How hard is the water in Westlake Village, CA?

Tap water hardness
88mg/L
5.2gpg
Moderately hardReports range 88–112

Reported by Las Virgenes MWD · October 2025

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

Westlake Village water measures 88 mg/L (5.2 gpg) of hardness, moderately hard by USGS standards. The number comes from Las Virgenes MWD, dated October 2025. Reports for this system disagree, with values from 88 to 112 mg/L.

Westlake Village on the hardness scale, with nearby cities
060120180240300360+CA typical 121Santa Monica: 57 mg/LSanta Monica 57Calabasas: 77 mg/LCalabasas 77Topanga: 77 mg/LTopanga 77Fillmore: 77 mg/LFillmore 77Agoura Hills: 88 mg/LAgoura Hills 88Thousand Oaks: 117 mg/LThousand Oaks 117Oak Park: 138 mg/LOak Park 138Simi Valley: 181 mg/LSimi Valley 181Moorpark: 190 mg/LMoorpark 190Camarillo: 218 mg/LCamarillo 218Westlake Village 88mg/L as calcium carbonate060120180240300360+CA 121Calabasas: 77 mg/LCalabasas 77Agoura Hills: 88 mg/LAgoura Hil. 88Thousand Oaks: 117 mg/LThousand O. 117Oak Park: 138 mg/LOak Park 138Simi Valley: 181 mg/LSimi Valley 181Moorpark: 190 mg/LMoorpark 19088 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 88 mg/L, Westlake Village is 33 mg/L below the typical California figure of 121. Of the 10 nearest cities we track, 4 have softer water and 5 have harder. The range nearby runs from 57 mg/L in Santa Monica to 218 in Camarillo.

What 88 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 Westlake Village

3 people × 75 gallons a day × 5.2 gpg = 1,166 grains a day. A 24,000-grain unit regenerates about every 20 days.

Size it for your household

EPA record for Westlake Village's water system

Las Virgenes MWD · PWSID CA1910225

No health-based violations since 2016

Serves about 77,562 people from surface water.

Health-based
0
Monitoring or reporting
0
Open now
0

TapWaterData ties Westlake Village to this system. EPA's service-area records do not name Westlake Village, 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 Westlake Village water hard?

Somewhat. It measures about 88 mg/L (5.2 grains per gallon), which the USGS classes as moderately hard.

What is the water hardness in Westlake Village in grains per gallon?

About 5.2 gpg. One grain per gallon equals 17.1 mg/L, so 88 mg/L divided by 17.1 gives 5.2.

What size water softener do I need in Westlake Village?

For 3 people using 75 gallons each per day, 5.2 gpg works out to about 1,166 grains a day. A 24,000-grain softener covers that with a regeneration about every 20 days.

Has the Westlake Village water system had EPA violations?

EPA records show no health-based violations for Las Virgenes MWD since 2016.

Nearby cities

All 515 cities in California

Hardness data: TapWaterData US Water Hardness (utility report, October 6, 2025), CC BY 4.0. Population: US Census Bureau. Violations: EPA ECHO. How we use them.