Houston, Texas Water Quality Report

Population: 2,304,580 | Last Updated: 1/14/2024

Overall Water Quality Grade

Based on compliance rates, contaminant levels, and treatment effectiveness

B
78/100
94%
Lead Compliance
96%
Bacterial Compliance
88%
Chemical Compliance
8.3
pH Level

Water Sources

Houston receives its drinking water from multiple sources:

Lake Houston

25%

Surface Water

Reservoir on the San Jacinto River northeast of Houston

Lake Conroe

30%

Surface Water

Reservoir on the West Fork of the San Jacinto River

Trinity River

35%

Surface Water

Water from the Trinity River via Lake Livingston

Local Groundwater

10%

Groundwater

Groundwater from the Gulf Coast Aquifer and Chicot Aquifer

Detected Contaminants

All contaminants listed below are within legal limits, but some may exceed health guidelines.

ContaminantDetected LevelLegal LimitHealth GoalStatusTrend
Total Trihalomethanes (TTHMs)68 ppb80 ppb0 ppbBelow Legal Limit stable
Haloacetic Acids (HAA5)48 ppb60 ppb0 ppbBelow Legal Limit stable
Lead5.2 ppb15 ppb0 ppbBelow Legal Limit stable
Radium2.8 pCi/L5 pCi/L0.43 pCi/LAbove Health Goal stable
Atrazine1.2 ppb3 ppb0.15 ppbAbove Health Goal seasonal

Comparison with Texas State Average

Lead Compliance

Houston
94%
Texas Avg
91%

3.0 points above state average

Bacterial Compliance

Houston
96%
Texas Avg
95%

1.0 points above state average

Chemical Compliance

Houston
88%
Texas Avg
86%

2.0 points above state average

Overall Score

Houston
78%
Texas Avg
76%

2.0 points above state average

Water Quality Trends

Overall water quality score over the past 5 years

76
2019
76
2020
74
2021
77
2022
78
2023

Water quality has improved by 2.0 points since 2019

Contamination History

2017

Hurricane Harvey Impact

Massive flooding from Hurricane Harvey caused temporary water quality concerns and boil water notices in some areas

Resolution:

Emergency chlorination, extensive testing, infrastructure repairs completed

2021

Winter Storm Uri

Severe winter storm caused water main breaks and treatment plant operational challenges

Resolution:

Boil water notice issued and lifted after testing confirmed safety, infrastructure winterization improvements made

Frequently Asked Questions - Houston Water Quality

Is Houston tap water safe to drink?

Yes, Houston's tap water meets all federal and state drinking water standards. The city operates multiple treatment plants and conducts thousands of water quality tests monthly to ensure safety.

Why does Houston water taste different sometimes?

Houston draws water from multiple surface water sources (lakes and rivers) which can vary in taste depending on seasonal factors, rainfall, and which plant serves your area. All sources are treated to meet quality standards.

What are disinfection byproducts and should I be concerned?

Disinfection byproducts (TTHMs and HAA5) form when chlorine reacts with organic matter in water. Houston's levels are below federal limits. The city uses optimized treatment processes to minimize these compounds while maintaining necessary disinfection.

How did Hurricane Harvey affect Houston's water?

While some areas experienced temporary boil water notices, Houston's water system proved resilient. The city has since invested in infrastructure improvements and emergency preparedness to better handle extreme weather events.

Should I filter my Houston tap water?

Houston tap water is safe to drink as-is. However, some residents use filters to improve taste or reduce chlorine. If filtering, use NSF-certified filters and maintain them according to manufacturer instructions.

Nearby Water Utilities

Compare water quality in nearby cities:

Sugar Land, TX

Pasadena, TX

Pearland, TX

The Woodlands, TX

Utility Information

Water Provider

Houston Public Works

Contact Information

Customer Service: 832-395-2700

Emergency: 311

Data Disclaimer

This water quality report is compiled from publicly available data and annual water quality reports. For the most current information, please contact your local water utility or visit their official website. Last updated: 1/14/2024.