Revised Total Coliform Rule (RTCR) violations in Arizona
493 active public water systems in Arizona had a Revised Total Coliform Rule (RTCR) violation in the past three years, 204 of them still unresolved. What Revised Total Coliform Rule (RTCR) is and why it matters.
Systems with a Revised Total Coliform Rule (RTCR) violation
Unresolved first, then largest first| System | Serves | Status | Rules violated, 3 yr | Unresolved |
|---|---|---|---|---|
|
Gilbert, Town of Gilbert · Maricopa County |
247,600 | 9 | 1 | |
|
Epcor Agua Fria Surprise · Maricopa County |
128,040 | 5 | 0 | |
|
San Luis City of San Luis · Yuma County |
39,705 | 4 | 1 | |
|
Flowing Wells Irrigation District Tucson · Pima County |
16,000 | 6 | 1 | |
|
Winslow City of Winslow · Navajo County |
9,789 | 4 | 2 | |
|
Eloy City of Eloy · Pinal County |
8,999 | 6 | 1 | |
|
Arizona Water CO Bisbee Bisbee · Cochise County |
8,590 | 2 | 0 | |
|
Scua Upper Seven Mile County |
8,478 | 12 | 3 | |
|
Big Park Water Company Sedona · Yavapai County |
7,392 | 6 | 3 | |
|
Carl T Hayden Veterans Medical Center Maricopa County |
6,293 | 1 | 0 | |
|
Cocopah Casino County |
5,300 | 1 | 0 | |
|
Dilkon-Indian Wells-Greasewood-White Cone Ntua Dilcon, Indian Wells, Lower Greasewood · County |
4,986 | 2 | 1 | |
|
Aspc Lewis Complex Water System Buckeye · Maricopa County |
4,300 | 6 | 1 | |
|
Adoc Eyman Unit Florence · Pinal County |
3,969 | 8 | 2 | |
|
Polacca First Mesa Consolidated Villages · County |
3,890 | 6 | 4 | |
|
Kayenta Ntua Kayenta · County |
3,844 | 2 | 1 | |
|
Spanish Trail Water Company Tucson · Pima County |
3,822 | 3 | 0 | |
|
Arizona Village County |
3,211 | 10 | 2 | |
|
Scua Bylas Bylas · County |
3,160 | 12 | 3 | |
|
Palo Verde Nuclear Generating Station Wintersburg · Maricopa County |
3,000 | 1 | 1 | |
|
Chandler Heights Citrus Irrigation Dist Chandler · Maricopa County |
2,620 | 3 | 1 | |
|
Black Canyon City Wid Black Canyon City · Yavapai County |
2,437 | 6 | 1 | |
|
Ash Fork Water Service Ash Fork · Yavapai County |
2,350 | 2 | 0 | |
|
Chino Meadows II Chino Valley · Yavapai County |
2,350 | 6 | 4 | |
|
Leupp-Birdsprings-Tolani Lake Ntua Leupp, Birdsprings, Tolani Lake · County |
2,100 | 2 | 2 | |
|
Congress Dwid Congress · Yavapai County |
1,870 | 2 | 0 | |
|
Camp Verde School Dist 28 Camp Verde · Yavapai County |
1,810 | 4 | 3 | |
|
Hotevilla Village Hotevilla, Hotevilla/bacavi Community Sc · County |
1,601 | 8 | 4 | |
|
Many Farms Community School Bia Many Farms · County |
1,506 | 4 | 1 | |
|
Bearizona Williams · Coconino County |
1,423 | 6 | 0 | |
|
Inscription House-Navajo Mountain Ntua Inscription House, Broad Mesa West, Dry · County |
1,368 | 2 | 2 | |
|
Fredonia Town of Fredonia · Coconino County |
1,327 | 5 | 1 | |
|
Chilchinbeto Ntua Chilchinbeto · County |
1,276 | 3 | 1 | |
|
White Mountain Summer Homes Dwid Pinetop · Navajo County |
1,233 | 7 | 1 | |
|
Shonto Junction Ntua Shonto Junction · County |
1,146 | 1 | 1 | |
|
Jeddito Ntua Jeddito · County |
1,105 | 1 | 1 | |
|
Adoc Florence Asp Florence · Pinal County |
1,001 | 8 | 4 | |
|
Aguila Water Service Aguila · Maricopa County |
995 | 3 | 2 | |
|
Chinle High School Chinle High School · County |
975 | 4 | 2 | |
|
Klagetoh Ntua Klagetoh, South Ganado, Wide Ruins · County |
971 | 2 | 2 | |
|
Usfs Asnf Woods Canyon Aspen Camp Area Woods Canyon Lake · Coconino County |
900 | 1 | 0 | |
|
Greasewood Springs Community Boarding School Bia Lower Greasewood · County |
720 | 7 | 3 | |
|
City of Hope Phoenix Goodyear · Maricopa County |
700 | 3 | 0 | |
|
Usda FS Asnf Big Lake Rec Area II Greer · Apache County |
699 | 1 | 0 | |
|
Naco Water CO Main Naco · Cochise County |
658 | 1 | 1 | |
|
Camp LO Mia Lds Church Portal · Gila County |
650 | 1 | 1 | |
|
Usfs Conf Pine Flat Campground Oak Creek Canyon · Coconino County |
650 | 3 | 0 | |
|
View Motel Cottonwood · Yavapai County |
625 | 3 | 1 | |
|
Camp Geronimo Payson · Gila County |
600 | 3 | 1 | |
|
Sun Valley Farms Unit VI Queen Creek · Pinal County |
600 | 7 | 2 |
About this data
A system is counted once if any of its violations in the past three years involved Revised Total Coliform Rule (RTCR), including monitoring and reporting lapses. Rules violated and status in the table are for the whole system, not Revised Total Coliform Rule (RTCR) 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. Retrieved from ECHO on Oct 11, 2026.