Systems reaching a study comparison level
16.9%12 of 71 active community water systems with complete monitoring
All 71 systems had complete monitoring. 12 reached at least one study comparison level; 59 did not. “Study comparison level” means the dated EPA technical cutoff used in this January 2026 research release. It does not determine household exposure, health risk, or current legal compliance.
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ZIP codes are used only to route visitors to public water systems that reported serving them. Confirm the actual provider using a water bill or utility record.
Compound summary
System counts in Maryland
Each count shows how many included water systems reached the named study level.
| Study comparison | Systems reaching level | Water systems included | Percent |
|---|---|---|---|
| PFOA: study level 4.05 ppt (April 2024 EPA level: 4 ppt) | 11 | 71 | 15.5% |
| PFOS: study level 4.05 ppt (April 2024 EPA level: 4 ppt) | 10 | 71 | 14.1% |
| PFHxS: study level 15 ppt (April 2024 EPA level: 10 ppt) | 0 | 71 | 0.0% |
| PFNA: study level 15 ppt (April 2024 EPA level: 10 ppt) | 0 | 71 | 0.0% |
| HFPO-DA: study level 15 ppt (April 2024 EPA level: 10 ppt) | 0 | 71 | 0.0% |
| Hazard Index: study level 1.5 with at least two detected components (April 2024 EPA level: 1) | 0 | 71 | 0.0% |
System directory
Community water systems with complete monitoring
Each PWSID appears once, preventing double counting across ZIP associations.
| Public water system | PWSID | Population served | Primary source | Sampling locations | Study comparison |
|---|---|---|---|---|---|
| BOONSBORO - KEEDYSVILLE | MD0210002 | 4,250 | Surface water | 3 | Reached a study level |
| BROAD CREEK | MD0020004 | 26,033 | Ground water | 1 | Below the study levels |
| BRYANS ROAD | MD0080033 | 6,260 | Ground water | 4 | Below the study levels |
| CHAPEL HILL - ABERDEEN PROVING GROUNDS | MD0120002 | 15,000 | Ground water | 1 | Below the study levels |
| CHARLOTTE HALL VA HOME | MD0180217 | 270 | Ground water | 1 | Below the study levels |
| CHESAPEAKE RANCH ESTATES | MD0040004 | 9,500 | Ground water | 4 | Below the study levels |
| CITY OF ABERDEEN | MD0120001 | 18,006 | Surface water purchased | 2 | Reached a study level |
| CITY OF ANNAPOLIS | MD0020001 | 35,000 | Ground water | 1 | Below the study levels |
| CITY OF BALTIMORE | MD0300002 | 1,600,000 | Surface water | 3 | Below the study levels |
| CITY OF BOWIE, MD | MD0160002 | 25,000 | Ground water | 1 | Below the study levels |
| CITY OF BRUNSWICK | MD0100005 | 7,312 | Surface water | 2 | Below the study levels |
| CITY OF CAMBRIDGE | MD0090002 | 15,000 | Ground water | 4 | Below the study levels |
| CITY OF CUMBERLAND | MD0010008 | 27,039 | Surface water | 1 | Below the study levels |
| CITY OF FREDERICK | MD0100015 | 54,000 | Surface water | 4 | Below the study levels |
| CITY OF FROSTBURG | MD0010011 | 11,000 | Surface water | 1 | Below the study levels |
| CITY OF HAGERSTOWN | MD0210010 | 92,200 | Surface water | 1 | Below the study levels |
| CITY OF HAVRE DE GRACE | MD0120012 | 14,000 | Surface water | 1 | Below the study levels |
| CITY OF POCOMOKE CITY | MD0230006 | 4,100 | Ground water | 1 | Below the study levels |
| CITY OF ROCKVILLE | MD0150003 | 52,000 | Surface water | 1 | Below the study levels |
| CITY OF SALISBURY | MD0220004 | 30,343 | Ground water | 2 | Reached a study level |
| CITY OF TANEYTOWN | MD0060012 | 6,750 | Ground water | 7 | Reached a study level |
| CITY OF WESTMINSTER, MD | MD0060015 | 35,256 | Surface water | 10 | Reached a study level |
| CROFTON-ODENTON | MD0020008 | 62,986 | Ground water | 1 | Below the study levels |
| EASTERN CORRECTIONAL INSTITUTE | MD0190013 | 3,500 | Ground water | 1 | Below the study levels |
| EASTERN REGION ALLEGANY DISTRIB. SYSTEM | MD0010005 | 5,703 | Surface water purchased | 1 | Below the study levels |
| EASTON UTILITIES | MD0200003 | 17,357 | Ground water | 4 | Below the study levels |
| ELKTON WEST | MD0070015 | 3,500 | Surface water purchased | 1 | Below the study levels |
| FORT GEORGE G. MEADE | MD0020012 | 62,234 | Ground water | 1 | Below the study levels |
| FREEDOM DISTRICT | MD0060002 | 24,867 | Surface water | 1 | Below the study levels |
| GLEN BURNIE-BROADNECK | MD0020017 | 290,606 | Ground water | 4 | Below the study levels |
| HARFORD COUNTY D.P.W. | MD0120016 | 104,567 | Surface water | 3 | Below the study levels |
| HOWARD COUNTY D.P.W. DISTRIBUTION | MD0130002 | 286,158 | Surface water purchased | 2 | Below the study levels |
| LAVALE SANITARY COMMISSION | MD0010016 | 5,500 | Surface water purchased | 2 | Below the study levels |
| LEXINGTON PARK | MD0180007 | 43,030 | Ground water | 2 | Below the study levels |
| MARYLAND AMERICAN WATER COMPANY | MD0120003 | 13,200 | Surface water | 2 | Reached a study level |
| MIDLAND-LONACONING | MD0010018 | 5,000 | Surface water | 2 | Below the study levels |
| MYSTIC HARBOUR | MD0230011 | 5,945 | Ground water | 4 | Below the study levels |
| NAVAL SUPPORT FACILITY, INDIAN HEAD | MD0080058 | 3,321 | Ground water | 4 | Below the study levels |
| NEW DESIGN - FREDERICK COUNTY | MD0100030 | 74,911 | Surface water | 1 | Below the study levels |
| OCEAN PINES | MD0230005 | 11,890 | Ground water | 5 | Below the study levels |
| PATUXENT NAVAL AIR STATION (NAVFAC-WASH) | MD0180022 | 22,000 | Ground water | 13 | Below the study levels |
| PINEY POINT | MD0180034 | 672 | Ground water | 1 | Below the study levels |
| PRINCE FREDERICK | MD0040011 | 4,371 | Ground water | 2 | Below the study levels |
| SEVERN WATER COMPANY | MD0020027 | 5,447 | Ground water | 1 | Below the study levels |
| SOLOMONS | MD0040027 | 3,811 | Ground water | 2 | Below the study levels |
| STEVENSVILLE | MD0170019 | 9,155 | Ground water | 6 | Below the study levels |
| THE PROVINCES | MD0020029 | 3,991 | Ground water | 1 | Below the study levels |
| TOWN OF BERLIN | MD0230001 | 4,500 | Ground water | 3 | Below the study levels |
| TOWN OF CENTREVILLE | MD0170001 | 3,322 | Ground water | 2 | Below the study levels |
| TOWN OF CHESAPEAKE BEACH | MD0040003 | 5,000 | Ground water | 3 | Below the study levels |
| TOWN OF CHESTERTOWN | MD0140002 | 5,400 | Ground water | 1 | Below the study levels |
| TOWN OF DELMAR | MD0220001 | 4,500 | Ground water | 1 | Below the study levels |
| TOWN OF ELKTON | MD0070011 | 15,625 | Surface water | 5 | Reached a study level |
| TOWN OF HAMPSTEAD | MD0060003 | 6,600 | Ground water | 10 | Reached a study level |
| TOWN OF HANCOCK | MD0210012 | 1,921 | Ground water | 1 | Below the study levels |
| TOWN OF INDIAN HEAD | MD0080020 | 4,100 | Ground water | 3 | Below the study levels |
| TOWN OF LA PLATA | MD0080025 | 11,535 | Ground water | 5 | Below the study levels |
| TOWN OF MANCHESTER | MD0060006 | 4,954 | Ground water | 11 | Reached a study level |
| TOWN OF MILLINGTON | MD0140010 | 625 | Ground water | 1 | Below the study levels |
| TOWN OF MOUNT AIRY | MD0060007 | 9,890 | Ground water | 5 | Reached a study level |
| TOWN OF NORTH EAST | MD0070016 | 8,600 | Surface water | 2 | Below the study levels |
| TOWN OF OCEAN CITY | MD0230003 | 30,000 | Ground water | 2 | Below the study levels |
| TOWN OF PERRYVILLE | MD0070018 | 4,413 | Surface water | 1 | Below the study levels |
| TOWN OF POOLESVILLE | MD0150002 | 6,005 | Groundwater under influence of surface water | 9 | Reached a study level |
| TOWN OF PRINCESS ANNE | MD0190002 | 3,300 | Ground water | 7 | Below the study levels |
| TOWN OF THURMONT | MD0100023 | 6,200 | Groundwater under influence of surface water | 3 | Reached a study level |
| TOWN OF WALKERSVILLE | MD0100025 | 8,440 | Groundwater under influence of surface water | 1 | Below the study levels |
| U.S. NAVAL ACADEMY | MD0020042 | 8,700 | Ground water | 1 | Below the study levels |
| WALDORF - CHARLES COUNTY DPW | MD0080049 | 84,296 | Surface water purchased | 18 | Below the study levels |
| WASHINGTON SUBURBAN SANITARY COMMISSION | MD0150005 | 1,900,000 | Surface water | 2 | Below the study levels |
| WHITE PLAINS 2 MHP/JACK BLAIR | MD0080208 | 70 | Ground water | 1 | Below the study levels |
How the count works
What is included
Each active community water system with complete monitoring is counted once, even if it is linked with several ZIP codes. Private wells are excluded, and UCMR 5 did not comprehensively monitor every small system. This page does not apply Maryland's state-specific standards or determine compliance. Use the official state or territory drinking-water program for current regulatory information.