Nitrate In Drinking Water In Texas
What residents of Texas need to know about nitrate in drinking water — including how it enters water, which utilities have documented violations, and what steps to take.
Source: EPA SDWIS, Texas Commission on Environmental Quality (TCEQ), CDC · Last reviewed: 2025-01-01
Quick Answer
Is nitrate in drinking water a real concern in Texas?
Yes — Texas has 3 million or more private wells, many in agricultural areas where nitrate is a documented groundwater concern.
Is this mostly a public-water issue, a private-well issue, or both?
Private well users in agricultural regions; public water systems are monitored by TCEQ but private wells are the owner's responsibility.
What is the main reason residents should care?
Texas's agricultural regions — the Panhandle (Ogallala Aquifer zone), Rio Grande Valley, and southeast Texas farming areas — have documented nitrate issues. TCEQ monitors public water supplies; private wells are untested and unregulated unless the owner arranges testing.
Key Facts
| EPA Nitrate MCL | 10 mg/L as N |
| Private wells in TX | Estimated 3 million+ — owner's responsibility to test |
| Agricultural regions | Panhandle (Ogallala Aquifer), Rio Grande Valley, SE Texas |
| Primary source | Fertilizer runoff, feedlot operations, irrigation return flow |
| State oversight | TCEQ (public systems only — private wells unregulated) |
Why This Matters in Texas
Texas has an enormous rural population relying on private groundwater wells. The Texas Panhandle draws from the Ogallala Aquifer, which has documented nitrate issues in some areas from decades of irrigated agriculture and feedlot operations. The Rio Grande Valley's intensive vegetable and citrus farming also contributes to agricultural nitrate loading. TCEQ requires public water systems serving 25 or more people to test for nitrate and comply with the 10 mg/L MCL; however, private well users have no automatic testing requirement and are responsible for testing their own water.
Critical — Infants Under 6 Months
Do not use tap water that exceeds 10 mg/L nitrate-nitrogen to prepare infant formula or feed infants under six months. Boiling will concentrate nitrate — do not boil. Use bottled water or a certified reverse osmosis system (NSF/ANSI 58) until the issue is resolved.
Texas Utilities With Nitrate Violation Records
The utilities listed below have at least one nitrate violation on record in EPA's SDWIS database. Violations may be open or resolved — see individual utility pages for current status and risk level.
San Antonio Water System
San Antonio · 2,113,151 served
City of Arlington
Arlington · 413,955 served
City of Corpus Christi
Corpus Christi · 318,387 served
City of Irving
Irving · 264,546 served
City of Laredo
Laredo · 260,046 served
Amarillo Municipal Water System
Texas · 201,291 served
North Alamo Wsc
Texas · 171,195 served
City of Waco
Texas · 146,241 served
City of League City
Texas · 128,412 served
City of Pearland
Texas · 125,828 served
How Nitrate Gets Into Drinking Water
Agricultural fertilizer and manure runoff
Nitrogen-based fertilizers and animal waste applied to Texas cropland can leach into groundwater or run off into surface water supplies. This is the dominant nitrate pathway in most agricultural regions.
Septic system effluent
Failing or poorly sited septic systems release nitrogen-rich wastewater near drinking water wells. Rural areas with high well density and aging septic infrastructure face elevated risk.
Concentrated animal feeding operations (CAFOs)
Large livestock facilities generate significant waste. Lagoon leaks and overapplication of manure to nearby fields can create localized nitrate hotspots in groundwater.
Natural geological deposits
In some regions, naturally occurring nitrogen compounds in soil and bedrock contribute background nitrate levels to groundwater independent of agricultural activity.
Who Should Pay Closest Attention
Families with infants under six months using formula mixed with well water in agricultural Texas counties face the highest risk. Private well users across the Panhandle, Rio Grande Valley, and southeast Texas farming regions should test their water at least annually.
Households with infants under six months
Pregnant residents
Private well owners in agricultural areas
Households near livestock operations or CAFOs
Rural residents on shallow groundwater wells
Households with older or failing septic systems nearby
How to Check Your Situation in Texas
- 1
Identify your water utility. Use the ZIP lookup below or browse the Texas utility directory on this site.
- 2
Read your utility's page on this site to see its current risk level and any open nitrate violations.
- 3
Review your utility's most recent Consumer Confidence Report (CCR) — mailed annually or available on the utility's website. It must disclose any MCL exceedances.
- 4
If you are on a private well, arrange testing at a Texas Commission on Environmental Quality (TCEQ)-certified lab. Your state health department maintains a list of certified labs. Annual testing is recommended in agricultural areas.
- 5
If you have an infant under six months, use bottled water or a certified RO system (NSF/ANSI 58) immediately as a precautionary measure — do not wait for test results if you are in a high-risk area.
- 6
If your utility issues a nitrate exceedance notice, follow their guidance and do not use tap water for infants until the issue is resolved.
Treatment Options
Carbon filters and boiling do not remove nitrate. Only the options below are effective.
NSF/ANSI Standard 58 — Reverse Osmosis
RO systems certified to NSF/ANSI 58 reduce nitrate by 85–95% at the point of use. Under-sink installation required. The most practical residential option for nitrate concerns.
Distillation
Distillation units effectively remove nitrate along with most other dissolved contaminants. Suitable for drinking and cooking water — not whole-house use.
Anion Exchange
Ion exchange systems designed for nitrate removal exchange nitrate ions for chloride on a resin bed. Effective as a point-of-entry system; requires periodic regeneration and monitoring.
Carbon filters do NOT remove nitrate
Standard pitcher filters, faucet filters, and under-sink carbon units — including those certified NSF/ANSI 42 or 53 — do not remove nitrate. Do not use these for nitrate reduction.
Frequently Asked Questions
Related Pages
Nitrate — National Overview
All U.S. utilities with nitrate records
Texas State Overview
All utilities and water quality data
Lead in Drinking Water
A separate but common concern
Reverse Osmosis Guide
Removes 85–95% of nitrate
Well Water Guide
Private well testing and safety
All Contaminants
Complete reference library
Data Sources & Provenance
All data on this page is sourced from official U.S. government or public datasets.
Find Your Utility
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Texas Commission on Environmental Quality (TCEQ) ↗