Hard water in Lawndale, CA

Tap water hardness
188mg/L
11.0gpg
Very hard

Reported by GSWC - Southwest · October 2025

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

Tap water in Lawndale has about 188 mg/L of hardness, which is 11.0 grains per gallon. On the USGS scale that counts as very hard. The number comes from GSWC - Southwest, dated October 2025.

Lawndale on the hardness scale, with nearby cities
060120180240300360+CA typical 121El Segundo: 172 mg/LEl Segundo 172Alondra Park: 185 mg/LAlondra Park 185Del Aire: 185 mg/LDel Aire 185Gardena: 185 mg/LGardena 185Lennox: 185 mg/LLennox 185West Athens: 185 mg/LWest Athens 185Hawthorne: 189 mg/LHawthorne 189Hermosa Beach: 198 mg/LHermosa Beach 198Redondo Beach: 198 mg/LRedondo Beach 198Manhattan Beach: 215 mg/LManhattan Beach 215Lawndale 188mg/L as calcium carbonate060120180240300360+CA 121Alondra Park: 185 mg/LAlondra Pa. 185Del Aire: 185 mg/LDel Aire 185Gardena: 185 mg/LGardena 185Lennox: 185 mg/LLennox 185Hawthorne: 189 mg/LHawthorne 189Hermosa Beach: 198 mg/LHermosa Be. 198188 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 188 mg/L, Lawndale is 67 mg/L above 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 172 mg/L in El Segundo to 215 in Manhattan Beach.

What 188 mg/L means at home

Scale forms fast here. Kettles and coffee makers need regular descaling, and showerheads clog unless you clean them.

Tank water heaters collect mineral sediment that insulates the water from the burner, so flushing the tank matters more than usual.

Dishes and glass shower doors spot easily. Soap scum and a dull film on hair or laundry are common complaints.

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

At 188 mg/L most of the trouble is scale, and only a few things deal with it.

Ion-exchange water softener

The standard whole-house fix. It swaps calcium and magnesium for sodium or potassium and needs salt plus a drain. Size it with the calculator below.

Salt-free conditioner

No salt and no drain line. It changes how minerals form scale instead of removing them, so water still tests hard.

Reverse osmosis or carbon filter

Under-sink reverse osmosis removes minerals from drinking water only. Plain carbon filters improve taste but do not soften.

Softener size for Lawndale

3 people × 75 gallons a day × 11.0 gpg = 2,480 grains a day. A 24,000-grain unit regenerates about every 9 days.

Size it for your household

EPA record for Lawndale's water system

GSWC - Southwest · PWSID CA1910155

No health-based violations since 2016

Serves about 277,740 people from surface water.

Health-based
0
Monitoring or reporting
0
Open now
0

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

Yes. It measures about 188 mg/L (11.0 grains per gallon), which the USGS classes as very hard.

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

About 11.0 gpg. One grain per gallon equals 17.1 mg/L, so 188 mg/L divided by 17.1 gives 11.0.

What size water softener do I need in Lawndale?

For 3 people using 75 gallons each per day, 11.0 gpg works out to about 2,480 grains a day. A 24,000-grain softener covers that with a regeneration about every 9 days.

Has the Lawndale water system had EPA violations?

EPA records show no health-based violations for GSWC - Southwest since 2016.

Nearby cities

All 515 cities in California

Hardness data: TapWaterData US Water Hardness (utility report, October 2, 2025), CC BY 4.0. Population: US Census Bureau. Violations: EPA ECHO. How we use them.