Pekin Water Hardness & Quality Report (2026)
Water Hardness
27.5 grains per gallon
Source
groundwater
pH Level
8.2
neutral = 7.0
Lead
0.004 mg/L
✓ Below action level
TDS
352.5 mg/L
Est. Daily Cost
$1.00
energy & soap waste
Source: See methodology section below · Updated 2026
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 Pekin, your appliances are currently losing 45% efficiency due to mineral buildup.
| Appliance | In Pekin | Soft Water City | Efficiency Loss |
|---|---|---|---|
| Kettle | 1.5 yrs | 8.5 yrs | -82% |
| Washing Machine | 3 yrs | 12 yrs | -75% |
| Water Heater | 5 yrs | 15 yrs | -67% |
Regional Water Comparison
How Pekin compares to its nearest neighbours
| City | Hardness | PFAS (ppt) | Risk | Source |
|---|---|---|---|---|
| ▶ Pekin, Illinois | 470 mg/L | 6.2 ppt | 🔴 Very Hard | groundwater |
| East Peoria, Illinois | ≈ 180+ mg/L | 44.3 ppt | 🔴 Very Hard | groundwater |
| Peoria, Illinois | ≈ 180+ mg/L | 56 ppt | 🔴 Very Hard | groundwater |
| North Peoria, Illinois | ≈ 180+ mg/L | 8.5 ppt | 🔴 Very Hard | river |
| Morton, Illinois | 128.5 mg/L | 0 ppt | 🟠 Hard | groundwater |
National Benchmark
How Pekin compares to the USA average
| Benchmark | Hardness | Appliance Risk |
|---|---|---|
| ▶ Pekin | 470 mg/L | 🔴 High |
| USA National Avg | 151 mg/L | 🟠 Moderate |
| Scarsdale Top Rated | 0.02 mg/L | 🟢 None |
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What Makes Pekin's Water Unique?
Local geology and source profile
Illinois American Water (IL American – Pekin) serves the Pekin, Illinois community in Tazewell County, operating a groundwater-based supply system drawing from local aquifers rather than surface sources. Treatment facilities and distribution infrastructure serve the Pekin area; water quality inquiries can be directed to American Water's customer service at 1-800-422-2782 or locally at 1-309-566-4161. The Illinois EPA has determined that the North Pekin community water supply's source water is susceptible to contamination due to local hydrogeological conditions.
The Pekin water supply originates from groundwater in central Illinois, where Pennsylvanian-age bedrock and glacial deposits form the hydrogeological framework. Aquifer systems pass through limestone and dolomite formations that contribute high concentrations of naturally occurring calcium and magnesium minerals. This geological setting is typical of central Illinois and results in a very hard water supply at 470 mg/L — among the highest mineral content groundwaters in the state.
At very hard levels (470 mg/L), Pekin water causes significant scale buildup in water heaters, dishwashers, and washing machines, reducing appliance efficiency and lifespan substantially. Soap and detergent performance is greatly diminished, requiring higher product usage, and plumbing fixtures accumulate mineral deposits over time. A whole-home water softening system is strongly recommended — point-of-use treatment may be insufficient given the severity of hardness. The 2025 American Water Consumer Confidence Report confirms EPA nitrate compliance; sodium levels range 30.6–90 mg/L from natural deposits and softener regeneration. Residents with infants should consult the utility regarding nitrate levels.
Geology & Source: Central Illinois groundwater; Pennsylvanian-age bedrock and glacial deposits; limestone and dolomite aquifers dissolve calcium and magnesium — very hard character typical of central Illinois groundwater systems
Other Illinois Water Reports
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Frequently Asked Questions
Is Pekin's water safe to drink?
Do I need a water softener in Pekin?
How does Pekin compare to the USA average?
Data Sources & Methodology
Water quality data for Pekin is derived from geographic and geological modelling of the surrounding region. No federal monitoring station data was available for this location.
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.
pH
Estimated from regional geology and source water characteristics. pH is correlated with water hardness and local bedrock — values may differ from utility-reported figures.
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.
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.
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.
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.