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Franklin Square Water Hardness & Quality Report (2026)

Water Hardness

hard

~120–179 mg/L

Hard

estimated · not lab-verified

Source

groundwater

pH Level

8

neutral = 7.0

Lead

0.007 mg/L

✓ Below action level

TDS

332.7 mg/L

Est. Daily Cost

$0.40

energy & soap waste

Source: See methodology section below · Updated 2026

hard~120–179 mg/LHard · est.

0–60

mg/L

Soft

61–120

mg/L

Moderately Hard

121–180

mg/L

Hard

180+

mg/L

Very Hard

Appliance Damage Report

In Franklin Square, your appliances are currently losing 20% efficiency due to mineral buildup.

ApplianceIn Franklin SquareSoft Water CityEfficiency Loss
Kettle
6.8 yrs
8.5 yrs-20%
Washing Machine
9.6 yrs
12 yrs-20%
Water Heater
12 yrs
15 yrs-20%

Regional Water Comparison

How Franklin Square compares to its nearest neighbours

CityHardnessPFAS (ppt)RiskSource
Franklin Square, New York≈ 120–179 mg/L0 ppt🟠 Hardgroundwater
West Hempstead, New York≈ 120–179 mg/L0 ppt🟠 Hardgroundwater
Floral Park, New York≈ 120–179 mg/L5.9 ppt🟠 Hardreservoir
North Valley Stream, New York17 mg/L3.6 ppt🟢 Softreservoir
Elmont, New York≈ 180+ mg/L4 ppt🔴 Very Hardmixed

National Benchmark

How Franklin Square compares to the USA average

BenchmarkHardnessAppliance Risk
Franklin Square≈ 120–179 mg/L🟠 Moderate
USA National Avg151 mg/L🟠 Moderate
Scarsdale Top Rated0.02 mg/L🟢 None

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What Makes Franklin Square's Water Unique?

Local geology and source profile

Source: GroundwaterTDS: 332.7 mg/LpH: 8

Franklin Square Water District (FSWD) serves the Franklin Square area of Nassau County, New York, drawing its supply from local groundwater wells. The utility operates multiple supply wells and delivers treated water to residential and commercial customers throughout the service area. FSWD publishes annual Consumer Confidence Reports detailing water quality testing and treatment processes, and has been constructing Advanced Oxidation Process (AOP) treatment facilities to address emerging contaminants. The 2022 Water Quality Report identified 1,4-dioxane at 1.1 ppb, slightly above New York State's maximum contaminant level, with remediation underway.

The Franklin Square water supply originates from groundwater aquifers underlying Long Island, composed of Quaternary glacial deposits overlying Cretaceous-age sand and clay formations. These geological layers contain dissolved minerals — primarily calcium and magnesium carbonates — that accumulate as water percolates through the sediments. The marine origin and mineral-rich character of Long Island's subsurface geology naturally produce a hard water supply, typical of the region.

At the hard hardness level, residents may experience scale buildup on fixtures, reduced soap lather, and decreased efficiency in water heaters and dishwashers; hard water can shorten appliance lifespan and increase maintenance needs. Regular descaling of showerheads and faucets is recommended, and homeowners benefit from point-of-use filters or whole-house water softeners, particularly for high-use appliances. Tap water meets all EPA Maximum Contaminant Level Goals, with over 100 contaminants tested within safe levels, and the water is considered safe to drink.

Geology & Source: Nassau County, Long Island; Quaternary glacial deposits overlying Cretaceous sand and clay formations; calcium and magnesium from marine sediments produce hard supply typical of Long Island hydrogeology

Other New York Water Reports

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Frequently Asked Questions

Is Franklin Square's water safe to drink?
Yes. Franklin Square's water meets all federal safety standards. The hardness is ≈ 120–179 mg/L (Hard), which is safe to drink. High hardness affects appliances and taste, but poses no health risk.
Do I need a water softener in Franklin Square?
At ≈ 120–179 mg/L (Hard), Franklin Square's water will cause significant limescale on kettles, washing machines, and water heaters. A water softener or descaler is strongly recommended to extend appliance lifespan and reduce energy bills by up to 20%.
How does Franklin Square compare to the USA average?
The USA national average is 151 mg/L. Franklin Square (≈ 120–179 mg/L) is 1 mg/L below the national average. The softest major city is Scarsdale at just 0.02 mg/L.

Data Sources & Methodology

Water quality data for Franklin Square is derived from geographic and geological modelling of the surrounding region. No federal monitoring station data was available for this location.

Estimated

Water Hardness

Modelled estimate based on state-level USGS geological survey data for this region. No direct USGS Water Quality Portal measurement was matched to this city — the value reflects a statistical range calibrated to the state's dominant rock types and typical source water characteristics.

Estimated

pH

Estimated from regional geology and source water characteristics. pH is correlated with water hardness and local bedrock — values may differ from utility-reported figures.

Estimated

TDS — Total Dissolved Solids

Estimated using a derived ratio from water hardness and regional conductance profiles. TDS in natural water correlates strongly with total mineral content including hardness ions.

Measured

PFAS — Perfluoroalkyl and Polyfluoroalkyl Substances

EPA UCMR5 (5th Unregulated Contaminant Monitoring Rule, 2023–2025) — sum of PFAS compounds detected at the public water system serving this city. A value of 0 indicates the system was sampled with no detection above reporting limits.

Modelled

Lead

Modelled estimate based on the EPA Lead and Copper Rule 90th-percentile tap-sample methodology. No publicly available per-city lead dataset with sufficient national coverage exists. Values are a conservative baseline derived from city population tier and infrastructure age — all estimates are maintained below the EPA action level of 0.015 mg/L.

Calculated

Appliance Lifespan

Calculated from water hardness using a linear degradation model. Baseline lifespans represent soft-water performance (kettle: 8.5 yrs, washing machine: 12.0 yrs, water heater: 15.0 yrs). Hard water mineral scale progressively reduces operational life in direct proportion to hardness concentration.