Maryland tap water quality

460 active community water systems.

Largest water systems

GradeSystemPeopleHealth violations (5y)
AWSSC Water (Washington Suburban Sanitary Commission)1,900,0000
DBaltimore City Department of Public Works1,600,0003
AGlen Burnie-Broadneck290,6060
AHoward County D.P.W. Distribution286,1580
AHarford County D.P.W.104,5670
ACity of Hagerstown92,2000
AWaldorf - Charles County Dpw84,2960
ANew Design - Frederick County74,9110
ACrofton-Odenton62,9860
AFort George G. Meade62,2340
ACity of Frederick54,0000
BCity of Rockville52,0000
ALexington Park43,0300
CCity of Westminster35,2560
ACity of Annapolis35,0000
BCity of Salisbury30,3430
CTown of Ocean City30,0001
ACity of Cumberland27,0390
ABroad Creek26,0330
BCity of Bowie25,0001
AFreedom District24,8670
APatuxent Naval Air Station (Navfac-Wash)22,0000
CCity of Aberdeen18,0060
AEaston Utilities17,3570
DTown of Elkton15,6252
AChapel Hill - Aberdeen Proving Grounds15,0000
ACity of Cambridge Water15,0000
CCity of Havre De Grace14,0001
CMaryland American Water Company13,2000
AOcean Pines11,8900
ATown of LA Plata11,5350
ACity of Frostburg11,0000
CTown of Mount Airy9,8900
AChesapeake Ranch Estates9,5000
AStevensville9,1550
AU.S. Naval Academy8,7000
DTown of North East8,60010
ATown of Walkersville8,4400
BFort Detrick7,9001
ACity of Brunswick7,3120
CCity of Taneytown6,7500
CTown of Hampstead6,6000
ABryans Road6,2600
CTown of Thurmont6,2000
CTown of Poolesville6,0050
AMystic Harbour5,9450
ACity of Fruitland5,9070
AEastern Region Allegany Distrib. System5,7030
ADeep Creek Lake Water Service Area5,5020
ALavale Sanitary Commission5,5000

Most issues (systems serving 10,000+)

D

Town of Elkton

Serves 15,625 people · Surface water · Full report →
2 health-based violations in the last 5 years; 1 monitoring/reporting violation; PFOA/PFOS average above the 4 ppt federal limit: PFOS, PFOA; Lead 90th percentile below the action level (2024).
D

Baltimore City Department of Public Works

Serves 1,600,000 people · Surface water · Full report →
3 health-based violations in the last 5 years; 7 monitoring/reporting violations; PFAS tested (UCMR 5), none above federal limits; Lead 90th percentile below the action level (2024).
C

City of Westminster

Serves 35,256 people · Surface water · Full report →
No health-based violations in the last 5 years; 1 monitoring/reporting violation; PFOA/PFOS average above the 4 ppt federal limit: PFOS, PFOA; Lead 90th percentile below the action level (2024).
C

City of Aberdeen

Serves 18,006 people · Surface water · Full report →
No health-based violations in the last 5 years; PFOA/PFOS average above the 4 ppt federal limit: PFOA, PFOS; Lead 90th percentile below the action level (2023).
C

Maryland American Water Company

Serves 13,200 people · Surface water · Full report →
No health-based violations in the last 5 years; PFOA/PFOS average above the 4 ppt federal limit: PFOS, PFOA; Lead 90th percentile below the action level (2023).
C

City of Havre De Grace

Serves 14,000 people · Surface water · Full report →
1 health-based violation in the last 5 years; 16 monitoring/reporting violations; PFAS tested (UCMR 5), none above federal limits; Lead 90th percentile below the action level (2025).
C

Town of Ocean City

Serves 30,000 people · Groundwater · Full report →
1 health-based violation in the last 5 years; 5 monitoring/reporting violations; PFAS tested (UCMR 5), none above federal limits; Lead 90th percentile below the action level (2024).
B

City of Salisbury

Serves 30,343 people · Groundwater · Full report →
No health-based violations in the last 5 years; PFOA/PFOS average above the 4 ppt federal limit: PFOS; Lead 90th percentile below the action level (2024).
B

City of Bowie

Serves 25,000 people · Groundwater · Full report →
1 health-based violation in the last 5 years; 1 monitoring/reporting violation; PFAS tested (UCMR 5), none above federal limits; Latest lead 90th percentile on file is from 2020 (older than 5 years, not graded).
B

City of Rockville

Serves 52,000 people · Surface water · Full report →
No health-based violations in the last 5 years; 16 monitoring/reporting violations; PFAS tested (UCMR 5), none above federal limits; Latest lead 90th percentile on file is from 2018 (older than 5 years, not graded).
A

Lexington Park

Serves 43,030 people · Groundwater · Full report →
No health-based violations in the last 5 years; 4 monitoring/reporting violations; PFAS tested (UCMR 5), none above federal limits; Lead 90th percentile below the action level (2023).
A

Harford County D.P.W.

Serves 104,567 people · Surface water · Full report →
No health-based violations in the last 5 years; 3 monitoring/reporting violations; PFAS tested (UCMR 5), none above federal limits; Lead 90th percentile below the action level (2023).
A

Waldorf - Charles County Dpw

Serves 84,296 people · Surface water · Full report →
No health-based violations in the last 5 years; 3 monitoring/reporting violations; PFAS tested (UCMR 5), none above federal limits; Lead 90th percentile below the action level (2023).
A

Freedom District

Serves 24,867 people · Surface water · Full report →
No health-based violations in the last 5 years; 3 monitoring/reporting violations; PFAS tested (UCMR 5), none above federal limits; Latest lead 90th percentile on file is from 2020 (older than 5 years, not graded).
A

Patuxent Naval Air Station (Navfac-Wash)

Serves 22,000 people · Groundwater · Full report →
No health-based violations in the last 5 years; 3 monitoring/reporting violations; PFAS tested (UCMR 5), none above federal limits; Lead 90th percentile below the action level (2025).
A

Glen Burnie-Broadneck

Serves 290,606 people · Groundwater · Full report →
No health-based violations in the last 5 years; 2 monitoring/reporting violations; PFAS tested (UCMR 5), none above federal limits; Latest lead 90th percentile on file is from 2018 (older than 5 years, not graded).
A

New Design - Frederick County

Serves 74,911 people · Surface water · Full report →
No health-based violations in the last 5 years; 2 monitoring/reporting violations; PFAS tested (UCMR 5), none above federal limits; Latest lead 90th percentile on file is from 2019 (older than 5 years, not graded).
A

Crofton-Odenton

Serves 62,986 people · Groundwater · Full report →
No health-based violations in the last 5 years; 2 monitoring/reporting violations; PFAS tested (UCMR 5), none above federal limits; Latest lead 90th percentile on file is from 2019 (older than 5 years, not graded).
A

Broad Creek

Serves 26,033 people · Groundwater · Full report →
No health-based violations in the last 5 years; 2 monitoring/reporting violations; PFAS tested (UCMR 5), none above federal limits; Latest lead 90th percentile on file is from 2019 (older than 5 years, not graded).
A

Ocean Pines

Serves 11,890 people · Groundwater · Full report →
No health-based violations in the last 5 years; 2 monitoring/reporting violations; PFAS tested (UCMR 5), none above federal limits; Lead 90th percentile below the action level (2023).

Cities

AbellAberdeenAberdeen Proving GroundAbingdonAccidentAccokeekAdamstownAllenAndrews Air Force BaseAnnapolisAnnapolis JunctionArnoldAshtonBaldwinBaltimoreBarstowBel AirBel AltonBelcampBeltsvilleBenedictBerlinBethesdaBettertonBishopvilleBladensburgBloomingtonBoonsboroBowieBoydsBraddock HeightsBrandywineBrentwoodBrookevilleBrooklynBrunswickBryans RoadBurtonsvilleCabin JohnCaliforniaCallawayCambridgeCapitol HeightsCascadeCatonsvilleCavetownCeciltonCentrevilleCharlestownCharlotte HallChaseCheltenhamChesapeake BeachChesapeake CityChesterChestertownChevy ChaseChewsvilleChildsChurch HillChurchvilleClaiborneClarksburgClear SpringClintonCockeysvilleCollege ParkColoraColumbiaConowingoCrisfieldCroftonCrownsvilleCrumptonCumberlandCurtis BayDamascusDarlingtonDelmarDentonDerwoodDistrict HeightsDowellDundalkDunkirkEarlevilleEast New MarketEastonEdenEdgewaterEdgewoodElk MillsElkridgeElktonEllerslieEllicott CityEmmitsburgEssexEwellFallstonFaulknerFederalsburgFinksburgForest HillForkFort George G MeadeFort HowardFort WashingtonFrederickFriendshipFriendsvilleFrostburgFruitlandFunkstownGaithersburgGalenaGambrillsGarrett ParkGermantownGibson IslandGlen ArmGlen BurnieGlen EchoGlenn DaleGlenwoodGlyndonGrantsvilleGrasonvilleGreat MillsGreenbeltGreensboroGunpowderGwynn OakHagerstownHalethorpeHampsteadHancockHanoverHarmansHavre De GraceHebronHendersonHollywoodHughesvilleHunt ValleyHuntingtownHurlockHyattsvilleHydesIjamsvilleIndian HeadIssueJeffersonJessupJoppaKeedysvilleKennedyvilleKensingtonKingsvilleKitzmillerKnoxvilleLa PlataLanhamLaurelLeonardtownLexington ParkLibertytownLinkwoodLinthicum HeightsLittle OrleansLonaconingLong GreenLothianLukeLusbyLutherville TimoniumManchesterMarburyMardela SpringsMarriottsvilleMarydelMaugansvilleMc HenryMechanicsvilleMiddle RiverMiddletownMidlothianMillersvilleMillingtonMonroviaMontgomery VillageMorganzaMount AiryMount RainierMount SavageMyersvilleNew MarketNew WindsorNewarkNewburgNorth BeachNorth EastNottinghamOaklandOcean CityOdentonOlneyOwingsOwings MillsOxfordOxon HillPark HallParkvilleParsonsburgPasadenaPatuxent RiverPerry HallPerry PointPerrymanPerryvillePhoenixPikesvillePiney PointPittsvillePocomoke CityPoint Of RocksPomfretPoolesvillePort DepositPort RepublicPotomacPrestonPrince FrederickPrincess AnneQueenstownRandallstownRawlingsReisterstownRhodesdaleRiderwoodRidgelyRising SunRivaRiverdaleRock HallRockvilleRohrersvilleRosedaleSaint JamesSaint LeonardSaint Marys CitySaint MichaelsSalisburySandy SpringSavageSecretarySevernSeverna ParkSharpsburgSharptownSilver SpringSmithsburgSnow HillSolomonsSparrows PointSpencervilleStevensonStevensvilleStreetSudlersvilleSuitlandSykesvilleTakoma ParkTall TimbersTaneytownTemple HillsThurmontTilghmanTowsonTrappeTylertonUnion BridgeUpper FairmountUpper FallsUpper MarlboroWaldorfWalkersvilleWashington GroveWelcomeWesternportWestminsterWestoverWhite MarshWhite PlainsWillardsWilliamsportWindsor MillWoodbineWoodsboroWoodstockWorton