Roslyn Heights, NY water hardness

Tap water hardness
55mg/L
3.2gpg
Soft

Reported by WA of Western Nassau · October 2025

NY typical
31 mg/L
EPA health violations since 2016
0
Data
Utility report

Roslyn Heights water measures 55 mg/L (3.2 gpg) of hardness, soft by USGS standards. The number comes from WA of Western Nassau, dated October 2025.

Roslyn Heights on the hardness scale, with nearby cities
060120180240300360+NY typical 31Mineola: 51 mg/LMineola 51Carle Place: 51 mg/LCarle Place 51Garden City Park: 51 mg/LGarden City Park 51Old Westbury: 54 mg/LOld Westbury 54Williston Park: 55 mg/LWilliston Park 55Westbury: 55 mg/LWestbury 55North New Hyde Park: 55 mg/LNorth New Hyde Park 55East Hills: 56 mg/LEast Hills 56North Hills: 66 mg/LNorth Hills 66Manhasset: 66 mg/LManhasset 66Roslyn Heights 55mg/L as calcium carbonate060120180240300360+NY 31Mineola: 51 mg/LMineola 51Carle Place: 51 mg/LCarle Place 51Old Westbury: 54 mg/LOld Westbu. 54Williston Park: 55 mg/LWilliston. 55East Hills: 56 mg/LEast Hills 56North Hills: 66 mg/LNorth Hills 6655 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 55 mg/L, Roslyn Heights is 24 mg/L above the typical New York figure of 31. Of the 10 nearest cities we track, 4 have softer water and 3 have harder. The range nearby runs from 51 mg/L in Mineola to 66 in North Hills.

What 55 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 55 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 Roslyn Heights's water system

WA of Western Nassau · PWSID NY2902830

No health-based violations since 2016

Serves about 120,000 people from groundwater.

Health-based
0
Monitoring or reporting
1
Open now
0

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

No. It measures about 55 mg/L (3.2 grains per gallon), which the USGS classes as soft.

What is the water hardness in Roslyn Heights in grains per gallon?

About 3.2 gpg. One grain per gallon equals 17.1 mg/L, so 55 mg/L divided by 17.1 gives 3.2.

Has the Roslyn Heights water system had EPA violations?

EPA records show no health-based violations for WA of Western Nassau since 2016. There were also 1 monitoring or reporting violation, which are about late or missing tests and notices.

Nearby cities

All 149 cities in New York

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