How hard is the water in Oakmont, PA?

Tap water hardness
90mg/L
5.3gpg
Moderately hard

Reported by Oakmont Water Authority · August 2025

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

The water in Oakmont carries roughly 90 mg/L of dissolved calcium and magnesium, or 5.3 grains per gallon. That is moderately hard water. The number comes from Oakmont Water Authority, dated August 2025.

Oakmont on the hardness scale, with nearby cities
060120180240300360+PA typical 127Plum: 66 mg/LPlum 66Glenshaw: 88 mg/LGlenshaw 88Allison Park: 88 mg/LAllison Park 88Wilkinsburg: 90 mg/LWilkinsburg 90Forest Hills: 90 mg/LForest Hills 90Swissvale: 90 mg/LSwissvale 90Monroeville: 96 mg/LMonroeville 96Pittsburgh: 100 mg/LPittsburgh 100Fox Chapel: 102 mg/LFox Chapel 102Munhall: 102 mg/LMunhall 102Oakmont 90mg/L as calcium carbonate060120180240300360+PA 127Plum: 66 mg/LPlum 66Glenshaw: 88 mg/LGlenshaw 88Wilkinsburg: 90 mg/LWilkinsburg 90Forest Hills: 90 mg/LForest Hil. 90Swissvale: 90 mg/LSwissvale 90Fox Chapel: 102 mg/LFox Chapel 10290 mg/Lmg/L as calcium carbonate
Soft 0–60 mg/LModerately hard 61–120 mg/LHard 121–180 mg/LVery hard 181+ mg/L

Oakmont sits 37 mg/L below the typical Pennsylvania figure of 127. Of the 10 nearest cities we track, 3 have softer water and 4 have harder. The range nearby runs from 66 mg/L in Plum to 102 in Fox Chapel.

What 90 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 Oakmont

3 people × 75 gallons a day × 5.3 gpg = 1,184 grains a day. A 24,000-grain unit regenerates about every 20 days.

Size it for your household

EPA record for Oakmont's water system

Oakmont Water Authority · PWSID PA5020036

No health-based violations since 2016

Serves about 39,901 people from surface water.

Health-based
0
Monitoring or reporting
6
Open now
0

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 Oakmont water hard?

Somewhat. It measures about 90 mg/L (5.3 grains per gallon), which the USGS classes as moderately hard.

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

About 5.3 gpg. One grain per gallon equals 17.1 mg/L, so 90 mg/L divided by 17.1 gives 5.3.

What size water softener do I need in Oakmont?

For 3 people using 75 gallons each per day, 5.3 gpg works out to about 1,184 grains a day. A 24,000-grain softener covers that with a regeneration about every 20 days.

Has the Oakmont water system had EPA violations?

EPA records show no health-based violations for Oakmont Water Authority since 2016. There were also 6 monitoring or reporting violations, which are about late or missing tests and notices.

Nearby cities

All 172 cities in Pennsylvania

Hardness data: TapWaterData US Water Hardness (utility report, August 15, 2025), CC BY 4.0. Population: US Census Bureau. Violations: EPA ECHO. How we use them.