How hard is the water in Boyes Hot Springs, CA?

Tap water hardness
62mg/L
3.6gpg
Moderately hard

Reported by Valley of the Moon Water District · September 2023

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

Boyes Hot Springs water measures 62 mg/L (3.6 gpg) of hardness, moderately hard by USGS standards. The number comes from Valley of the Moon Water District, dated September 2023.

Boyes Hot Springs on the hardness scale, with nearby cities
060120180240300360+CA typical 121Napa: 54 mg/LNapa 54Novato: 63 mg/LNovato 63American Canyon: 65 mg/LAmerican Canyon 65Vallejo: 82 mg/LVallejo 82Sonoma: 84 mg/LSonoma 84Petaluma: 105 mg/LPetaluma 105Rohnert Park: 106 mg/LRohnert Park 106Cotati: 106 mg/LCotati 106Santa Rosa: 121 mg/LSanta Rosa 121Sebastopol: 142 mg/LSebastopol 142Boyes Hot Springs 62mg/L as calcium carbonate060120180240300360+CA 121Napa: 54 mg/LNapa 54Sonoma: 84 mg/LSonoma 84Petaluma: 105 mg/LPetaluma 105Rohnert Park: 106 mg/LRohnert Pa. 106Cotati: 106 mg/LCotati 106Santa Rosa: 121 mg/LSanta Rosa 12162 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 62 mg/L, Boyes Hot Springs is 59 mg/L below the typical California figure of 121. Of the 10 nearest cities we track, 1 has softer water and 9 have harder. The range nearby runs from 54 mg/L in Napa to 142 in Sebastopol.

What 62 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 Boyes Hot Springs

3 people × 75 gallons a day × 3.6 gpg = 810 grains a day. A 24,000-grain unit regenerates about every 29 days.

Size it for your household

EPA record for Boyes Hot Springs's water system

Valley of the Moon Water District · PWSID CA4910013

No health-based violations since 2016

Serves about 23,140 people from groundwater.

Health-based
0
Monitoring or reporting
2
Open now
0

TapWaterData ties Boyes Hot Springs to this system. EPA's service-area records do not name Boyes Hot Springs, so check the utility printed on your water bill.

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 Boyes Hot Springs water hard?

Somewhat. It measures about 62 mg/L (3.6 grains per gallon), which the USGS classes as moderately hard.

What is the water hardness in Boyes Hot Springs in grains per gallon?

About 3.6 gpg. One grain per gallon equals 17.1 mg/L, so 62 mg/L divided by 17.1 gives 3.6.

What size water softener do I need in Boyes Hot Springs?

For 3 people using 75 gallons each per day, 3.6 gpg works out to about 810 grains a day. A 24,000-grain softener covers that with a regeneration about every 29 days.

Has the Boyes Hot Springs water system had EPA violations?

EPA records show no health-based violations for Valley of the Moon Water District since 2016. There were also 2 monitoring or reporting violations, which are about late or missing tests and notices.

Nearby cities

All 515 cities in California

Hardness data: TapWaterData US Water Hardness (utility report, September 26, 2023), CC BY 4.0. Population: US Census Bureau. Violations: EPA ECHO. How we use them.