What Houston Residents Should Know
Houston's drinking water system is one of the largest in the United States, serving over 2.3 million residents. The city's primary water sources are surface water from the Trinity River, Lake Houston, and Lake Conroe, supplemented by groundwater from the Gulf Coast Aquifer.
While Houston's water meets federal and state standards at treatment facilities, there are several challenges that affect water quality. The region's susceptibility to flooding can temporarily impact water treatment, the city's aging infrastructure includes areas with lead service lines and pipes installed before the 1986 lead ban, and certain neighborhoods face higher risks due to infrastructure age and maintenance issues.
Recent sampling has shown that some areas, particularly in older neighborhoods, have detectable levels of lead, disinfection byproducts, and in some cases, industrial contaminants. Houston Public Works has initiated programs to address these issues, but residents in certain areas should take precautions.
Key Contaminants Found
These contaminants have been detected in Houston's water supply at levels that may be concerning for some residents.
Lead
Near Limit in Some AreasSource: Lead service lines, lead solder in plumbing, and older fixtures and faucets (especially in pre-1986 buildings)
Health Effects: Developmental delays in children, learning disabilities, reduced IQ, kidney problems, high blood pressure in adults
Houston Levels: Average 5.2 ppb (90th percentile), with 6% of samples exceeding the EPA action level of 15 ppb
EPA Limit: Action level 15 ppb, but no safe level exists
Trihalomethanes (TTHMs)
Exceeds in Some AreasSource: Byproducts formed when chlorine used to disinfect water reacts with organic matter
Health Effects: Potential increased risk of cancer with long-term exposure, liver, kidney, and central nervous system problems
Houston Levels: 65-85 ppb in some areas, particularly after flooding events
EPA Limit: 80 ppb
Arsenic
Near Limit in Some AreasSource: Erosion of natural deposits, runoff from orchards, electronic production wastes
Health Effects: Skin damage, circulatory problems, increased risk of cancer
Houston Levels: 3-8 ppb in some groundwater-supplied areas
EPA Limit: 10 ppb
PFAS ("Forever Chemicals")
Low LevelsSource: Industrial discharges, firefighting foam, consumer products
Health Effects: Increased cholesterol, changes in liver function, decreased vaccine response in children, increased risk of certain cancers
Houston Levels: 2.5 ppt (combined PFOA and PFOS), detected in some areas
EPA Limit: 4 ppt for PFOA and PFOS
Neighborhood Variations
Water quality can vary significantly across Houston's neighborhoods, primarily due to differences in infrastructure age, pipe materials, and proximity to industrial areas.
Risk Areas by Neighborhood
| Neighborhood | Risk Level | Average Lead (ppb) | Buildings Pre-1986 | Lead Service Lines |
|---|---|---|---|---|
| Fifth Ward | High | 8.5 | 76% | Very High |
| Third Ward | High | 7.9 | 72% | High |
| Heights | Medium | 5.8 | 68% | Medium |
| Montrose | Medium | 5.1 | 62% | Medium |
| Spring Branch | Medium | 4.8 | 55% | Medium |
| The Woodlands | Low | 2.2 | 12% | Very Low |
Data based on Houston Public Works sampling and U.S. Census housing statistics.
Recommended Action Steps
Based on Houston's water quality data, we recommend these actions to protect yourself and your family.
Test Your Water
Request a water quality test kit from Houston Public Works or use a certified laboratory to test your home's water for lead and other contaminants, especially if you live in an older neighborhood.
Flush Your Pipes
If your water has been sitting for several hours, run cold water for 30-60 seconds or until it becomes cold before using it for drinking or cooking. For homes with lead service lines, run water for 3-5 minutes.
Use Cold Water for Consumption
Always use cold water for drinking, cooking, and preparing baby formula. Hot water can contain higher levels of lead and other contaminants as it dissolves them more readily from pipes.
Consider a Water Filter
If you live in a high-risk area or have concerns about your water quality, use a filter certified to remove lead (NSF/ANSI Standard 53) and other contaminants specific to your area. Replace filter cartridges according to manufacturer recommendations.
Check Your Plumbing
Determine if your home has lead pipes, fixtures, or solder by consulting with a licensed plumber. Homes built before 1986 are more likely to have plumbing components containing lead.
View Houston Lead Pipe MapBe Alert After Floods
After major flooding events in the Houston area, be particularly vigilant about water quality. Follow any boil water notices and consider using bottled water until authorities confirm the water is safe.
Want to know your personal water quality risk?
Answer a few quick questions about your home and get a personalized water quality assessment and action plan.
Take the Assessment