California
Merced County drinking water quality
119 active public water systems serve 266,400 people in Merced County. 82 are compliant, 37 had at least one EPA violation in the past three years, 1 is a designated serious violator, and 10 carry a health flag.
Needs attention
Community water systems
22 systems, largest first| System | Serves | Status | Rules violated, 3 yr | Unresolved |
|---|---|---|---|---|
|
City of Merced Merced |
96,073 | 0 | 0 | |
|
City of los Banos Los Banos |
48,896 | 1 | 0 | |
|
City of Atwater Atwater |
29,479 | 0 | 0 | |
|
City of Livingston Livingston |
14,894 | 1 | 1 | |
|
Winton Water & Sanitary Dist |
9,745 | 1 | 1 | |
|
Delhi Cwd |
7,784 | 1 | 1 | |
|
City of Dos Palos Dos Palos |
7,452 | 2 | 1 | |
|
City of Gustine Gustine |
6,138 | 1 | 1 | |
|
Cal AM Meadowbrook |
5,723 | 0 | 0 | |
|
Hilmar County Water District |
5,504 | 1 | 0 | |
|
Planada Csd |
4,164 | 1 | 1 | |
|
Santa Nella County Water District |
2,211 | 0 | 0 | |
|
LE Grand Comm Services Dist |
1,739 | 2 | 1 | |
|
John Latoracca Correctional Facility |
800 | 1 | 1 | |
|
Black Rascal Water Company |
367 | 1 | 1 | |
|
Volta Community SD |
366 | 2 | 1 | |
|
Ballico Csd |
238 | 1 | 0 | |
|
San Luis Hills |
221 | 0 | 0 | |
|
Castle Airport |
150 | 1 | 1 | |
|
EL Nido Mobile Home Park |
137 | 1 | 0 | |
|
Country Club County WD |
64 | 3 | 2 | |
|
Evergreen Mobile Home Park |
36 | 1 | 1 |
Non-community systems (97: schools, campgrounds, workplaces, restaurants)
These systems serve places people visit rather than homes.
Inactive systems (127, 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 California 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.