Chlorine (MRDL) violations in Arizona
274 active public water systems in Arizona had a Chlorine (MRDL) violation in the past three years, 24 of them in the latest quarter of EPA's data. What Chlorine (MRDL) is and why it matters.
Health effects: Acute high-dose exposure to chlorinated water can cause eye and nose irritation, stomach discomfort, and nausea. Chronic exposure above the MRDL is primarily a concern because elevated chlorine accelerates formation of trihalomethanes and haloacetic acids, which are associated with increased cancer risk over time.
Systems with a Chlorine (MRDL) violation
Latest quarter first, then largest first| System | Serves | Status | Rules violated, 3 yr | Unresolved |
|---|---|---|---|---|
|
88 Shades RV Park Quartzsite · La Paz County |
488 | 1 | 0 | |
|
Aspb Kartchner Caverns Benson · Cochise County |
483 | 3 | 0 | |
|
White Mountain Water Company Show Low · Navajo County |
475 | 4 | 0 | |
|
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 | |
|
Campbell Estates MHP Tucson · Pima County |
450 | 1 | 0 | |
|
Duncan Elementary School Duncan · Greenlee County |
450 | 4 | 1 | |
|
Highland Pine Dwid Prescott · Yavapai County |
450 | 4 | 0 | |
|
Country Club Acres Water INC Wickenburg · Maricopa County |
431 | 4 | 0 | |
|
Grand Canyon Junction Hydro Valle · Coconino County |
430 | 6 | 0 | |
|
Shepard Water Company Martinez Lake · Yuma County |
430 | 7 | 2 | |
|
Yavapai Community College Agricultural Chino Valley · Yavapai County |
420 | 1 | 0 | |
|
Asarco Hayden Operations Hayden · Gila County |
417 | 5 | 0 | |
|
Katherine Heights Bullhead City · Mohave County |
415 | 7 | 0 | |
|
Payson Water Whispering Pines Payson · Gila County |
403 | 2 | 0 | |
|
Eden Water Company INC Safford · Graham County |
400 | 6 | 0 | |
|
Mobile Gardens Dwid Wittmann · Maricopa County |
400 | 5 | 0 | |
|
Picacho Peak RV Resort Red Rock · Pinal County |
400 | 6 | 1 | |
|
Saguaro View Mgmt Company Surprise · Maricopa County |
400 | 4 | 0 | |
|
Round Rock Elementary School Round Rock · County |
396 | 2 | 1 | |
|
Granite Mountain Water Company Prescott · Yavapai County |
381 | 5 | 3 | |
|
Silverbell Irrigation & Drainage Dist Eloy · Pinal County |
375 | 6 | 0 | |
|
Skyline Resort RV Park Magma · Pinal County |
375 | 6 | 1 | |
|
Lazy C Water Service Tucson · Pima County |
359 | 2 | 0 | |
|
CS Mormon Lake Water Company Mormon Lake · Coconino County |
353 | 3 | 0 | |
|
CS Loma Linda Water Company Clifton · Greenlee County |
351 | 6 | 0 | |
|
Federal Correctional Inst Tucson · Pima County |
350 | 9 | 0 | |
|
Gowan Milling LLC Yuma · Yuma County |
350 | 7 | 1 | |
|
Ganado Mission Sage Memorial Hospital Ganado · County |
349 | 2 | 1 | |
|
Low Mountain Boarding School Bia Low Mountain · County |
339 | 3 | 2 | |
|
CS White Hills Water Company Unit 1 White Hills · Mohave County |
338 | 4 | 0 | |
|
CS White Hills Water Company Units 3 4 6 White Hills · Mohave County |
333 | 4 | 0 | |
|
Lower Moencopi Consecutive System Lower Moencopi · County |
326 | 6 | 3 | |
|
JO Combs Elementary School Queen Creek · Pinal County |
325 | 4 | 2 | |
|
Shiloh Water Company Sahuarita · Pima County |
309 | 3 | 0 | |
|
Nps Temple Bar Wtp Temple Bar · Mohave County |
305 | 4 | 0 | |
|
GW -Bwc, Inc. Nswc Scottsdale · Maricopa County |
301 | 1 | 0 | |
|
Resolution Copper Company Superior · Pinal County |
300 | 2 | 0 | |
|
Tonalea (red Lake) Day School Bia Tonalea, Red Lake · County |
300 | 3 | 0 | |
|
Valle Verde del Norte Green Valley · Pima County |
300 | 4 | 1 | |
|
Salome Water Company Salome · La Paz County |
289 | 4 | 1 | |
|
Sun Valley Utilities Sun Valley · Navajo County |
287 | 8 | 3 | |
|
Picacho Dwid Picacho · Pinal County |
285 | 4 | 0 | |
|
Villa Grande Dwid Eloy · Pinal County |
283 | 7 | 0 | |
|
Cocopah East County |
280 | 3 | 0 | |
|
Ghr Landowners Assn Water Coop White Hills · Mohave County |
280 | 7 | 2 | |
|
CS Gardner Water Company Payson · Gila County |
266 | 6 | 0 | |
|
Grand Canyon Drinking Water Williams · Coconino County |
260 | 1 | 0 | |
|
Sierrita Mountain Water Coop Tucson · Pima County |
258 | 4 | 1 |
About this data
A system is counted once if any of its violations in the past three years involved Chlorine (MRDL), including monitoring and reporting lapses. Rules violated and status in the table are for the whole system, not Chlorine (MRDL) 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.