Lake Mexia
Limestone County, Texas1,009 acresView mapDirections
TCEQ publishes the water-quality measurements for Lake Mexia. Here is what has been measured.
- Hypereutrophic
- 31 ft max depth
- Limited data
Lake Mexia in Limestone County, Texas has water-quality measurements published by TCEQ, shown here as reported. Water clarity: 1.1 ft visibility. Phosphorus: 170 µg/L. Chlorophyll-a (algae): 50.7 µg/L. Surface area: 1009 acres.
Lake Mexia is a 1,009-acre highly nutrient-loaded hypereutrophic lake in Limestone County, Texas with an estimated average depth of about 31 feet. Water clarity is declining over recent sampling years. Compared to the 1 other monitored lakes in Limestone County, Lake Mexia ranks #2 for water quality.
Source: EPA Water Quality Portal sampling records, TCEQ, last sampled 2026-01-13. Methodology: how these readings are compared.
Lake Mexia covers about 1,000 acres in Limestone County. Vrbo is where to look for cabins and lake homes around Lake Mexia, and Booking.com and Expedia search hotels near the lake for your dates.
What Lake Mexia is good for
From access and monitoring records, not editorial picks.
- Big water1,009 acres
Swimming conditions
Readings onlyLimited data
Based on clarity and algae readings from past sampling — there is no live water temperature and a current cyanobacteria reading for this lake. Check your state or county health department before you swim.
Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
Whether Lake Mexia is safe to swim in today is a call for the Texas Commission on Environmental Quality and the county health department, who post current advisories. LakeQuality does not issue swimming clearances.
Water quality measurements for Lake Mexia
These are the measurements TCEQ publishes for Lake Mexia, shown as reported. The condition class beside each reading is the EPA National Lakes Assessment class for this lake’s ecoregion.
Very murky, less than 1.1 ft of visibility. Phosphorus 170 µg/L. Chlorophyll-a 50.7 µg/L. TSI 74.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | 1.1ft | Measured, not scored How deep a black-and-white disk stays visible from the surface. Higher is clearer. |
| Total phosphorus | 170µg/L | Poor GoodFairPoor |
| Chlorophyll-a (algae) | 50.7µg/L | Poor GoodFairPoor |
| Trophic state (TSI)Carlson's 0–100 index of how much algae a lake can support, from clarity, phosphorus and chlorophyll-a. | 74 | Hypereutrophic OligotrophicMesotrophicEutrophicHypereutrophic |
Very high nutrients, dense algae, poor clarity
Ask about Lake Mexia
Answers come straight from the public measurements and survey records on this page.
→ Lake Mexia water level: the live USGS gauge reading
Lake Details
Max depth
~31 ft est.
Surface area
1,009 acres
Depth marked “est.” is a modeled maximum from GLOBathy (Khazaei et al. 2022, CC0), not a measured survey. Texas has not published bathymetry for Lake Mexia.
Lake Size & Watershed
Watershed (drainage) area
195 sq mi
HydroLAKES / HydroSHEDS
Shoreline
11.9 mi
HydroLAKES / HydroSHEDS
Elevation
453 ft
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS). Mean depth here is modelled, not surveyed — HydroLAKES v1.0 estimates lake depth from surrounding terrain rather than from soundings. Treat it as an approximation, and prefer a state bathymetric survey where one exists.
Stays via Stay22
Stays near Lake Mexia
Compare lakeside cabins, hotels, and vacation rentals near Lake Mexia in Limestone County, Texas — live availability and prices for your trip. Switch the map to Satellite to see the lake and how close each stay is to the water. The water-quality readings cover nutrients and algae, not lodging. Cabins and rentals around Lake Mexia are listed below.
Top-rated places to stay near Lake Mexia
Prices for Oct 23–25, 4 adults. Change dates on the map below.
Availability and prices from Stay22 partners (Booking.com, Vrbo, Expedia). We may earn a commission from bookings, at no extra cost to you.
Planning a whole trip? See where to stay at Texas’s top lakes →
Follow Lake Mexia’s readings
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Fishing Lake Mexia
Water Quality Trend: Stable
Based on 5 years of monitoring (2021–2025).
Water clarity
Worsening5 years
Phosphorus
Stable+0.93 µg/L/yr4 years
Chlorophyll-a
Improving-2.83 µg/L/yr4 years
Reservoir Info (USACE NID)
Lake Mexia is a man-made reservoir impounded by the Bistone Dam (completed 1961), built primarily for water supply on the Navasota River; earth-type dam, 50 ft tall and 1,645 ft long.
- Surface area
- 1,009 ac
- Normal storage
- 4,687 ac-ft
- Max storage
- 44,321 ac-ft
- Drainage area
- 198 sq mi
- Hazard class
- High
- Owner
- BISTONE MWS DISTRICT
All listed purposes: Water Supply;Other;Recreation.
Source: USACE National Inventory of Dams, NID ID TX01061 · Operator website · Matched by proximity (0.34 km)
Nearby Lakes in Limestone County
Frequently asked questions about Lake Mexia
Where is Lake Mexia?
- Lake Mexia is a lake in Limestone County, Texas. Its water-quality measurements are published by TCEQ and shown on this page as reported.
What is the water quality of Lake Mexia?
- Lake Mexia in Limestone County, Texas has water-quality measurements published by TCEQ, shown here as reported. Water clarity: 1.1 ft visibility. Phosphorus: 170 µg/L. Chlorophyll-a (algae): 50.7 µg/L. Surface area: 1009 acres.
Is Lake Mexia safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
How deep is Lake Mexia?
- No published bathymetric survey covers Lake Mexia, so its depth has not been measured. The HydroLAKES global model estimates an average depth of about 31 feet, but that is a modelled estimate derived from surrounding terrain rather than a measurement on the water, so treat it as approximate. The lake covers 1009 acres.
Explore Lake Mexia across LakeQuality
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Where this data comes from
61 measurements from 1 monitoring station, 2020–2026. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Texas Commission on Environmental Quality
TCEQMAIN61 samples · 2020–2026
Monitoring station identifiers (1)
EPA condition classes from the National Lakes Assessment (EPA 841-R-24-006, Table 6-3), applied by ecoregion. See where the data comes from and data sources.
Other records on this page
Lake size & watershed from HydroLAKES (HydroSHEDS)