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WaterSafeCheck
Official EPA SDWIS Statewide AnalysisState Water Quality & Testing Directory

Illinois Drinking Water Quality & Testing Directory

Comprehensive EPA compliance records, water testing guidelines, and city rankings covering all 1,583 ZIP codes across Illinois

Quick Summary: Is Tap Water Safe in Illinois?

Drinking water in Illinois receives an average composite safety score of 61.3/100 based on EPA Safe Drinking Water Act records. Approximately 1% of monitored ZIP codes earn an "A" grade. Water sources are 48.6% surface water and 51.4% groundwater, resulting in Hard to Very Hard mineral hardness across the state.

Total ZIP Codes

1,583

Health Violations (5yr)

752

Statewide Avg Score

61.3/100

High Lead Risk Areas

76.4%

Overview: Drinking Water in Illinois

Drinking water quality in Illinois averages a composite safety score of 61.3/100 across its 1,583 monitored ZIP codes. Approximately 1% of ZIP codes in the state receive an "A" grade, while 5% receive an "F" grade. Environmental standards are enforced by Illinois Environmental Protection Agency.

Surface Water

48.6%

of ZIP codes

Total Violations

7,431

5-year record

Grade A ZIPs

9

1% of state

Grade F ZIPs

79

5% of state

Water Quality Grade Distribution in Illinois

How do Illinois's 1,583 ZIP codes stack up by water quality grade?

A
9 ZIP codes1%
B
440 ZIP codes28%
C
653 ZIP codes41%
D
402 ZIP codes25%
F
79 ZIP codes5%

Popular Cities in Illinois

Click any city to view ZIP code-level water quality reports

Chicago

86 ZIPs

C

Springfield

38 ZIPs

D

Peoria

29 ZIPs

F

Rockford

14 ZIPs

F

Aurora

10 ZIPs

F

Carol Stream

8 ZIPs

B

Bloomington

8 ZIPs

C

Palatine

7 ZIPs

D

Schaumburg

7 ZIPs

B

East Saint Louis

7 ZIPs

D

Evanston

6 ZIPs

B

Joliet

6 ZIPs

D

Naperville

6 ZIPs

B

Champaign

6 ZIPs

C

Decatur

6 ZIPs

C

Belleville

5 ZIPs

B

Des Plaines

4 ZIPs

B

Elgin

4 ZIPs

F

Oak Park

4 ZIPs

B

Loves Park

4 ZIPs

C

Arlington Heights

3 ZIPs

B

Crystal Lake

3 ZIPs

C

Waukegan

3 ZIPs

C

Melrose Park

3 ZIPs

C

Hoffman Estates

3 ZIPs

B

Plainfield

3 ZIPs

B

Rock Island

3 ZIPs

C

Pekin

3 ZIPs

C

Urbana

3 ZIPs

C

Quincy

3 ZIPs

C

Carbondale

3 ZIPs

B

Elk Grove Village

2 ZIPs

C

Barrington

2 ZIPs

C

Glenview

2 ZIPs

D

Libertyville

2 ZIPs

D

Mchenry

2 ZIPs

C

Northbrook

2 ZIPs

D

North Chicago

2 ZIPs

B

Skokie

2 ZIPs

D

Bensenville

2 ZIPs

B

City A-Z Directory — Illinois

Browse water quality reports for every town and city in Illinois.

A
AbingdonAdairAddievilleAddisonAlbanyAlbersAlbionAldenAledoAlexanderAlexisAlgonquinAlhambraAllendaleAllertonAlmaAlphaAlseyAlsipAltamontAlto PassAltonAltonaAlvinAmboyAnchorAnconaAndalusiaAndoverAnnaAnnapolisAnnawanAntiochApple RiverArcolaArenzvilleArgentaArlingtonArlington HeightsArmingtonArmstrongAroma ParkArrowsmithArthurAshkumAshlandAshleyAshmoreAshtonAssumptionAstoriaAthensAtkinsonAtlantaAtwoodAuburnAugustaAuroraAvaAvistonAvon
B
BaileyvilleBaldwinBardolphBarnhillBarringtonBarryBarstowBartelsoBartlettBascoBataviaBatchtownBathBaylisBeardstownBeasonBeavervilleBeckemeyerBedford ParkBeecherBeecher CityBelknapBelle RiveBellevilleBellflowerBellmontBellwoodBelvidereBementBenldBensenvilleBensonBentonBerkeleyBerwickBerwynBethaltoBethanyBig RockBiggsvilleBinghamBishop HillBismarckBlackstoneBlandinsvilleBloomingdaleBloomingtonBlue IslandBlue MoundBluff SpringsBluffsBlufordBolesBolingbrookBondvilleBone GapBonfieldBonnieBoodyBourbonnaisBowenBracevilleBradfordBradleyBraidwoodBreeseBridgeportBridgeviewBrightonBrimfieldBristolBroadlandsBroadviewBroctonBrookfieldBrookportBroughtonBrowningBrownsBrownstownBrusselsBryantBuckinghamBuckleyBucknerBudaBuffaloBuffalo GroveBuffalo PrairieBulpittBuncombeBunker HillBurbankBureauBurlingtonBurnt PrairieBushnellButlerByron
C
CaberyCairoCaledoniaCalhounCalumet CityCamargoCambriaCambridgeCamdenCameronCamp GroveCamp PointCampbell HillCampusCantonCantrallCapronCarbon CliffCarbondaleCarlinvilleCarlockCarlyleCarmanCarmiCarol StreamCarpentersvilleCarrier MillsCarrolltonCartervilleCarthageCaryCaseyCaseyvilleCastletonCatlinCave In RockCedar PointCedarvilleCentraliaCerro GordoChadwickChambersburgChampaignChanaChandlervilleChannahonChapinCharlestonChathamChatsworthChebanseChenoaCherryCherry ValleyChesterChesterfieldChestnutChicagoChicago HeightsChicago RidgeChillicotheChrismanChristopherCiceroCiscoCisneCissna ParkClareClaremontClarendon HillsClay CityClaytonClaytonvilleCliftonClintonCoal CityCoal ValleyCoatsburgCobdenCoelloCoffeenColchesterColfaxCollinsvilleCollisonColonaColpColumbiaColusaComptonConcordCongervilleCooksvilleCordovaCornellCornlandCortlandCottage HillsCoultervilleCountry Club HillsCowdenCreal SpringsCrescent CityCrest HillCrestonCrestwoodCreteCreve CoeurCropseyCrossvilleCrystal LakeCubaCullomCutlerCypress
D
DahindaDahlgrenDakotaDaleDallas CityDalton CityDalzellDanaDanforthDanversDanvilleDarienDavisDavis JunctionDawsonDe LandDe SotoDecaturDeer CreekDeer GroveDeerfieldDekalbDelavanDennisonDepueDes PlainesDeweyDewittDieterichDivernonDixDixonDoltonDongolaDonnellsonDonovanDorseyDoverDowDowellDowners GroveDownsDu BoisDu QuoinDundasDundeeDunfermlineDunlapDupoDurandDwight
E
EagarvilleEarlvilleEast AltonEast CarondeletEast DubuqueEast GalesburgEast LynnEast MolineEast PeoriaEast Saint LouisEastonEddyvilleEdelsteinEdgewoodEdinburgEdwardsEdwardsvilleEffinghamEl PasoElburnEldenaEldoradoEldredEleroyElginElizabethElizabethtownElk Grove VillageElkhartElkvilleElleryElliottEllis GroveEllisvilleEllsworthElmhurstElmwoodElmwood ParkElsahElvastonElwinElwoodEmdenEmingtonEmmaEnergyEnfieldEolaEqualityErieEsmondEssexEurekaEvanstonEvansvilleEvergreen ParkEwing
F
FairburyFairfieldFairmountFairviewFairview HeightsFarinaFarmer CityFarmersvilleFarmingtonFentonFerrisFiattFidelityFieldonFillmoreFindlayFisherFithianFlanaganFlat RockFloraFlossmoorFooslandForest CityForest ParkForrestForrestonForsythFort SheridanFowlerFox LakeFox River GroveFox ValleyFrankfortFrankfort HeightsFranklinFranklin GroveFranklin ParkFrederickFreeburgFreeman SpurFreeportFultonFults
G
GalatiaGalenaGalesburgGaltGalvaGarden PrairieGardnerGaysGeffGeneseoGenevaGenoaGeorgetownGerlawGerman ValleyGermantownGibson CityGiffordGilbertsGillespieGilmanGilsonGirardGladstoneGlasfordGlen CarbonGlen EllynGlenarmGlencoeGlendale HeightsGlenviewGlenwoodGodfreyGolcondaGoldenGolden EagleGolden GateGolfGood HopeGoodfieldGoodwineGorevilleGorhamGraftonGrand ChainGrand RidgeGrand TowerGranite CityGrant ParkGrantsburgGranvilleGraymontGrayslakeGrayvilleGreat LakesGreen ValleyGreenfieldGreenupGreenviewGreenvilleGridleyGriggsvilleGrovelandGurnee
H
HagarstownHamburgHamelHamiltonHammondHampshireHamptonHanna CityHanoverHanover ParkHardinHarmonHarrisburgHarristownHartfordHartsburgHarvardHarvelHarveyHarwood HeightsHavanaHazel CrestHebronHeckerHendersonHennepinHenningHenryHerodHerrickHerrinHerscherHettickHeyworthHickory HillsHidalgoHighlandHighland ParkHighwoodHillsboroHillsdaleHillsideHillviewHinckleyHindsboroHinesHinsdaleHoffmanHoffman EstatesHolcombHomerHomer GlenHometownHomewoodHoopestonHooppoleHopedaleHopkins ParkHoyletonHudsonHueyHullHumboldtHumeHuntleyHuntsvilleHurstHutsonville
I
Illinois CityIlliopolisInaIndianolaIndustryInglesideIngrahamIpavaIroquoisIrvingIrvingtonIsland LakeItascaIukaIvesdale
J
JacksonvilleJacobJanesvilleJerseyvilleJewettJohnsonvilleJohnston CityJolietJonesboroJoppaJoyJunctionJustice
K
KampsvilleKaneKanevilleKankakeeKansasKarbers RidgeKarnakKasbeerKeenesKeensburgKeithsburgKellKemptonKenilworthKenneyKentKewaneeKeyesportKilbourneKincaidKinderhookKingstonKingston MinesKinmundyKinsmanKirklandKirkwoodKnoxville
L
La FayetteLa GrangeLa Grange ParkLa HarpeLa MoilleLa PlaceLa PrairieLa RoseLa SalleLaconLaddLafoxLake BluffLake ForestLake ForkLake In The HillsLake VillaLake ZurichLakewoodLanarkLancasterLaneLansingLathamLauraLawndaleLawrencevilleLe RoyLeaf RiverLebanonLeeLee CenterLelandLemontLenaLenzburgLeonoreLernaLewistownLexingtonLibertyLibertyvilleLimaLincolnLincolns New SalemLincolnshireLincolnwoodLindenwoodLisleLitchfieldLiterberryLittle YorkLittletonLiverpoolLivingstonLoamiLockportLodaLoganLomaxLombardLondon MillsLong PointLongviewLoraineLostantLouisvilleLovejoyLoves ParkLovingtonLowderLowpointLudlowLyndonLynn CenterLyons
M
MacedoniaMachesney ParkMackinawMacombMaconMadisonMaeystownMagnoliaMahometMakandaMaldenMaltaManchesterManhattanManitoManliusMansfieldMantenoMaple ParkMapletonMaquonMarengoMariettaMarineMarionMarissaMarkMarkhamMaroaMarseillesMarshallMartinsvilleMartintonMaryvilleMascoutahMasonMason CityMathervilleMattesonMattoonMaunieMaywoodMazonMc ClureMc ConnellMc LeanMc LeansboroMc NabbMchenryMechanicsburgMediaMedinahMedoraMelrose ParkMelvinMenardMendonMendotaMeredosiaMernaMetamoraMetcalfMetropolisMichaelMiddletownMidlothianMilanMilfordMill ShoalsMillbrookMillcreekMilledgevilleMiller CityMillingtonMillstadtMilmineMiltonMineralMinierMinonkMinookaModeModestoModocMokenaMolineMomenceMoneeMonmouthMonroe CenterMontgomeryMonticelloMontroseMooseheartMoroMorrisMorrisonMorrisonvilleMortonMorton GroveMossvilleMound CityMoundsMount AuburnMount CarmelMount CarrollMount ErieMount MorrisMount OliveMount ProspectMount PulaskiMount SterlingMount VernonMoweaquaMozierMt ZionMuddyMulberry GroveMulkeytownMuncieMundeleinMurdockMurphysboroMurrayville
N
NachusaNapervilleNashvilleNasonNational Stock YardsNauvooNeboNeogaNeponsetNew AthensNew BadenNew BedfordNew BerlinNew BostonNew BurnsideNew CantonNew DouglasNew HavenNew HollandNew LenoxNew MemphisNew SalemNew WindsorNewarkNewmanNewtonNianticNilesNilwoodNiotaNobleNokomisNoraNormalNorrisNorris CityNorth AuroraNorth ChicagoNorth HendersonNorthbrook
O
O FallonOak BrookOak ForestOak LawnOak ParkOakdaleOakfordOaklandOakwoodOblongOconeeOdellOdinOgdenOglesbyOhioOhlmanOkawvilleOlive BranchOlmstedOlneyOlympia FieldsOmahaOnargaOneidaOpdykeOphiemOquawkaOrangevilleOravilleOreanaOregonOrientOrionOrland ParkOscoOswegoOttawaOwanecoOzark
P
PalatinePalestinePalmerPalmyraPalomaPalos HeightsPalos HillsPalos ParkPanaPanamaPapineauParisPark ForestPark RidgeParkersburgPatokaPattersonPaw PawPawneePaxtonPaysonPearlPearl CityPecatonicaPekinPembroke TownshipPenfieldPeoriaPeoria HeightsPeotonePercyPerksPerryPeruPesotumPetersburgPhiloPiasaPierronPinckneyvillePiper CityPittsburgPittsfieldPlainfieldPlainvillePlanoPleasant HillPleasant PlainsPlymouthPocahontasPoloPomonaPontiacPoplar GrovePort ByronPosenPotomacPrairie CityPrairie Du RocherPreemptionPrincetonPrincevilleProphetstownProspect HeightsPulaskiPutnam
Q
Quincy
R
RadomRaleighRamseyRankinRansomRantoulRapids CityRaritanRaymondRed BudReddickRedmonRenaultReynoldsRichmondRichton ParkRichviewRidge FarmRidgwayRidottRinardRingwoodRioRiver ForestRiver GroveRiverdaleRiversideRivertonRoanokeRobbinsRobertsRobinsonRochelleRochesterRock CityRock FallsRock IslandRockbridgeRockfordRockportRocktonRockwoodRolling MeadowsRomeRomeovilleRoodhouseRosamondRoscoeRoselleRosevilleRosiclareRossvilleRound LakeRoxanaRoyalRoyaltonRushvilleRussellRutland
S
SadorusSailor SpringsSaint AnneSaint AugustineSaint CharlesSaint DavidSaint ElmoSaint FrancisvilleSaint JacobSaint JosephSaint LiborySaint PeterSainte MarieSalemSan JoseSandovalSandwichSauneminSavannaSavoySawyervilleSaybrookScales MoundSchaumburgSchellerSchiller ParkSciotaScott Air Force BaseScottvilleSeatonSeatonvilleSecorSenecaSerenaSesserSewardSeymourShabbonaShannonShawneetownSheffieldShelbyvilleSheldonSheridanShermanSherrardShipmanShirlandShirleyShobonierShorewoodShumwaySibleySidellSidneySigelSilvisSimpsonSimsSkokieSmithboroSmithfieldSmithshireSmithtonSomonaukSorentoSouth BeloitSouth ElginSouth HollandSouth PekinSouth RoxanaSouth WilmingtonSparlandSpartaSpeerSpring GroveSpring ValleySpringertonSpringfieldStandardStanfordStauntonSteelevilleStegerSterlingStewardStewardsonStillman ValleyStocklandStocktonStone ParkStonefortStoningtonStoyStrasburgStrawnStreamwoodStreatorStronghurstSubletteSugar GroveSullivanSummerfieldSummit ArgoSumnerSutterSycamore
T
Table GroveTallulaTamaroaTammsTampicoTaylor RidgeTaylor SpringsTaylorvilleTechnyTennesseeTeutopolisTexicoThawvilleThayerThebesThomasboroThompsonvilleThomsonThorntonTildenTiltonTimewellTinley ParkTiskilwaToledoTolonoTolucaTonicaTopekaToulonToveyTowandaTower HillTremontTrentonTrillaTriumphTrivoliTroyTroy GroveTuscola
U
UllinUnionUnion HillUnityUniversity ParkUrbanaUrsaUtica
V
ValierValmeyerVan OrinVandaliaVarnaVeniceVergennesVermilionVermontVernonVernon HillsVeronaVersaillesVictoriaViennaVilla GroveVilla ParkVilla RidgeViolaVirdenVirginia
W
WadsworthWaggonerWalnutWalnut HillWalshWalshvilleWaltonvilleWapellaWarrenWarrensburgWarrenvilleWarsawWascoWashburnWashingtonWatagaWaterlooWatermanWatsekaWatsonWaucondaWaukeganWaverlyWayneWayne CityWaynesvilleWedronWeldonWellingtonWenonaWest BrooklynWest ChicagoWest FrankfortWest LibertyWest PointWest SalemWest UnionWest YorkWestchesterWestern SpringsWestfieldWestmontWestvilleWheatonWheelerWheelingWhite HallWhite HeathWhittingtonWilliamsfieldWilliamsvilleWillisvilleWillow HillWillow SpringsWillowbrookWilmetteWilmingtonWilsonvilleWinchesterWindsorWinfieldWinnebagoWinnetkaWinslowWinthrop HarborWittWolf LakeWonder LakeWood DaleWood RiverWoodhullWoodlandWoodlawnWoodridgeWoodsonWoodstockWoosungWordenWorthWrightsWyanetWyoming
X
Xenia
Y
YaleYates CityYorkville
Z
ZeiglerZion

🏆 Highest Rated ZIP Codes in Illinois

62953Joppa
94/100
A
62992Ullin
93/100
A
62976Pulaski
91/100
A
60552Somonauk
87/100
A
61370Tonica
87/100
A

⚠ Lowest Rated ZIP Codes in Illinois

61484Vermont
13/100
F
61604Peoria
22/100
F
61614Peoria
22/100
F
61615Peoria
22/100
F
61450La Harpe
23/100
F

Common Drinking Water Contaminants in Illinois

The following are common regulated contaminants found in Illinois drinking water based on EPA violation records. Click any contaminant to learn about EPA safety limits and health effects.

Stage 2 DBP RuleGross BetaStage 1 DBP RuleHaloacetic Acids (HAA5)Total Trihalomethanes (TTHM)ChloriteBariumFecal Coliform

Source: EPA Safe Drinking Water Act Maximum Contaminant Level regulations. For the complete list of regulated contaminants and MCLs, see the Water Quality Safety Guide.

Frequently Asked Questions — Illinois Drinking Water

Is tap water generally safe to drink in Illinois?+
Yes, for the majority of residents, tap water in Illinois is treated and regulated. However, compliance varies by city. State-wide, 9 ZIP codes receive an "A" grade, while 79 receive an "F". Search your specific ZIP code to see your local utility's record.
How do I test water quality or well water in Illinois?+
Residents in Illinois can test their tap or well water by contacting laboratories certified by Illinois Environmental Protection Agency or ordering an EPA-standard laboratory water testing kit. Annual testing is recommended for private wells to test for bacteria, nitrates, and heavy metals.
What are the biggest water quality issues in Illinois?+
The primary issues include managing 752 health-based violations state-wide and resolving infrastructure age. 76.4% of ZIP codes in the state have a high probability of lead exposure risk due to pre-1986 piping.
Who regulates and enforces drinking water standards in Illinois?+
Drinking water in Illinois is regulated by Illinois Environmental Protection Agency under a primacy agreement with the U.S. EPA.
Where does Illinois get its drinking water?+
Approximately 48.6% of monitored areas in Illinois rely on surface water sources (lakes/rivers), while the rest use groundwater aquifers.
How do I find the official water quality report for my home in Illinois?+
Search your ZIP code on our site to view data compiled from EPA records, or contact your local utility for their annual Consumer Confidence Report (CCR).
View All 1,583 ZIP Codes in Illinois

Browse EPA water quality data for every monitored ZIP code. For faster results, use the search bar above.

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All 1,583 ZIP codes in Illinois are actively monitored under the EPA Safe Drinking Water Act.