Maryland tap water quality
460 community water systems serving 5.5 million people.
Data: U.S. EPA · How we read the data · How we check it
13
systems with PFAS above a federal limit
162,211
people served by them
76
systems EPA tested for PFAS
1
systems above the lead action level
PFAS: EPA's 2023–2025 testing. Lead: results from the last five years. 54 more systems have no recent lead results in EPA's database.
Water systems with PFAS above the federal limit
Based on EPA's UCMR 5 results (2023–2025) compared to the April 2024 limits, the way EPA compares them. Systems have until 2029 to comply. Largest first.
- City of Westminster35,256 people · Surface water · MarylandPFOA above limitAlso: PFOS above limit · Total trihalomethanes (TTHM) violations · PFHxS detected
- City of Salisbury30,343 people · Groundwater · MarylandPFOS above limitAlso: PFOA detected · PFHxS detected
- City of Aberdeen18,006 people · Purchased surface water · MarylandPFOA above limitAlso: PFOS above limit · PFHxS detected
- Town of Elkton15,625 people · Surface water · MarylandPFOA above limitAlso: PFOS above limit · PFHxS detected · 2 health-based violations since 2016
- Maryland American Water13,200 people · Surface water · MarylandPFOA above limitAlso: PFOS above limit · PFHxS detected
- Town of Mount Airy9,890 people · Groundwater · MarylandPFOA above limitAlso: PFOS above limit
- City of Taneytown6,750 people · Groundwater · MarylandPFOA above limitAlso: PFOS above limit · PFHxS detected · Lithium above screening level
- Town of Hampstead6,600 people · Groundwater · MarylandPFOA above limitAlso: PFOS above limit · PFHxS detected
- Town of Thurmont6,200 people · Groundwater under influence of surface water · MarylandPFOA above limitAlso: PFOS above limit · PFHxS detected
- Town of Poolesville6,005 people · Groundwater under influence of surface water · MarylandPFOA above limitAlso: PFOS above limit · PFHxS detected · Lithium above screening level
- Town of Middletown5,132 people · Groundwater · MarylandPFOA above limitAlso: PFOS above limit · PFHxS detected
- Town of Manchester4,954 people · Groundwater · MarylandPFOA above limitAlso: PFHxS detected
- Boonsboro – Keedysville Water System4,250 people · Surface water · MarylandPFOA above limitAlso: PFHxS detected
Maryland PFAS report: chart, rankings and data to download →
Largest water systems in Maryland
- Washington Suburban Sanitary Commission1.9 million people · Surface water · MarylandNo PFAS above limits
- City of Baltimore1.6 million people · Surface water · MarylandTotal trihalomethanes (TTHM) violationsAlso: Coliform bacteria violation · Haloacetic acids (HAA5) violation
- Glen Burnie-Broadneck Water System290,606 people · Groundwater · MarylandNo PFAS above limits
- Howard County Dept. of Public Works Distribution286,158 people · Purchased surface water · MarylandNo PFAS above limits
- Harford County Dept. of Public Works104,567 people · Surface water · MarylandNo PFAS above limits
- City of Hagerstown92,200 people · Surface water · MarylandNo PFAS above limits
- Waldorf – Charles County Dept. of Public Works84,296 people · Purchased surface water · MarylandNo PFAS above limits
- New Design – Frederick County Water System74,911 people · Surface water · MarylandNo PFAS above limits
- Crofton-Odenton Water System62,986 people · Groundwater · MarylandNo PFAS above limits
- Fort George G. Meade Water System62,234 people · Groundwater · MarylandNo PFAS above limits
- City of Frederick54,000 people · Surface water · MarylandNo PFAS above limits
- City of Rockville52,000 people · Surface water · MarylandNo PFAS above limits
- Lexington Park Water System43,030 people · Groundwater · MarylandNo PFAS above limits
- City of Westminster35,256 people · Surface water · MarylandPFOA above limitAlso: PFOS above limit · Total trihalomethanes (TTHM) violations · PFHxS detected
- City of Annapolis35,000 people · Groundwater · MarylandNo PFAS above limits
Maryland cities and towns
Most health-based violations since 2016
- Springfield Hospital Distribution Water System1,500 people · Purchased surface water · MarylandHaloacetic acids (HAA5) violationsAlso: Total trihalomethanes (TTHM) violations
- Town of North East8,600 people · Surface water · MarylandHaloacetic acids (HAA5) violationsAlso: Total trihalomethanes (TTHM) violations
- Town of Perryville4,413 people · Surface water · MarylandTotal trihalomethanes (TTHM) violationsAlso: Haloacetic acids (HAA5) violations
- City of Pocomoke City4,100 people · Groundwater · MarylandTotal trihalomethanes (TTHM) violations
- Perry Point V.A. Medical Center Water System2,000 people · Surface water · MarylandHaloacetic acids (HAA5) violationsAlso: Total trihalomethanes (TTHM) violations
- Freedom District24,867 people · Surface water · MarylandTotal trihalomethanes (TTHM) violationsAlso: Haloacetic acids (HAA5) violations
- Golden Kay Apartments Water System148 people · Groundwater · MarylandRadium (combined 226/228) violations
- City of Havre de Grace14,000 people · Surface water · MarylandTotal trihalomethanes (TTHM) violations
- Reliance Mobile Home Park Water System200 people · Groundwater · MarylandNitrate violationAlso: Coliform bacteria violation
- Tebbston on Magothy Water System52 people · Groundwater · MarylandNot in EPA's PFAS sampleAlso: 5 health-based violations since 2016
- Liberty Mobile Home Park40 people · Groundwater · MarylandNitrate violations
- Meadowbrook Court Water System50 people · Groundwater · MarylandColiform bacteria violations
- Town of Snow Hill2,409 people · Groundwater · MarylandTotal trihalomethanes (TTHM) violations
- City of Baltimore1.6 million people · Surface water · MarylandTotal trihalomethanes (TTHM) violationsAlso: Coliform bacteria violation · Haloacetic acids (HAA5) violation
- City of Westminster35,256 people · Surface water · MarylandPFOA above limitAlso: PFOS above limit · Total trihalomethanes (TTHM) violations · PFHxS detected
All Maryland utilities on this site
Every Maryland system serving 50,000+ people or with PFAS above a federal limit, A to Z. Download all 460 systems as CSV.
- Boonsboro – Keedysville Water System
- City of Aberdeen
- City of Baltimore
- City of Frederick
- City of Hagerstown
- City of Rockville
- City of Salisbury
- City of Taneytown
- City of Westminster
- Crofton-Odenton Water System
- Fort George G. Meade Water System
- Glen Burnie-Broadneck Water System
- Harford County Dept. of Public Works
- Howard County Dept. of Public Works Distribution
- Maryland American Water
- New Design – Frederick County Water System
- Town of Elkton
- Town of Hampstead
- Town of Manchester
- Town of Middletown
- Town of Mount Airy
- Town of Poolesville
- Town of Thurmont
- Waldorf – Charles County Dept. of Public Works
- Washington Suburban Sanitary Commission
Questions
Does Maryland tap water have PFAS?
EPA tested 76 community water systems in Maryland for 29 PFAS between 2023 and 2025. 15 had at least one regulated PFAS detected, and 13 had an entry-point average above a 2024 federal limit. Those 13 systems serve about 162,211 people (3% of people on community water in Maryland). Systems have until 2029 to meet the limits.
How many Maryland water systems have violations?
157 systems in Maryland had at least one health-based violation since 2016 (281 violations in total). 47 violations are currently listed as unaddressed.
Which Maryland water systems are over the lead action level?
1 system had a lead 90th percentile above the 15 ppb action level in their most recent results from the last five years. Another 54 systems have no lead results in EPA's database from the last five years, including 2 whose last result was above the action level. Lead depends on each home's pipes, so a test of your own tap is the only way to know your level.
Source: U.S. EPA drinking water records and PFAS testing (UCMR 5). How we read the data.