How does Lake Forest's water compare to the national average?

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

Lake Forest Water Hardness & Quality Report (2026)

Water Hardness

hard

~120–179 mg/L

Hard

estimated · not lab-verified

Source

river

pH Level

8.5

neutral = 7.0

Lead

0.008 mg/L

✓ Below action level

TDS

656.3 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 Lake Forest, your appliances are currently losing 20% efficiency due to mineral buildup.

Appliance	In Lake Forest	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 Lake Forest compares to its nearest neighbours

City	Hardness	Risk	Source
▶ Lake Forest, Illinois	≈ 120–179 mg/L	🟠 Hard	river
North Chicago, Illinois	≈ 120–179 mg/L	🟠 Hard	river
Highland Park, Illinois	≈ 120–179 mg/L	🟠 Hard	river
Deerfield, Illinois	≈ 120–179 mg/L	🟠 Hard	river
Waukegan, Illinois	130 mg/L	🟠 Hard	river

National Benchmark

How Lake Forest compares to the USA average

Benchmark	Hardness	Appliance Risk
▶ Lake Forest	≈ 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 Lake Forest's Water Unique?

Local geology and source profile

Source: RiverTDS: 656.3 mg/LpH: 8.5

Lake Forest Water Company provides drinking water to approximately 22,355 residents in Lake Forest, Illinois, within Lake County. The utility sources its supply exclusively from surface water originating from Lake Michigan, treated at facilities managed under Lake County Public Works. Contact details include phone 847-234-2600 at 220 E. Deerpath, Lake Forest, IL 60045. Annual Consumer Confidence Reports (CCRs) are published by Lake County Public Works and are accessible on their website for detailed compliance and monitoring data.

Lake Michigan's basin overlies Precambrian crystalline bedrock including granite and metamorphic rocks, capped by Paleozoic sedimentary layers such as Ordovician dolomite and limestone formations. Glacial tills and shoreline deposits from Pleistocene glaciation shape nearshore chemistry, contributing dissolved minerals through natural carbonate dissolution. Calcium and magnesium leach from these limestone-rich formations into the lake, imparting a hard supply character without extreme variability across the watershed.

Hard water causes scale buildup in appliances such as water heaters, dishwashers, and coffee makers, reducing efficiency and lifespan. Faucet aerators and pipes may clog over time, increasing maintenance needs. Regular vinegar descaling, installing drain screens, and flushing heaters annually help mitigate issues. A water softener is recommended for households with noticeable spotting on dishes or a film on skin after bathing. Potential contaminants noted include organic compounds such as Benzo[a]pyrene, Desethylatrazine, Hexachlorobenzene, and Carbofuran; lead and copper compliance is maintained via corrosion control. Treatment involves conventional surface water processes including screening, coagulation, sedimentation, filtration, and disinfection; PFAS data is unavailable in current sources.

Geology & Source: Lake Michigan watershed; Precambrian granite and metamorphic bedrock capped by Paleozoic Ordovician dolomite and limestone — carbonate dissolution from glacial tills yields hard surface water

Other Illinois Water Reports

North Chicago

≈ 120–179 mg/L

🟠 Hard

Highland Park

≈ 120–179 mg/L

🟠 Hard

Deerfield

≈ 120–179 mg/L

🟠 Hard

Waukegan

130 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 Lake Forest's water safe to drink?

Yes. Lake Forest'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 Lake Forest?

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

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