Blue Hole Water Quality Test Results
For primary contact recreation, the geometric mean criterion for E. coli is 126 per 100mL. In addition, the single sample criterion for E. coli is 399 per 100 mL. “Primary contact recreation” refers to activities where people come into direct contact with water, like swimming or wading.
These standards are set by the Texas Commission on Environmental Quality. More info here – Texas Surface Water Quality Standards
2025 Water Quality Results (E. coli)
June 11, 2025 * low visibility in water and high result due to runoff from rain resulted in closure until 6/18/25
June 16, 2025 * bacteria result is back to a safe range for swimming – swimming resumed two days later 6/18/25
June 17, 2025 * another test was taken for good measure – bacteria levels are dropping back to a normal range
2024 Water Quality Results (E. coli)
May 30, 2024 *higher than usual result due to runoff from 2″+ of rain* – still within safe parameters
June 3, 2024 *a retest was taken after reopening, levels are back down to our usual low result range*
2023 Water Quality Results (E. coli)
| May 3, 2023 | July 5, 2023 |