Water quality for ZIP code 20636
St. Mary's County, Maryland, one of 26 ZIP codes in the county. 202 active public water systems serve the county; 46 had an EPA violation in the past three years.
Most likely your provider
Other community water systems in St. Mary's County
37 systems, nearest first| System | Serves | Status | Rules violated, 3 yr | Distance |
|---|---|---|---|---|
| Forrest Farm Subdivision |
577 | 1 | 3.1 mi | |
| Holland Forest |
139 | 1 | 3.7 mi | |
| Town of Leonardtown |
5,000 | 1 | 5.1 mi | |
| Christmas Tree Farm Trailer Park |
100 | 3 | 5.5 mi | |
| King & Kennedy |
169 | 1 | 5.8 mi | |
| Lexington Park |
43,030 | 3 | 6.0 mi | |
| Villages at Leonardtown |
239 | 1 | 6.2 mi | |
| Leonardtown Farm |
193 | 1 | 6.9 mi | |
| Mulberry South |
65 | 1 | 7.1 mi | |
| Wilderness Run |
511 | 2 | 7.5 mi | |
| Grandview Haven |
269 | 1 | 7.7 mi | |
| Breton Bay |
1,012 | 2 | 7.9 mi | |
| Hunting Quarters |
715 | 1 | 7.9 mi | |
| Lord Calvert Trailer Park |
892 | 1 | 8.3 mi | |
| St. Clements Shores |
620 | 1 | 8.9 mi | |
| Patuxent Naval Air Station (navfac-Wash) |
22,000 | 1 | 9.3 mi | |
| Birch Manor |
272 | 1 | 9.5 mi | |
| Langley Mobile Home Park |
175 | 2 | 9.6 mi | |
| Mount Pleasant Water Co., Inc. |
150 | 2 | 10.0 mi | |
| Persimmon Hills |
514 | 1 | 10.0 mi | |
| Greenbrier |
1,161 | 1 | 10.3 mi | |
| Cedar Cove |
2,728 | 1 | 10.5 mi | |
| Southgate |
188 | 1 | 10.6 mi | |
| Hearts Desire |
65 | 1 | 10.8 mi | |
| Fox Meadow |
128 | 1 | 10.9 mi |
Non-community systems in St. Mary's County (164: schools, campgrounds, workplaces, restaurants)
These systems serve places you visit rather than homes.
About this data
Water systems are matched to St. Mary's 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 Maryland 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.