707 water systems in Arizona have at least one health-based violation on record. The system with the most health-based violations is Mohawk Valley School District in Roll with 348 health-based violations. Health-based violations mean a system exceeded an EPA maximum contaminant level or failed required treatment standards.
| Water System | City | Population | Health Violations | Total Violations |
|---|
| Mohawk Valley School District |
Roll | 171 |
348 | 727 |
| Polacca |
Polacca | 4,108 |
172 | 486 |
| Shungopavi |
Second Mesa | 1,756 |
149 | 252 |
| Cottonwood Municipal Water Cw1 |
Cottonwood | 11,023 |
144 | 186 |
| Papago Butte Dwid |
Maricopa | 530 |
141 | 228 |
| Wellton Town of |
Wellton | 3,000 |
136 | 591 |
| Antelope Peak Dwid |
Maricopa | 150 |
130 | 302 |
| Seba Dalkai Boarding School Bia |
Winslow | 250 |
126 | 186 |
| Mishongnovi (Upper Sipaulovi/Upper Mishongnovi) |
Second Mesa | 490 |
124 | 167 |
| Dilkon-Indian Wells-Greasewood-White Cone Ntua |
Fort Defiance | 4,986 |
105 | 137 |
| Kelvin Simmons Coop |
San Tan Valley | 28 |
97 | 514 |
| Gw Saguaro Dist Water Co - Rincon |
Phoenix | 232 |
89 | 147 |
| Hopi Cultural Center |
Kykotsmovi | 450 |
88 | 131 |
| Villa Grande Dwid |
Eloy | 283 |
85 | 167 |
| Toadlena Ntua |
Ft Defiance | 903 |
81 | 120 |
| Ranch Water Service Inc |
Kingman | 135 |
74 | 339 |
| New Saddleback Vista |
Maricopa | 100 |
74 | 231 |
| Aneth Ntua |
Ft Defiance | 1,481 |
71 | 105 |
| Scua Upper Seven Mile |
San Carlos | 8,478 |
62 | 436 |
| Cottonwood Municipal Water Vv3 |
Cottonwood | 1,458 |
60 | 94 |
| Thunderbird Farms Dwid |
Maricopa | 2,231 |
58 | 80 |
| Green Valley MHP |
Flagstaff | 190 |
56 | 116 |
| San Simon Dwid |
San Simon | 312 |
53 | 114 |
| Oak Creek Water District |
Sedona | 1,507 |
53 | 107 |
| Maricopa Mountain Dwid 1 |
Maricopa | 450 |
52 | 89 |
| Cibola Water Improvement District |
Tucson | 197 |
49 | 273 |
| White Horse Ranch Owners Association |
Prescott | 292 |
49 | 63 |
| Sierra Pacific Mobile Manor |
Yuma | 816 |
47 | 100 |
| City of Yuma |
Yuma | 103,264 |
46 | 160 |
| Pinedale Estates Dwid |
Lakeside | 208 |
46 | 84 |
| Sierra Vista RV Park |
Casa Grande | 200 |
46 | 59 |
| Epcor - Lakeside |
El Mirage | 1,775 |
45 | 335 |
| Fort Mcdowell Community |
Fountain Hills | 7,260 |
45 | 88 |
| Mexican Water Ntua |
Ft Defiance | 294 |
44 | 80 |
| Epcor - Moovalya Keys |
El Mirage | 1,298 |
43 | 265 |
| Lagoon Estates Wc Unit 2 |
Mohave Valley | 125 |
41 | 93 |
| Epcor - Marina Village |
El Mirage | 528 |
39 | 264 |
| Lake Roosevelt Water Plant |
Roosevelt | 100 |
38 | 82 |
| Epcor - Parker Dam |
El Mirage | 429 |
37 | 250 |
| Sweetwater Ntua |
Ft Defiance | 2,014 |
37 | 74 |
| Sun Leisure Estates Improvement District |
Yuma | 143 |
34 | 104 |
| Scua Bylas |
San Carlos | 3,160 |
32 | 219 |
| Bouse Dwid |
Bouse | 284 |
32 | 87 |
| Ds Water Company |
Desert Springs, | 258 |
32 | 58 |
| Desert Gardens RV Resort Co-Op, Inc |
Florence | 532 |
31 | 45 |
| Silver Creek RV Park |
Bullhead City | 280 |
30 | 89 |
| Adot Border Patrol |
Phoenix | 100 |
29 | 75 |
| Whispering Winds Apartments |
Chino Valley | 60 |
29 | 61 |
| Cameron Ntua |
Fort Defiance | 742 |
28 | 73 |
| Wenden Dwid |
Wenden | 360 |
28 | 67 |
| Big Park Water Company |
Sedona | 7,392 |
27 | 1,312 |
| Fort Defiance-Window Rock-St Michaels Ntua |
Ft Defiance | 12,869 |
27 | 67 |
| Payson Water - East Verde Estates |
Payson | 375 |
27 | 58 |
| Foothills Utilities Kingman East |
Yuma | 2,538 |
26 | 124 |
| Jones Coop Water Assoc |
Yuma | 35 |
26 | 111 |
| Epcor - Rio Lindo |
El Mirage | 79 |
25 | 192 |
| Monte Vista Water Company |
Tucson | 150 |
25 | 81 |
| Pine Valley Water Company |
Sedona | 400 |
25 | 55 |
| Shepard Water Company |
Yuma | 430 |
24 | 143 |
| Yuma Lakes Resort |
Parker | 652 |
24 | 104 |
| Rough Rock Community High School Bia |
Chinle | 350 |
24 | 74 |
| Beaver Creek School |
Rimrock | 400 |
24 | 53 |
| Todahaidekani Ntua |
Ft Defiance | 301 |
24 | 48 |
| Second Mesa Day School - Bia |
Second Mesa | 366 |
23 | 135 |
| Shangri La Ranch |
New River | 345 |
23 | 70 |
| Hopi High School - Bia |
Keams Canyon | 1,150 |
22 | 257 |
| Morenci Water Elec Co Main |
Phoenix | 4,108 |
21 | 156 |
| Dishchii Bikoh Community School - Bia Charter |
White River | 622 |
21 | 126 |
| Mulberry Park MHP |
Cottonwood | 28 |
21 | 114 |
| Williams City of |
Williams | 3,145 |
20 | 123 |
| Red Mesa Ntua |
Ft Defiance | 1,023 |
20 | 44 |
| Cocopah Casino |
Somerton | 5,300 |
19 | 26 |
| Cottonwood Municipal Water Vv6 |
Cottonwood | 4,509 |
18 | 84 |
| Copper Mountain Ranch Cfd |
Casa Grande | 1,071 |
18 | 54 |
| Rio Verde RV Park |
Cottonwood | 90 |
18 | 36 |
| Epcor - Holiday Harbor |
El Mirage | 559 |
17 | 169 |
| Colorado River Regional Water System |
Parker | 8,490 |
17 | 61 |
| Lower Moencopi - Spring Source |
Tuba City | 465 |
17 | 54 |
| Maricopa Agriculture Center |
Maricopa | 100 |
16 | 77 |
| Grandview Water Company |
Buckeye | 50 |
16 | 63 |
| Ak-Chin Santa Cruz Commerce Center |
Maricopa | 94 |
16 | 19 |
| Majestic View Water Improvement District |
Kingman | 70 |
15 | 222 |
| Cameron Trading Post |
Cameron | 1,270 |
15 | 192 |
| Coldwater Canyon 1 |
Tucson | 541 |
15 | 93 |
| Desert Star Community School |
Cornville | 200 |
15 | 52 |
| Sonoita Mercantile Water System |
Sonoita | 125 |
15 | 46 |
| Cordes Junction Motel RV Park |
Mayer | 250 |
15 | 24 |
| Cienega Water Company Inc |
Parker | 108 |
14 | 191 |
| Pomerene Dwid |
Pomerene | 1,030 |
14 | 149 |
| Snowbird RV Park |
Fort Mohave | 180 |
14 | 135 |
| Valle Escondido |
Maricopa | 405 |
14 | 62 |
| Destination at Oak Creek |
Sedona | 50 |
14 | 61 |
| Krazy K RV Park |
Camp Verde | 380 |
14 | 30 |
| Wekiva Falls Resort |
Gilbert | 352 |
14 | 14 |
| Springerville Town of |
Springerville | 1,972 |
13 | 292 |
| Tombstone City of |
Tombstone | 1,545 |
13 | 149 |
| Indian Hills Estates |
Winkelman | 30 |
13 | 75 |
| Country Lane Trailer Park |
Show Low | 450 |
13 | 74 |
| Cocopah Bend RV & Golf Resort |
Somerton | 1,095 |
13 | 67 |
| Stonehouse Lodge |
Phoenix | 35 |
13 | 63 |