Martha Lake, WA water hardness

Tap water hardness
13mg/L
0.7gpg
Soft

Reported by Alderwood Water District · September 2025

WA typical
36 mg/L
EPA health violations since 2016
0
Data
Utility report

Tap water in Martha Lake has about 13 mg/L of hardness, which is 0.7 grains per gallon. On the USGS scale that counts as soft. The number comes from Alderwood Water District, dated September 2025.

Martha Lake on the hardness scale, with nearby cities
060120180240300360+WA typical 36Mill Creek: 13 mg/LMill Creek 13North Lynnwood: 13 mg/LNorth Lynnwood 13Mill Creek East: 13 mg/LMill Creek East 13Lake Stickney: 13 mg/LLake Stickney 13Alderwood Manor: 13 mg/LAlderwood Manor 13Bothell West: 13 mg/LBothell West 13Bothell East: 13 mg/LBothell East 13Brier: 13 mg/LBrier 13Lynnwood: 15 mg/LLynnwood 15Silver Firs: 43 mg/LSilver Firs 43Martha Lake 13mg/L as calcium carbonate060120180240300360+WA 36Mill Creek: 13 mg/LMill Creek 13North Lynnwood: 13 mg/LNorth Lynn. 13Mill Creek East: 13 mg/LMill Creek. 13Lake Stickney: 13 mg/LLake Stick. 13Alderwood Manor: 13 mg/LAlderwood. 13Bothell West: 13 mg/LBothell We. 1313 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 13 mg/L, Martha Lake is 23 mg/L below the typical Washington figure of 36. None of the 10 nearest cities we track has softer water. The range nearby runs from 13 mg/L in Mill Creek to 43 in Silver Firs.

What 13 mg/L means at home

Soap and shampoo lather with very little product. Kettles and showerheads stay mostly free of white crust.

Some people notice that soap feels slow to rinse off in soft water. That slippery feel is normal and harmless.

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

Nothing, as far as hardness goes. At 13 mg/L a softener would have almost nothing to remove.

Carbon filter

If the water tastes of chlorine, a pitcher or faucet carbon filter takes care of that. It does not change hardness.

EPA record for Martha Lake's water system

Alderwood Water District · PWSID WA5301300

No health-based violations since 2016

Serves about 245,715 people from surface water.

Health-based
0
Monitoring or reporting
0
Open now
0

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

No. It measures about 13 mg/L (0.7 grains per gallon), which the USGS classes as soft.

What is the water hardness in Martha Lake in grains per gallon?

About 0.7 gpg. One grain per gallon equals 17.1 mg/L, so 13 mg/L divided by 17.1 gives 0.7.

Has the Martha Lake water system had EPA violations?

EPA records show no health-based violations for Alderwood Water District since 2016.

Nearby cities

All 145 cities in Washington

Hardness data: TapWaterData US Water Hardness (utility report, September 3, 2025), CC BY 4.0. Population: US Census Bureau. Violations: EPA ECHO. How we use them.