How does Union Square's water compare to the national average?

The USA national average is 151 mg/L. Union Square (≈ 120–179 mg/L) is 1 mg/L softer than average.

Union Square Water Hardness & Quality Report (2026)

Water Hardness

hard

~120–179 mg/L

Hard

estimated · not lab-verified

Source

reservoir

pH Level

7.6

neutral = 7.0

Lead

0.006 mg/L

✓ Below action level

TDS

172.8 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 Union Square, your appliances are currently losing 20% efficiency due to mineral buildup.

Appliance	In Union Square	Soft Water City	Efficiency 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 Union Square compares to its nearest neighbours

City	Hardness	PFAS (ppt)	Risk	Source
▶ Union Square, Massachusetts	≈ 120–179 mg/L	8.6 ppt	🟠 Hard	reservoir
Somerville, Massachusetts	≈ 0–60 mg/L	0 ppt	🟢 Soft	reservoir
Cambridge, Massachusetts	60 mg/L	18 ppt	🟡 Moderately Hard	reservoir
Mid-Cambridge, Massachusetts	60 mg/L	8.6 ppt	🟡 Moderately Hard	reservoir
Winter Hill, Massachusetts	≈ 0–60 mg/L	11.4 ppt	🟢 Soft	reservoir

National Benchmark

How Union Square compares to the USA average

Benchmark	Hardness	Appliance Risk
▶ Union Square	≈ 120–179 mg/L	🟠 Moderate
USA National Avg	151 mg/L	🟠 Moderate
Scarsdale Top Rated	0.02 mg/L	🟢 None

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What Makes Union Square's Water Unique?

Local geology and source profile

Source: ReservoirTDS: 172.8 mg/LpH: 7.6

Union Square, Somerville, Massachusetts, receives its water from the Somerville Water Department. This supply primarily draws from local groundwater wells within Middlesex County, with Massachusetts Water Resources Authority (MWRA) providing backup. Key sources include the Spot Pond area reservoirs managed by MWRA, alongside direct wellfields tapping the local aquifer. Water undergoes treatment at the MWRA John J. Carroll Water Treatment Plant in Marlborough, where processes like chlorination, fluoridation, and corrosion control are applied before distribution to roughly 80,000 residents.

The groundwater originates from aquifers influenced by eastern Massachusetts glacial till and bedrock, specifically the Cambridge Argillite and Lynn Volcanic Complex formations dating back to the Ordovician period. These ancient rocks, covered by Quaternary glacial deposits, contribute dissolved minerals. The water's soft to moderate mineral content stems from limited contact with highly calcareous rock types, unlike areas in western New England.

Homeowners in Union Square may notice scale buildup on fixtures and inside appliances like water heaters and dishwashers, which can decrease their efficiency and lifespan. Detergent may not lather as effectively in moderately hard water. Simple solutions include regular descaling with vinegar and installing low-flow fixtures. For persistent issues or to improve lathering and protect sensitive skin, a water softener is often a worthwhile investment. The water's pH is typically kept between 8.5 and 9.5 through lime addition for corrosion control.

Geology & Source: Eastern Massachusetts glacial till and bedrock aquifers; Cambridge Argillite and Lynn Volcanic Complex; moderate hardness from limited calcareous strata contact.

Other Massachusetts Water Reports

Somerville

≈ 0–60 mg/L

🟢 Soft

Cambridge

60 mg/L

🟡 Moderately Hard

Mid-Cambridge

60 mg/L

🟡 Moderately Hard

Winter Hill

≈ 0–60 mg/L

🟢 Soft

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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 Union Square's water safe to drink?

Yes. Union 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 Union Square?

At ≈ 120–179 mg/L (Hard), Union 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 Union Square compare to the USA average?

The USA national average is 151 mg/L. Union 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 Union 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

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.