C
67

Fair Water Quality

Johnston City, IL 62951

Williamson County · Population served: 7,436 · Data updated March 2026

Water Systems Serving This Area

🏔
JOHNSTON CITY
Surface water · Pop. 3,509
PWSID: IL1990500
🏔
CORINTH PWD
Surface water · Pop. 3,927
PWSID: IL1995120

Contaminants Detected

ContaminantDetected LevelEPA MCLHealth GuidelineStatus
Lead
2.8
15 ppb 1 ppb Warning

PFAS / Forever Chemicals

2 detected All below limits
CompoundLevelEPA MCLHealth GuidelineStatus
PFBA5.6 pptNo standard500 pptUnregulated
PFBA5.2 pptNo standard500 pptUnregulated

Violation History (Last 5 Years)

14Total (5yr)
1Health-Based
5Major

Water Quality Summary

Understanding Your Water in Johnston City

Tap water quality in Johnston City, Illinois (62951) receives an overall grade of C (Fair) with a score of 67 out of 100, based on analysis of EPA compliance data, contaminant testing, and violation history. This is 7 points below the Illinois state average of 74. The area is served by 2 water systems providing water to approximately 7,436 people, using surface water sources. Testing has found elevated levels of Lead that warrant attention. PFAS testing detected 2 compounds, all currently below EPA limits. Over the past 5 years, water systems here have accumulated 14 violations, including 1 health-based violations.

Your Score 67/100 C
vs State 7 pts below Illinois avg (74)
vs National 8 pts below national avg (75)

What a Grade C Means

A score of 67/100 indicates fair water quality in Johnston City, 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 Johnston City, Illinois receives a grade of C (Fair) with a score of 67/100. 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 62951 is served by 2 water systems using surface water sources, providing water to approximately 7,436 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 2.8 ppb in Johnston City, 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.

2 PFAS compounds were detected in water serving Johnston City, 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 Johnston City, Illinois have received 14 violations in the last 5 years, including 1 health-based violation. 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 Johnston City, 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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