How hard is the water in Cochituate, MA?

Tap water hardness
93mg/L
5.5gpg
Moderately hardReports range 93–113

Reported by Natick Water Department · October 2025

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

Cochituate water measures 93 mg/L (5.5 gpg) of hardness, moderately hard by USGS standards. The number comes from Natick Water Department, dated October 2025. Reports for this system disagree, with values from 93 to 113 mg/L.

Cochituate on the hardness scale, with nearby cities
060120180240300360+MA typical 38Watertown: 16 mg/LWatertown 16Belmont: 16 mg/LBelmont 16Waltham: 17 mg/LWaltham 17Newton: 32 mg/LNewton 32Framingham: 52 mg/LFramingham 52West Concord: 57 mg/LWest Concord 57Marlborough: 67 mg/LMarlborough 67Maynard: 86 mg/LMaynard 86Wellesley: 89 mg/LWellesley 89Needham: 96 mg/LNeedham 96Cochituate 93mg/L as calcium carbonate060120180240300360+MA 38Waltham: 17 mg/LWaltham 17Newton: 32 mg/LNewton 32Framingham: 52 mg/LFramingham 52Maynard: 86 mg/LMaynard 86Wellesley: 89 mg/LWellesley 89Needham: 96 mg/LNeedham 9693 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 93 mg/L, Cochituate is 55 mg/L above the typical Massachusetts figure of 38. Of the 10 nearest cities we track, 9 have softer water and 1 has harder. The range nearby runs from 16 mg/L in Watertown to 96 in Needham.

What 93 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 Cochituate

3 people × 75 gallons a day × 5.5 gpg = 1,228 grains a day. A 24,000-grain unit regenerates about every 19 days.

Size it for your household

EPA record for Cochituate's water system

Natick Water and Sewer Division · PWSID MA3198000

No health-based violations since 2016

Serves about 37,006 people from groundwater.

Health-based
0
Monitoring or reporting
0
Open now
0

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

Somewhat. It measures about 93 mg/L (5.5 grains per gallon), which the USGS classes as moderately hard.

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

About 5.5 gpg. One grain per gallon equals 17.1 mg/L, so 93 mg/L divided by 17.1 gives 5.5.

What size water softener do I need in Cochituate?

For 3 people using 75 gallons each per day, 5.5 gpg works out to about 1,228 grains a day. A 24,000-grain softener covers that with a regeneration about every 19 days.

Has the Cochituate water system had EPA violations?

EPA records show no health-based violations for Natick Water and Sewer Division since 2016.

Nearby cities

All 104 cities in Massachusetts

Hardness data: TapWaterData US Water Hardness (utility report, October 7, 2025), CC BY 4.0. Population: US Census Bureau. Violations: EPA ECHO. How we use them.