Iowa tap water quality

1,083 active community water systems.

Largest water systems

GradeSystemPeopleHealth violations (5y)
ADes Moines Water Works246,0550
AIowa-American WTR Co-Davenport147,7200
ACedar Rapids Water Department142,3640
BSioux City Water Supply85,7910
ACity of Ankeny76,2070
AWest Des Moines Water Works73,9590
BWaterloo Water Works69,5040
AIowa City Water Department68,7530
ACouncil Bluffs Water Works64,4470
ADubuque Water Works59,6670
AAmes Water Treatment Plant55,1770
AUniversity Water System47,1360
AUrbandale Water Utility45,6050
AIsu42,0000
AMarion Municipal Water Dept41,6230
ACedar Falls Municipal Water Utilities40,7130
AIA Regional Utilities Assoc (Waverly)37,8200
ARathbun Regional Water Assn (Rathbun)33,0000
AWaukee Water Supply31,8230
AMarshalltown Water Works27,6800
AMason City Water Department27,3380
ABurlington Municipal Waterworks26,0150
AFort Dodge Water Supply25,8740
AOttumwa Water Works25,5290
AMuscatine Power & Water25,5160
AJohnston Municipal Water Supply24,8970
AIowa-American WTR Co-Clinton District24,7690
ANorth Liberty Water Supply23,2760
BAltoona Water Supply22,4361
ACoralville Muni Water System22,3180
ASirwa #2 (Creston)20,7930
AClive Water Department20,2770
AWarren Water District20,0950
AGrimes Water Supply17,9970
AWapello Rural Water Assoc.17,2630
ANewton Water Supply16,5180
AIndianola Water Supply15,8330
ANorwalk Water Supply14,3340
APoweshiek Water Association13,9200
AXenia Rwd (Des Moines)12,8600
AOskaloosa Municipal Water Dept12,8080
CBoone Water Works12,7042
ARathbun Reg Water Assn (Ft Madison)11,8400
AStorm Lake Water Treatment Plant11,4310
ASpencer Municipal Water Utility11,3250
AMahaska Rural Water System, Inc.11,3250
AFt Madison Muni Water Works11,0870
APella Water Works Department11,0520
ALemars Water Department10,6060
AWaverly Water Department10,3940

Most issues (systems serving 10,000+)

C

Boone Water Works

Serves 12,704 people · Surface water · Full report →
2 health-based violations in the last 5 years; PFAS tested (UCMR 5), none above federal limits; Lead 90th percentile below the action level (2025).
B

Sioux City Water Supply

Serves 85,791 people · Surface water · Full report →
No health-based violations in the last 5 years; 2 monitoring/reporting violations; Other PFAS above 2024 limits (rule proposed for repeal): PFHxS, Hazard Index; Lead 90th percentile below the action level (2025).
B

Altoona Water Supply

Serves 22,436 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; Lead 90th percentile below the action level (2025).
B

Waterloo Water Works

Serves 69,504 people · Groundwater · Full report →
No health-based violations in the last 5 years; Other PFAS above 2024 limits (rule proposed for repeal): PFHxS, Hazard Index; Lead 90th percentile below the action level (2025).
A

Ottumwa Water Works

Serves 25,529 people · Surface water · 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 (2025).
A

Waverly Water Department

Serves 10,394 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 (2023).
A

Oskaloosa Municipal Water Dept

Serves 12,808 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; Lead 90th percentile below the action level (2025).
A

Ames Water Treatment Plant

Serves 55,177 people · Groundwater · Full report →
No health-based violations in the last 5 years; 1 monitoring/reporting violation; PFAS tested (UCMR 5), none above federal limits; Lead 90th percentile below the action level (2025).
A

Isu

Serves 42,000 people · Groundwater · Full report →
No health-based violations in the last 5 years; 1 monitoring/reporting violation; PFAS tested (UCMR 5), none above federal limits; Lead 90th percentile below the action level (2024).
A

Mason City Water Department

Serves 27,338 people · Groundwater · Full report →
No health-based violations in the last 5 years; 1 monitoring/reporting violation; PFAS tested (UCMR 5), none above federal limits; Lead 90th percentile below the action level (2023).
A

Fort Dodge Water Supply

Serves 25,874 people · Groundwater · Full report →
No health-based violations in the last 5 years; 1 monitoring/reporting violation; PFAS tested (UCMR 5), none above federal limits; Lead 90th percentile below the action level (2025).
A

Des Moines Water Works

Serves 246,055 people · Surface water · Full report →
No health-based violations in the last 5 years; PFAS tested (UCMR 5), none above federal limits; Lead 90th percentile below the action level (2024).
A

Iowa-American WTR Co-Davenport

Serves 147,720 people · Surface water · Full report →
No health-based violations in the last 5 years; PFAS tested (UCMR 5), none above federal limits; Lead 90th percentile below the action level (2024).
A

Cedar Rapids Water Department

Serves 142,364 people · Surface water · Full report →
No health-based violations in the last 5 years; PFAS tested (UCMR 5), none above federal limits; Lead 90th percentile below the action level (2025).
A

City of Ankeny

Serves 76,207 people · Surface water · Full report →
No health-based violations in the last 5 years; PFAS tested (UCMR 5), none above federal limits; Lead 90th percentile below the action level (2025).
A

West Des Moines Water Works

Serves 73,959 people · Surface water · Full report →
No health-based violations in the last 5 years; PFAS tested (UCMR 5), none above federal limits; Lead 90th percentile below the action level (2023).
A

Iowa City Water Department

Serves 68,753 people · Surface water · Full report →
No health-based violations in the last 5 years; PFAS tested (UCMR 5), none above federal limits; Lead 90th percentile below the action level (2023).
A

Council Bluffs Water Works

Serves 64,447 people · Surface water · Full report →
No health-based violations in the last 5 years; PFAS tested (UCMR 5), none above federal limits; Lead 90th percentile below the action level (2023).
A

Dubuque Water Works

Serves 59,667 people · Groundwater · Full report →
No health-based violations in the last 5 years; PFAS tested (UCMR 5), none above federal limits; Lead 90th percentile below the action level (2023).
A

University Water System

Serves 47,136 people · Surface water · Full report →
No health-based violations in the last 5 years; PFAS tested (UCMR 5), none above federal limits; Lead 90th percentile below the action level (2024).

Cities

AckleyAckworthAdairAdelAftonAgencyAinsworthAkronAlbert CityAlbiaAlbionAlburnettAldenAlexanderAlgonaAllemanAllertonAllisonAltaAlta VistaAltonAltoonaAlvordAmanaAmesAnamosaAndoverAndrewAnitaAnkenyAnthonAplingtonArcadiaArcherArgyleArispeArlingtonArmstrongArnolds ParkArthurAsburyAshtonAspinwallAtalissaAtkinsAtlanticAuburnAudubonAureliaAuroraAustinvilleAvocaAyrshireBadgerBagleyBaldwinBancroftBarnes CityBarnumBataviaBattle CreekBaxterBayardBeaconBeamanBeaverBedfordBelle PlaineBellevueBelmondBennettBentonBernardBertramBerwickBettendorfBevingtonBirminghamBlairsburgBlairstownBlakesburgBlanchardBlencoeBlocktonBloomfieldBlue GrassBodeBonaparteBondurantBooneBoonevilleBoutonBoxholmBoydenBraddyvilleBrandonBraytonBredaBridgewaterBrightonBristowBrittBronsonBrooklynBrooksBrunsvilleBuckeyeBuckinghamBuffaloBuffalo CenterBurlingtonBurnsideBurtBusseyCalamusCallenderCalmarCalumetCamancheCambridgeCantrilCarlisleCarrollCarsonCarter LakeCascadeCaseyCastaliaCastanaCedarCedar FallsCedar RapidsCenter JunctionCenter PointCentervilleCentral CityCentraliaCharitonCharles CityCharlotteCharter OakChatsworthChelseaCherokeeChesterChillicotheChurdanCincinnatiClareClarenceClarindaClarionClarksvilleClaytonClear LakeClearfieldCleghornClemonsClermontClintonClioCliveClutierCoggonCoinColesburgColfaxCollege SpringsCollinsColoColumbiaColumbus CityColumbus JunctionColwellConesvilleConradConroyCoon RapidsCoralvilleCorningCorrectionvilleCorwithCorydonCoulterCouncil BluffsCraigCrawfordsvilleCrescentCrescoCrestonCromwellCrystal LakeCumberlandCummingCurlewCushingDakota CityDallas CenterDanaDanburyDanvilleDavenportDavis CityDawsonDaytonDe SotoDe WittDecaturDecatur CityDecorahDedhamDeep RiverDefianceDelawareDelhiDelmarDeloitDeltaDenisonDenmarkDenverDerbyDes MoinesDewarDexterDiagonalDickensDikeDixonDolliverDonahueDonnellsonDoonDoudsDow CityDowsDrakesvilleDubuqueDumontDuncombeDundeeDunkertonDunlapDurantDyersvilleDysartEagle GroveEarlhamEarlingEarlvilleEarlyEddyvilleEdgewoodElberonEldonEldoraEldridgeElginElk HornElk Run HeightsElkaderElkhartElliottEllstonEllsworthElmaElyEmersonEmmetsburgEpworthEssexEsthervilleEvansdaleEverlyExiraExlineFairbankFairfaxFairfieldFarleyFarmersburgFarmingtonFarnhamvilleFarragutFayetteFentonFergusonFertileFlorisFloydFondaFontanelleForest CityFort AtkinsonFort DodgeFort MadisonFostoriaFrankvilleFredericksburgFrederikaFremontFruitlandGalvaGarden CityGarden GroveGarnavilloGarnerGarrisonGarwinGenevaGeorgeGibsonGiffordGilbertGilbertvilleGillett GroveGilmanGilmore CityGladbrookGlenwoodGliddenGoldfieldGoodellGoose LakeGowrieGraettingerGraftonGrand JunctionGrand MoundGrand RiverGrandviewGrangerGranvilleGravityGrayGreeleyGreeneGreenfieldGreenvilleGrimesGrinnellGriswoldGrundy CenterGuthrie CenterGuttenbergHalburHamburgHamiltonHamlinHamptonHancockHanlontownHansellHarcourtHarlanHarperHarrisHartfordHartleyHarveyHastingsHavelockHaverhillHawardenHawkeyeHazletonHedrickHendersonHiawathaHillsHillsboroHintonHollandHolsteinHoly CrossHomesteadHopkintonHornickHospersHoughtonHubbardHudsonHullHumboldtHumestonHuxleyIda GroveImogeneIndependenceIndianolaInwoodIoniaIowa CityIowa FallsIraIretonIrwinJamaicaJanesvilleJeffersonJesupJewellJohnstonJoiceJolleyKalonaKamrarKanawhaKellertonKelleyKelloggKensettKeokukKeosauquaKeotaKesleyKeswickKeystoneKillduffKimballtonKingsleyKirkmanKirkvilleKironKlemmeKnierimKnoxvilleLA MotteLA Porte CityLaconaLadoraLake CityLake MillsLake ParkLake ViewLakesideLakotaLamoniLamontLanesboroLansingLarchwoodLarrabeeLatimerLaurelLaurensLawlerLawtonLe ClaireLe GrandLe MarsLedyardLehighLelandLenoxLeonLesterLewisLiberty CenterLibertyvilleLidderdaleLime SpringsLincolnLindenLinevilleLinn GroveLisbonLiscombLittle RockLittle SiouxLivermoreLockridgeLoganLohrvilleLone RockLone TreeLong GroveLorimorLost NationLoviliaLow MoorLowdenLu VerneLuanaLucasLutherLuverneLuxemburgLuzerneLynnvilleLyttonMacedoniaMacksburgMadridMagnoliaMaharishi Vedic CityMalcomMallardMalvernManchesterManillaManlyManningMansonMapletonMaquoketaMarathonMarble RockMarcusMarengoMarionMarneMarquetteMarshalltownMartelleMartensdaleMason CityMasonvilleMassenaMatlockMauriceMaxwellMay CityMaynardMaysvilleMc CallsburgMc CauslandMc ClellandMcCallsburgMcGregorMechanicsvilleMediapolisMelbourneMelcher DallasMelcher-DallasMelroseMelvinMenloMeridenMerrillMeserveyMiddle AmanaMiddletownMilesMilfordMillersburgMillertonMiloMiltonMinburnMindenMingoMissouri ValleyMitchellvilleModaleMondaminMonmouthMononaMonroeMontezumaMonticelloMontourMontpelierMontroseMoorheadMoorlandMoraviaMorleyMorning SunMorrisonMoultonMount AuburnMount AyrMount PleasantMount SterlingMount UnionMount VernonMovilleMurrayMuscatineMysticNashuaNemahaNeolaNevadaNew AlbinNew HamptonNew HartfordNew LibertyNew LondonNew MarketNew ProvidenceNew SharonNew ViennaNew VirginiaNewellNewhallNewtonNodawayNora SpringsNorth EnglishNorth LibertyNorthboroNorthwoodNorwalkNorwayOaklandOakvilleOcheyedanOdeboltOelweinOgdenOkobojiOldsOlinOllieOnawaOnslowOrange CityOrchardOrientOsageOsceolaOskaloosaOssianOthoOtleyOtoOttosenOttumwaOxfordOxford JunctionOyensPacific JunctionPackwoodPalmerPaloPanamaPanoraParkersburgPatonPaullinaPellaPeostaPerryPershingPersiaPeruPetersonPiersonPilot MoundPisgahPlainfieldPlanoPleasant HillPleasant ValleyPleasantvillePloverPlymouthPocahontasPolk CityPomeroyPortsmouthPostvillePrairie CityPrairieburgPrescottPrestonPrimgharPrincetonProlePromise CityProtivinPulaskiQuasquetonQuimbyRadcliffeRakeRalstonRandallRandolphRaymondReadlynReasnorRed OakReddingRedfieldReinbeckRembrandtRemsenRenwickRhodesRicevilleRichlandRidgewayRinardRingstedRippeyRiversideRivertonRobinsRock RapidsRock ValleyRockfordRockwellRockwell CityRodmanRolandRolfeRomeRose HillRowanRowleyRoyalRuddRunnellsRussellRuthvenRutlandRyanSabulaSac CitySaint AnsgarSaint AnthonySaint CharlesSaint LucasSaint MarysSaint OlafSaint PaulSalemSalixSanbornSchallerSchleswigScrantonSearsboroSelmaSergeant BluffSeymourShambaughShannon CitySharpsburgSheffieldShelbySheldahlSheldonShell RockShellsburgShenandoahSherrillShueyvilleSibleySidneySigourneySilver CitySioux CenterSioux CitySioux RapidsSlaterSloanSmithlandSoldierSolonSomersSouth AmanaSouth EnglishSpencerSperrySpillvilleSpirit LakeSpraguevilleSpringbrookSpringvilleStacyvilleStanhopeStanleyStantonStanwoodState CenterSteamboat RockStockportStocktonStorm LakeStory CityStoutStratfordStrawberry PointStuartSullySumnerSuperiorSutherlandSwaledaleSwanSwea CitySwisherTaborTamaTempletonTerrilThayerThompsonThorThorntonThurmanTiffinTingleyTiptonTitonkaToddvilleToledoTracyTraerTreynorTripoliTruesdaleTruroUdellUnderwoodUnionUnionvilleUniversity ParkUrbanaUrbandaleUteVailVan HorneVan MeterVan WertVarinaVenturaVictorVilliscaVincentViningVintonVolgaVolga CityWadenaWahpetonWalcottWalfordWalkerWall LakeWallingfordWalnutWapelloWashingtonWashtaWaterlooWatkinsWaucomaWaukeeWaukonWaverlyWaylandWebbWebsterWebster CityWeldonWellmanWellsburgWeltonWesleyWest BendWest BranchWest BurlingtonWest ChesterWest Des MoinesWest LibertyWest OkobojiWest PointWest UnionWestfieldWestgateWestphaliaWestsideWestwoodWeverWhat CheerWheatlandWhitingWhittemoreWhittenWilliamsWilliamsburgWilliamsonWilliamstownWiltonWindsor HeightsWinfieldWintersetWinthropWiotaWodenWoodbineWoodburnWoodwardWoolstockWorthingtonWyomingYaleYarmouthYorktownZearing