Houston Water Quality Guide: Hurricane Flooding Risks
Comprehensive guide to Houston water quality, hurricane and flooding impacts, treatment processes, and safety information.
Environmental Health Research
Health Information Reviewed
Health-related content reviewed by Michael Rodriguez, MSc, Public Health Consultant, to ensure public health recommendations are accurate and appropriate.
Last reviewed: April 2026
Water Source
Houston draws water from two primary sources: surface water from Lake Houston, Lake Conroe, and the Trinity River, and groundwater from the Evangeline and Chicot aquifers. The surface water sources provide the majority of the city's supply, with Lake Houston formed by the Lake Houston Dam on the San Jacinto River. The City of Houston operates one of the largest municipal water systems in the United States, serving 2.2 million people directly plus wholesale customers. Groundwater use has decreased over decades to prevent land subsidence, shifting reliance to surface water sources.
Water Treatment Process
Houston operates multiple surface water treatment plants including the East Water Purification Plant, Southeast Water Purification Plant, and Northeast Water Purification Plant. Treatment includes coagulation and flocculation, sedimentation, filtration, and disinfection. Ozone is used for primary disinfection at some facilities, followed by chloramines for distribution system residual. Groundwater receives disinfection and sometimes additional treatment depending on well characteristics. All water meets Texas Commission on Environmental Quality (TCEQ) and EPA standards before distribution.
Known Issues and Hurricane Vulnerability
Houston's location on the Gulf Coast creates unique water quality challenges, particularly related to extreme weather events and flooding.
- Hurricane flooding can overwhelm infrastructure and affect water quality
- Boil water notices issued during and after major storms
- Surface water quality affected by runoff after heavy rainfall
- Industrial contamination risks in heavily developed watershed
- Disinfection byproducts can increase during high-demand periods
- Aging infrastructure in some older neighborhoods
- Saltwater intrusion concerns in some coastal-area wells
- Combined sewer overflow risks during extreme rainfall
Recent Improvements and Resilience Efforts
Following Hurricane Harvey and other major storms, Houston has invested significantly in water system resilience and infrastructure improvements.
- Hardened critical water infrastructure against flooding
- Invested billions in post-Harvey infrastructure recovery
- Expanded treatment capacity with new facilities
- Upgraded emergency response and notification systems
- Improved backup power at treatment facilities
- Enhanced real-time water quality monitoring
- Replaced aging water mains in priority areas
- Developed comprehensive flood resilience plans
EPA Compliance and Monitoring
Houston's water system maintains compliance with EPA drinking water standards under normal operating conditions. The city conducts extensive testing and publishes annual Consumer Confidence Reports. During major weather events, the city issues precautionary boil water notices when system pressure drops or contamination risk increases. Houston participates in EPA monitoring programs for unregulated contaminants and has expanded testing for PFAS and other emerging contaminants. Real-time monitoring helps detect quality changes quickly.
Note: For the most current water quality data, view the Houston Water Quality Report which includes EPA SDWIS data and contaminant analysis.
Recommendations for Houston Residents
Houston tap water is safe under normal conditions, but residents should be prepared for weather-related disruptions.
- 1Maintain emergency water supplies for hurricane season
- 2Follow boil water notices issued during storms
- 3Sign up for city emergency alerts and notifications
- 4Consider whole-house filtration for comprehensive protection
- 5Carbon filters can improve taste and remove chloramines
- 6Review annual Water Quality Reports from the city
- 7Know how to shut off water supply in emergencies
- 8Report water quality concerns or main breaks promptly
Water Filter Options for Houston
Based on Houston's water quality profile, consider these filtration options:
Activated Carbon Filters
Good for improving taste, removing chlorine/chloramine, and filtering common organic compounds.
Reverse Osmosis Systems
Comprehensive filtration removing 95-99% of contaminants including lead, PFAS, and dissolved solids.
Related Resources
- Houston, Texas Water Quality Report
View current contaminant data and quality scores
- Texas State Water Quality Overview
Compare water quality across Texas cities
- Home Water Testing Guide
How to test your water at home
- Complete Guide to Lead in Drinking Water
Understanding lead risks and mitigation
- How to Choose the Right Water Filter
Filter recommendations by contaminant type
- Water Filter Cost Calculator
Calculate the cost of different filtration options