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Impaired Lakes in Texas

33 of 129 graded Texas lakes (26%) are officially listed as impaired under Clean Water Act §303(d) in the most recent EPA ATTAINS reporting cycle.

Top Causes of Impairment in Texas

12
Algal growth
9
Mercury
7
pH / acidity
5
Dioxins
4
Salinity / chlorides
4
Oxygen depletion (low DO)
3
PCBs
1
Total toxics

Reading the Texas impairment landscape

Texas reports 33 impaired lakes — 26% of the state's 129 tracked water bodies. That share is high enough to make impairment a meaningful planning concern: roughly one in four lakes carries at least one §303(d) listing for a pollutant exceeding standards. The list below isn't a niche concern — it's a significant chunk of the state's surface-water inventory.

The leading impairment cause in Texas is Algal growth. Each impairment category carries its own use-restriction implications — some affect fish consumption, some affect swimming, some affect aquatic-life habitat. Click through to the specific lake records below for the pollutant list and the TMDL (Total Maximum Daily Load) status, which determines whether a cleanup plan is in place.

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 Texas submission to the EPA Assessment, Total Maximum Daily Load Tracking and Implementation System (ATTAINS) dataset.

All 33 EPA-Listed Impaired Lakes in Texas

LakeCountyGradeCausesTMDL
Lake MeredithHutchinsonAMercury, Salinity / chlorides
Lake Daingerfield HeadwatersMorrisAMercury
Lake Alan HenryGarzaAMercury
Lake Sweetwater Mid LakeNolanBSalinity / chlorides
Lynchburg ReservoirHarrisCDioxins, PCBs
Lake ColemanColemanCAlgal growth
B A Steinhagen ReservoirJasperCDioxins, Mercury
Houston County LakeHoustonCAlgal growth
Sam Rayburn ReservoirSan AugustineCAlgal growth, Dioxins, Mercury
Lake Tyler ESmithCAlgal growth
Upper Pat Mayse ReservoirLamarCAlgal growth
Pat Mayse ReservoirLamarCAlgal growth
Livingston ReservoirPolkDDioxins, PCBs
White River LakeCrosbyDSalinity / chlorides
Lake GrahamYoungDAlgal growth
Shallow Prong LakeJeffersonDOxygen depletion (low DO)
Lake PalestineSmithFpH / acidity
Lake Crook Mid LakeLamarFAlgal growth
Lake O the Pines Mid LakeMarionFpH / acidity
Lake Cypress Springs Mid LakeFranklinFAlgal growth, pH / acidity
Pat Cleburne ReservoirJohnsonFAlgal growth
Upper Lake PalestineSmithFpH / acidity
Lake OpinesMarionFpH / acidity
Lake Somerville Mid LakeBurlesonFpH / acidity
Greenbelt LakeDonleyNRAlgal growth
Lake KempBaylorNRAlgal growth
Canyon Lake HeadwatersComalNRMercury
Ellison Creek ReservoirMorrisNRDioxins, PCBs, Total toxics
Canyon LakeComalNRMercury
Lake MackenzieBriscoeNRSalinity / chlorides
Rita Blanca LakeHartleyNROxygen depletion (low DO), pH / acidity
Clinton LakeMarionNRMercury, Oxygen depletion (low DO)
Caddo Lake Dwight Shellmans HomeMarionNRMercury, Oxygen depletion (low DO)

Frequently Asked Questions

How many lakes are impaired in Texas?

33 of 129 graded Texas lakes (26%) are listed as impaired in the most recent EPA ATTAINS reporting cycle. Of those, 33 are on the federal Clean Water Act §303(d) list and 0 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 Texas?

The most common causes flagged across Texas's impaired lakes are: Algal growth (12 lakes); Mercury (9 lakes); pH / acidity (7 lakes); Dioxins (5 lakes); Salinity / chlorides (4 lakes); Oxygen depletion (low DO) (4 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 Texas's state water-quality agency.