How hard is the water in Pullman, WA?

Tap water hardness
115mg/L
6.7gpg
Moderately hard

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

WA typical
36 mg/L
EPA health violations since 2016
0
Softener for 3 people
24k grain
Data
Calculated from utility data

Pullman water measures 115 mg/L (6.7 gpg) of hardness, moderately hard by USGS standards. TapWaterData worked it out from the calcium and magnesium levels the local utility reports (August 2022).

Pullman on the hardness scale, with nearby cities
060120180240300360+WA typical 36Othello: 33 mg/LOthello 33Walla Walla: 39 mg/LWalla Walla 39Cheney: 55 mg/LCheney 55Finley: 96 mg/LFinley 96Country Homes: 124 mg/LCountry Homes 124Mead: 124 mg/LMead 124Town and Country: 130 mg/LTown and Country 130Spokane Valley: 131 mg/LSpokane Valley 131Spokane: 131 mg/LSpokane 131Airway Heights: 131 mg/LAirway Heights 131Pullman 115mg/L as calcium carbonate060120180240300360+WA 36Cheney: 55 mg/LCheney 55Country Homes: 124 mg/LCountry Ho. 124Town and Country: 130 mg/LTown and C. 130Spokane Valley: 131 mg/LSpokane Va. 131Spokane: 131 mg/LSpokane 131Airway Heights: 131 mg/LAirway Hei. 131115 mg/Lmg/L as calcium carbonate
Soft 0–60 mg/LModerately hard 61–120 mg/LHard 121–180 mg/LVery hard 181+ mg/L

Pullman sits 79 mg/L above the typical Washington figure of 36. Of the 10 nearest cities we track, 4 have softer water and 6 have harder. The range nearby runs from 33 mg/L in Othello to 131 in Spokane Valley.

What 115 mg/L means at home

You may see faint white spots on glasses and shower doors after the water dries.

Scale builds up slowly. A kettle or coffee maker needs descaling now and then, maybe every few months.

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

Optional. Plenty of households at this level live with it and descale the kettle now and then.

Water softener

Worth a look if spots on glass bother you, or if your tankless water heater manual asks for softer water.

Carbon filter

Improves taste and removes chlorine. It leaves calcium and magnesium in place.

Softener size for Pullman

3 people × 75 gallons a day × 6.7 gpg = 1,514 grains a day. A 24,000-grain unit regenerates about every 15 days.

Size it for your household

EPA record for Pullman's water system

Pullman Water Department City of · PWSID WA5369880

No health-based violations since 2016

Serves about 31,315 people from groundwater.

Health-based
0
Monitoring or reporting
8
Open now
0

EPA lists this system as serving Pullman.

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 Pullman water hard?

Somewhat. It measures about 115 mg/L (6.7 grains per gallon), which the USGS classes as moderately hard.

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

About 6.7 gpg. One grain per gallon equals 17.1 mg/L, so 115 mg/L divided by 17.1 gives 6.7.

What size water softener do I need in Pullman?

For 3 people using 75 gallons each per day, 6.7 gpg works out to about 1,514 grains a day. A 24,000-grain softener covers that with a regeneration about every 15 days.

Has the Pullman water system had EPA violations?

EPA records show no health-based violations for Pullman Water Department City of since 2016. There were also 8 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 25, 2022), CC BY 4.0. Population: US Census Bureau. Violations: EPA ECHO. How we use them.