Water quality for ZIP code 20621
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 |
|---|---|---|---|---|
| Wicomico Shores |
1,262 | 1 | 4.7 mi | |
| Country Lakes |
3,016 | 1 | 5.4 mi | |
| St. Clements Shores |
620 | 1 | 6.1 mi | |
| Grandview Haven |
269 | 1 | 6.8 mi | |
| Villages at Leonardtown |
239 | 1 | 7.0 mi | |
| Birch Manor |
272 | 1 | 7.5 mi | |
| Wild Goose Crest Subdivision |
65 | 1 | 8.3 mi | |
| Breton Bay |
1,012 | 2 | 8.4 mi | |
| King & Kennedy |
169 | 1 | 8.5 mi | |
| Persimmon Hills |
514 | 1 | 8.8 mi | |
| Town of Leonardtown |
5,000 | 1 | 9.0 mi | |
| Mulberry South |
65 | 1 | 9.3 mi | |
| Holland Forest |
139 | 1 | 9.6 mi | |
| Charlotte Hall VA Home |
270 | 1 | 10.5 mi | |
| Laurel Ridge |
560 | 1 | 11.1 mi | |
| Hearts Desire |
65 | 1 | 11.2 mi | |
| Wilderness Run |
511 | 2 | 11.5 mi | |
| Charlotte Hall |
615 | 1 | 11.5 mi | |
| Forrest Farm Subdivision |
577 | 1 | 11.9 mi | |
| Christmas Tree Farm Trailer Park |
100 | 3 | 12.2 mi | |
| Leonardtown Farm |
193 | 1 | 12.6 mi | |
| Rolling Acres |
699 | 1 | 12.8 mi | |
| Fenwick Manor |
234 | 1 | 13.2 mi | |
| Hunting Quarters |
715 | 1 | 16.1 mi | |
| Lexington Park |
43,030 | 3 | 16.7 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. Retrieved from ECHO on Oct 11, 2026.