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

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

Monroe Water Hardness & Quality Report (2026)

Water Hardness

hard

~120–179 mg/L

Hard

estimated · not lab-verified

Source

reservoir

pH Level

7.7

neutral = 7.0

Lead

0.005 mg/L

✓ Below action level

TDS

228.7 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 Monroe, your appliances are currently losing 20% efficiency due to mineral buildup.

Appliance	In Monroe	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 Monroe compares to its nearest neighbours

City	Hardness	PFAS (ppt)	Risk	Source
▶ Monroe, North Carolina	≈ 120–179 mg/L	98.9 ppt	🟠 Hard	reservoir
Indian Trail, North Carolina	≈ 0–60 mg/L	7 ppt	🟢 Soft	reservoir
Stallings, North Carolina	≈ 120–179 mg/L	6.7 ppt	🟠 Hard	reservoir
Waxhaw, North Carolina	≈ 0–60 mg/L	5.6 ppt	🟢 Soft	groundwater
Weddington, North Carolina	≈ 120–179 mg/L	5.8 ppt	🟠 Hard	reservoir

National Benchmark

How Monroe compares to the USA average

Benchmark	Hardness	Appliance Risk
▶ Monroe	≈ 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 Monroe's Water Unique?

Local geology and source profile

Source: ReservoirTDS: 228.7 mg/LpH: 7.7

The City of Monroe Water Resources Department, operating the John Glenn Water Treatment Plant, provides drinking water to residents in Monroe and surrounding areas of Union County, North Carolina, serving over 238,000 people through the Union County Water System. Primary sources are surface waters from three local reservoirs — Lake Twitty, Lake Lee, and Lake Monroe — with intermittent purchases from the Catawba River in South Carolina. Treated water is distributed citywide, from historic downtown near the courthouse to developments around Lake Monroe.

The supply originates in the Catawba River watershed within the Piedmont physiographic province, where ancient metamorphic rocks including gneiss and schist dominate alongside granitic intrusions of the Charlotte Belt. These felsic and mafic Precambrian to Paleozoic formations contribute dissolved minerals through weathering and soil leaching into the reservoirs, yielding a moderately mineralized supply. The system relies entirely on surface reservoirs capturing regional runoff, with mineral content shaped by igneous and metamorphic geology rather than the carbonate dissolution typical of limestone karst aquifers.

Monroe's moderately hard water promotes scale buildup in pipes, water heaters, and dishwashers, reducing efficiency and lifespan and potentially increasing energy costs by $1,380–$1,780 annually per household. Showers and fixtures may clog, and laundry feels less soft; regular vinegar descaling, low-flow aerators, and magnetic conditioners help, and a whole-home softener is recommended for high-usage homes. Water quality testing by the City and Union County Water System confirms compliance with federal standards for lead and copper, though 8 of 9 detected contaminants including Chromium-6 exceed stricter health advocacy guidelines; the 2023 and 2025 Annual Water Quality Reports confirm safe pH and disinfection via filtration and chlorination at the John Glenn plant, with PFAS data unavailable in current sources.

Geology & Source: Upper Catawba River watershed Piedmont terrain — Precambrian to Paleozoic gneiss, schist, and granitic formations of the Charlotte Belt; mineral weathering from felsic/mafic rocks yields moderate hardness

Other North Carolina Water Reports

Indian Trail

≈ 0–60 mg/L

🟢 Soft

Stallings

≈ 120–179 mg/L

🟠 Hard

Waxhaw

≈ 0–60 mg/L

🟢 Soft

Weddington

≈ 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 Monroe's water safe to drink?

Yes. Monroe'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 Monroe?

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

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