Maryland
Frederick County drinking water quality
218 active public water systems serve 218,361 people in Frederick County. 190 are compliant, 28 had at least one EPA violation in the past three years, 1 is a designated serious violator, and 2 carry a health flag.
Needs attention
Community water systems
28 systems, largest first| System | Serves | Status | Rules violated, 3 yr | Unresolved |
|---|---|---|---|---|
|
New Design Frederick County |
74,911 | 1 | 0 | |
|
City of Frederick |
54,000 | 0 | 0 | |
|
Town of Walkersville |
8,440 | 1 | 0 | |
|
Fort Detrick |
7,900 | 1 | 0 | |
|
City of Brunswick |
7,312 | 0 | 0 | |
|
Town of Thurmont |
6,200 | 0 | 0 | |
|
Town of Middletown |
5,132 | 0 | 0 | |
|
Town of Emmitsburg |
2,921 | 1 | 0 | |
|
Mount Saint Marys University |
2,700 | 0 | 0 | |
|
Fountaindale South |
2,610 | 0 | 0 | |
|
Town of Myersville |
2,000 | 0 | 0 | |
|
Knolls of Windsor |
1,553 | 0 | 0 | |
|
Waterside |
1,509 | 0 | 0 | |
|
Sam Hill Estates |
1,036 | 0 | 0 | |
|
Cambridge Farms |
953 | 0 | 0 | |
|
Cloverhill 3 Consecutive to MD0100015 |
888 | 0 | 0 | |
|
Town of Woodsboro |
846 | 1 | 0 | |
|
Copperfield |
338 | 0 | 0 | |
|
Country Meadows of Frederick |
295 | 1 | 0 | |
|
White Rock |
256 | 0 | 0 | |
|
Rosemont Distribution System |
237 | 0 | 0 | |
|
Bradford Estates |
178 | 0 | 0 | |
|
Concord Estates Mobile Home Park |
150 | 1 | 1 | |
|
Libertytown East |
140 | 0 | 0 | |
|
Tranquility at Fredericktowne |
105 | 4 | 1 | |
|
Libertytown Apartments |
97 | 0 | 0 | |
|
Polings Mobile Home Park |
80 | 0 | 0 | |
|
Amelano Manor |
36 | 4 | 1 |
Non-community systems (190: schools, campgrounds, workplaces, restaurants)
These systems serve places people visit rather than homes.
Inactive systems (346, 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 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.