Nitrate violations in Arizona
210 active public water systems in Arizona had a Nitrate violation in the past three years, 24 of them in the latest quarter of EPA's data. What Nitrate is and why it matters.
Health effects: Methemoglobinemia in infants under 6 months: gut bacteria convert nitrate to nitrite, which blocks oxygen transport in blood. Pregnant women should also take precautions. Chronic adult exposure at elevated levels may increase cancer risk.
Systems with a Nitrate violation
Latest quarter first, then largest first| System | Serves | Status | Rules violated, 3 yr | Unresolved |
|---|---|---|---|---|
|
Hotevilla Village Hotevilla, Hotevilla/bacavi Community Sc · County |
1,601 | 8 | 4 | |
|
Many Farms Community School Bia Many Farms · County |
1,506 | 4 | 1 | |
|
Shungopavi Shungopavi · County |
1,430 | 7 | 3 | |
|
Kayenta Sandstone Housing Kayenta · County |
1,375 | 5 | 1 | |
|
Lord AZ Water 2 Winchester Trails Vernon · Apache County |
1,289 | 4 | 0 | |
|
Chilchinbeto Ntua Chilchinbeto · County |
1,276 | 3 | 1 | |
|
Town of Star Valley Water Department Star Valley · Gila County |
1,157 | 4 | 1 | |
|
Vaya Chin Intertie Vaya Chin, Hickiwan, San Simon Village/s · County |
1,151 | 2 | 0 | |
|
Hopi High School Bia Hopi High School · County |
1,005 | 11 | 4 | |
|
Hawley Lake Homes County |
990 | 4 | 2 | |
|
Chinle High School Chinle High School · County |
975 | 4 | 2 | |
|
Gcnra Lees Ferry Lees Ferry · Coconino County |
890 | 5 | 1 | |
|
Humboldt Water System Humboldt · Yavapai County |
830 | 1 | 0 | |
|
Greasewood Springs Community Boarding School Bia Lower Greasewood · County |
720 | 7 | 3 | |
|
Adaman Mutual Water Company Adaman · Maricopa County |
700 | 8 | 1 | |
|
Ganado Public Schools Ganado · County |
684 | 4 | 1 | |
|
Apple Annies Orchard Willcox · Cochise County |
675 | 3 | 1 | |
|
Apache Burger Travel Center County |
650 | 4 | 1 | |
|
Main Street Market #640 Ehrenberg · La Paz County |
600 | 4 | 0 | |
|
LA Casita Water Company 3 Tucson · Pima County |
598 | 2 | 0 | |
|
St Michael Indian School St. Michaels · County |
585 | 5 | 1 | |
|
Kayenta Community Boarding School Bia Kayenta · County |
500 | 3 | 1 | |
|
Dilcon Community Boarding School Bia Dilcon · County |
473 | 5 | 1 | |
|
Arizona Training Program Coolidge · Pinal County |
470 | 8 | 2 | |
|
Lower Moencopi Spring Source Lower Moencopi · County |
465 | 12 | 3 | |
|
Douglas Border Patrol Station Douglas · Cochise County |
450 | 3 | 0 | |
|
Maricopa Mountain Dwid 1 Stanfield · Pinal County |
450 | 2 | 0 | |
|
Country Club Acres Water INC Wickenburg · Maricopa County |
431 | 4 | 0 | |
|
Kaibab Village Kaibab Village · County |
407 | 4 | 0 | |
|
Payson Water Whispering Pines Payson · Gila County |
403 | 2 | 0 | |
|
Canyon Lake Marina Canyon Lake · Maricopa County |
400 | 3 | 0 | |
|
Kaibeto (upper) Boarding School Bia Kaibeto · County |
400 | 2 | 0 | |
|
Picacho Peak RV Resort Red Rock · Pinal County |
400 | 6 | 1 | |
|
Prescott Pines Camp Prescott · Yavapai County |
400 | 3 | 0 | |
|
Wickenburg Mobil Wickenburg · Yavapai County |
400 | 3 | 0 | |
|
Diamond Grove Mobile Home Estates Tucson · Pima County |
385 | 1 | 0 | |
|
Hickmans Egg Ranch Buckeye · Maricopa County |
376 | 5 | 0 | |
|
Payson Water East Verde Estates Payson · Gila County |
375 | 3 | 0 | |
|
Silverbell Irrigation & Drainage Dist Eloy · Pinal County |
375 | 6 | 0 | |
|
CS Loma Linda Water Company Clifton · Greenlee County |
351 | 6 | 0 | |
|
Federal Correctional Inst Tucson · Pima County |
350 | 9 | 0 | |
|
Rough Rock Community High School Bia Rough Rock · County |
350 | 4 | 2 | |
|
Hacienda del Sol MHP Luke Afb · Maricopa County |
300 | 2 | 1 | |
|
Teec Nos Pos Community Boarding School Bia Teec Nos Pos · County |
300 | 2 | 0 | |
|
Santa Cruz County Fairgrounds Sonoita · Santa Cruz County |
297 | 3 | 1 | |
|
Villa Grande Dwid Eloy · Pinal County |
283 | 7 | 0 | |
|
Silver Creek RV Park Bullhead City · Mohave County |
280 | 6 | 0 | |
|
Usfs Conf Cave Springs Oak Creek Canyon · Coconino County |
280 | 3 | 1 | |
|
Second Mesa Day School Bia County |
255 | 6 | 1 | |
|
Cordes Junction Motel RV Park Cordes Junction · Yavapai County |
250 | 3 | 1 |
About this data
A system is counted once if any of its violations in the past three years involved Nitrate, including monitoring and reporting lapses. Rules violated and status in the table are for the whole system, not Nitrate alone.
Source: the U.S. EPA's Enforcement and Compliance History Online system (ECHO), which publishes the federal Safe Drinking Water Information System. EPA's terms and values are shown as published. The Arizona records are from EPA's data refresh of Oct 7, 2026; EPA refreshes this data quarterly, and states report to EPA with a lag of three to six months, so the newest violations may not appear yet.