Arizona

Pima County drinking water quality

193 active public water systems serve 1,136,697 people in Pima County. 66 are compliant, 127 had at least one EPA violation in the past three years, 2 are designated serious violators, and 5 carry a health flag.

Active systems 193 142 community systems

People served 1.1M by public water systems

Systems with violations 127 66% of active systems, past 3 years

Serious violators 2 5 systems carry a health flag

Needs attention

Rancho Sierrita Well Assoc AZ0410286 · Tucson · Community water system · Serves 51 3 rules violated in the past three years. Unresolved: Revised Total Coliform Rule and Lead and Copper Rule.

Siete Casas Joint Venture AZ0410242 · Tucson · Community water system · Serves 25 2 rules violated in the past three years. Unresolved: Revised Total Coliform Rule and Public Notice Rule and Revised PN Rule.

Marana Dwid Culver AZ0410070 · Marana · Community water system · Serves 709 4 rules violated in the past three years. Unresolved: Ground Water Rule.

Tucson Racquet & Fitness Club AZ0410222 · Tucson · Non-Transient non-community system · Serves 330 3 rules violated in the past three years. Unresolved: Revised Total Coliform Rule.

Calportland Rillito Cement Plant AZ0420011 · Rillito · Non-Transient non-community system · Serves 184 4 rules violated in the past three years. Unresolved: Revised Total Coliform Rule and Lead and Copper Rule.

Community water systems

142 systems, largest first

System	Serves	Rules violated, 3 yr	Unresolved
GW Ocotillo Water Valley View Acres Ryan Field	458	0	0
Campbell Estates MHP Tucson	450	1	0
Thim Utility Company 2 Tucson	445	1	0
Cactus Country RV Resort Tucson	420	3	1
Ajo Dwid Ajo	405	2	0
Why Dwid Why	400	2	0
GW Farmers Water CO Sahuarita Green Valley	396	0	0
Diamond Grove Mobile Home Estates Tucson	385	1	0
GW Farmers Water CO Sahuarita Highland Sahuarita	384	0	0
Lazy C Water Service Tucson	359	2	0
Federal Correctional Inst Tucson	350	9	0
Bella Capri MHP Tucson	342	2	0
Thim Utility Company Three Points	310	0	0
Shiloh Water Company Sahuarita	309	3	0
Los Arboles Mobile Home Park Sahuarita	303	0	0
Valle Verde del Norte Green Valley	300	4	1
Mesaland Water Company Tucson	294	5	1
MT Lemmon Dwid Mount Lemmon	290	2	1
Rio Viejo Water Tucson	272	2	0
Rio Mercado Water Tucson	266	5	0
LA Casita Water Company 2 Tucson	264	2	1
Far Horizons MHP Tucson	258	0	0
Sierrita Mountain Water Coop Tucson	258	4	1
Tierra Linda HOA Water Company Tucson	258	1	0
Thim Utility Company Well 9 Three Points	254	1	0
LA Cholla Airpark Tucson	250	2	1
Thim Water Company 2 Tucson	247	0	0
GW Ocotillo Water Silverbell West Tucson	231	0	0
Ranchwood Community Tucson	225	2	0
GW Saguaro Dist Water CO Tala Way Tucson	221	0	0
Desert Shores RV MHP Tucson	220	2	1
Rio Vista Mobile Home Park Tucson	217	0	0
Halcyon Acres Water Users Association Tucson	215	1	0
GW Saguaro Dist Water CO Rincon Tucson	209	3	0
Crescent Manor MHP Tucson	200	1	0
Marana Municipal Tortolita Mountain Marana	200	0	0
LA Casita Water Company 1 Tucson	171	1	1
Silver Cholla LLC Tucson	168	0	0
Casitas de Castilian Tucson	167	5	1
Rillito Water Users Assoc Rillito	165	4	2
GW Saguaro Dist Water CO Mirabell Tucson	162	2	0
Wildflower Water Coop Three Points	157	1	0
Pantano Water Coop Vail	156	2	2
Via Verde West MHP Tucson	156	1	1
GW Ocotillo Water Thunderhead Tucson	153	0	0
Arivaca Townsite Water Coop Arivaca	150	0	0
Desert Water Coop Tucson	150	3	0
North la Cholla MHP Tucson	150	0	0
Samalayuca Improvement Assoc Tucson	150	1	0
Raindance Water Coop Tucson	148	0	0

Non-community systems (51: schools, campgrounds, workplaces, restaurants)

These systems serve places people visit rather than homes.

System	Serves	Rules violated, 3 yr	Unresolved
University of Arizona Tucson	50,000	0	0
Tucson Medical Center Tucson	3,000	4	1
UA Tech Park Rita Road Tucson	3,000	2	0
Marana High School Marana	2,450	1	0
Marana Estes Elementary School Marana	2,000	1	0
Vail School District Elementary School Vail	1,680	3	0
Saguaro National Park Tucson	1,440	2	0
Salpointe Catholic High School Tucson	1,300	0	0
Tucson Country Day School Tucson	800	0	0
Asarco Mission Unit Green Valley	586	0	0
Usfs Cnf Sabino Canyon Stop 8 Sabino Canyon	550	0	0
Thim Utility Corporation VFW Three Points	413	0	0
Usfs Cnf Loma Linda Mount Lemmon	350	1	0
Usfs Cnf Ski Lodge Mount Lemmon	350	0	0
AZ State Parks Catalina Mountain Catalina	330	1	0
Tucson Racquet & Fitness Club Tucson	330	3	1
Camp Whispering Pines Mount Lemon	240	0	0
Saint Phillips Plaza Tucson	220	2	0
Santa Catalina Catholic Church Tucson	212	2	0
Pcnr Colossal Cave Tucson	210	1	0
Camp Lawton Mount Lemmon	200	2	0
Caterpillar INC Green Valley	200	0	0
Latter Day Saints Church Summerhaven	200	4	1
Silverbell Mining, LLC Marana	200	3	0
Calportland Rillito Cement Plant Rillito	184	4	2
Greenfields Country Day School Tucson	163	6	0
Bayer R&d Services LLC Marana Marana	160	2	0
Caballo Loco Ranch Sasabe	150	3	1
Pcnr Gilbert Ray Tmp Tucson	150	2	0
Tanque Verde Guest Ranch Tucson	150	2	0
Lil Abners Steakhouse Tucson	100	0	0
Pcnr Motor Sports Tucson	100	0	0
Pcnr Picture Rocks Tucson	100	1	0
Hot Rod Water Vail	90	3	0
Pcnr Fairgrounds Tucson	87	0	0
Tucson Ready Mix Orange Grove Tucson	80	0	0
Campbell Avenue Farms Tucson	65	0	0
White Stallion Guest Ranch Tucson	60	1	0
Marana Municipal Airport Marana	55	0	0
Buenos Aires National Wildlife Refuge Sasabe	54	7	1
Pcnr Three Point Three Points	52	2	0
Sopori School Park Tucson	50	0	0
Lukeville Border Station Lukeville	45	1	0
Elkhorn Ranch Sasabe	40	1	0
Hitda Training Center Tucson	35	0	0
Sasabe Border Village Sasabe	31	5	1
Soldier Camp Permittees Summerhaven	30	3	0
EL Mesquital Guest Ranch Tucson	25	0	0
Gringo Pass TP Lukeville	25	1	0
Pcnr la Posta Quemada Tucson	25	0	0
Redwood Lodge Tucson	25	1	0

Inactive systems (322, no longer operating or reporting)

Kept for the record and excluded from the county totals above. Browse inactive systems.

About this data

Totals cover active systems. Systems serving more than one county are counted in each county. EPA counts the rules a system was in violation of, not the individual violations; one rule can carry several.

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.

Pima County drinking water quality

Needs attention

Community water systems

Compliant

Violations in the past 3 years

Serious violator

Health flag

Inactive system