How does Syosset's water compare to the national average?

The USA national average is 151 mg/L. Syosset (≈ 180+ mg/L) is 189 mg/L harder than average.

Syosset Water Hardness & Quality Report (2026)

Water Hardness

very hard

180+ mg/L

Very Hard

estimated · not lab-verified

Source

groundwater

pH Level

7.9

neutral = 7.0

Lead

0.004 mg/L

✓ Below action level

TDS

222.5 mg/L

Est. Daily Cost

$0.91

energy & soap waste

Source: See methodology section below · Updated 2026

very hard180+ mg/LVery Hard · 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 Syosset, your appliances are currently losing 45% efficiency due to mineral buildup.

Appliance	In Syosset	Soft Water City	Efficiency Loss
Kettle	4.7 yrs	8.5 yrs	-45%
Washing Machine	6.6 yrs	12 yrs	-45%
Water Heater	8.3 yrs	15 yrs	-45%

Regional Water Comparison

How Syosset compares to its nearest neighbours

City	Hardness	PFAS (ppt)	Risk	Source
▶ Syosset, New York	≈ 180+ mg/L	449.8 ppt	🔴 Very Hard	groundwater
Jericho, New York	≈ 120–179 mg/L	6 ppt	🟠 Hard	reservoir
Plainview, New York	≈ 120–179 mg/L	3.2 ppt	🟠 Hard	reservoir
Hicksville, New York	≈ 120–179 mg/L	3.3 ppt	🟠 Hard	groundwater
Bethpage, New York	≈ 120–179 mg/L	23.8 ppt	🟠 Hard	groundwater

National Benchmark

How Syosset compares to the USA average

Benchmark	Hardness	Appliance Risk
▶ Syosset	≈ 180+ mg/L	🔴 High
USA National Avg	151 mg/L	🟠 Moderate
Scarsdale Top Rated	0.02 mg/L	🟢 None

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What Makes Syosset's Water Unique?

Local geology and source profile

Source: GroundwaterTDS: 222.5 mg/LpH: 7.9

The Suffolk County Water Authority (SCWA) provides water to Syosset, New York, in Nassau County on western Long Island, serving over 1.2 million people across Suffolk and parts of Nassau Counties through more than 80 treatment plants. Syosset's supply is sourced from local groundwater wells tapping the Magothy and Upper Glacial aquifers. No specific treatment plant is named for Syosset in available data, but SCWA operates extensive well fields with aeration, filtration, disinfection, and corrosion control at its facilities. Full reports are available at scwa.com.

Long Island's groundwater basins form the primary watershed, with no surface streams directly feeding Syosset's supply. The key aquifers are the unconfined Upper Glacial (water table) and confined Magothy, composed of quartz sands, gravels, and silts from Pleistocene glaciation over Cretaceous Raritan clays. Dolomitic limestone intrusions and carbonate-rich sediments dissolve to impart minerals, yielding a hard supply that buffers acidity but increases dissolved solids compared to New York's softer northern reservoirs.

At very hard levels, Syosset water causes significant scale buildup in pipes, water heaters, dishwashers, and washing machines, reducing efficiency by up to 50% and shortening appliance life. White deposits on fixtures and reduced soap lathering are common. Regular vinegar descaling for showerheads and coffee makers is advised; installing a whole-house water softener is strongly recommended to protect boilers, extend plumbing lifespan, and improve cleaning effectiveness. SCWA reports compliance with EPA standards, with all contaminants below health guidelines and pH typically 7.0–8.0.

Geology & Source: Magothy Aquifer and Upper Glacial Aquifer — Pleistocene glacial deposits over Cretaceous Raritan Formation sands and clays; dolomitic limestone lenses dissolve calcium and magnesium, producing hard supply

Other New York Water Reports

Jericho

≈ 120–179 mg/L

🟠 Hard

Plainview

≈ 120–179 mg/L

🟠 Hard

Hicksville

≈ 120–179 mg/L

🟠 Hard

Bethpage

≈ 120–179 mg/L

🟠 Hard

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Notice an error or missing data? Help us keep this page accurate. If you spot incorrect water hardness, outdated utility info, or missing details, please let us know.

All reports are reviewed by our team. Thank you for supporting data quality!

Frequently Asked Questions

Is Syosset's water safe to drink?

Yes. Syosset's water meets all federal safety standards. The hardness is ≈ 180+ mg/L (Very Hard), which is safe to drink. High hardness affects appliances and taste, but poses no health risk.

Do I need a water softener in Syosset?

At ≈ 180+ mg/L (Very Hard), Syosset'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 45%.

How does Syosset compare to the USA average?

The USA national average is 151 mg/L. Syosset (≈ 180+ mg/L) is 189 mg/L above the national average. The softest major city is Scarsdale at just 0.02 mg/L.

Data Sources & Methodology

Water quality data for Syosset 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

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.