Houston – Texas
Houston manages a vast water system that serves over 2.2 million residents, drawing from both surface and groundwater sources. The city’s drinking water technically meets federal safety standards, but contains contaminants that raise concerns among health experts. While the City of Houston works diligently to maintain water quality, aging infrastructure and environmental factors continue to present challenges.
Houston Public Works has achieved a “Superior Water Supply System” rating from the Texas Commission on Environmental Quality (TCEQ), the highest water quality rating awarded to a water utility. Nevertheless, recent testing has identified contaminants such as arsenic, lead, and PFAS in some areas, prompting many residents to use filtration systems for additional protection.
Houston Water Quality: Current Status (2024-2025)
Latest Testing Results
- Compliance Status: Houston’s water system currently meets all federal and state safety standards according to the U.S. EPA’s latest quarterly assessment (April-June 2024). However, meeting legal standards doesn’t necessarily mean the water meets the latest health guidelines.
- Arsenic Levels: The highest detected concentration of arsenic in Houston’s main system was reported at 8 parts per billion (ppb), with an average of 2.3 ppb. While within EPA’s regulated threshold of 10 ppb, health experts recommend levels closer to zero.
- Lead Concerns: Recent testing found that 10% of samples analyzed for lead in Houston were 4 parts per billion. While this is within federal compliance, the EPA and CDC acknowledge there is no safe level of lead for children.
Water Sources and Treatment
- Surface Water: About 86% of Houston’s water supply comes from surface water sources: the Trinity River flowing into Lake Livingston, and the San Jacinto River feeding Lake Conroe and Lake Houston.
- Groundwater: The remaining 14% of the city’s water supply comes from deep underground wells drilled into the Evangeline and Chicot aquifers.
- Treatment Process: Houston employs a multi-step water treatment process including filtration, disinfection, and chemical treatment. A high-tech chemical injection facility is located where water from the various sources combines before distribution.
Water Quality Monitoring
- Real-time Systems: The Source Water Protection Group uses real-time monitoring systems at numerous locations to detect potential contaminants in raw water resources.
- Regulatory Oversight: Houston’s water is monitored under the guidelines of the Safe Drinking Water Act, with the Texas Commission on Environmental Quality (TCEQ) providing state-level oversight.
- Independent Testing: Environmental groups including the Environmental Working Group (EWG) have conducted independent testing that identified concerning levels of contaminants that exceed their health-based guidelines.
Emerging Concerns
Multiple studies have identified PFAS (per- and polyfluoroalkyl substances) in some Houston water sources. These “forever chemicals” are used in everything from non-stick cookware to firefighting foam and have been linked to various health issues. The city reports that detectable PFAS levels remain below the EPA’s maximum residue limits.
Recommendations for Houston Residents
Use Water Filters
Consider using NSF-certified water filters designed to remove specific contaminants of concern. For comprehensive protection against arsenic, lead, and PFAS, look for filters certified under NSF Standard 53 and 58.
Test Your Home’s Water
Consider having your tap water tested, especially if you live in an older home or area with known water quality issues. Many private laboratories offer comprehensive water testing services.
Update Plumbing Fixtures
If you live in a home built before 1986, consider replacing older faucets and fixtures which may contain lead. Look for fixtures labeled “lead-free” that comply with current standards.
Flush Your Pipes
If water hasn’t been used for several hours, run cold water for 1-2 minutes before using it for drinking or cooking. This helps flush out water that may have absorbed lead or other contaminants from pipes.
Stay Informed
Review Houston’s annual Consumer Confidence Report on water quality, published each year on the Houston Public Works website. You can also check the Environmental Working Group’s Tap Water Database for independent assessments.
Frequently Asked Questions
Is Houston’s tap water safe to drink?
Legally, Houston’s tap water meets all federal and state safety standards. However, these standards haven’t been updated in many years, and some contaminants are present at levels that health experts consider concerning. For maximum safety, especially for vulnerable populations like children, pregnant women, and those with compromised immune systems, using a quality water filter is recommended.
Why is Houston water sometimes discolored?
Discoloration in Houston tap water can occur for several reasons. Yellow or brown water is often caused by sediment, aging pipes, or oxidized iron in the water system. While usually not harmful, it’s unappealing and may indicate maintenance issues in the water distribution network. If you experience persistent discoloration, report it to Houston Public Works at 311 and consider using filtered water until the issue is resolved.
What type of water filter is best for Houston water?
For Houston water, the best filters address the specific contaminants of concern in our area. Look for NSF-certified filters that remove lead (NSF Standard 53), arsenic (typically require reverse osmosis), and PFAS (NSF P473 or reverse osmosis systems). Many households benefit from a multi-stage approach: point-of-use filters for drinking water (under-sink reverse osmosis or countertop filters) and whole-house filters to address chlorine, sediment, and hard water issues throughout the home.
Does Houston add fluoride to the water?
Yes, Houston adds fluoride to its drinking water as a public health measure to help prevent tooth decay. The level is maintained at approximately 0.7 milligrams per liter (mg/L), which is the optimal level recommended by the U.S. Public Health Service. This practice is endorsed by major health organizations, though some residents prefer to use filters that can remove fluoride if they have concerns about its addition to the water supply.
Contaminants of Concern
Arsenic
Source: Naturally occurring in groundwater; can also come from industrial and agricultural runoff
Health Effects: Linked to skin damage, circulatory problems, and increased cancer risk with long-term exposure
Current Levels: Average of 2.3 ppb with peaks up to 8 ppb EPA Limit: 10 ppb, though health experts recommend closer to zero
PFAS Chemicals
Source: Industrial applications, firefighting foam, non-stick cookware, stain-resistant products, and other consumer goods
Health Effects: Potential links to reduced vaccine response, developmental effects, liver damage, thyroid disease, and increased cancer risk
Current Status: Present in Houston water at varying levels, with some areas showing higher concentrations, particularly near industrial sites and the San Jacinto River
Lead
Source: Primarily from older lead service lines, lead solder, and plumbing fixtures in homes built before 1986
Health Effects: Developmental delays, learning difficulties, behavioral problems in children; kidney problems and high blood pressure in adults
Current Levels: 90th percentile tests at about 4 ppb EPA Limit: 15 ppb action level, though no amount of lead is considered safe for children
Disinfection Byproducts
Source: Formed when chlorine used to disinfect water reacts with naturally occurring organic matter
Health Effects: Potential increased risk of bladder cancer and adverse reproductive outcomes with long-term exposure
Current Status: Present at varying levels throughout Houston’s water system, with some areas showing higher concentrations than health experts recommend