Nitrate In Drinking Water In North Carolina
What residents of North Carolina 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, North Carolina Division of Water Resources (NC DWR), CDC · Last reviewed: 2025-01-01
Quick Answer
Is nitrate in drinking water a real concern in North Carolina?
Yes — Eastern North Carolina has one of the highest concentrations of concentrated animal feeding operations (CAFOs) in the U.S., and nitrate in private wells in those counties is a documented public health concern.
Is this mostly a public-water issue, a private-well issue, or both?
Primarily private well users in eastern NC counties near hog and poultry operations; public water systems are monitored but generally comply with the nitrate MCL.
What is the main reason residents should care?
Duplin, Sampson, Bladen, and Wayne Counties in eastern NC have a very high density of hog and poultry CAFOs. Spray fields receiving animal waste can allow nitrate to leach into groundwater, where private well users may be exposed.
Key Facts
| EPA Nitrate MCL | 10 mg/L as N |
| Eastern NC CAFO density | One of the highest concentrations of hog and poultry CAFOs in the US |
| Highest-risk counties | Duplin, Sampson, Bladen, Wayne — hog operation spray fields near private wells |
| Testing access | NC county health departments offer private well testing assistance |
| State oversight | NC Division of Water Resources (NC DWR) |
Why This Matters in North Carolina
Eastern North Carolina is home to one of the highest densities of hog and poultry concentrated animal feeding operations (CAFOs) in the United States. Hog lagoons and spray fields — where liquid waste is pumped onto nearby fields — can allow nitrate to move through sandy Coastal Plain soils into shallow aquifers. Private wells in Duplin, Sampson, Bladen, Wayne, and surrounding counties are at elevated risk. NC DEQ's Division of Water Resources monitors public water systems for nitrate compliance; private wells are the owner's responsibility. North Carolina has an active well testing assistance program through county health departments.
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.
North Carolina 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.
Charlotte Water
Charlotte · 1,163,701 served
City of Winston-salem
Clemmons · 388,060 served
City of Durham
Durham · 322,083 served
City of Greensboro
Greensboro · 319,588 served
Town of Cary
Cary · 224,000 served
Fayetteville Public Works Comm
Fayetteville · 215,590 served
Cfpua-wilmington
Wilmington · 198,740 served
Union County Water System
Monroe · 167,554 served
City of Asheville
Asheville · 157,431 served
Davidson Water Inc
Lexington · 153,632 served
How Nitrate Gets Into Drinking Water
Agricultural fertilizer and manure runoff
Nitrogen-based fertilizers and animal waste applied to North Carolina 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 eastern NC hog and poultry operation counties (Duplin, Sampson, Bladen, Wayne) should test annually. Families with infants are at the greatest risk if nitrate levels exceed 10 mg/L as N.
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 North Carolina
- 1
Identify your water utility. Use the ZIP lookup below or browse the North Carolina 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 North Carolina Division of Water Resources (NC DWR)-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
North Carolina 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.