Unlike many cities its size in IL, Joliet keeps health-based violation rates low - systems here score at or above the state average for tap water safety, with no systemic concerns flagged in the current data set.

Data: EPA SDWIS

Water Quality Map: Joliet, IL

Each dot represents a ZIP code. Color indicates water quality grade. Tap a dot for details.

A B C D F

Overview

We track home safety data for 6 ZIP codes in Joliet, Illinois (population ~130,147), covering 13 community water systems serving approximately 257,552 people region-wide. The EPA snapshots used for this build directly map water systems to 5 of 6 ZIP codes.

5 of 5 ZIP codes with a reported violation count in the available EPA record (100%) have recorded EPA violations. 4 health-based violations appear in the available health breakdown.

Home Safety Score

Average Home Safety Score for Joliet: B (70/100)

Model 4.0.0 uses four measured components across three equally weighted domains. If a required domain is unavailable, no score is published:

Factor	What It Measures
Water Quality	EPA violations and compliance history
PFAS MCL Screen	UCMR 5 testing against the covered federal MCLs
Radon Risk	EPA radon zone classification
Annual AQI	EPA AirData county-year median with at least 90 observed days

Water Sources

Joliet water systems draw from: Groundwater, Surface water.

Lead & Copper

• Average lead level (90th percentile): 0.0065 mg/L (EPA action level: 0.015 mg/L)
• 0 of 5 ZIP codes with known status exceed the EPA lead action level

Radon Risk

Dominant radon zone: Zone 2 (Moderate Risk)

• Zone 1 (High): 0 ZIP codes
• Zone 2 (Moderate): 6 ZIP codes
• Zone 3 (Low): 0 ZIP codes

The EPA recommends testing homes in Zone 1 and Zone 2 areas for radon.

Top Contaminants

Areas with Most Violations

All ZIP Codes in Joliet

• 60431 [C] - 53 violations ⚠
• 60432 [B] - 47 violations ⚠
• 60433 [C] - 61 violations ⚠
• 60434
• 60435 [B] - 45 violations ⚠
• 60436 [C] - 53 violations ⚠

Data Sources

• Water quality: EPA Safe Drinking Water Information System (SDWIS)
• Lead/copper: EPA Lead and Copper Rule sampling data
• Radon: EPA Map of Radon Zones

Reporting periods vary by source. Missing data is shown as unavailable, not as zero.

Housing Age Profile

Reading the housing age data for Joliet - median build year 1970 - the overriding implication is that the plumbing materials inside a typical home here reflect pre-1986 construction standards. In practical terms, that means lead-soldered copper joints are common across much of the housing stock. Where those materials are present, water can leach lead as it moves through joints - a pathway that corrosion control treatment under federal rules is designed to reduce, though it cannot eliminate lead risk where the plumbing materials themselves contain lead.

1970

Median Year Built

70%

Pre-1986 (Lead Paint Risk)

41%

Pre-1970 (Lead Pipes Risk)

Pre-1970 (41%) 1970–1986 (29%) Post-1986 (30%)

Over half of homes in Joliet were built before 1986, when lead solder was banned. Older plumbing may leach lead into drinking water, especially with corrosive water chemistry.

Source: U.S. Census Bureau ACS B25034.

Joliet: Remediation Cost in Perspective

The household financial perspective in Joliet reflects a moderate cost-to-value ratio - an equity share that is not trivially small but remains within the range where most homeowners can address documented water and safety issues by treating the expense as a real line item in property planning rather than a discretionary one.

Median Home Value

$185,100

Est. Remediation

$2,650

Remediation as % of home value 1.4%

Remediation costs are moderate relative to home values in Joliet. The estimated $1,383–$4,733 range is manageable for most homeowners but still worth budgeting for. Home values are 1% above the Illinois average.

Protecting Children from Lead in Joliet

70%

Homes Built Before 1986

0.0065

mg/L Avg Lead (Limit: 0.015)

Why children are most at risk: The CDC states there is no safe level of lead exposure for children. Children under 6 absorb lead more readily than adults, and even low levels can cause developmental delays, learning difficulties, and behavioral problems.

Pulling a tap sample fills the gap that utility data cannot close, particularly here where 70% of housing dates from the pre-rule era and citywide monitoring sits at or above the regulatory mark in Joliet.

Sources: EPA Lead and Copper Rule, U.S. Census Bureau ACS, CDC childhood lead poisoning prevention guidelines.

Historical Flood-Claim Evidence for Joliet

944

Total FEMA Flood Claims

$6,893

Avg Reported Sum With Payment Data

100%

A/V Share of Claim-Record ZIPs

Historical NFIP data for Joliet contains 944 flood insurance claims. Among claims with payment data, the average reported building, contents, and ICC component sum is $6,893. Among ZIP codes with claim records, 100% have an A- or V-family dominant rated zone recorded in those historical claims. This is not a complete current FEMA property-map inventory.

How flooding affects water quality: Flood events can introduce sewage, agricultural runoff, and industrial chemicals into water supplies. Even after floodwaters recede, contamination can persist in wells and aging infrastructure. The <strong>$2,650</strong> remediation estimate shown here excludes flood insurance and is not derived from NFIP claim count.

Claim count does not establish current property risk. Check the exact address in FEMA's current map and obtain a property-specific insurance quote when relevant.

Source: historical FEMA National Flood Insurance Program (NFIP) claim records. No current FEMA property-map designation is asserted.