How hard is the water in Oregon?

The average water hardness across Oregon is 47 PPM (2.8 GPG), classified as soft. Hardness varies by city - the hardest higher-confidence city page is Harbor (307 PPM) and the softest is Aloha (12 PPM).

What city in Oregon has the hardest water?

Harbor has the hardest water among higher-confidence Oregon city pages at 307 PPM. A water softener is recommended for residents.

How many water systems are in Oregon?

Oregon has 934 active community water systems serving 358 cities.

Water Hardness in Oregon

Average: 47 PPMSoft358 cities934 water systems

State data profile

How to read the Oregon results

State pages are screening and comparison hubs. They summarize ZIP, city, and water-system patterns so you can find the local page that best matches your home or utility.

Direct or USGS-backed ZIPs

251 of 400

63% use treated-water records or USGS monitoring.

Estimated ZIP values

149 ZIPs

37% use nearby, county, or state-level fallback values.

Dataset update

March 9, 2026

Source coverage and rollups are rebuilt from the public dataset.

Use the source coverage below to judge how much local confirmation a specific city or ZIP needs. The methodology page explains the source hierarchy, weighting, and limitations.

State Average

47 PPM

Soft

Coverage

358 cities

934 water systems in the state rollup.

Data Source Coverage

ZIP-level source mix for Oregon; higher direct and USGS coverage means less reliance on regional estimates.

400 ZIPs covered

Verified treated water

Utility, CCR, or state treated-water records

46%

184 ZIPs

High-confidence USGS

Environmental monitoring matched to local systems

17%

67 ZIPs

Estimated

Nearby, county, or state-level fallback values

37%

149 ZIPs

In Oregon, 46% of ZIPs use verified treated-water records, 17% use high-confidence USGS monitoring, and 37% use estimates that should be confirmed locally for treatment decisions.

What the Data Shows in Oregon

Most classified ZIPs in Oregon are below the hard-water threshold, though local systems can still vary.

Oregon uses a mixed data profile across treated-water records, USGS monitoring, and estimated fallback values.

Use the city table below to compare local results. For estimated locations or unusually high readings, confirm with your utility or a home hardness test before sizing treatment equipment.

ZIP Hardness Distribution

Soft80% (320)

Slightly Hard14% (54)

Moderately Hard5% (19)

Hard1% (2)

Very Hard1% (5)

Treatment Takeaway

Hardness treatment is less likely to be needed statewide, but local water systems can still differ from the state pattern. Test first if you see scale or spotting.

How to Use This Data

Use the source coverage above to decide how much local confirmation you need for a specific city or ZIP code.

Useful Oregon City Pages

Shortcuts to city pages backed by more ZIP-code or water-system data.

Cities With More Local Data

Prioritize cities with multiple ZIPs and systems, then use source badges on each city page to separate verified treated-water records from estimates.

Top 10 Hardest Water Cities

#	City	Hardness
1	Harbor	Very Hard (307 PPM)
2	Agness	Very Hard (284 PPM)
3	Pistol River	Very Hard (284 PPM)
4	Sixes	Very Hard (284 PPM)
5	Arlington	Very Hard (275 PPM)
6	Langlois	Hard (243 PPM)
7	Canyon City	Hard (218 PPM)
8	Bates	Moderately Hard (176 PPM)
9	Kimberly	Moderately Hard (176 PPM)
10	Port Orford	Moderately Hard (163 PPM)

Top 10 Softest Water Cities

#	City	Hardness
1	Aloha	Soft (12 PPM)
2	Beavercreek	Soft (12 PPM)
3	Beaverton	Soft (12 PPM)
4	Brightwood	Soft (12 PPM)
5	Buxton	Soft (12 PPM)
6	Colton	Soft (12 PPM)
7	Corbett	Soft (12 PPM)
8	Cornelius	Soft (12 PPM)
9	Eagle Creek	Soft (12 PPM)
10	Gales Creek	Soft (12 PPM)

All Cities in Oregon

City pages marked Estimated use fallback values and should be confirmed with local testing or utility data.

AdamsModerately Hard AdelSlightly Hard AdrianSlightly Hard AgnessVery Hard AlbanySoft AlohaSoft AlseaSoft AmitySoft AntelopeSlightly Hard ApplegateSoft Arch CapeSoft ArlingtonVery Hard AshlandSoft AshwoodSoft AstoriaSlightly Hard AthenaModerately Hard AuroraSoft AzaleaSoft BandonSlightly Hard BanksSoft BatesModerately Hard Bay CitySoft BeattySoft BeaverSoft BeavercreekSoft BeavertonSoft BendSoft BlachlySoft Black Butte RancSoft BlodgettSoft BlySoft BoardmanModerately Hard BonanzaSoft BonnevilleSlightly Hard BoringSoft BridgeportSoft BrightwoodSoft BroadbentSlightly Hard BroganSlightly Hard BrooksSoft BrothersSoft BrownsvilleSoft BurnsSoft Butte FallsSoft BuxtonSoft Camas ValleySoft Camp ShermanSoft CanbySoft Cannon BeachSoft Canyon CityHard CanyonvilleSoft CarltonSoft CascadiaSoft Cave JunctionSoft Cedar HillsSoft Central PointSoft CharlestonSlightly Hard CheshireSoft ChiloquinSoft Christmas ValleySlightly Hard ClackamasSoft CloverdaleSoft CoburgSoft ColtonSoft Columbia CitySoft CondonSlightly Hard CoquilleSlightly Hard CorbettSoft CorneliusSoft CorvallisSoft Cottage GroveSoft CoveSoft CraneSlightly Hard Crater LakeSoft CrescentSoft CreswellSoft Crooked River RaSoft CulverSoft DairySoft DaleModerately Hard DallasSoft Days CreekSoft DaytonSlightly Hard DayvilleSoft Deer IslandSoft Depoe BaySoft DetroitSoft DexterSoft DiamondSoft Diamond LakeSoft DonaldSoft DorenaSoft DrainSoft DrewseySlightly Hard DundeeSlightly Hard DurkeeSoft Eagle CreekSoft Eagle PointSoft EchoModerately Hard EddyvilleSoft ElginSoft ElktonSoft ElmiraSoft EnterpriseSlightly Hard EstacadaSoft EugeneSoft FairviewSoft Fall CreekSoft Falls CitySoft FieldsSoft FlorenceSoft Fort KlamathSoft Fort RockSoft FosterSoft FrenchglenSoft FriendSlightly Hard Gales CreekSoft Garden HomeSoft GardinerSoft GaribaldiSoft GastonSoft GatesSoft GearhartSoft GervaisSoft GilchristSoft GladstoneSoft GlendaleSoft GlenwoodSoft GlideSoft Gold HillSoft Grand RondeSoft Grants PassSoft Grass ValleySlightly Hard GreenleafSoft GreshamSoft HainesSoft HalfwaySoft HalseySoft HammondSoft HarborVery Hard HarperSlightly Hard HarrisburgSoft HeboSoft HelixModerately Hard HeppnerSlightly Hard HerefordSoft HermistonModerately Hard HillsboroSoft HinesModerately Hard Hood RiverSlightly Hard HubbardSoft HuntingtonSoft IdanhaSoft Idleyld ParkSoft ImblerSoft ImnahaSoft IndependenceSoft IoneModerately Hard IronsideSlightly Hard IrrigonSlightly Hard JamiesonSlightly Hard JeffersonSoft John DaySlightly Hard JosephSoft Junction CitySoft JunturaSlightly Hard KeizerSoft KenoSoft KentSoft KerbySoft KimberlyModerately Hard KinzuaSlightly Hard Klamath FallsSoft La GrandeSoft La PineSoft LafayetteSlightly Hard Lake OswegoSoft LakesideSlightly Hard LakeviewSlightly Hard LangloisHard LeaburgSoft LebanonSoft LexingtonModerately Hard Lincoln CitySoft LogsdenSoft Long CreekSlightly Hard LoraneSoft LostineSlightly Hard LowellSoft LyonsSoft MadrasSoft MalinSoft ManningSoft ManzanitaSoft MapletonSoft MarcolaSoft MaupinSlightly Hard Mc Kenzie BridgeSoft McminnvilleSoft McnarySlightly Hard MeachamModerately Hard MedfordSoft Medical SpringsSoft MerlinSoft MerrillSoft MidlandSoft Mill CitySoft Milton FreewaterModerately Hard MilwaukieSoft MitchellSlightly Hard MolallaSoft MonmouthSoft MonroeSoft MonumentSoft MoroSlightly Hard MosierSlightly Hard Mount AngelSoft Mount Hood ParkdSlightly Hard Mount VernonSlightly Hard MulinoSoft Myrtle CreekSoft Myrtle PointSlightly Hard NehalemSoft NeotsuSoft NeskowinSoft NewbergSlightly Hard NewportSoft North BendSlightly Hard North PlainsSoft North PowderSoft NotiSoft O BrienSoft Oak GroveSoft OaklandSoft OakridgeSoft OceansideSoft OntarioSlightly Hard Oregon CitySoft OretechSoft OtisSoft OxbowSoft Pacific CitySoft PaisleySlightly Hard PaulinaSoft PendletonModerately Hard PhilomathSoft PhoenixSoft Pilot RockModerately Hard Pistol RiverVery Hard Pleasant HillSoft PlushSoft Port OrfordModerately Hard PortlandSoft PostSoft Powell ButteSoft PowersSlightly Hard Prairie CitySoft PrincetonSoft PrinevilleSoft ProspectSoft RainierSoft RedmondSoft RichlandSoft RickreallSoft RiddleSoft RileySoft RockawaySoft Rockwood CornersSoft Rogue RiverSoft RoseburgSoft RufusSlightly Hard Saint HelensSoft Saint PaulSoft SalemSoft SandySoft ScappooseSoft ScioSoft Scotts MillsSoft ScottsburgSoft Seal RockSoft SelmaSoft SenecaSoft Shady CoveSoft SheddSoft SheridanSoft SherwoodSoft SiletzSoft Silver LakeSoft SilvertonSoft SixesVery Hard South BeachSoft Sprague RiverSoft SpraySlightly Hard SpringfieldSoft StanfieldModerately Hard StaytonSoft SublimitySoft Summer LakeSoft SummervilleSoft SumpterSoft Sunny ValleySoft SunriverSoft SutherlinSoft Sweet HomeSoft SwisshomeSoft TalentSoft TangentSoft TenmileSoft The DallesSlightly Hard TidewaterSoft TigardSoft TillamookSoft TillerSoft TimberSoft Timberline LodgeSoft ToledoSoft Tolovana ParkSoft TrailSoft TroutdaleSoft TualatinSoft TurnerSoft UmpquaSoft UnionSoft UnitySoft ValeSlightly Hard VenetaSoft VernoniaSoft VidaSoft WaldportSoft WallowaSlightly Hard WaltonSoft WamicSlightly Hard Warm SpringsSoft WarrenSoft WarrentonSoft WascoSlightly Hard WelchesSoft West LinnSoft West MainSoft West StaytonSoft WestfallSlightly Hard WestfirSoft WestlakeSoft WestonModerately Hard WestportSoft WheelerSoft White CitySoft WildervilleSoft WillaminaSoft WilliamsSoft WilsonvilleSoft Winchester BaySoft WinstonSoft WoodburnSoft YachatsSoft YamhillSoft YoncallaSoft ZigzagSoft