Houston Water Quality 2026
Reviewed by Joe Letorney, 30-year water treatment expert · Former WQA Certified Water Treatment Specialist (CWS), Level VI
Houston Water · Trinity River / Lake Houston source · 2024–2025 data
Source: Houston Water CCR 2024 · EPA SDWIS · EPA UCMR5 · EWG Tap Water Database
Houston has some of the most contaminated tap water of any major US city. Significant PFAS contamination from industrial sources, elevated arsenic, high disinfection byproducts, radium, and very high sodium. A reverse osmosis filter is strongly recommended.
WaterCheckup Safety Score — an independent index from EPA public data and our formula. Not your utility’s official water quality rating, an EPA compliance grade, or a test of water at your tap. How we score →
Houston's water comes primarily from surface sources — the Trinity and San Jacinto rivers — which are more vulnerable to agricultural runoff, industrial discharge, and storm events than groundwater systems. The city's public water system serves one of the largest metro populations in the country, treating millions of gallons daily with chloramine.
Houston's industrial corridor is the elephant in the room for PFAS. Facilities that used aqueous firefighting foam and fluorochemical processes have left a fingerprint in Gulf Coast watersheds. UCMR5 data showing PFAS above EPA limits is not an abstract lab result — it is the reason I do not recommend standard pitcher filters for Houston families asking about "forever chemicals."
Trihalomethanes and haloacetic acids are the other Houston headline. Warm surface water plus organic load equals more DBPs when chlorine or chloramine is applied. RO at the drinking tap removes both classes of contaminants; whole-home carbon can reduce DBPs for shower exposure if that is a priority. Always match the filter to what your ZIP report actually flags.
See best water filters for lead removal and what filters remove PFAS.
Houstonwater may meet federal EPA limits while still showing contaminants above independent health guidelines (EWG, state advisories). EPA MCLs are often set on treatment feasibility — not a "zero risk" threshold. Compare levels below to health guidelines and state/U.S. utility averages, then see which filter technologies address your profile.
EPA UCMR5 PFAS plus utility/EWG averages with national and state benchmarks. Run a ZIP report for SDWIS samples at your address.
From Houston Water CCR 2024
Removes with: RO · Ion exchange
EWG health guideline: 700 ppb
EWG Tap Water Atlas utility average (2021–2023) · U.S. utility avg (EWG Atlas sample): 43.45 ppb · TX utility avg: 86.41 ppb
Removes with: RO · Carbon · Ion exchange
EWG Tap Water Atlas utility average (2021–2023) · U.S. utility avg (EWG Atlas sample): 33.94 ppb · TX utility avg: 66.34 ppb
Removes with: RO · Carbon
PFAS (“forever chemicals”) persist in the body. NSF 58 reverse osmosis or NSF P473-certified filters remove PFAS at the tap — standard pitchers do not.
Removes with: RO
EWG Tap Water Atlas utility average (2021–2023) · U.S. utility avg (EWG Atlas sample): 23.64 ppb · TX utility avg: 25.38 ppb
Removes with: RO · Carbon
EWG Tap Water Atlas utility average (2021–2023) · U.S. utility avg (EWG Atlas sample): 18.30 ppb · TX utility avg: 18.30 ppb
Removes with: RO · Carbon
Can impair thyroid function — most concerning during pregnancy and childhood.
Removes with: RO · Carbon
EWG health guideline: 0.15 ppb
EWG Tap Water Atlas utility average (2021–2023) · U.S. utility avg (EWG Atlas sample): 30.97 ppb · TX utility avg: 29.72 ppb
Removes with: RO · Carbon
EWG Tap Water Atlas utility average (2021–2023) · U.S. utility avg (EWG Atlas sample): 35.15 ppb · TX utility avg: 67.04 ppb
Removes with: RO · Carbon
EWG health guideline: 0.06 ppb (HAA5)
EWG Tap Water Atlas utility average (2021–2023) · U.S. utility avg (EWG Atlas sample): 21.57 ppb · TX utility avg: 14.51 ppb
Removes with: RO · Carbon
EWG Tap Water Atlas utility average (2021–2023) · U.S. utility avg (EWG Atlas sample): 7.10 ppb · TX utility avg: 7.10 ppb
Removes with: RO · Carbon
EWG health guideline: 0.2 ppb
Disinfection byproduct linked to bladder cancer and possible reproductive effects.
Removes with: RO · Carbon
EWG Tap Water Atlas utility average (2021–2023) · U.S. utility avg (EWG Atlas sample): 17.82 ppb · TX utility avg: 7.73 ppb
Removes with: RO · Carbon
EWG Tap Water Atlas utility average (2021–2023) · U.S. utility avg (EWG Atlas sample): 23.44 ppb · TX utility avg: 23.77 ppb
Removes with: RO · Carbon
PFAS (“forever chemicals”) persist in the body. NSF 58 reverse osmosis or NSF P473-certified filters remove PFAS at the tap — standard pitchers do not.
Removes with: RO · Carbon
EWG health guideline: 100 ppb
Long-term exposure at high levels may affect the nervous system. Staining and taste issues at lower levels.
Removes with: RO · Carbon
PFAS (“forever chemicals”) persist in the body. NSF 58 reverse osmosis or NSF P473-certified filters remove PFAS at the tap — standard pitchers do not.
Removes with: RO · Carbon
EWG health guideline: 0.06 ppb
THM component linked to cancer and reproductive harm with long-term exposure.
Removes with: RO · Carbon
U.S. and state averages from EWG Tap Water Atlas utilities in our database. For your exact tap, use a ZIP report — home plumbing can differ from utility averages.
Reference matrix — not specific brands. NSF-certified carbon blocks, reverse osmosis (NSF 58), and ion-exchange softeners address different contaminants. Product picks below match this profile.
Houstonutility data is a strong baseline — but lead often comes from your home's pipes, and PFAS can vary by neighborhood. Choose certified lab testing for certainty, or skip straight to NSF-certified filters matched to this profile.
SimpleLab Tap Score mail-in panels test PFAS, lead, nitrates, bacteria, and 100+ contaminants at your kitchen tap. Results in about a week — then pick filtration with real numbers, not guesses.
Tap Score City Test — from $89 →Accredited labs · Best if you have old plumbing, pregnancy, or want proof before installing RO
Get NSF 58 / NSF 53 picks matched to Houston's PFAS, lead, and disinfection byproduct profile — reviewed by a 30-year water treatment expert.
Take the 3-question filter quiz →Best when contaminants are already flagged above and you want the right RO or pitcher today
Houston's PFAS contamination is driven by its massive petrochemical and industrial complex. The Houston Ship Channel area has dozens of facilities that historically used PFAS-containing products including firefighting foam. This industrial PFAS has contaminated the Trinity River watershed that feeds Houston's water supply.
At 22.4 ppt total PFAS, Houston exceeds the EPA's 2024 limits significantly. Only reverse osmosis or NSF 58-certified filters reliably remove PFAS. Standard pitcher filters, Brita, and PUR do not remove PFAS.
Houston water meets all federal EPA legal standards — there are no open violations. However, PFAS has been detected at 22.4 ppt, which exceeds the EPA's 2024 limit of 4 ppt for PFOA/PFOS individually. A reverse osmosis filter is strongly recommended for Houston households.
Yes — Houston has among the highest PFAS levels of any major US city at 22.4 ppt total. Industrial contamination from the Houston Ship Channel area is the primary source. Only reverse osmosis or NSF 58-certified filters reliably remove PFAS.
Yes — Houston water contains arsenic at 5.1 ppb, naturally occurring from the Trinity River watershed. This is below the EPA limit of 10 ppb but well above the EWG health guideline of 0.004 ppb. Reverse osmosis removes arsenic.
Houston's surface water source (Trinity River / Lake Houston) has high organic content, which leads to elevated disinfection byproducts (TTHMs and HAAs) when treated with chlorine. These byproducts affect taste and odor. An activated carbon or RO filter significantly improves taste.
Given Houston's high PFAS, arsenic, TTHMs, and elevated sodium, a reverse osmosis system is the best choice. The Waterdrop G3P600 or Aquasana SmartFlow RO handle Houston's full contaminant profile. For renters, the Clearly Filtered pitcher removes PFAS without installation.
Free · No account · Any US ZIP code
Reviewed by Joe Letorney, 30-year water treatment expert · Former WQA Certified Water Treatment Specialist (CWS), Level VI
Data sourced from Houston Water CCR 2024, EPA SDWIS, EPA UCMR5, and EWG Tap Water Database. WaterCheckup is not affiliated with Houston Water or the EPA. Some filter links are affiliate links.