Water quality for ZIP code 20661
ZIP 20661 covers Cobb Island in Charles County, Maryland, one of 22 ZIP codes in the county. 172 active public water systems serve the county; 96 had an EPA violation in the past three years.
Most likely your provider
Other community water systems in Charles County
48 systems, largest first| System | Serves | Status | Rules violated, 3 yr |
|---|---|---|---|
| Town of la Plata |
11,535 | 0 | |
| Bryans Road |
6,260 | 1 | |
| Town of Indian Head |
4,100 | 0 | |
| Naval Support Facility, Indian Head |
3,321 | 0 | |
| Potomac Heights |
1,800 | 0 | |
| Swan Point |
945 | 1 | |
| Cliffton on the Potomac |
744 | 2 | |
| Hunters Brooke/falcon Ridge Subd |
614 | 2 | |
| Charles County Gardens Water |
551 | 1 | |
| Benedict |
376 | 1 | |
| Kings Manor White Plains Water Co, INC |
372 | 1 | |
| Pomunk Water Company Distribution System |
340 | 1 | |
| Idlewood Park |
320 | 0 | |
| Bel Alton |
311 | 2 | |
| Chapel Point Wds/ Jude House/ Comm Ctr |
280 | 1 | |
| Aqualand Campground |
240 | 2 | |
| Ellenwood |
229 | 1 | |
| Red Hill Water Company, Inc. |
200 | 1 | |
| Mariellen Park |
184 | 1 | |
| Oak Hill Water Company, LLC |
180 | 1 | |
| Mount Carmel Woods |
175 | 1 | |
| Newtown Village |
170 | 1 | |
| DU Mar Estates Water Company |
150 | 2 | |
| Pomfret Estates Utilco, Inc. |
150 | 1 | |
| Turkey Hill Water Company |
150 | 2 |
Non-community systems in Charles County (123: schools, campgrounds, workplaces, restaurants)
These systems serve places you visit rather than homes.
About this data
Water systems are matched to Charles County, the county this ZIP code lies in, largest 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.
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.