Moderate–High RiskAgricultural Contaminant

Nitrate In Drinking Water In Missouri

What residents of Missouri 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, Missouri Department of Natural Resources (MDNR), CDC · Last reviewed: 2025-01-01

Quick Answer

Is nitrate in drinking water a real concern in Missouri?

Yes — Missouri's agricultural regions and its extensive karst geology in the Ozarks create documented nitrate concerns in private wells and some public systems.

Is this mostly a public-water issue, a private-well issue, or both?

Primarily private well users in agricultural and karst-terrain counties; public water systems drawing from springs in the Ozarks also require vigilance given the karst's rapid contamination pathways.

What is the main reason residents should care?

Missouri has significant corn, soybean, hog, and cattle production. The Ozark karst geology creates fast underground pathways for agricultural and septic nitrate to reach groundwater — including springs that serve some rural public water systems.

Key Facts

EPA Nitrate MCL10 mg/L as N
Ozark karstCave and spring systems create fast underground pathways for agricultural nitrate
Agricultural sourcesCorn, soybeans, hogs, and cattle across north and west Missouri
Spring-fed systemsSome Missouri rural water systems draw from springs — require nitrate monitoring
State oversightMissouri Department of Natural Resources (MDNR)

Why This Matters in Missouri

Missouri is a major agricultural state, producing significant corn, soybeans, hogs, and cattle. The Missouri River basin in north and west Missouri has intensive row crop farming. The Ozark Plateau in south-central Missouri overlies karst limestone, and the state has extensive cave and spring systems — including the headwaters of large springs used by some public water systems. Agricultural and septic nitrogen entering sinkholes or karst features can travel underground quickly and emerge in springs used for drinking water. MDNR enforces nitrate standards for public systems and provides private well testing guidance. Some Missouri community water systems draw from springs, requiring monitoring for agricultural nitrate.

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.

Missouri 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.

How Nitrate Gets Into Drinking Water

Agricultural fertilizer and manure runoff

Nitrogen-based fertilizers and animal waste applied to Missouri 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

Private well users in Missouri's north and west agricultural regions and in Ozark karst counties should test for nitrate annually. Residents served by spring-fed rural water systems in the Ozarks should check their CCR for recent nitrate monitoring results.

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 Missouri

  1. 1

    Identify your water utility. Use the ZIP lookup below or browse the Missouri utility directory on this site.

  2. 2

    Read your utility's page on this site to see its current risk level and any open nitrate violations.

  3. 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. 4

    If you are on a private well, arrange testing at a Missouri Department of Natural Resources (MDNR)-certified lab. Your state health department maintains a list of certified labs. Annual testing is recommended in agricultural areas.

  5. 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. 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.

See: Reverse Osmosis guide

Frequently Asked Questions

Related Pages

Data Sources & Provenance

All data on this page is sourced from official U.S. government or public datasets.

EPA — Nitrate in Drinking WaterView source
CDC — Methemoglobinemia (Nitrate)View source
EPA SDWIS — Violation and Compliance DataView source
USGS — Nitrate in GroundwaterView source
EPA — Private Wells and NitrateView source
Last updated: 2025-01-01
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