How hard is the water in Davis, CA?

Tap water hardness
68mg/L
4.0gpg
Moderately hard

Reported by City of Davis · October 2025

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

Davis water measures 68 mg/L (4.0 gpg) of hardness, moderately hard by USGS standards. The number comes from City of Davis, dated October 2025.

Davis on the hardness scale, with nearby cities
060120180240300360+CA typical 121Fruitridge Pocket: 25 mg/LFruitridge Pocket 25Lemon Hill: 25 mg/LLemon Hill 25West Sacramento: 35 mg/LWest Sacramento 35Woodland: 44 mg/LWoodland 44Sacramento: 45 mg/LSacramento 45Parkway: 66 mg/LParkway 66Rio Linda: 93 mg/LRio Linda 93Vacaville: 94 mg/LVacaville 94Dixon: 152 mg/LDixon 152University of California-Davis: 212 mg/LUniversity of California-Davis 212Davis 68mg/L as calcium carbonate060120180240300360+CA 121Fruitridge Pocket: 25 mg/LFruitridge. 25West Sacramento: 35 mg/LWest Sacra. 35Woodland: 44 mg/LWoodland 44Sacramento: 45 mg/LSacramento 45Dixon: 152 mg/LDixon 152University of California-Davis: 212 mg/LUniversity. 21268 mg/Lmg/L as calcium carbonate
Soft 0–60 mg/LModerately hard 61–120 mg/LHard 121–180 mg/LVery hard 181+ mg/L

Davis sits 53 mg/L below the typical California figure of 121. Of the 10 nearest cities we track, 6 have softer water and 4 have harder. The range nearby runs from 25 mg/L in Fruitridge Pocket to 212 in University of California-Davis.

What 68 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 Davis

3 people × 75 gallons a day × 4.0 gpg = 898 grains a day. A 24,000-grain unit regenerates about every 26 days.

Size it for your household

EPA record for Davis's water system

City of Davis · PWSID CA5710001

No health-based violations since 2016

Serves about 67,826 people from surface water.

Health-based
0
Monitoring or reporting
0
Open now
0

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 Davis water hard?

Somewhat. It measures about 68 mg/L (4.0 grains per gallon), which the USGS classes as moderately hard.

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

About 4.0 gpg. One grain per gallon equals 17.1 mg/L, so 68 mg/L divided by 17.1 gives 4.0.

What size water softener do I need in Davis?

For 3 people using 75 gallons each per day, 4.0 gpg works out to about 898 grains a day. A 24,000-grain softener covers that with a regeneration about every 26 days.

Has the Davis water system had EPA violations?

EPA records show no health-based violations for City of Davis since 2016.

Nearby cities

All 515 cities in California

Hardness data: TapWaterData US Water Hardness (utility report, October 1, 2025), CC BY 4.0. Population: US Census Bureau. Violations: EPA ECHO. How we use them.