Skip to main content
LakeQuality
A storm cloud deck moving over Slim Lake at dusk, the last light breaking through low on the horizon

Impaired Lakes in Florida

244 of 2,012 measured Florida lakes (12%) are officially listed as impaired under Clean Water Act §303(d) in the most recent EPA ATTAINS reporting cycle. 146 have an approved TMDL restoration plan.

Top Causes of Impairment in Florida

107
Nutrients (phosphorus, nitrogen)
95
Algal growth
83
Mercury
63
Impaired biota (cause unknown)
42
pH / acidity
17
Oxygen depletion (low DO)
10
Metals (other than mercury)
6
Pathogens (E. coli, fecal)

Reading the Florida impairment landscape

244 of Florida's 2,012 tracked lakes carry impaired-waters listings — 12%. That's a meaningful minority worth checking before specific trips, particularly for swimming, fishing, or drinking-water source identification. Most Florida lakes are unimpaired; the impaired set tends to concentrate in agricultural, post-industrial, or high-development watersheds rather than being randomly distributed.

The leading impairment category in Florida is Nutrients (phosphorus, nitrogen) — nutrient enrichment, typically from agricultural fertilizer runoff, septic discharge, or stormwater carrying lawn-care residue. Nutrient-impaired lakes can still be safe for contact recreation in many conditions, but they're prone to algal blooms (including potentially toxic cyanobacteria) during warm-water periods. Check the state's beach-monitoring or harmful-algal-bloom dashboard before swimming on nutrient-impaired waters in summer.

Impaired-waters listings come from the state environmental agency's §303(d) submission to EPA, refreshed on a roughly 2-year cycle. A listed lake stays on the list until either a TMDL is established and the cleanup completes, or subsequent monitoring shows the pollutant concentrations no longer exceed water-quality standards. The list below reflects the most recent available Florida submission to the EPA Assessment, Total Maximum Daily Load Tracking and Implementation System (ATTAINS) dataset.

All 244 EPA-Listed Impaired Lakes in Florida

LakeCountyCausesTMDL
Spring LakeSeminoleNutrients (phosphorus, nitrogen)✓
Lake-EmmaLakeMercury✓
Bear Gully LakeSeminoleAlgal growth, Nutrients (phosphorus, nitrogen)✓
Lake-LouisaLakeMercury, pH / acidity✓
Lake-JoannaLakeMercury✓
Lake GlenadaHighlandsAlgal growth✓
Lake DruidOrangeOxygen depletion (low DO)—
Horseshoe North LakeSeminolepH / acidity—
Lake-DorrLakeMercury✓
Park LakeOrangeImpaired biota (cause unknown)—
Lake-FlorenceLakeAlgal growth, Impaired biota (cause unknown)—
Little Lake JacksonHighlandsAlgal growth, Impaired biota (cause unknown)—
Lake-Little HarrisLakeNutrients (phosphorus, nitrogen)✓
Bass LakeOrangeAlgal growth, Nutrients (phosphorus, nitrogen)—
Buck LakeSeminolepH / acidity—
Buck LakeHighlandsNutrients (phosphorus, nitrogen)—
Little Fish LakeOrangeMercury✓
Lake-BearLakepH / acidity—
Lake-LorraineLakeOxygen depletion (low DO)—
Lake IamoniaLeonMercury, Oxygen depletion (low DO), pH / acidity✓
Lake-EustisLakeImpaired biota (cause unknown), Nutrients (phosphorus, nitrogen)✓
Bay LakeOrangeNutrients (phosphorus, nitrogen)✓
Down LakeOrangeMercury✓
Griffin LakeLakeAlgal growth, Nutrients (phosphorus, nitrogen)✓
Lake-WildcatLakeMercury✓
Tanner LakeOrangepH / acidity—
Louise LakeOrangeMercury✓
Palm LakeOrangepH / acidity—
Lake FrancisHighlandsAlgal growth—
Carr LakeLeonpH / acidity—
Yankee LakeSeminolepH / acidity—
Starke LakeOrangeAlgal growth, Nutrients (phosphorus, nitrogen)—
Carlton LakeOrangeAlgal growth, Impaired biota (cause unknown), Nutrients (phosphorus, nitrogen)✓
Lake ApthorpeHighlandsMercury✓
Lake BrantleySeminoleMercury✓
Lake TarponPinellasAlgal growth, Impaired biota (cause unknown), Mercury✓
Weston LakeOrangeAlgal growth, Nutrients (phosphorus, nitrogen)—
Bearhead LakeOrangeImpaired biota (cause unknown)—
Pocket LakeOrangeMercury✓
Marshall LakeOrangeAlgal growth, Impaired biota (cause unknown), Nutrients (phosphorus, nitrogen)✓
Lovely LakeOrangeAlgal growth—
Mary Jane LakeOrangeMercury, Metals (other than mercury), pH / acidity✓
Sheen LakeOrangeMercury✓
Dias LakeVolusiaMercury✓
Lake GriffinLakeAlgal growth, Nutrients (phosphorus, nitrogen)✓
Hart LakeOrangeMercury, Metals (other than mercury), pH / acidity✓
Amory LakeSeminoleImpaired biota (cause unknown), Oxygen depletion (low DO)—
Cascade LakeLeonMetals (other than mercury), pH / acidity—
Mccoy LakeOrangeImpaired biota (cause unknown)—
Davis LakeCitrusMercury, Oxygen depletion (low DO)✓
Lake AndersonOrangeAlgal growth, Nutrients (phosphorus, nitrogen)✓
Nan LakeOrangeImpaired biota (cause unknown)—
Dosson LakeHillsboroughImpaired biota (cause unknown)—
Prima Vista LakeOrangeAlgal growth, Impaired biota (cause unknown), Nutrients (phosphorus, nitrogen)—
Garden LakeSeminoleImpaired biota (cause unknown)—
Minneola LakeLakeImpaired biota (cause unknown), Mercury✓
Bumby LakeOrangeAlgal growth, Metals (other than mercury), Nutrients (phosphorus, nitrogen)✓
Pearl LakeOrangepH / acidity—
Pearl LakeOrangeImpaired biota (cause unknown)—
Beauclair LakeLakeAlgal growth, Nutrients (phosphorus, nitrogen)✓
Whitetrout LakeHillsboroughImpaired biota (cause unknown)—
Bear LakeSeminoleMercury✓
Lake MarionSeminoleImpaired biota (cause unknown)—
Lake HiawathaLeonpH / acidity—
Lake ArnoldOrangeAlgal growth, Nutrients (phosphorus, nitrogen)—
Lake JacksonLeonMercury, Oxygen depletion (low DO), pH / acidity✓
Deforest LakeSeminoleOxygen depletion (low DO)—
Irma LakeOrangepH / acidity—
Lake-YaleLakeMercury, Nutrients (phosphorus, nitrogen)✓
Lake WinyahOrangeAlgal growth, Impaired biota (cause unknown)—
Lake SeminarySeminolepH / acidity—
Lake AnnSeminoleImpaired biota (cause unknown)—
Lindsey LakeHernandoOxygen depletion (low DO)—
Lake SilverOrangeNutrients (phosphorus, nitrogen)✓
Butler LakeOrangeMercury✓
Lake GilesOrangeAlgal growth, Nutrients (phosphorus, nitrogen)—
Lake ConcordSeminoleAlgal growth, Nutrients (phosphorus, nitrogen)—
Lake ConcordOrangeImpaired biota (cause unknown)—
Sylvan LakeSeminoleMercury, pH / acidity✓
Lake Piney-ZLeonAlgal growth, Mercury, Nutrients (phosphorus, nitrogen)✓
Lake MillsSeminolepH / acidity—
Bessie LakeOrangeMercury✓
Lake GlonaLakeMercury✓
Lake-MinnehahaLakeMercury✓
Tyler LakeOrangeImpaired biota (cause unknown)—
Lake WeeksLeonpH / acidity—
Lake ProctorSeminoleOxygen depletion (low DO)—
Lake HarrisLakeNutrients (phosphorus, nitrogen)✓
Lake LindaPascoImpaired biota (cause unknown)—
Lake AnnieHighlandsMercury, pH / acidity✓
Lake LotelaHighlandsAlgal growth, Mercury✓
Lake LucienOrangeMercury✓
Cooter LakeCitrusImpaired biota (cause unknown), Oxygen depletion (low DO)—
Henderson LakeCitrusMercury✓
Lake LettaHighlandsImpaired biota (cause unknown)—
Munson LakeLeonAlgal growth, Metals (other than mercury), Nutrients (phosphorus, nitrogen)✓
Johns LakeOrangeImpaired biota (cause unknown), Mercury✓
Tussock LakeCitrusOxygen depletion (low DO)—
Bird LakeHillsboroughImpaired biota (cause unknown)—
Lake HenryHighlandsAlgal growth, Nutrients (phosphorus, nitrogen)—
Lake-UmatillaLakeImpaired biota (cause unknown)—
Lake SmartPolkAlgal growth, Nutrients (phosphorus, nitrogen)✓
Red Water LakeHighlandsAlgal growth, Nutrients (phosphorus, nitrogen), pH / acidity✓
Blue LakeHighlandsImpaired biota (cause unknown), Nutrients (phosphorus, nitrogen)—
Cherry LakeMadisonAlgal growth, Mercury✓
Dora LakeLakeAlgal growth, Nutrients (phosphorus, nitrogen)✓
Mckay Creek LakePinellasNoxious aquatic plants, Pathogens (E. coli, fecal)✓
Lake Tom JohnLeonAlgal growth, Mercury, Nutrients (phosphorus, nitrogen)✓
Lake of the WoodsSeminolepH / acidity—
Sandy LakeOrangeNutrients (phosphorus, nitrogen)—
Lotta LakeOrangeAlgal growth, Impaired biota (cause unknown)✓
Roberts LakeOrangeAlgal growth, Nutrients (phosphorus, nitrogen)✓
Crystal LakePolkAlgal growth, Nutrients (phosphorus, nitrogen)✓
Queens Mirror LakeSeminoleAlgal growth—
Tilden LakeOrangeImpaired biota (cause unknown)—
Huckleberry LakeHighlandsAlgal growth, Nutrients (phosphorus, nitrogen)✓
Lake EolaOrangeAlgal growth—
Lake HowellSeminoleImpaired biota (cause unknown)—
Lake TerraceOrangeAlgal growth, Nutrients (phosphorus, nitrogen)—
Lake BuffumPolkImpaired biota (cause unknown), Mercury✓
Lake Tarpon CanalPinellasAlgal growth, Mercury✓
Lake RochellePolkImpaired biota (cause unknown), Nutrients (phosphorus, nitrogen)✓
Alligator LakeColumbiaAlgal growth, Impaired biota (cause unknown), Nutrients (phosphorus, nitrogen)✓
Lake MaggiorePinellasAlgal growth, Nutrients (phosphorus, nitrogen), Salinity / chlorides—
Lake BeardallOrangeNutrients (phosphorus, nitrogen)—
Alligator LakePinellasImpaired biota (cause unknown), Nutrients (phosphorus, nitrogen)—
Irvin LakeHernandoImpaired biota (cause unknown)—
Lake MonroeVolusiaAlgal growth, Impaired biota (cause unknown), Mercury +2 more✓
Lake of the WoodsOrangeNutrients (phosphorus, nitrogen)—
Lake WadeOrangeAlgal growth, Nutrients (phosphorus, nitrogen)✓
Tiger LakePolkMercury, Nutrients (phosphorus, nitrogen)✓
Lake RichmondOrangeAlgal growth, Nutrients (phosphorus, nitrogen)✓
Lake SeminolePinellasAlgal growth, Nutrients (phosphorus, nitrogen), pH / acidity—
Lake SeminolePinellasAlgal growth, Nutrients (phosphorus, nitrogen), pH / acidity—
Lake FranOrangeAlgal growth, Nutrients (phosphorus, nitrogen)✓
Lake HancockPolkAlgal growth, Impaired biota (cause unknown), Nutrients (phosphorus, nitrogen) +1 more✓
Lake OkeechobeePalm BeachMercury, Metals (other than mercury), Nutrients (phosphorus, nitrogen) +1 more✓
Lake DavisOrangeAlgal growth, Nutrients (phosphorus, nitrogen), Pathogens (E. coli, fecal)✓
Kelly LakeOrangeAlgal growth, Nutrients (phosphorus, nitrogen)—
Lake LawsonaOrangeAlgal growth, Nutrients (phosphorus, nitrogen)—
Lake WeldonaOrangeAlgal growth, Nutrients (phosphorus, nitrogen)✓
Apopka LakeOrangeAlgal growth, Nutrients (phosphorus, nitrogen), Pesticides✓
Lake SeminolePinellasAlgal growth, Nutrients (phosphorus, nitrogen), pH / acidity—
Lake Talquin WestGadsdenAlgal growth, Mercury, Nutrients (phosphorus, nitrogen)✓
Lake AdairOrangeAlgal growth, Nutrients (phosphorus, nitrogen)✓
Dead LakeFlaglerMercury✓
Lake TraffordCollierAlgal growth, Nutrients (phosphorus, nitrogen)✓
Kasey LakeOrangeAlgal growth, Impaired biota (cause unknown), Nutrients (phosphorus, nitrogen) +1 more✓
Fox LakeBrevardMercury✓
Kinsale LakeLeonAlgal growth, Nutrients (phosphorus, nitrogen)—
Condel LakeOrangeAlgal growth, Metals (other than mercury), Nutrients (phosphorus, nitrogen) +1 more✓
Lake HainesPolkAlgal growth, Impaired biota (cause unknown), Nutrients (phosphorus, nitrogen)✓
Lake CragoPolkAlgal growth, Nutrients (phosphorus, nitrogen)—
Tallavana LakeGadsdenAlgal growth, Impaired biota (cause unknown), Nutrients (phosphorus, nitrogen) +2 more✓
Doctor'S LakeClayAlgal growth, Nutrients (phosphorus, nitrogen)✓
Doctor'S LakeClayAlgal growth, Nutrients (phosphorus, nitrogen)✓
Lake ThonotosassaHillsboroughAlgal growth, Impaired biota (cause unknown), Nutrients (phosphorus, nitrogen)✓
Lake IstokpogaHighlandsAlgal growth, Mercury, Nutrients (phosphorus, nitrogen) +1 more✓
Doctors LakeClayAlgal growth, Nutrients (phosphorus, nitrogen)✓
Blue Cove LakeMarionImpaired biota (cause unknown), Nutrients (phosphorus, nitrogen)—
Lake VedraSt. JohnsAlgal growth, Nutrients (phosphorus, nitrogen)—
Denham LakeLakeAlgal growth, Nutrients (phosphorus, nitrogen)✓
Lake OliveOrangeImpaired biota (cause unknown)—
Lake NorrisLakeMercury, Metals (other than mercury)✓
Sweetwater Creek LakeSeminoleImpaired biota (cause unknown), Nutrients (phosphorus, nitrogen)—
Alligator Creek LakePinellasAlgal growth, Nutrients (phosphorus, nitrogen)✓
Mirror LakeLakepH / acidity—
Lake FrancisMadisonAlgal growth, Nutrients (phosphorus, nitrogen)—
Lake WaubergAlachuaAlgal growth, Nutrients (phosphorus, nitrogen)✓
Joanna LakeLakeMercury✓
Tank LakeHernandoOxygen depletion (low DO)—
Lake HunterPolkAlgal growth, Nutrients (phosphorus, nitrogen)✓
Gap LakeWashingtonMercury✓
James LakeHillsboroughImpaired biota (cause unknown)—
Lake GrassyHighlandsMercury✓
Lake MarionPolkAlgal growth, Mercury, Nutrients (phosphorus, nitrogen)✓
Lake JacksonWaltonMercury✓
Lake JacksonHighlandsImpaired biota (cause unknown), Mercury✓
Lake VirginiaHillsboroughImpaired biota (cause unknown)—
Lake EdenSt. LuciepH / acidity—
Lake DeerPolkNutrients (phosphorus, nitrogen)✓
Lake ClinchPolkAlgal growth, Mercury, Nutrients (phosphorus, nitrogen) +1 more✓
Isabell LakePolkpH / acidity—
Lake GarfieldPolkMercury✓
Henderson LakeCitrusMercury✓
Lake ArianaPolkAlgal growth, Nutrients (phosphorus, nitrogen)✓
Lochloosa LakeAlachuaNutrients (phosphorus, nitrogen)✓
Yale LakeLakeMercury, Nutrients (phosphorus, nitrogen)✓
Lake IdaPalm BeachAlgal growth, Impaired biota (cause unknown), Nutrients (phosphorus, nitrogen)✓
Lake HoldenOrangeImpaired biota (cause unknown), Nutrients (phosphorus, nitrogen)✓
Lake CopelandOrangeImpaired biota (cause unknown), Nutrients (phosphorus, nitrogen)—
Lake ThomasPascoAlgal growth, Nutrients (phosphorus, nitrogen)—
Lake RowellBradfordImpaired biota (cause unknown), Mercury, pH / acidity✓
Lake SebringHighlandsMercury✓
Persimmon LakeHighlandsAlgal growth, Nutrients (phosphorus, nitrogen), pH / acidity✓
Lake MinnehahaLakeMercury✓
Newnan'S LakeAlachuaAlgal growth, Nutrients (phosphorus, nitrogen)✓
Lake ClayHighlandsMercury✓
Lake DisstonFlaglerMercury, Metals (other than mercury), pH / acidity✓
Lake WashingtonBrevardImpaired biota (cause unknown), Mercury✓
Harris LakeLakeNutrients (phosphorus, nitrogen)✓
Lake CarrieHighlandsImpaired biota (cause unknown)—
Lake PickettOrangeMercury, pH / acidity✓
Lake ConinePolkAlgal growth, Impaired biota (cause unknown), Nutrients (phosphorus, nitrogen)✓
Compass LakeJacksonMercury✓
Lake ManateeManateeImpaired biota (cause unknown), Mercury, Pathogens (E. coli, fecal)✓
Lake HollingsworthPolkAlgal growth, Nutrients (phosphorus, nitrogen)✓
Alligator LakeOsceolaMercury✓
Lake PlacidHighlandsAlgal growth, Mercury✓
Lake JulianaPolkNutrients (phosphorus, nitrogen)✓
Lake DrawdyOrangepH / acidity—
Lake AlfredPolkAlgal growth, Nutrients (phosphorus, nitrogen)✓
Lake WeohyakapkaPolkMercury, pH / acidity✓
Lake WorrellPascoOxygen depletion (low DO)—
Gooseneck LakePascoOxygen depletion (low DO)—
Ashby LakeVolusiaImpaired biota (cause unknown), Mercury✓
Lake ConwayOrangeMercury✓
Newnans LakeAlachuaAlgal growth, Nutrients (phosphorus, nitrogen)✓
Lake SampsonBradfordMercury, pH / acidity✓
Spring Garden LakeVolusiaMercury✓
Lake GibsonPolkAlgal growth, Nutrients (phosphorus, nitrogen)—
Petty Gulf LakeLeonAlgal growth, Impaired biota (cause unknown), Nutrients (phosphorus, nitrogen)—
Cannon LakePolkAlgal growth, Nutrients (phosphorus, nitrogen), pH / acidity✓
Minnehaha LakeLakeMercury✓
Lake AllenHillsboroughImpaired biota (cause unknown)—
Lake ParkerPolkAlgal growth, Impaired biota (cause unknown), Nutrients (phosphorus, nitrogen)✓
Dexter LakeVolusiaMercury✓
Lake Santa FeAlachuaMercury, pH / acidity✓
Big Sand LakeOrangeMercury, Metals (other than mercury)✓
Lake RosaliePolkImpaired biota (cause unknown)—
Lake EarlOkaloosaMercury✓
Lake BonnyPolkAlgal growth, Nutrients (phosphorus, nitrogen), pH / acidity✓
Lake RousseauCitrusMercury✓
Lake BrowardPutnamMercury✓
Lake OkeechobeePalm BeachMercury, Nutrients (phosphorus, nitrogen), Turbidity✓
Lake KanturkLeonAlgal growth, Nutrients (phosphorus, nitrogen)—
Lake KanturkLeonAlgal growth, Nutrients (phosphorus, nitrogen)—
Kanturk LakeLeonAlgal growth, Nutrients (phosphorus, nitrogen)—
Lake ClarkePalm BeachAlgal growth, Impaired biota (cause unknown), Nutrients (phosphorus, nitrogen)—
Alford Arm Tributary LakeLeonOxygen depletion (low DO)—
Ella LakeLakeMercury✓
Lake BryantMarionMercury✓
Georges LakePutnamMercury, pH / acidity✓
Ella LakeLakeMercury✓

Frequently Asked Questions

How many lakes are impaired in Florida?

244 of 2,012 measured Florida lakes (12%) are listed as impaired in the most recent EPA ATTAINS reporting cycle. Of those, 130 are on the federal Clean Water Act §303(d) list and 146 have an approved Total Maximum Daily Load (TMDL) restoration plan.

What does Clean Water Act §303(d) mean?

Section 303(d) of the federal Clean Water Act requires every state to identify waters that don't meet water quality standards even after pollution control measures. Each listed water must then have a Total Maximum Daily Load (TMDL) developed — a plan that caps how much of each pollutant can enter the waterbody. The "303(d) list" is the impaired-waters list. The EPA reviews each state's list every two years.

What are the top causes of impairment in Florida?

The most common causes flagged across Florida's impaired lakes are: Nutrients (phosphorus, nitrogen) (107 lakes); Algal growth (95 lakes); Mercury (83 lakes); Impaired biota (cause unknown) (63 lakes); pH / acidity (42 lakes); Oxygen depletion (low DO) (17 lakes). Mercury is widespread in fish tissue across the upper Midwest from atmospheric deposition. Nutrient impairment (phosphorus, nitrogen) typically reflects agricultural runoff and urban stormwater.

Can I swim in an impaired lake?

It depends on the cause of impairment. A lake impaired for "mercury in fish tissue" is generally safe to swim in — the warning is about long-term consumption of fish. A lake impaired for "pathogens" (E. coli) or "algal growth" may pose a swimming risk and often has a separate beach advisory. Check the cause categories listed for each lake below, and consult your state health department's beach monitoring program for current advisories.

Where does this impairment data come from?

Every impairment record on this page comes from the EPA's ATTAINS (Assessment and TMDL Tracking and Implementation System) public dataset, the federal repository of state-reported water quality assessments. EPA ATTAINS is published as GeoParquet files on the EPA Office of Water S3 bucket and refreshed several times per year. Causes and use-support codes follow EPA's standard taxonomy.

Data source

Impairment data from the EPA ATTAINS (Assessment and TMDL Tracking and Implementation System) public dataset. Assessment unit IDs are matched to LakeQuality lakes by name and proximity; some lakes may not appear here if their ATTAINS name doesn't match our naming convention. For an official query, consult Florida's state water-quality agency.