How hard is the water in The Dalles, OR?

Tap water hardness
78mg/L
4.6gpg
Moderately hard

Reported by The Dalles, City of · December 2024

OR typical
24 mg/L
EPA health violations since 2016
0
Softener for 3 people
24k grain
Data
Utility report

The water in The Dalles carries roughly 78 mg/L of dissolved calcium and magnesium, or 4.6 grains per gallon. That is moderately hard water. The number comes from The Dalles, City of, dated December 2024.

The Dalles on the hardness scale, with nearby cities
060120180240300360+OR typical 24Portland: 20 mg/LPortland 20Gladstone: 23 mg/LGladstone 23Oregon City: 23 mg/LOregon City 23Jennings Lodge: 23 mg/LJennings Lodge 23Happy Valley: 24 mg/LHappy Valley 24Oatfield: 56 mg/LOatfield 56Troutdale: 70 mg/LTroutdale 70Fairview: 70 mg/LFairview 70Gresham: 70 mg/LGresham 70Milwaukie: 120 mg/LMilwaukie 120The Dalles 78mg/L as calcium carbonate060120180240300360+OR 24Gladstone: 23 mg/LGladstone 23Happy Valley: 24 mg/LHappy Vall. 24Oatfield: 56 mg/LOatfield 56Troutdale: 70 mg/LTroutdale 70Fairview: 70 mg/LFairview 70Gresham: 70 mg/LGresham 7078 mg/Lmg/L as calcium carbonate
Soft 0–60 mg/LModerately hard 61–120 mg/LHard 121–180 mg/LVery hard 181+ mg/L

The Dalles sits 54 mg/L above the typical Oregon figure of 24. Of the 10 nearest cities we track, 9 have softer water and 1 has harder. The range nearby runs from 20 mg/L in Portland to 120 in Milwaukie.

What 78 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 The Dalles

3 people × 75 gallons a day × 4.6 gpg = 1,033 grains a day. A 24,000-grain unit regenerates about every 23 days.

Size it for your household

EPA record for The Dalles's water system

The Dalles, City of · PWSID OR4100869

No health-based violations since 2016

Serves about 13,010 people from surface water.

Health-based
0
Monitoring or reporting
19
Open now
1

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 The Dalles water hard?

Somewhat. It measures about 78 mg/L (4.6 grains per gallon), which the USGS classes as moderately hard.

What is the water hardness in The Dalles in grains per gallon?

About 4.6 gpg. One grain per gallon equals 17.1 mg/L, so 78 mg/L divided by 17.1 gives 4.6.

What size water softener do I need in The Dalles?

For 3 people using 75 gallons each per day, 4.6 gpg works out to about 1,033 grains a day. A 24,000-grain softener covers that with a regeneration about every 23 days.

Has the The Dalles water system had EPA violations?

EPA records show no health-based violations for The Dalles, City of since 2016. There were also 19 monitoring or reporting violations, which are about late or missing tests and notices.

Nearby cities

All 53 cities in Oregon

Hardness data: TapWaterData US Water Hardness (utility report, December 1, 2024), CC BY 4.0. Population: US Census Bureau. Violations: EPA ECHO. How we use them.