool for the assessment of metal enrichment in Florida freshwater 

sediment. January 2003. Available:

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———. February 1, 2004. Standard operating procedures for field activities. DEP-SOP001/01. Available: http://www.dep.state.fl.us/labs/qa/qadocument.htm.

———. Elements of Florida’s Water Monitoring and Assessment Program. December 22, 2004 

(revised March 30, 2005). Tallahassee, Florida: Division of Water Resource Management, 

Bureau of Watershed Management.

———. 2006. Discussion of ground water indicators. Available: http://www.dep.state.fl.us.

———. 2006. STORET Program. Available: http://www.dep.state.fl.us/water/storet/index.htm.

———. 2006. Criteria for surface water quality classifications. Available: 

http://www.dep.state.fl.us/water/wqssp/classes.htm.

———. 2006. Allocation Technical Advisory Committee (ATAC) Report.

———. 2006. Florida’s springs: Protecting native gems. Available: 

———. 2006. South Florida Mercury Science Program. Available:

www.floridasprings.org.

 

http://www.dep.state.fl.us/labs/mercury/index.htm. 
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———. 2006. Drinking Water Program. Available: 

http://www.dep.state.fl.us/water/drinkingwater/index.htm.

Florida Department of Health. 2006. Bacterial contamination and sampling. Available: 

http://esetappsdoh.doh.state.fl.us/irm00beachwater/terms.htm.

———. 2006. Healthy Beaches Program. Beach water sampling results. Available: 

http://esetappsdoh.doh.state.fl.us/irm00beachwater/default.aspx. History. Available: 

http://esetappsdoh.doh.state.fl.us/irm00beachwater/history/hisintro.htm.

———. 2006. Fish consumption advisories. Available: 

———. 2006. Small water systems. Available: 

http://www.doh.state.fl.us/environment/community/fishconsumptionadvisories/index.html.

http://www.doh.state.fl.us/environment/water/index.html.

———. 2006. Beach closures. Available: 

http://esetappsdoh.doh.state.fl.us/irm00beachwater/default.aspx.

Florida LakeWatch. October 1999a. A beginner’s guide to water management: The ABCs. 

Gainesville, Florida: University of Florida, Department of Fisheries and Aquatic Sciences, 

Institute of Food and Agricultural Sciences. Available: 

http://lakewatch.ifas.ufl.edu/circpdffolder/ABCsInt.pdf.

———. October 1999b. November 2000. Florida’s springs: Strategies for protection and 

restoration. Florida Springs Task Force. Available: 

http://www.dep.state.fl.us/springs/reports/floridaspringsreport.pdf.

———. 2006. Available: http://lakewatch.ifas.ufl.edu/.

Frayer, W.E., and J.M. Hefner. 1991. Florida wetlands status and trends, 1970s to 1980s. 

Atlanta, Georgia: U.S. Fish and Wildlife Service, Southeast Region.

Gao, X. 2007. TMDL report: Nutrient TMDLs for the Wekiva River (WBIDs 2956, 2956A, and 

2956C) and Rock Springs Run (WBID 2967), Draft 11/15/07. Tallahassee, Florida: Florida 

Department of Environmental Protection, Watershed Assessment Section.

Gilbert, R.O. 1987. Statistical methods for environmental pollution monitoring. New York, Van 

Nostrand.

Hefner, J.M. 1986. Wetlands of Florida 1950s to 1970s. In: E.D. Estevez, J.Miller, J.Morris, 

and R. Hamman (Eds.). Proceedings of the conference: managing cumulative effects in 

Florida wetlands. New College Environmental Studies Program, Publication No. 37. 

Madison, Wisconsin: Omnipress.

Kushlan, J.A. 1990. Freshwater marshes. In: Myers, R.L., and J.J. Ewel (Eds.). Ecosystems 

of Florida. Orlando, Florida: University of Central Florida Press.

Long, E.R., and L.G. Morgan. 1990. The potential for biological effects of sediment-sorbed 

contaminants tested in the National Status and Trends Program. NOAA Technical 

Memorandum NOS OMA 52. Seattle, Washington: National Oceanic and Atmospheric 

Administration. 

MacDonald, D.D. 1994. Approach to the assessment of sediment quality in Florida coastal 

waters. McDonald Environmental Sciences Ltd.

South Florida Water Management District. 2006. Available: http://www.envirobase.usgs.gov/.
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Stevenson, R.J, A. Pinowska, A. Albertin, and J.O. Sickman. 2007. Ecological condition of alga 

and nutrients in Florida springs: The synthesis report. Michigan State University, 

Department of Zoology, DEP Contract WM858. 

Tiner, R.W., Jr. 1984. Wetlands of the United States: Current status and recent trends.

Washington, D.C.: U.S. Fish and Wildlife Service, National Wetlands Inventory.

U.S. Census Bureau Website. 2006. Available: 

http://quickfacts.census.gov/qfd/states/12000.html.

U.S. Environmental Protection Agency. March 2003. Elements of a state water monitoring and 

assessment program. Washington, D.C.: Office of Wetlands, Oceans and Watersheds. 

EPA 841-B-03-003. Available: http://www.epa.gov/owow/monitoring/elements/.

———. July 29, 2005. Guidance for 2004 assessment, listing, and reporting requirements 

under Sections 303(d) and 305 (b) of the Clean Water Act. Watershed Branch, Office of 

Wetlands, Oceans and Watersheds.

———. 2006a. Ecoregions of Florida. Available: 

http://www.epa.gov/wed/pages/ecoregions/fl_eco.htm.

———. 2006b. Region 4: Total Maximum Daily Loads in Florida. Available: 

http://www.epa.gov/region4/water/tmdl/florida/.

———. 2006c. National STORET Program. http://www.epa.gov/storet/.

U. S. Geological Survey. 2006. Available: http://water.usgs.gov/.

———. 2008. Historical water use by category, 1970–2000. Available: 

http://fl.water.usgs.gov/WaterUse/Historical_Tables_Miscellaneous/florida-historicalcategory.1970-2000.htm.

Vogel, M. April 2006. Economic yearbook 2006: Good migrations. Florida Trend. Available: 

http://www.floridatrend.com/article.asp?id=5795.

Water Quality Association. 2006. Water quality glossary: pH. Available: 

http://www.wqa.org/glossary.cfm?gl=1146.
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APPENDICES

Appendix A. Discussion of Status Network Surface 

Water Indicators for Rivers and Lakes, and Ground 

Water Indicators

Surface Water Indicators for Rivers and Lakes

Fecal Coliform Bacteria

The threshold for fecal coliform bacteria is 400 colonies per 100 milliliters (mL) of water. 

Additionally, twice that number (800) is cited in Rule 62-302, F.A.C., as indicating a highly 

contaminated result used for regulatory purposes. The presence of these bacteria can indicate 

the contamination of a waterway or well and the possible presence of other pathogenic 

organisms.

Fecal coliform bacteria can enter water through the discharge of waste from mammals and 

birds, from agricultural and stormwater runoff, and from untreated human sewage. Septic tanks 

for individual homes can become overloaded during the rainy season and allow untreated 

human wastes to flow into drainage ditches and nearby waters. Agricultural practices such as 

allowing animal wastes to wash into nearby streams during the rainy season, spreading manure 

and fertilizer on fields during rainy periods, and allowing livestock watering in streams can all 

contribute fecal coliform contamination.

Dissolved Oxygen

The state criterion for DO is greater than or equal to 5 mg/L. DO is a measure of water quality 

indicating free oxygen dissolved in water. Oxygen is measured in its dissolved form. If more 

oxygen is consumed than is produced, DO levels decline and some sensitive aquatic animals 

may move away, weaken, or die. Levels vary with water temperature; therefore, cold water 

holds more oxygen than warm water.

Surface water gains oxygen from the atmosphere and plants as a result of photosynthesis. 

Running water contains more oxygen than still water because of its flow. Respiration by aquatic 

animals, decomposition, and various chemical reactions consume oxygen. 

Wastewater from sewage treatment plants often contains organic materials that are 

decomposed by microorganisms, which use oxygen in the process. Other sources of oxygenconsuming waste include stormwater runoff from farmland or urban streets, feedlots, and failing 

septic systems. Ground water is naturally low in DO. Surface water contact with ground water 

seepage or upwelling can cause a natural lowering of DO levels.

pH

The surface water criterion for pH is ≥ 6, ≤ 8.5 su. pH is a measure of the degree of acidity or 

alkalinity of a solution, as measured on a pH scale of 0 to 14. The midpoint of 7.0 on the pH 
2008 Integrated Water Quality Assessment for Florida

118

scale represents neutrality—that is, a neutral solution is neither acid nor alkaline. Numbers 

below 7.0 indicate acidity; numbers above 7.0 indicate alkalinity. 

pH is the negative of the logarithm of the hydrogen ion concentration of a solution. The 

hydrogen ion concentration is the weight of hydrogen ions, in grams, per liter of solution. In

neutral water, for example, the hydrogen ion concentration is 107 grams per liter; the pH is 

therefore 7. 

Hydrogen is responsible for acidity and alkalinity; therefore, the abbreviation "pH" stands for the 

"potential of hydrogen." The neutral point of 7.0 actually indicates the presence of equal 

concentrations of free hydrogen and hydroxide ions.

Acidity increases as pH gets lower. pH affects many chemical and biological processes in 

water. For example, different organisms flourish within different ranges of pH. When pH levels 

are outside this range, aquatic animal diversity is harmed because it stresses the physiological 

systems of most organisms and can reduce reproduction. Low pH can also allow toxic 

elements and compounds to become mobile and "available" for uptake by aquatic plants and 

animals. This can produce conditions that are toxic to aquatic life, particularly to sensitive 

species. Changes in acidity can be caused by atmospheric deposition (acid rain), surrounding 

rock, and certain wastewater discharges.

Unionized Ammonia

The threshold for unionized ammonia is ≤0.02 mg/L as ammonia and is calculated using 

temperature, salinity, ammonia, and pH. This criterion applies to predominantly fresh waters in 

Florida. In water, ammonia occurs in two forms, which together are called total ammonia 

nitrogen, or TAN. Chemically, these two forms are represented as NH4

+ and NH3. NH4+ is 

called ionized ammonia because it has a positive electrical charge, and NH3 is called unionized 

ammonia since it has no charge. Unionized ammonia (abbreviated as UIA), is the form that is 

toxic to fish and invertebrates. Water temperature and pH affect which form of ammonia is 

predominant at any given time in an aquatic system.

Chlorophyll a

The impairment threshold for chlorophyll is ≤ 20 μg/L. This threshold is applied to the rivers and 

streams resources in the Status Monitoring Network. This is not a criterion under Rule 62-302, 

F.A.C.; rather, it is listed as a measure to identify impairment in surface waters in Section 62-

303.351, F.A.C., describing the assessment of nutrients in streams. Chlorophyll is the pigment 

that allows plants—including algae—to convert sunlight into organic compounds during the 

process of photosynthesis. Chlorophyll a is the predominant type found in algae and 

cyanobacteria (blue-green algae), and its abundance is a good indicator of the amount of algae 

present in a surface waterbody.

Excessive quantities of chlorophyll a can indicate the presence of algal blooms. These usually 

consist of a single species of algae, typically a species undesirable for fish and other predators 

to consume. Unconsumed algae sink to the bottom and decay, using up the oxygen required by 

other plants and benthic organisms to survive. The presence of too many nutrients, such as 

nitrogen and phosphorus, can stimulate algal blooms and result in reduced water clarity.
2008 Integrated Water Quality Assessment for Florida

119

Chlorophyll a also plays a direct role in reducing the amount of light available to plants in 

shallow-water habitats. Like their terrestrial cousins, these plants need sunlight to grow. As 

chlorophyll a levels increase, the amount of sunlight reaching underwater plants declines.

Trophic State Index

Lakes are potentially impaired for nutrients if (1) in lakes with a mean color greater than 40 

CUs), the annual mean TSI for the lake exceeds 60, or (2) in lakes with a mean color less than 

or equal to 40 PCUs, the annual mean TSI for the lake exceeds 40. TSI was used as a 

threshold for both large and small lakes in the Status Monitoring Network. 

The TSI classifies lakes based on chlorophyll levels and nitrogen and phosphorus 

concentrations. It is based on a classification scheme that relies on 3 indicators—Secchi depth, 

chlorophyll, and total phosphorus—to describe a lake’s trophic state. A 10-unit change in the 

index represents a doubling or halving of algal biomass.

The Florida TSI is based on the same rationale, but total nitrogen replaces total Secchi depth as 

the third indicator. Attempts in previous 305(b) reports to include Secchi depth have been 

unsuccessful in dark-water lakes and estuaries, where dark waters rather than algae diminish 

transparency.

Note: Both TSI and chlorophyll a are not standards, but thresholds used to estimate the 

condition of state waters. These thresholds are used in the analysis of Status Network data 

based on single samples within a basin during a predetermined index period. The analysis and 

representation of these data are not intended to infer the verification of impairment as defined in 

Rule 62-303, F.A.C., in these waters.

Ground Water Indicators

Analytes with primary drinking water standards have been added to measure the condition of 

Florida’s aquifers. Table A-1 contains the list of analytes with the associated criterion for each 

analyte. Primary standards mean that the criterion for an analyte is based on human health 

effects.

Key indicator contaminants for ground water (e.g., chloride, nitrate, metals, and bacteria) serve 

to assess the general suitability for drinking water purposes. In Cycle 1 of the Status Network, 

aquifer samples were filtered to mitigate well construction factors, and the analytes were 

measured as dissolved constituents. This was changed in Cycle 2 to total constituents in order 

to reflect more closely the water directly from the aquifer. Additionally, standards are measured 

using unfiltered water, and so unfiltered samples allow consistency with standards.

Total Coliform Bacteria

The EPA has determined that the presence of total coliform in ground water is a possible health 

concern. Total coliform is common in the environment and the bacteria generally are not 

harmful themselves. Their presence in drinking water, however, generally is a result of a 

problem with water treatment or the pipes that distribute the water, and indicates that the water 

may be contaminated with organisms that can cause disease. 
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The EPA and the state have set an enforceable drinking water standard for total coliform of 4 

counts per 100 mL to reduce the risk of adverse health effects. Drinking water that meets this 

standard is usually not associated with a health risk from disease-causing bacteria and should 

be considered safe.

Table A-1. Status Network Water Quality Standards for Ground Water

Analyte Criterion/Threshold Use

Total Coliform Bacteria

(# /100 mL) ≤ 4 (sample maximum) Potable water

Arsenic

Cadmium

Chromium

Fluoride

Lead

Sodium

≤ 10 μg/L

≤ 5 μg/L

≤ 100 μg/L

≤ 4 mg/L

≤ 15 μg/L

≤ 160 mg/L

Potable water

Nitrate + Nitrite ≤ 10 mg/L Potable water

Arsenic 

Arsenic, a naturally occurring element, is widely distributed in the earth’s crust. Two main 

categories are found, inorganic and organic arsenic. Inorganic arsenic compounds are mainly 

used to preserve wood. Arsenic in animals and plants combines with carbon and hydrogen to 

form organic arsenic compounds. Organic arsenic compounds are used as pesticides, primarily 

on cotton plants.

Many arsenic compounds can dissolve in water, and can be transported into ground water.

Arsenic can affect human health. Several studies have shown that inorganic arsenic can 

increase the risk of lung, skin, bladder, liver, kidney, and prostate cancers. The World Health 

Organization (WHO), the U. S. Department of Health and Human Services (DHHS), and the 

EPA have determined that inorganic arsenic is a human carcinogen. 

Organic arsenic compounds are less toxic than inorganic arsenic compounds. Exposure to high 

levels of some organic arsenic compounds may cause similar effects to those of inorganic 

arsenic.

Cadmium

The EPA and FDEP set the drinking water standard for cadmium at 5 ppb to protect against the 

risk of adverse health effects. Cadmium, a naturally occurring heavy metal whose chemical 

properties are similar to those of zinc, does not occur uncombined in nature. A byproduct of 
2008 Integrated Water Quality Assessment for Florida

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smelting and refining ores of zinc and lead, it is used for its anticorrosive properties in the 

electroplating of steel, in its sulfide form in the manufacture of paint pigments, and in the 

manufacture of batteries and other electrical components. Cadmium also occurs as a byproduct 

in many chemical fertilizers that are produced from phosphate ores. Cadmium enters the 

ambient air primarily from local smelting operations, it enters soil from local mining operations 

and from chemical fertilizers, and it enters water from fertilizer runoff and/or industrial 

wastewater. 

This inorganic metal is a contaminant in the metals used to galvanize pipe. It generally gets into 

water by corrosion of galvanized pipes or by improper waste disposal. The EPA has set the 

drinking water standard for cadmium at 0.005 parts per million (ppm) to protect against the risk 

of adverse health effects. Drinking water that meets the EPA standard is associated with little to 

none of this risk and is considered safe with respect to cadmium.

Chromium

This inorganic metal, which occurs naturally in the ground, is often used in the electroplating of 

metals. It generally enters water from runoff from old mining operations and improper waste 

disposal from plating operations. Some humans exposed to high levels of chromium suffered 

liver and kidney damage, dermatitis and respiratory problems. The EPA has set the drinking 

water standard for chromium at 0.1 ppm to protect against the risk of adverse health effects. 

Drinking water that meets the EPA standard is associated with little to none of this risk and is 

considered safe with respect to chromium.

Fluoride

Under EPA regulations, fluoride, which occurs naturally in some water supplies, must not 

exceed a concentration of 4.0 mg/L in drinking water. Exposure to drinking water levels above 

4.0 mg/L for many years may result in crippling skeletal fluorosis, a serious bone disorder. 

State regulations require a water system to notify the public when monitoring indicates that the 

fluoride in drinking water exceeds 2.0 mg/L. This is intended to alert families about dental 

problems that might affect children under nine years of age.

Fluoride in children's drinking water at levels of approximately 1 mg/L reduces the number of 

dental cavities. However, some children exposed to levels of fluoride greater than about 2.0 

mg/L may develop dental fluorosis. Dental fluorosis, in its moderate and severe forms, is a 

brown staining and/or pitting of the permanent teeth.

Because dental fluorosis occurs only when developing teeth (before they erupt from the gums) 

are exposed to elevated fluoride levels, households without children are not expected to be 

affected by this level of fluoride. Families with children under the age of nine are encouraged to 

seek other sources of drinking water for their children to avoid the possibility of staining and 

pitting.

Lead

Materials that contain lead have frequently been used in the construction of water supply

distribution systems, and in plumbing systems in private homes and other buildings. The most 

commonly found materials include service lines, pipes, brass and bronze fixtures, and solders 

and fluxes. Lead in these materials can contaminate drinking water as a result of the corrosion 
2008 Integrated Water Quality Assessment for Florida

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that takes place when water comes into contact with those materials. The EPA's national 

primary drinking water regulation requires all public water systems to optimize corrosion control 

to minimize lead contamination resulting from the corrosion of plumbing materials. 

Nitrate-Nitrite

Nitrate is used in fertilizer and is found in sewage and wastes from human and/or farm animals; 

it generally enters drinking water from these activities. Excessive levels of nitrate in drinking 

water have caused serious illness and sometimes death in infants less than 6 months of age. 

The EPA has set the drinking water standard at 10 ppm for nitrate to protect against the risk of 

adverse effects. 

The EPA has also set a drinking water standard for nitrite at 1 ppm. In addition, to allow for the 

fact that the toxicity of nitrate and nitrite are additive, the EPA has established a standard for the 

sum of nitrate and nitrite at 10 ppm. Drinking water that meets the EPA standard is associated 

with little to none of this risk and is considered safe with respect to nitrate.

Sodium 

EPA has set the drinking water standard for sodium (salt) at 160.0 ppm to protect individuals 

who are susceptible to sodium-sensitive hypertension or diseases that cause difficulty in 

regulating body fluid volume. Sodium is monitored so that individuals who have been placed on 

sodium-restricted diets may take the sodium in their water into account. Sodium naturally 

occurs in food and drinking water. Food is the common source of sodium. Drinking water 

contributes only a small fraction (less than 10%) of an individual’s overall sodium intake. 

Sodium levels in drinking water can be increased by ion-exchange softeners at water treatment 

facilities or some point-of-use treatment devices.
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Appendix B. Status Network Surface Water 

Methodology

Florida launched the sampling portion of the Status Network beginning in January 2004 for the 

current reporting cycle. This monitoring network is designed to assess both surface water and 

ground water throughout the state. The design provides an estimate of condition, or status, of 

the state’s numerous and diverse water resources. The implementation of the Status Network 

monitoring enables FDEP to estimate the condition of 100% of accessible aquatic resources in 

the state with a known statistical confidence. Data produced by the Status Network are used to 

complement traditional CWA 305(b) reporting.

The Status Network design for probabilistic monitoring is based on the EPA’s EMAP model. 

The design incorporates a stratified, rotating-basin, multiyear approach to sampling and 

reporting on water resources from the entire state. Figure 4 in Chapter 3 shows the basins 

used as a foundation for Florida’s watershed programs, especially for 303(d) and 305(b) 

reporting. FDEP will be able to answer questions of statewide concern—for example, “what are 

the concentrations of nutrients in Florida's surface waters?" and "are these concentrations 

changing over time?"

Monitoring Design 

A stratified random design to address statewide as well as regional resources was selected, 

using the Generalized Random Tessellation Stratified (GRTS) probabilistic sampling design 

supported by the EPA’s EMAP Program. All stratified random sampling networks use 

predefined geographic subunits (basins) that together comprise the whole state, so that the 

resulting data can address questions at statewide and specific basin scales. As seen in Figure 

4 (Chapter 3), and summarized in Table B-1, the state is divided into 29 basins as the 

foundation for the basin assessments. During the 5-year cycle of the Status Network (January 

2004 through December 2008), all basins will be sampled in a predetermined sequence, using 

the same 5-year rotation as the TMDL Program. At the end of the 5-year cycle, the entire state 

will be sampled.
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Table B-1. Basin Groups for Implementing the Watershed Management Cycle,

by FDEP District Office 

Group 1

Basins

Group 2

Basins

Group 3

Basins

Group 4

Basins

Group 5

Basins

Northwest Ochlockonee–

St. Marks Rivers

Apalachicola–

Chipola Rivers

Choctawhatchee 

River and Bay and 

St. Andrew Bay

Pensacola Bay Perdido River 

and Bay

Northeast Suwannee River Lower St. Johns 

River — St. Marys–Nassau Rivers

Northeast 

Coast Lagoons

Central Ocklawaha River Middle St. Johns 

River

Upper St. Johns 

River Kissimmee River Indian River Lagoon

Southwest Tampa Bay Tampa Bay 

Tributaries

Sarasota Bay and 

Peace–Myakka 

Rivers

Withlacoochee 

River Springs Coast

South Everglades West

Coast Charlotte Harbor Caloosahatchee River Fisheating Creek Florida Keys

Southeast Lake Okeechobee

St. Lucie–

Loxahatchee 

Rivers

Lake Worth 

Lagoon/Palm 

Beach Coast

Southeast Urban 

Coast Everglades

Sampling in the Status Network occurs 1 to 2 years ahead of the TMDL rotation. This schedule 

provides both recently collected data from the region of interest and an estimate of condition for 

4 surface water and 2 ground water resources from each of the 29 basins. Results are provided 

annually to FDEP’s Watershed Assessment Section to complement the information gathered to 

prepare basin reports. Every 2 years, the results of the Tier I sampling of basins are submitted 

to the EPA through the 305(b) reporting process.

Some limitations are inherent in the GRTS sample design, due to the state’s geography. Not all 

resources can be sampled in all basins, depending on how the basins are delineated and 

whether specific resources are actually present. Portions of Florida do not support all the 

“typical” waters used in the sampling design. For example, there are few, if any, true small 

lakes in the southern portions of the state. Or watersheds may split the tributaries to an estuary 

from the upland contributing portion, leaving no stream miles on the estuarine side of the two 

watersheds. Therefore, the ideal number of samples would not be collected.

As in any monitoring program, the placement of sites and the total number of sites are based on 

the assessment questions. Since many of the Tier I monitoring questions require assessments 

for "all" of Florida’s fresh waters, then an element of the sampling design must be extractable 

and thus probabilistic in nature. The use of the term “probabilistic” infers that the sites are 

representative and not biased. Therefore, the use of random selections is adopted from a list 

(list frame) of resources available to sample from each population. The specific protocol for the 

selection of sample sites for each resource type (e.g., small lakes, small streams) is somewhat 

different. Some resources are selected as points, while others are line features, and still others 

are based on area. The base for the state map showing water resources is the revised National 

Hydrography Dataset (rNHD). The following section discusses the selection of the sites.

Geographic Design

Location information for point-feature sites (e.g., wells, small lakes) and electronic 

representations of all other water resources are sent in a GIS file with associated metadata to 
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the EPA in Corvallis, Oregon. Thirty random primary selections and a 5-time oversample, for a 

total of 180 possible selections, are chosen from each resource in each basin. The oversample 

is required because of the high probability of possible sampling problems, such as landowner 

denials of permission, dry resources, possible GIS errors, and other sampling challenges, that 

are routinely associated with random versus fixed station sampling designs.

The 180 potential sample sites are placed into a database and accessed by samplers in an 

Internet-based application called OGWIS. These sites must be sampled in the same order in 

which they were generated from the EPA program. The application allows samplers to review 

selected sites using an Arc Interactive Mapping System (ArcIMS). Initial reconnaissance can 

then be conducted to determine whether the site represents the correct resource, whether 

additional information is needed from the field to determine if the site meets the definition of the 

population being sampled, or even to help determine the easiest access for collecting samples 

at the site.

Water Resource Types 

To sample many different occurrences of water systematically across the state, Florida’s waters

have been subdivided into “resources.” Each resource constitutes a readily identifiable 

occurrence of a water of interest for management purposes. In addition, the scale of a 

waterbody has an effect on sampling strategy and, in many cases, on the management of 

resources, and so the resources have been subdivided to facilitate sampling and resource 

evaluation. The following surface water resources are monitored as part of the Status Network:

• Lakes (2.5 to 25 acres and over 25 acres), and

• Large rivers and small streams (including canals).

Lakes

Lakes are subdivided into two groups: (1) small lakes between 2.5 and 25 acres and (2) large 

lakes over 25 acres. This differentiation on the basis of size is intended to accommodate 

different sampling strategies and methods and allow better representation of the resource. The 

number and size of large lakes would have skewed selection and caused small lakes to be 

under-represented in the sample design, had all lakes been in one category. 

The protocol for site selection for small lakes (between 2.5 and 25 acres) was based on the 

rNHD 1:100,000 scale. All lakes less than 25 acres in size are associated with latitudelongitude coordinates for the center of the lake. A list frame was developed for each basin, and 

180 random selections were chosen in each basin.

The selections of large lakes (over 25 acres) were also based on available coverage from the 

rNHD 1:1000:000 scale. Random point locations were generated based on area; several 

stations may exist in one lake.

Rivers, Streams, and Canals 

Streams and rivers are abundant in Florida, which has approximately 52,000 miles of waters 

including canals and ditches (see the section on Surface Water and Ground Water Resources in 

Chapter 2). Using the 1:100,000 coverage and not counting the estuarine portions of these 
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waterbodies, the statewide estimate of waters in the Status Network listframe is approximately 

48,000 miles. 

The resource was divided into “large rivers” and “small streams” based on the 1:100,000 GIS 

coverage. This division was predetermined by review by water management district and FDEP

project managers. Large rivers were selected as waters of greatest interest or significance 

within the different watersheds. Once the “large rivers” coverage was determined, the 

remaining rivers and streams on the 1:100,000 scale were deemed “small streams.” This also 

allows adequate representation of the large river resource when making sample site selections, 

as the miles of small streams far exceed the large river miles.

Each year approximately 30 random samples are collected from each of the resources in 5 to 6 

basins around the state. Approximately 120 samples are collected for the combined surface 

water resources in addition to quality assurance samples. The indicator list, which consists of 

both chemical and biological parameters, is discussed in Appendix A. The same sampling and 

analytical methodologies are used for all of the basins. 

Proposed indicators may exhibit large intra-annual (seasonal) variability. Generally, monitoring 

programs do not have the monetary resources to characterize this variability, or to assess 

ambient conditions in all seasons for "all" resources (i.e., all of Florida’s fresh waters). 

Therefore, sampling is often limited to a confined portion of the year (index period). Annual 

sampling for the Status Network occurs during different index periods of 4 to 12 weeks for each 

resource type (Table B-2).

A study is under way to answer the question of whether there are significant changes in 

individual measures of condition as a result of the seasonality in the study design. Duplicate 

stations are collected from the same lakes, but will be sampled in different seasons. The results 

will be compared to determine whether the proportional estimate of condition of selected 

indicators is significantly different.

Table B-2. Status Network Primary Index Periods

Resource North Florida Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Confined Aquifers

Unconfined Aquifers

Small Streams

Large Rivers

Small Lakes

Large Lakes

Resource Peninsular Florida Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Confined Aquifers

Unconfined Aquifers

Small Streams

Large Rivers

Small Lakes

Large Lakes
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Appendix C. Impaired Surface Waters Rule

Methodology for Evaluating Impairment for the Basin

Assessments

To determine the status of surface water quality in individual WBIDs in Florida, three categories 

of data—chemistry data, biological data, and fish consumption advisories—are evaluated using 

the IWR methodology to determine potential impairments for four designated use attainment 

categories: aquatic life, primary contact and recreation, fish and shellfish consumption, drinking 

water use, and protection of human health.

Aquatic Life Based Attainment

The IWR follows the principle of independent applicability. A waterbody is listed for potential 

impairment of aquatic life use support based on exceedances of any one of four types of water 

quality indicators (numeric water quality criteria, nutrient thresholds, biological thresholds, and 

toxicity data).

Exceedances of Numeric Water Quality Criteria

The water quality data from STORET used in evaluating impairment were also used in making 

attainment determinations. The assessment of impairment included only ambient surface water 

quality stations. Water quality information from point sources or wells was excluded. Data that 

were determined to be of insufficient quality for TMDL data quality objectives were also 

excluded from the Verified List assessment. Monitoring stations were classified as one of five 

waterbody types—spring, stream, lake, estuary, or blackwater—based on specific criteria. The 

assessments included the following parameters:

Metals Arsenic, aluminum, cadmium, chromium VI, chromium III, 

copper, iron, lead, mercury, nickel, selenium, silver, 

thallium, and zinc

Nutrients Chlorophyll a for streams and estuaries, and TSI 

(chlorophyll a, total nitrogen, and total phosphorus) for 

lakes

Conventionals DO, fecal coliform, pH, unionized ammonia

The requirements for placing waters on the Planning List of potentially impaired waters included 

a minimum of 10 temporally independent samples from the 10-year period of record shown in 

Tables 13a and 13b (in Chapter 3), unless there were 3 exceedances of water quality or 1 

exceedance of an acute toxicity criterion in a 3-year period. The screening methodology for the 

Verified List of impaired waters requires at least 20 samples from the last 7.5 years preceding 

the Planning List assessment. An exceedance, meaning that water quality criteria or standards 

are not met, is recorded any time the criterion is exceeded by any amount. An exceedance for 
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DO, however, means that a waterbody does not meet the DO criterion, rather than an actual 

exceedance of the criterion.

To determine if a water should be placed on the Planning List for each parameter, the chemical 

data were analyzed using a computer program written to assess the data, based on criteria 

established in the IWR, with two exceptions. First, un-onized ammonia data were not analyzed 

by the program, but rather with an Excel spreadsheet. Second, because the full complexity of 

the pH criterion could not be programmed, the incomplete listings for pH were not included, but 

were further examined while additional data were collected during Phase 2 of the watershed 

management cycle. Data analysis and statistical summaries of waterbody identification 

numbers (WBIDs), waterbody types, and parameters obtained from the STORET Database 

were conducted using Access, SAS statistical software, and ArcView GIS applications

The data for metals and conventional parameters were compared with the state surface water 

quality criteria in Section 62-302.530, F.A.C. (IWR). The rule contains a table of sample 

numbers versus exceedances. A waterbody was placed on the Planning List if there was at 

least 80% confidence that the actual criteria exceedance rate was greater than or equal to 10%. 

To be placed on the Verified List, at least a 90% confidence rate was required.

Exceedances of Nutrient Thresholds

The state currently has a narrative nutrient criterion instead of a numeric value for nutrient 

thresholds. The narrative criterion states, “In no case shall nutrient concentrations of a body of 

water be altered so as to cause an imbalance in natural populations of aquatic flora or fauna.” 

The IWR provides an interpretation of the narrative nutrient criterion. In general, the TSI and 

the annual mean chlorophyll a values are the primary means for assessing whether a waterbody 

should be assessed further for nutrient impairment.

The rule also considers other information that might indicate an imbalance in flora or fauna due 

to nutrient enrichment, such as algal blooms, excessive macrophyte growth, a decrease in the 

distribution (either in density or aerial coverage) of seagrasses or other submerged aquatic 

vegetation, changes in algal species richness, and excessive diel oxygen swings.

Potential nutrient impairment was evaluated by calculating annual mean chlorophyll a values for 

estuaries and streams and the TSI for lakes. For lakes, the TSI was calculated using 

chlorophyll a, total phosphorus, and total nitrogen measurements. Direct evidence of 

imbalances of flora and fauna in waterbodies was also considered in the evaluation of nutrient 

impairments.

In estuarine areas, a waterbody was considered nutrient enriched if the annual mean chlorophyll 

a values were greater than 11 μg/L, or if annual mean chlorophyll a values increased by more 

than 50% over historical values for at least 2 consecutive years. For streams, a waterbody was 

considered nutrient enriched if the annual mean chlorophyll a values were greater than 20 μg/L, 

or if the annual mean increased by more than 50% over historical values for at least 2

consecutive years.

A lake with a mean color greater than 40 PCUs was considered nutrient enriched if the annual 

mean TSI exceeded 60. A lake with a mean color less than or equal to 40 PCUs was 

considered nutrient enriched if the annual mean TSI exceeded 40. In addition, a lake was 
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considered nutrient enriched if there was a statistically significant increase in TSI over the last 5-

year period, or if TSI measurements were 10 units higher than historical values.

Exceedances of Biological Thresholds

Bioassessments were carried out for streams, lakes, canals, and rivers using the IWR as 

guidance and following FDEP’s standard operating procedures, which provide definitions and 

specific methods for the generation and analysis of bioassessment data. These are referenced 

in the individual bioassessment data tables contained in the Water Quality Status Reports

(available at http://www.dep.state.fl.us/water/basin411/default.htm). The purpose behind using 

a bioassessment methodology in surface water characterizations is that biological components 

of the environment manifest long-term water quality conditions and thus provide a better 

indication of a waterbody’s true health than discrete chemical or physical measurements alone. 

Biological communities also respond to factors other than water quality, such as habitat 

disruption and hydrologic disturbances. Therefore, to use bioassessment data to list a 

waterbody, FDEP must reasonably demonstrate the pollutant responsible for the observed 

degradation. Recent recalibrations of the SCI and the BioRecon method involved the use of the 

Human Disturbance Gradient (HDG). The HDG ranked sites based on independent 

assessments of habitat quality, the degree of hydrologic disturbance, water quality, and human 

land use intensity. Biological measures (metrics) associated with minimally affected waters in a 

given region were used to set ecoregional expectations.

A metric is a precise measure of biological community structure or function that responds in a 

predictable manner to human disturbance. Metrics (e.g., number of long-lived taxa, number of 

sensitive taxa, % filter feeders, % clingers) were calculated and aggregated into a 

dimensionless, multimetric index. Indices have advantages over individual metrics in that they 

can integrate several nonredundant metrics into a single score that reflects a wider range of 

biological variables. In Florida, multimetric bioassessment indices have been developed for 

vascular plants (aquatic trees, shrubs, and herbaceous macrophytes) and benthic 

macroinvertebrates (animals without a backbone, such as aquatic insects, crayfish, snails, and 

mussels). Efforts to create multimetric indices for periphyton (attached algae) and 

phytoplankton (drifting algae) are currently under way.

Only macroinvertebrate data from ambient sites in state surface waters were used in the 

bioassessments analyzed for the Planning and Verified Lists. The data included sites 

designated as test and background sites for NPDES fifth-year inspections, but excluded data 

from effluent outfalls from discharging facilities, or data from monitoring sites not clearly 

established to collect ambient water quality data. Because site-specific habitat and 

physicochemical assessment information (e.g., % suitable macroinvertebrate habitat, water 

velocities, extent of sand or silt smothering, and riparian [or streamside] buffer zone widths) was 

not available at the time of reporting, it was not included. However, this information is important 

for identifying the stressors responsible for a failed bioassessment and will be included in future 

reporting. Waterbodies that are adversely affected only by pollution (e.g., a lack of habitat or 

hydrologic disruption) but not a pollutant (a water quality exceedance) are not placed on the

Verified List.

The data used to develop the Planning and Verified Lists were obtained from FDEP’s Biological 

Database (SBIO) and the EPA’s STORET Water Quality Database, where it could be 

substantiated that the data were generated in compliance with the bioassessment standard 

operating procedures referenced in the IWR (Section 62-303.330, F.A.C.). The data from these 

databases were used without regard to the randomness of sample site selection. For the 
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purposes of the Status Reports, the seasons were defined as follows: winter (1/1–3/31), spring 

(4/1–6/30), summer (7/1–9/30), and fall (10/1–12/31). The wet season for northern Florida 

generally includes November through March, while the wet season in south Florida is usually 

from June to September, although conditions can vary in the state as a whole.

Lake Condition Index

The scoring of the individual metrics of the Lake Condition Index (LCI), except % Diptera, was 

performed according to the following formula:

100(B/A) where A = the 95 percentile of the reference population and B = observed 

value.

For % Diptera, the following formula was used:

100 (100-B)/(100-A) where A = the 95 percentile of the reference population and B 

= observed value.

An average LCI score was calculated by averaging the scores of the 6 metrics in the method: 

total number of taxa; total number of taxa belonging to the orders Ephemeroptera, Odonata, and 

Trichoptera (EOT taxa); % EOT taxa; Shannon-Wiener Diversity Index score; Hulbert Index 

score; and % Dipteran individuals. LCI calculations were only provided for noncolored lakes 

(< 20 PCUs). As macroinvertebrate-based indices have not been shown to assess colored 

lakes in Florida accurately (> 20 PCUs), they have been excluded from bioassessments. A 

poor or very poor rating based on the average score constituted a failed bioassessment, based 

on the IWR.

Stream Condition Index

A total SCI score was calculated by averaging the scores of the 10 metrics in the method: total 

number of taxa; total number of taxa belonging to the order Ephemeroptera, total taxa of the 

order Trichoptera, % filter feeders, % long-lived taxa, clinger taxa, % dominant taxa, % taxa in 

the Tanytarsini, % sensitive taxa, and % very tolerant taxa (see the table below for calculations). 

A poor or very poor rating based on the total score constituted a failed bioassessment, based on 

the IWR. The Basin Status Reports contain definitions and specific methods for the generation 

and analysis of bioassessment data.
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SCI Metric Northeast Panhandle Peninsula

Total taxa 10 * (X–16)/26 10 * (X–16)/33 10 * (X–16)/25

Ephemeroptera taxa 10 * X /3.5 10 * X /6 10 * X /5

Trichoptera taxa 10 * X /6.5 10 * X /7 10 * X /7

% filterer 10 * (X–1)/41 10 * (X–1)/44 10 * (X–1)/39

Long-lived taxa 10 * X /3 10 * X /5 10 * X /4

Clinger taxa 10 * X /9 10 * X /15.5 10 * X /8

% dominance 10 – ( 10 * [ ( X–10)/44 ] ) 10 – ( 10 * [ ( X–10)/33 ] ) 10 – ( 10 * [ ( X–10)/44 ] )

% Tanytarsini 10 * [ ln( X + 1) /3.3] 10 * [ ln( X + 1) /3.3] 10 * [ ln( X + 1) /3.3]

Sensitive taxa 10 * X /11 10 * X /19 10 * X /9

% Very tolerant 10 – (10 * [ ln( X + 1)/4.4 ] ) 10 – (10 * [ ln( X + 1)/3.6 ] ) 10 – (10 * [ ln( X + 1)/4.1 ] )

BioReconnaissance

To establish an impairment rating based on BioRecon data, the six metrics as calculated in the 

table below were used. 

BioRecon Metric Northeast Panhandle Peninsula

Total taxa (X–14)/23 (X–16)/33 (X–11)/25

Ephemeroptera taxa X /3.5 X /12 X /5

Trichoptera taxa X /6.5 X /7 X /7

Long–lived taxa X /6 X /10 X /7

Clinger taxa X /7 X /15.5 X /8

Sensitive taxa X /11 X /19 X /9

A poor score, based on two BioRecon failures, warrants inclusion on the Verified List.

BioRecon Index Range

1 sample

Pass (6–10)

Fail (0–6)

2 samples

Good (7–10)

Fair (4–7)

Poor (0–4)
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Biological Integrity Standard

Quantitative data, generated through the use of Hester-Dendy artificial substrate samplers, were 

used to calculate Shannon-Wiener Diversity Index scores for paired background and test sites, 

as specified in the Biological Integrity Standard of Subsection 62-302.530(11), F.A.C. One 

failure of the standard meant that a waterbody segment was listed as potentially impaired.

Evaluation of Toxicity Data

Although the IWR describes the use of toxicity data for the assessment of aquatic life-based 

attainment, no ambient toxicity data were available for assessment and this metric was not 

used.

Primary Contact and Recreation Attainment

For Class I, II, or III waters, a waterbody was potentially impaired if the following criteria were 

met:

• The waterbody segment did not meet the applicable water quality criteria for 

bacteriological quality,

• The waterbody segment included a bathing area that was closed by a local 

health department or county government for more than 1 week or more than 

once during a calendar year based on bacteriological data, 

• The waterbody segment included a bathing area for which a local health 

department or county government issued closures, advisories, or warnings 

totaling 21 days or more during a calendar year based on bacteriological data, 

or 

• The waterbody segment included a bathing area that was closed or had 

advisories or warnings for more than 12 weeks during a calendar year based on 

previous bacteriological data or on derived relationships between bacteria 

levels and rainfall or flow.

Fish and Shellfish Consumption Attainment

For Class I, II, or III waters, a waterbody was potentially impaired if it did not meet the applicable 

Class II water quality criteria for bacteriological quality, or if a fish consumption advisory had 

been issued. Fish consumption advisories were based on FDOH’s “limited consumption” or “no 

consumption” advisories for surface waters because of high levels of mercury in fish tissue. In 

addition, for Class II waters, waterbody segments that had been approved for shellfish 

harvesting but were downgraded to a more restrictive classification were listed as potentially 

impaired.
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Drinking Water Attainment and Protection of Human Health

For Class I waters, a waterbody was potentially impaired if it did not meet the applicable Class I 

water quality criteria.
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Appendix D: Impaired Lakes in Florida, Group 1–5 

Basins

Note: The most up-to-date list of verified waters, by basin group, is available at 

http://www.dep.state.fl.us/water/tmdl/.

Lake WBID

Parameter 

Causing

Impairment

Basin 

Group Basin Name

Alachua Sink 2720A Fecal Coliform Group 1 Ocklawaha

Alford Arm 647 DO Group 1 Ochlockonee–St. Marks

Alligator Lake 1574A DO Group 1 Tampa Bay

Alligator Lake 3516A DO Group 1 Suwannee

Alligator Lake 3176 Fish Group 4 Kissimmee River

Alligator Lake 3516A TSI Group 1 Suwannee

Banana Lake 1549B DO Group 3 Sarasota Bay–Peace–Myakka

Banana Lake 1549B TSI Group 3 Sarasota Bay–Peace–Myakka

Bay Lake 3004G TSI Group 2 Middle St. Johns

Bear Gulley Lake 3009 TSI Group 2 Middle St. Johns

Bear Lake 3004A Fish Group 2 Middle St. Johns

Bellows Lake 1579A TSI Group 1 Tampa Bay

Bevens Arm 2718B TSI Group 1 Ocklawaha

Bevens Arm 2718B Turbidity Group 1 Ocklawaha

Blue Cypress Lake 2893V Iron Group 3 Upper St. Johns

Blue Cypress Lake 2893V Fish Group 3 Upper St. Johns

Brick Lake 3177A Fish Group 4 Kissimmee River

Buck Lake 2966A Fish Group 3 Upper St. Johns

Buck Lake 1493E TSI Group 1 Tampa Bay

Calm Lake 1473Y Historical TSI Group 1 Tampa Bay

Cane Lake 3169J TSI Group 4 Kissimmee River

Cedar Lake (East)–

Open Water 1523C TSI Group 2 Tampa Bay Tributaries

Chilton Lake–Open Water 1776A TSI Group 3 Sarasota Bay–Peace–Myakka

Christie Lake 3169S Lead Group 4 Kissimmee River

Clark Lake 1971 TSI Group 3 Sarasota Bay–Peace–Myakka

Clear Lake 3169G TSI Group 4 Kissimmee River

Cowpen Lake 2723A Fish Group 1 Ocklawaha

Crescent Lake 1474V TSI Group 1 Tampa Bay

Crescent Lake 2606B Iron Group 2 Lower St. Johns

Crescent Lake 2606B Fish Group 2 Lower St. Johns

Crescent Lake 2606B TSI Group 2 Lower St. Johns

Crooked Lake 1663 Fish Group 4 Kissimmee River

Dead Lake 2615A Fish Group 2 Lower St. Johns

Deerpoint Lake 553A Fish Group 3 Choctawhatchee–St. Andrew

Doctors Lake 2389 TSI Group 2 Lower St. Johns
2008 Integrated Water Quality Assessment for Florida

135

Lake WBID

Parameter 

Causing

Impairment

Basin 

Group Basin Name

Double Pond 210A Fish Group 3 Choctawhatchee–St. Andrew

Down Lake 3170S Fish Group 4 Kissimmee River

Eagle Lake 1623M TSI Group 3 Sarasota Bay–Peace–Myakka

East Lake Tohopekaliga 3172 Fish Group 4 Kissimmee River

Ella Lake 2797A Fish Group 1 Ocklawaha

Fox Lake 3008A Fish Group 3 Upper St. Johns

Fruitwood Lake 2994Y TSI Group 2 Middle St. Johns

Grasshopper Lake 2916B Fish Group 2 Middle St. Johns

Hampton Lake 3635A Fish Group 1 Suwannee

Hillsborough Reservoir 1443E1 DO Group 2 Tampa Bay Tributaries

Hillsborough Reservoir 1443E1 Fish Group 2 Tampa Bay Tributaries

Hillsborough Reservoir 1443E1 Historical Chlorophyll Group 2 Tampa Bay Tributaries

Hollingsworth Lake 1549X Copper Group 3 Sarasota Bay–Peace–Myakka

Hollingsworth Lake 1549X Fecal Coliform Group 3 Sarasota Bay–Peace–Myakka

Hollingsworth Lake 1549X Lead Group 3 Sarasota Bay–Peace–Myakka

Hollingsworth Lake 1549X TSI Group 3 Sarasota Bay–Peace–Myakka

Hollingsworth Lake 1549X Unionized Ammonia Group 3 Sarasota Bay–Peace–Myakka

Holly Lake 2803A Fish Group 1 Ocklawaha

Howell Lake 2997B TSI Group 2 Middle St. Johns

Huckleberry Lake 1893 TSI Group 4 Kissimmee River

Island Lake 2994D TSI Group 2 Middle St. Johns

Johns Lake 2873C Fish Group 1 Ocklawaha

Johns Lake 2873C TSI Group 1 Ocklawaha

Keene Lake 1451B TSI Group 2 Tampa Bay Tributaries

Konomac Lake Reservoir 2954 Fish Group 2 Middle St. Johns

Lake Adair 2997R TSI Group 2 Middle St. Johns

Lake Agnes 1466 Fish Group 4 Withlacoochee

Lake Alma 2986D TSI Group 2 Middle St. Johns

Lake Altho 3605H Fish Group 1 Suwannee

Lake Annie 1938H Fish Group 4 Kissimmee River

Lake Arbuckle 1685A Fish Group 4 Kissimmee River

Lake Barber 3036A1 Historical Chlorophyll Group 2 Middle St. Johns

Lake Barton 3023B TSI Group 2 Middle St. Johns

Lake Bentley 1549C TSI Group 3 Sarasota Bay–Peace–Myakka

Lake Beresford 2893U TSI Group 2 Middle St. Johns

Lake Bessie 3170T Fish Group 4 Kissimmee River

Lake Bonny 1497E Lead Group 3 Sarasota Bay–Peace–Myakka

Lake Bonny 1497E TSI Group 3 Sarasota Bay–Peace–Myakka

Lake Bryant 2782C Fish Group 1 Ocklawaha

Lake Bryant 2782C TSI Group 1 Ocklawaha

Lake Buckeye 1488S TSI Group 3 Sarasota Bay–Peace–Myakka

Lake Buffum 1677C Fish Group 3 Sarasota Bay–Peace–Myakka

Lake Burkett 3009C TSI Group 2 Middle St. Johns

Lake Burkett 3009C Unionized Ammonia Group 2 Middle St. Johns

Lake Butler 3170Q Fish Group 4 Kissimmee River
2008 Integrated Water Quality Assessment for Florida

136

Lake WBID

Parameter 

Causing

Impairment

Basin 

Group Basin Name

Lake Butler 3170Q Historical TSI Group 4 Kissimmee River

Lake Cannon 1521H TSI Group 3 Sarasota Bay–Peace–Myakka

Lake Cargo 1497D1 TSI Group 3 Sarasota Bay–Peace–Myakka

Lake Catherine 3169P DO Group 4 Kissimmee River

Lake Catherine 3169P TSI Group 4 Kissimmee River

Lake Chase 3170V Fish Group 4 Kissimmee River

Lake Cherry 2839D Fish Group 1 Ocklawaha

Lake Cherry 3322A Fish Group 1 Suwannee

Lake Cherry 2839D Historical TSI Group 1 Ocklawaha

Lake Clarke 3245B DO Group 3 Lake Worth Lagoon–Palm 

Beach Coast

Lake Clarke 3245B Iron Group 3 Lake Worth Lagoon–Palm 

Beach Coast

Lake Clinch 1706 Fish Group 4 Kissimmee River

Lake Concord 2997P TSI Group 2 Middle St. Johns

Lake Cone at Seminole 28932 Fish Group 3 Upper St. Johns

Lake Conine 1488U TSI Group 3 Sarasota Bay–Peace–Myakka

Lake Copeland 3168M TSI Group 4 Kissimmee River

Lake Crosby 3593A Fish Group 1 Suwannee

Lake Cypress 3180A Fish Group 4 Kissimmee River

Lake Cypress 3180A TSI Group 4 Kissimmee River

Lake Davenport–

Open Water 1436A DO Group 4 Kissimmee River

Lake Dead Lady 1474W TSI Group 1 Tampa Bay

Lake Delancey 2894 Fish Group 2 Middle St. Johns

Lake Denham 2832A DO Group 1 Ocklawaha

Lake Denham 2832A TSI Group 1 Ocklawaha

Lake Disston 2630B Iron Group 2 Lower St. Johns

Lake Disston 2630B Fish Group 2 Lower St. Johns

Lake Dorr 2929C Fish Group 2 Middle St. Johns

Lake Dot 2997Q TSI Group 2 Middle St. Johns

Lake Eaton 2771A DO Group 1 Ocklawaha

Lake Eaton 2771A Fish Group 1 Ocklawaha

Lake Eckles–Open Water 1523D TSI Group 2 Tampa Bay Tributaries

Lake Ellen 1176A Fish Group 1 Ochlockonee–St. Marks

Lake Eloise 1521B TSI Group 3 Sarasota Bay–Peace–Myakka

Lake Eustis 2817B DO Group 1 Ocklawaha

Lake Fairview 3004N TSI Group 2 Middle St. Johns

Lake Fannie 14882 TSI Group 3 Sarasota Bay–Peace–Myakka

Lake Formosa 2997M TSI Group 2 Middle St. Johns

Lake Garfield 1622 TSI Group 3 Sarasota Bay–Peace–Myakka

Lake Gentry 3177 Fish Group 4 Kissimmee River

Lake George 2893A Fish Group 2 Middle St. Johns

Lake George 2893A TSI Group 2 Middle St. Johns

Lake George Leftover 2893A3 Fish Group 2 Middle St. Johns

Lake Gibson 1497D Lead Group 3 Sarasota Bay–Peace–Myakka
2008 Integrated Water Quality Assessment for Florida

137

Lake WBID

Parameter 

Causing

Impairment

Basin 

Group Basin Name

Lake Gibson 1497D TSI Group 3 Sarasota Bay–Peace–Myakka

Lake Haines 1488C TSI Group 3 Sarasota Bay–Peace–Myakka

Lake Hancock 1623L DO Group 3 Sarasota Bay–Peace–Myakka

Lake Hancock 1623L TSI Group 3 Sarasota Bay–Peace–Myakka

Lake Hanna 1451T TSI Group 2 Tampa Bay Tributaries

Lake Harney 2964A DO Group 2 Middle St. Johns

Lake Harney 2964A Fish Group 2 Middle St. Johns

Lake Harney 2964A TSI Group 2 Middle St. Johns

Lake Hart 3171 Fish Group 4 Kissimmee River

Lake Hartridge 1521I TSI Group 3 Sarasota Bay–Peace–Myakka

Lake Hatchineha 1472B Fish Group 4 Kissimmee River

Lake Hell ‘n’ Blazes 2893Q DO Group 3 Upper St. Johns

Lake Hell ‘n’ Blazes 2893Q Iron Group 3 Upper St. Johns

Lake Hell ‘n’ Blazes 2893Q Fish Group 3 Upper St. Johns

Lake Hell ‘n’ Blazes 2893Q TSI Group 3 Upper St. Johns

Lake Hicpochee 3237C Lead Group 3 Caloosahatchee

Lake Holden 3168H TSI Group 4 Kissimmee River

Lake Howard 1521F TSI Group 3 Sarasota Bay–Peace–Myakka

Lake Hunter 1543 Lead Group 2 Tampa Bay Tributaries

Lake Hunter 1543 TSI Group 2 Tampa Bay Tributaries

Lake Hunter 1543 Turbidity Group 2 Tampa Bay Tributaries

Lake Idylwild 1521J TSI Group 3 Sarasota Bay–Peace–Myakka

Lake in the Woods 29977 TSI Group 2 Middle St. Johns

Lake Istokpoga 1856B Fish Group 4 Kissimmee River

Lake Istokpoga 1856B Historical TSI Group 4 Kissimmee River

Lake Istokpoga 1856B TSI Group 4 Kissimmee River

Lake Ivanhoe 2997F DO Group 2 Middle St. Johns

Lake Ivanhoe 2997F TSI Group 2 Middle St. Johns

Lake Jackson, 

Osceola County 3183G DO Group 4 Kissimmee River

Lake Jackson, 

Osceola County 3183G TSI Group 4 Kissimmee River

Lake Jessie 1521K TSI Group 3 Sarasota Bay–Peace–Myakka

Lake Jessup 2981 TSI Group 2 Middle St. Johns

Lake Jessup 2981 Unionized Ammonia Group 2 Middle St. Johns

Lake Jessup near the St. 

Johns River 2981A TSI Group 2 Middle St. Johns

Lake Joanna 2821B Historical TSI Group 1 Ocklawaha

Lake Josephine 1860B Fish Group 4 Kissimmee River

Lake Josephine 1860B TSI Group 4 Kissimmee River

Lake Juanita 1473W Historical TSI Group 1 Tampa Bay

Lake June in Winter 1938A Fish Group 4 Kissimmee River

Lake Juniper 283 Fish Group 3 Choctawhatchee–St. Andrew

Lake Kerr 2899B Fish Group 2 Middle St. Johns

Lake Killarney 2997X TSI Group 2 Middle St. Johns

Lake Kissimmee (Middle) 3183B Fish Group 4 Kissimmee River
2008 Integrated Water Quality Assessment for Florida

138

Lake WBID

Parameter 

Causing

Impairment

Basin 

Group Basin Name

Lake Kissimmee (Middle) 3183B TSI Group 4 Kissimmee River

Lake Lawne 3004C TSI Group 2 Middle St. Johns

Lake Lawne 3004C Unionized Ammonia Group 2 Middle St. Johns

Lake Lena 1501 TSI Group 3 Sarasota Bay–Peace–Myakka

Lake Lorna Doone 3169H TSI Group 4 Kissimmee River

Lake Lotta 3002G TSI Group 2 Middle St. Johns

Lake Louisa 2839M DO Group 1 Ocklawaha

Lake Louisa 2839M Fish Group 1 Ocklawaha

Lake Louise 3170W Fish Group 4 Kissimmee River

Lake Lulu 1521 TSI Group 3 Sarasota Bay–Peace–Myakka

Lake Lulu 1521 Unionized Ammonia Group 3 Sarasota Bay–Peace–Myakka

Lake Madelene 1516B TSI Group 1 Tampa Bay

Lake Manatee Reservoir 1807B DO Group 2 Tampa Bay Tributaries

Lake Mann 3169I TSI Group 4 Kissimmee River

Lake Margaret 2892 Fish Group 2 Middle St. Johns

Lake Marian 3184 Fish Group 4 Kissimmee River

Lake Marian 3184 TSI Group 4 Kissimmee River

Lake Marie 2951 TSI Group 2 Middle St. Johns

Lake Marion 3731A DO Group 1 Suwannee

Lake Mary Jane 3171A Fish Group 4 Kissimmee River

Lake Mary Jane 3171A Lead Group 4 Kissimmee River

Lake Maude 1488Q TSI Group 3 Sarasota Bay–Peace–Myakka

Lake May 1521E TSI Group 3 Sarasota Bay–Peace–Myakka

Lake Miccosukee 791N TSI Group 1 Ochlockonee - St. Marks

Lake Minnehaha 2839N Fish Group 1 Ocklawaha

Lake Minnehaha 2997D TSI Group 2 Middle St. Johns

Lake Minneola 2839A Fish Group 1 Ocklawaha

Lake Mirror 1521G TSI Group 3 Sarasota Bay–Peace–Myakka

Lake Molly 2680A TSI Group 2 Lower St. Johns

Lake Monroe 2893D DO Group 2 Middle St. Johns

Lake Monroe 2893D Fish Group 2 Middle St. Johns

Lake Monroe 2893D TSI Group 2 Middle St. Johns

Lake Munson 807C DO Group 1 Ochlockonee–St. Marks

Lake Munson 807C TSI Group 1 Ochlockonee–St. Marks

Lake Munson 807C Turbidity Group 1 Ochlockonee–St. Marks

Lake Nash 1450B Fish Group 5 Springs Coast

Lake Norris 2929B Fish Group 2 Middle St. Johns

Lake Ocklawaha 2740B Fish Group 1 Ocklawaha

Lake Octahatchee 3321A Fish Group 1 Suwannee

Lake Okeechobee 3212A Fish Group 1 Lake Okeechobee

Lake Okeechobee 3212B Fish Group 1 Lake Okeechobee

Lake Okeechobee 3212C Fish Group 1 Lake Okeechobee

Lake Okeechobee 3212D Fish Group 1 Lake Okeechobee

Lake Okeechobee 3212E Fish Group 1 Lake Okeechobee

Lake Okeechobee 3212F Fish Group 1 Lake Okeechobee
2008 Integrated Water Quality Assessment for Florida

139

Lake WBID

Parameter 

Causing

Impairment

Basin 

Group Basin Name

Lake Okeechobee 3212G Fish Group 1 Lake Okeechobee

Lake Okeechobee 3212H Fish Group 1 Lake Okeechobee

Lake Okeechobee 3212I Fish Group 1 Lake Okeechobee

Lake Olive 3168N TSI Group 4 Kissimmee River

Lake Orienta 2998C TSI Group 2 Middle St. Johns

Lake Osborne 3256A DO Group 3 Lake Worth Lagoon–Palm 

Beach Coast

Lake Panasoffkee 1351B DO Group 4 Withlacoochee

Lake Panasoffkee 1351B Fish Group 4 Withlacoochee

Lake Panasoffkee 1351B Historical TSI Group 4 Withlacoochee

Lake Panasoffkee 1351B TSI Group 4 Withlacoochee

Lake Pansy 1488Y TSI Group 3 Sarasota Bay–Peace–Myakka

Lake Park 2997U TSI Group 2 Middle St. Johns

Lake Parker 1497B TSI Group 3 Sarasota Bay–Peace–Myakka

Lake Pickett 3003 Historical Chlorophyll Group 2 Middle St. Johns

Lake Piney Z 756B DO Group 1 Ochlockonee–St. Marks

Lake Piney Z 756B TSI Group 1 Ochlockonee–St. Marks

Lake Placid 1938C Fish Group 4 Kissimmee River

Lake Poinsett 2893K DO Group 3 Upper St. Johns

Lake Poinsett 2893K Fish Group 3 Upper St. Johns

Lake Poinsett 2893K TSI Group 3 Upper St. Johns

Lake Price 3012A Historical TSI Group 2 Middle St. Johns

Lake Primavista 3002E TSI Group 2 Middle St. Johns

Lake Reinheimer–

Open Water 1478H TSI Group 1 Tampa Bay

Lake Rochelle 1488B TSI Group 3 Sarasota Bay–Peace–Myakka

Lake Rose 3004I TSI Group 2 Middle St. Johns

Lake Ross 2543F TSI Group 2 Lower St. Johns

Lake Rousseau 1329B DO Group 4 Withlacoochee

Lake Rousseau 1329B Fish Group 4 Withlacoochee

Lake Rowena 2997J TSI Group 2 Middle St. Johns

Lake Russell 3170B Fish Group 4 Kissimmee River

Lake Sampson 3598D Fish Group 1 Suwannee

Lake Searcy 2986E TSI Group 2 Middle St. Johns

Lake Sebring 1842 Fish Group 4 Kissimmee River

Lake Sheen 3170H Fish Group 4 Kissimmee River

Lake Shipp 1521D TSI Group 3 Sarasota Bay–Peace–Myakka

Lake Silver 1553A TSI Group 2 Tampa Bay Tributaries

Lake Smart 1488A TSI Group 3 Sarasota Bay–Peace–Myakka

Lake Spring 2997S TSI Group 2 Middle St. Johns

Lake Suzy 2033Z TSI Group 3 Sarasota Bay–Peace–Myakka

Lake Talquin 1297C DO Group 1 Ochlockonee–St. Marks

Lake Talquin 1297C Fish Group 1 Ochlockonee–St. Marks

Lake Talquin 1297D Fish Group 1 Ochlockonee–St. Marks

Lake Talquin 1297C TSI Group 1 Ochlockonee–St. Marks

Lake Talquin 1297D TSI Group 1 Ochlockonee–St. Marks
2008 Integrated Water Quality Assessment for Florida

140

Lake WBID

Parameter 

Causing

Impairment

Basin 

Group Basin Name

Lake Tarpon 1486A DO Group 1 Tampa Bay

Lake Tarpon 1486A Historical TSI Group 1 Tampa Bay

Lake Thonotosassa 1522B Fecal Coliform Group 2 Tampa Bay Tributaries

Lake Thonotosassa 1522B Historical Chlorophyll Group 2 Tampa Bay Tributaries

Lake Thonotosassa 1522B Lead Group 2 Tampa Bay Tributaries

Lake Thonotosassa 1522B TSI Group 2 Tampa Bay Tributaries

Lake Thonotosassa 1522B Unionized Ammonia Group 2 Tampa Bay Tributaries

Lake Tibet Butler 3170Y Fish Group 4 Kissimmee River

Lake Tohopekaliga 3173A Fish Group 4 Kissimmee River

Lake Trafford 3259W DO Group 1 Everglades West Coast

Lake Trafford 3259W TSI Group 1 Everglades West Coast

Lake Trafford 3259W Unionized Ammonia Group 1 Everglades West Coast

Lake Underhill 3168G TSI Group 4 Kissimmee River

Lake Valrico 1547A TSI Group 2 Tampa Bay Tributaries

Lake Washington 2893O Fish Group 3 Upper St. Johns

Lake Weeks 971B DO Group 1 Ochlockonee–St. Marks

Lake Weeks–Open Water 1547C TSI Group 2 Tampa Bay Tributaries

Lake Weir 2790A Fish Group 1 Ocklawaha

Lake Weir 2790A TSI Group 1 Ocklawaha

Lake Winder 2893Y Fish Group 3 Upper St. Johns

Lake Winterset 1521A TSI Group 3 Sarasota Bay–Peace–Myakka

Lake Winyah 2997L TSI Group 2 Middle St. Johns

Lake Woodruff 2921 Fish Group 2 Middle St. Johns

Little Hickory Bay 3259Z Fish Group 1 Everglades West Coast

Little Lake Fairview 3004H TSI Group 2 Middle St. Johns

Livingston Lake 1730B Fish Group 4 Kissimmee River

Lake Winnemissett 2931 Lead Group 2 Middle St. Johns

Lochloosa Lake 2738A TSI Group 1 Ocklawaha

Lower Lake 3496A DO Group 1 Suwannee

Lower Lake Lafayette 756C DO Group 1 Ochlockonee–St. Marks

Lower Lake Lafayette 756C TSI Group 1 Ochlockonee–St. Marks

Mill Dam Lake 2779A Fish Group 1 Ocklawaha

Moccasin Creek 1530A DO Group 1 Tampa Bay

Moccasin Creek 1530A Fecal Coliform Group 1 Tampa Bay

Moccasin Creek 1530A TSI Group 1 Tampa Bay

Moore Lake 889A Fish Group 1 Ochlockonee–St. Marks

Mound Lake 1473X Historical TSI Group 1 Tampa Bay

Mud Lake 2893J Fish Group 2 Middle St. Johns

Mud Lake 1467 TSI Group 4 Withlacoochee

Mullet Lake 2893H Fish Group 2 Middle St. Johns

Newnans Lake 2705B DO Group 1 Ocklawaha

Ocean Pond 2339 Fish Group 4 Nassau–St. Marys

Orange Lake 2749A DO Group 1 Ocklawaha

Orange Lake Reach 2749 DO Group 1 Ocklawaha

Persimmon Lake 1938E TSI Group 4 Kissimmee River
2008 Integrated Water Quality Assessment for Florida

141

Lake WBID

Parameter 

Causing

Impairment

Basin 

Group Basin Name

Lake Pineloch 3168I TSI Group 4 Kissimmee River

Pocket Lake 3170Z Fish Group 4 Kissimmee River

Prairie Lake 3002N TSI Group 2 Middle St. Johns

Puzzle Lake 2964B Fish Group 3 Upper St. Johns

Rattlesnake Slough 1923 DO Group 2 Tampa Bay Tributaries

Rattlesnake Slough 1923 Fecal Coliform Group 2 Tampa Bay Tributaries

Rattlesnake Slough 1923 Historical Chlorophyll Group 2 Tampa Bay Tributaries

Rattlesnake Slough 1923 TSI Group 2 Tampa Bay Tributaries

Reclaimed Mine Cut Lake 1623X TSI Group 3 Sarasota Bay–Peace–Myakka

Red Lake 3171C Copper Group 4 Kissimmee River

Redwater Lake 2713B TSI Group 1 Ocklawaha

Rock Lake 3169Q TSI Group 4 Kissimmee River

Ruth Lake 2964C Fish Group 3 Upper St. Johns

Sand Hammock Pond 61A Fish Group 3 Choctawhatchee–St. Andrew

Santa Fe Lake 3605G Fish Group 1 Suwannee

Sawgrass Lake 28931 DO Group 3 Upper St. Johns

Sawgrass Lake 28931 Fish Group 3 Upper St. Johns

Shell Creek Reservoir 

(Hamilton Reservoir) 2041B DO Group 3 Sarasota Bay–Peace–Myakka

Silver Lake 2825A TSI Group 1 Ocklawaha

Silver Lake 3004D TSI Group 2 Middle St. Johns

Silver Lake 3004D Unionized Ammonia Group 2 Middle St. Johns

Smith Lake 2785A Fish Group 1 Ocklawaha

South Lake 3008B Fish Group 3 Upper St. Johns

South Lake Talmadge 2630I TSI Group 2 Lower St. Johns

Spirit Lake 1501V TSI Group 3 Sarasota Bay–Peace–Myakka

Spring Lake 2987A TSI Group 2 Middle St. Johns

Starke Lake 3002D TSI Group 2 Middle St. Johns

St. Johns River above 

Black Creek 2213I Silver Group 2 Lower St. Johns

St. Johns River above 

Black Creek 2213I Fish Group 2 Lower St. Johns

St. Johns River above 

Black Creek 2213I TSI Group 2 Lower St. Johns

St. Johns River above 

Doctor Lake 2213G Cadmium Group 2 Lower St. Johns

St. Johns River above 

Doctor Lake 2213G Fish Group 2 Lower St. Johns

St. Johns River above 

Federal Point 2213L Fish Group 2 Lower St. Johns

St. Johns River above 

Federal Point 2213L TSI Group 2 Lower St. Johns

St. Johns River above 

Julington Creek 2213H Fish Group 2 Lower St. Johns

St. Johns River above 

Palmo Creek 2213J Fish Group 2 Lower St. Johns

St. Johns River above 

Palmo Creek 2213J TSI Group 2 Lower St. Johns

St. Johns River above 

Tocio 2213K Fish Group 2 Lower St. Johns
2008 Integrated Water Quality Assessment for Florida

142

Lake WBID

Parameter 

Causing

Impairment

Basin 

Group Basin Name

St. Johns River above 

Tocio 2213K TSI Group 2 Lower St. Johns

Sunset Lake 1496A TSI Group 1 Tampa Bay

Tallavanna Lake 540A TSI Group 1 Ochlockonee–St. Marks

Tiger Lake 1573A Fish Group 4 Kissimmee River

Trout Lake 2819A DO Group 1 Ocklawaha

Twin Lake–Open Water 1440D TSI Group 2 Tampa Bay Tributaries

Upper Lake Lafayette 756A DO Group 1 Ochlockonee–St. Marks

Upper Lake Lafayette 756A Fecal Coliform Group 1 Ochlockonee–St. Marks

Ward Lake 1914A TSI Group 2 Tampa Bay Tributaries

Waunatta Lake 3009A TSI Group 2 Middle St. Johns