Uniondale, NY water hardness

Tap water hardness
51mg/L
3.0gpg
Soft

Reported by WA of Western Nassau · October 2025

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

The water in Uniondale carries roughly 51 mg/L of dissolved calcium and magnesium, or 3.0 grains per gallon. That is soft water. The number comes from WA of Western Nassau, dated October 2025.

Uniondale on the hardness scale, with nearby cities
060120180240300360+NY typical 31Roosevelt: 33 mg/LRoosevelt 33East Meadow: 42 mg/LEast Meadow 42North Merrick: 42 mg/LNorth Merrick 42New Cassel: 45 mg/LNew Cassel 45West Hempstead: 48 mg/LWest Hempstead 48Carle Place: 51 mg/LCarle Place 51Garden City: 51 mg/LGarden City 51Mineola: 51 mg/LMineola 51Hempstead: 53 mg/LHempstead 53Westbury: 55 mg/LWestbury 55Uniondale 51mg/L as calcium carbonate060120180240300360+NY 31Roosevelt: 33 mg/LRoosevelt 33East Meadow: 42 mg/LEast Meadow 42North Merrick: 42 mg/LNorth Merr. 42Carle Place: 51 mg/LCarle Place 51Garden City: 51 mg/LGarden City 51Hempstead: 53 mg/LHempstead 5351 mg/Lmg/L as calcium carbonate
Soft 0–60 mg/LModerately hard 61–120 mg/LHard 121–180 mg/LVery hard 181+ mg/L

Uniondale sits 20 mg/L above the typical New York figure of 31. Of the 10 nearest cities we track, 5 have softer water and 2 have harder. The range nearby runs from 33 mg/L in Roosevelt to 55 in Westbury.

What 51 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 51 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 Uniondale'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 Uniondale to this system. EPA's service-area records do not name Uniondale, 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 Uniondale water hard?

No. It measures about 51 mg/L (3.0 grains per gallon), which the USGS classes as soft.

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

About 3.0 gpg. One grain per gallon equals 17.1 mg/L, so 51 mg/L divided by 17.1 gives 3.0.

Has the Uniondale 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.