C
64

Fair Water Quality

Thornton, IL 60476

Cook County · Population served: 24,333 · Data updated March 2026

Water Systems Serving This Area

🏔
SOUTH HOLLAND
Surface water · Pop. 22,000
PWSID: IL0312970
🏔
THORNTON
Surface water · Pop. 2,333
PWSID: IL0313090

Contaminants Detected

ContaminantDetected LevelEPA MCLHealth GuidelineStatus
Lead
14.0
15 ppb 1 ppb Warning

PFAS / Forever Chemicals

1 detected All below limits
CompoundLevelEPA MCLHealth GuidelineStatus
PFBA7.3 pptNo standard500 pptUnregulated

Violation History (Last 5 Years)

18Total (5yr)
5Health-Based
0Major

Water Quality Summary

Understanding Your Water in Thornton

Tap water quality in Thornton, Illinois (60476) receives an overall grade of C (Fair) with a score of 64 out of 100, based on analysis of EPA compliance data, contaminant testing, and violation history. This is 10 points below the Illinois state average of 74. Compared to the national average (75), this area scores significantly lower. The area is served by 2 water systems providing water to approximately 24,333 people, using surface water sources. Testing has found elevated levels of Lead that warrant attention. PFAS testing detected 1 compound, all currently below EPA limits. Over the past 5 years, water systems here have accumulated 18 violations, including 5 health-based violations.

Your Score 64/100 C
vs State 10 pts below Illinois avg (74)
vs National 11 pts below national avg (75)

What a Grade C Means

A score of 64/100 indicates fair water quality in Thornton, IL. While the water meets minimum federal standards, there are noteworthy concerns — either elevated contaminant levels approaching regulatory limits, a moderate violation history, or both. Residents may want to review specific contaminant data and consider targeted filtration, especially for sensitive groups like children and pregnant women.

Surface water: sourced from rivers, lakes, or reservoirs

Health Information

What These Contaminants Mean for You

⚠️

Lead in Your Water

Lead is a toxic metal that can leach from aging pipes and plumbing fixtures.

Health Effects

Even low levels of lead exposure can cause developmental delays in children, kidney damage, and cardiovascular effects in adults. The EPA action level is 15 ppb, but health experts recommend no safe level of lead in drinking water.

Common Sources

Lead enters water primarily through corrosion of lead service lines, lead solder, and brass fixtures — especially in homes built before 1986.

What You Can Do

If lead is detected above 1 ppb, consider using a certified lead-removal filter (NSF/ANSI 53) for drinking and cooking water. Run cold water for 30 seconds before use if water has been sitting in pipes.

Common Questions

Frequently Asked Questions

Tap water in Thornton, Illinois receives a grade of C (Fair) with a score of 64/100. While it generally meets minimum federal standards, there are some areas of concern including violation history or elevated contaminant levels. Sensitive populations (children, pregnant women, elderly) may want to consider additional filtration.

ZIP code 60476 is served by 2 water systems using surface water sources, providing water to approximately 24,333 people. Surface water systems are more susceptible to contamination from agricultural runoff, industrial discharge, and weather events, but typically undergo more extensive treatment including filtration and disinfection.

Lead was detected at 14.0 ppb in Thornton, Illinois. While this is below the EPA action level of 15 ppb, it exceeds the health guideline of 1 ppb recommended by health organizations. Consider a certified lead filter, especially if you have young children.

1 PFAS compound were detected in water serving Thornton, Illinois, but all are currently below EPA limits. While levels are within regulatory standards, some health organizations recommend minimizing any PFAS exposure. Activated carbon or reverse osmosis filters can reduce PFAS levels.

Water systems serving Thornton, Illinois have received 18 violations in the last 5 years, including 5 health-based violations. Violations can range from paperwork issues (monitoring & reporting) to serious health-based violations where contaminant levels exceeded safe limits. Review the violation details above for specifics.

Based on detected contaminants (lead, PFAS), residents in Thornton, Illinois should consider: Reverse osmosis (RO) system — most effective for PFAS, lead, and other contaminants. Always look for filters with NSF/ANSI certification for the specific contaminants you want to remove.

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