Water quality for ZIP code 94511
ZIP 94511 covers Bethel Island in Contra Costa County, California, one of 43 ZIP codes in the county. 84 active public water systems serve the county; 21 had an EPA violation in the past three years.
Most likely your provider
Your location is within the outer bounds of this system's EPA service area.
Other community water systems in Contra Costa County
38 systems, nearest first| System | Serves | Status | Rules violated, 3 yr | Distance |
|---|---|---|---|---|
| Angler S Ranch #3 |
60 | 1 | 0.9 mi | |
| Willow Mobile Home Park |
481 | 0 | 0.9 mi | |
| Anglers Subdivision 4 |
99 | 1 | 1.0 mi | |
| Riverview Water Association |
230 | 1 | 1.1 mi | |
| Bethel Island Mutual Water CO |
123 | 1 | 1.2 mi | |
| Farrar Park Property Owners |
140 | 0 | 1.3 mi | |
| Russos Mobile Park |
110 | 2 | 1.3 mi | |
| Dutch Slough Water Works |
49 | 1 | 1.4 mi | |
| Sandmound Mutual |
100 | 2 | 1.5 mi | |
| Marina Mobile Manor |
75 | 0 | 1.6 mi | |
| Willow Park Marina |
380 | 1 | 1.8 mi | |
| Pleasantimes Mutual Water CO |
644 | 0 | 1.8 mi | |
| Bethel Island Estates |
200 | 0 | 1.9 mi | |
| Sandy Point Mobile Home Park |
67 | 2 | 2.0 mi | |
| Bethel Island MHC |
185 | 0 | 2.0 mi | |
| Delta Mutual Water Company |
333 | 1 | 2.4 mi | |
| Oakley Mutual Water Company |
170 | 2 | 3.1 mi | |
| Diablo Water District |
47,158 | 0 | 3.8 mi | |
| Knightsen Community Water System |
73 | 0 | 4.0 mi | |
| Big Oak Mobile Home Park Water |
156 | 0 | 4.1 mi | |
| Ccwd/brentwood Wtp |
0 | 0 | 6.0 mi | |
| Randall-Bold Water Treatment Plant |
1 | 0 | 6.1 mi | |
| Orwood Resort |
350 | 2 | 6.7 mi | |
| Brentwood Brentwood |
64,513 | 0 | 7.8 mi | |
| Town of Discovery Bay |
16,790 | 0 | 8.8 mi |
Non-community systems in Contra Costa County (45: schools, campgrounds, workplaces, restaurants)
These systems serve places you visit rather than homes.
About this data
Water systems are matched to Contra Costa County, the county this ZIP code lies in, nearest to the ZIP code's centre first. Your exact provider depends on your address and connection; the largest community water system in a county is usually the city or town utility. Distances are measured to the centre of the service area EPA publishes for the system.
ZIP code areas and town boundaries come from the U.S. Census Bureau's 2020 ZCTA files.
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.