Hard water in Selah, WA

Tap water hardness
147mg/L
8.6gpg
Hard

Calculated from the utility's calcium and magnesium results · August 2022

WA typical
36 mg/L
EPA health violations since 2016
1
Softener for 3 people
24k grain
Data
Calculated from utility data

Tap water in Selah has about 147 mg/L of hardness, which is 8.6 grains per gallon. On the USGS scale that counts as hard. TapWaterData worked it out from the calcium and magnesium levels the local utility reports (August 2022).

Selah on the hardness scale, with nearby cities
060120180240300360+WA typical 36Union Gap: 31 mg/LUnion Gap 31West Richland: 33 mg/LWest Richland 33Yakima: 39 mg/LYakima 39Ellensburg: 60 mg/LEllensburg 60Toppenish: 63 mg/LToppenish 63East Wenatchee: 80 mg/LEast Wenatchee 80Wenatchee: 80 mg/LWenatchee 80Terrace Heights: 88 mg/LTerrace Heights 88Richland: 89 mg/LRichland 89Grandview: 208 mg/LGrandview 208Selah 147mg/L as calcium carbonate060120180240300360+WA 36Union Gap: 31 mg/LUnion Gap 31Yakima: 39 mg/LYakima 39Ellensburg: 60 mg/LEllensburg 60Toppenish: 63 mg/LToppenish 63Terrace Heights: 88 mg/LTerrace He. 88Grandview: 208 mg/LGrandview 208147 mg/Lmg/L as calcium carbonate
Soft 0–60 mg/LModerately hard 61–120 mg/LHard 121–180 mg/LVery hard 181+ mg/L

At 147 mg/L, Selah is 111 mg/L above the typical Washington figure of 36. Of the 10 nearest cities we track, 9 have softer water and 1 has harder. The range nearby runs from 31 mg/L in Union Gap to 208 in Grandview.

What 147 mg/L means at home

Expect white crust on faucets and showerheads, plus spots on dishes that come out of the dishwasher.

Kettles collect scale quickly. Water heaters build up sediment at the bottom of the tank, which makes them work harder over time.

Soap and detergent need a little more to lather, and soap scum shows up in the tub.

Hardness is not a health problem, and EPA sets no limit for it. It is a matter of scale and soap.

What to do about it

At 147 mg/L most of the trouble is scale, and only a few things deal with it.

Ion-exchange water softener

The standard whole-house fix. It swaps calcium and magnesium for sodium or potassium and needs salt plus a drain. Size it with the calculator below.

Salt-free conditioner

No salt and no drain line. It changes how minerals form scale instead of removing them, so water still tests hard.

Reverse osmosis or carbon filter

Under-sink reverse osmosis removes minerals from drinking water only. Plain carbon filters improve taste but do not soften.

Softener size for Selah

3 people × 75 gallons a day × 8.6 gpg = 1,931 grains a day. A 24,000-grain unit regenerates about every 12 days.

Size it for your household

EPA record for Selah's water system

Selah City of · PWSID WA5377400

1 health-based violation since 2016

Serves about 9,331 people from groundwater.

Health-based
1
Monitoring or reporting
4
Open now
0

EPA lists this system as serving Selah.

20162017201820192020202120222023202420252026Total Coliform Rule'16'18'20'22'24'26Total Coliform Rule
Each dot is one health-based violation, placed at the start of its compliance period.
Contaminant or ruleViolationsPeriodStatus
Total Coliform Rulebacteria12021Resolved

Health-based means a contaminant above its legal limit or a missed treatment step. Monitoring and reporting violations are late or missing tests and notices. Source: EPA ECHO, 2026Q3 export, violations with periods starting 2016 or later. Full EPA record.

Questions

Is Selah water hard?

Yes. It measures about 147 mg/L (8.6 grains per gallon), which the USGS classes as hard.

What is the water hardness in Selah in grains per gallon?

About 8.6 gpg. One grain per gallon equals 17.1 mg/L, so 147 mg/L divided by 17.1 gives 8.6.

What size water softener do I need in Selah?

For 3 people using 75 gallons each per day, 8.6 gpg works out to about 1,931 grains a day. A 24,000-grain softener covers that with a regeneration about every 12 days.

Has the Selah water system had EPA violations?

EPA records show 1 health-based violation for Selah City of since 2016, involving Total Coliform Rule. There were also 4 monitoring or reporting violations, which are about late or missing tests and notices.

Nearby cities

All 145 cities in Washington

Hardness data: TapWaterData US Water Hardness (calculated from utility data, August 11, 2022), CC BY 4.0. Population: US Census Bureau. Violations: EPA ECHO. How we use them.