Joliet, IL: 42 Health Violations — 49/100 (2026)
6 ZIP codes · 10 water systems · Updated 2026-06-03
In recent EPA cycles, Joliet shows a persistent below-average water quality pattern within IL — documented violations span multiple service areas and have appeared consistently across reporting periods.
How Joliet Compares
Data: EPA SDWIS Last verified: 2026-06-03
Water Quality Map: Joliet, IL
Each dot represents a ZIP code. Color indicates water quality grade. Tap a dot for details.
Score Distribution
Distribution of water safety grades across Joliet.
Joliet Water: The Quick Version
- Your city's water systems recorded 306 violations in the past 5 years.
- Average lead level: 0.007 mg/L.
- Homes built before 1986: 70% — older plumbing may contain lead solder.
- Estimated remediation: $2,650 per household.
- CDC health risk index: 11.84.
Water Systems Serving Joliet
Joliet, IL draws its residential water from 3 separate providers among the 10 federally tracked systems. Each operates independently, with its own infrastructure, rate structure, and compliance record.
Overview
We track water quality and home safety data for 6 ZIP codes in Joliet, Illinois (population ~130,147), covering 10 community water systems serving approximately 257,095 people region-wide.
6 of 6 ZIP codes (100%) have recorded EPA violations. 42 health-based violations documented.
Home Safety Score
Average Home Safety Score for Joliet: D (49/100)
The score combines three factors:
| Factor | What It Measures |
|---|---|
| Water Quality | EPA violations and compliance history |
| Lead Levels | 90th percentile lead concentration vs EPA action level |
| Radon Risk | EPA radon zone classification |
Water Sources
Joliet water systems draw from: Groundwater, Surface water.
Lead & Copper
- Average lead level (90th percentile): 0.0070 mg/L (EPA action level: 0.015 mg/L)
- 0 ZIP codes 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
| Contaminant | Category | Violations | ZIPs Affected |
|---|---|---|---|
| Stage 2 DBP Rule | Treatment Technique | 63 | 6 |
| Surface Water Treatment Rule | Treatment Technique | 56 | 6 |
| Total Trihalomethanes (TTHM) | Disinfection Byproducts | 49 | 6 |
| Lead and Copper Rule | Treatment Technique | 49 | 6 |
| Revised Total Coliform Rule | Microbiological | 49 | 6 |
Areas with Most Violations
| ZIP Code | Safety Score | Violations | Health-Based | System |
|---|---|---|---|---|
| 60431 | D | 51 | 7 | Joliet |
| 60432 | D | 51 | 7 | Joliet |
| 60433 | D | 51 | 7 | Joliet |
| 60434 | C | 51 | 7 | Joliet |
| 60435 | D | 51 | 7 | Joliet |
| 60436 | D | 51 | 7 | Joliet |
All ZIP Codes in Joliet
- 60431 [D] — 51 violations ⚠
- 60432 [D] — 51 violations ⚠
- 60433 [D] — 51 violations ⚠
- 60434 [C] — 51 violations ⚠
- 60435 [D] — 51 violations ⚠
- 60436 [D] — 51 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
Updated daily.
CDC Health Data for Joliet
Source: CDC PLACES (County-level estimates). Water contamination can correlate with respiratory and chronic health conditions.
Compared to National Average
Vertical line = national average. ■ Above national · ■ Below national
Key Contaminants Detected in Joliet
Based on EPA violation records. Check your ZIP code report for system-specific contaminant data.
How Old Is Joliet's Housing Stock?
With 70% of homes built before 1986, lead solder in plumbing is a potential concern. The EPA banned lead solder in 1986, but many older homes retain original plumbing.
Source: U.S. Census Bureau American Community Survey (ACS).
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.
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.
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
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.
Climate-Related Water Risk for Joliet
Because Joliet's NFIP claim count reaches 943 and 100% of ZIP codes fall within FEMA-designated flood zones, flood exposure here operates differently than it does in lower-claim communities. In areas with isolated flood events, water-quality infrastructure can typically absorb the stress and recover between events. In communities with repeated high-volume flooding, treatment plants face recurring overload conditions, private wells in FEMA-designated zones accumulate repeated infiltration episodes, and distribution systems experience repeated pressure events that can drive backflow. The claim record for this area points to that second category: a flood environment where water infrastructure stress is periodic and documented, not theoretical.
Joliet has a significant flood history with 943 FEMA flood insurance claims on record, averaging $10,627 per claim. With 100% of ZIP codes in FEMA-designated flood zones, flood risk is a major concern for homeowners and water quality.
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. Flood damage can add significantly to the estimated <strong>$2,650</strong> remediation cost per household.
Residents in flood-prone areas should consider flood insurance even outside FEMA zones — over 25% of flood claims come from low-to-moderate risk areas. After any flood event, test your water before drinking.
Source: FEMA National Flood Insurance Program (NFIP) claims data, FEMA flood zone designations.
What You Can Do in Joliet
- Test your water at home. City-level data shows averages — your tap may differ. NSF-certified test kits cost $20-40 and give results in days.
- Install a certified water filter. Filters rated for Stage 2 DBP Rule can reduce the most common contaminant found in Joliet's water.
- Check your home's plumbing. With 70% of homes built before 1986, lead solder is a real possibility.
- Review your water system's CCR. Your utility publishes an annual Consumer Confidence Report with detailed test results. Request it or find it online.
Deep Dive Reports
Detailed analysis for Joliet, IL