How does North Potomac's water compare to the national average?

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

North Potomac Water Hardness & Quality Report (2026)

Water Hardness

very hard

180+ mg/L

Very Hard

estimated · not lab-verified

Source

reservoir

pH Level

7.6

neutral = 7.0

Lead

0.005 mg/L

✓ Below action level

TDS

297.2 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 North Potomac, your appliances are currently losing 45% efficiency due to mineral buildup.

Appliance	In North Potomac	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 North Potomac compares to its nearest neighbours

City	Hardness	PFAS (ppt)	Risk	Source
▶ North Potomac, Maryland	≈ 180+ mg/L	7.6 ppt	🔴 Very Hard	reservoir
Travilah, Maryland	≈ 120–179 mg/L	7.4 ppt	🟠 Hard	reservoir
Potomac, Maryland	≈ 120–179 mg/L	6.1 ppt	🟠 Hard	groundwater
Gaithersburg, Maryland	≈ 120–179 mg/L	6.5 ppt	🟠 Hard	reservoir
Great Falls, Virginia	≈ 120–179 mg/L	8.8 ppt	🟠 Hard	reservoir

National Benchmark

How North Potomac compares to the USA average

Benchmark	Hardness	Appliance Risk
▶ North Potomac	≈ 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 North Potomac's Water Unique?

Local geology and source profile

Source: ReservoirTDS: 297.2 mg/LpH: 7.6

North Potomac, Maryland is served by WSSC Water (Washington Suburban Sanitary Commission), a regional utility providing drinking water to portions of Montgomery and Prince George's Counties. The primary source is the Potomac River, which feeds into WSSC's treatment facilities including the Potomac River Filtration Plant. These plants treat river water through conventional processes before distributing it to homes and businesses in North Potomac and surrounding communities.

The Potomac River watershed in this region includes parts of the Piedmont and Coastal Plain provinces, where the river drains areas underlain by Cambrian–Ordovician carbonate and siliciclastic rocks. Weathering of these carbonate-rich formations releases calcium and magnesium into the river, giving the supply a very hard character. The river's alluvial and terrace deposits further contribute to mineralised water as it flows toward the treatment plants.

At very hard water levels, North Potomac residents can expect significant scale buildup on showerheads, faucets, and heating elements in water heaters, dishwashers, and washing machines. Frequent descaling or vinegar-based cleaning is recommended, and a water softener is strongly advised to protect plumbing and extend appliance life. WSSC Water's annual Consumer Confidence Reports confirm treated Potomac River water meets all federal and state standards for lead, copper, and other regulated contaminants.

Geology & Source: Potomac River — Piedmont and Coastal Plain provinces; Cambrian–Ordovician carbonate and siliciclastic rocks weather and release calcium and magnesium ions into the river; very hard supply

Other Maryland Water Reports

Travilah

≈ 120–179 mg/L

🟠 Hard

Potomac

≈ 120–179 mg/L

🟠 Hard

Gaithersburg

≈ 120–179 mg/L

🟠 Hard

Great Falls

≈ 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 North Potomac's water safe to drink?

Yes. North Potomac'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 North Potomac?

At ≈ 180+ mg/L (Very Hard), North Potomac'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 North Potomac compare to the USA average?

The USA national average is 151 mg/L. North Potomac (≈ 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 North Potomac 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.