Henderson
EPA ID: IL0950250 · 375 people served · 1 ZIP code
Henderson's current EPA file includes 10 unresolved violations — every outstanding finding is documented in federal records for this utility, which supplies water to approximately 375 residents across its service territory.
Data: EPA SDWIS Last verified: 2026-04-02
Service Area Map
Coverage area for Henderson Source: EPA SDWIS service area boundaries.
Service area boundary — Grade C
Service Area Demographics
The Henderson serves a community with a median household income of $56,429 and an estimated 268 residents across its service area. Approximately 94% of housing stock was built before 1986, which increases the likelihood of lead service lines and older plumbing.
Environmental Justice Note: 56% of the population in this service area is classified as disadvantaged under EPA's EJScreen criteria. Communities with higher disadvantaged populations often face disproportionate environmental and health burdens, including aging water infrastructure and limited resources for remediation.
💧 Where Does Your Water Come From?
Henderson's water is pumped from underground aquifers. Groundwater is naturally filtered through rock and soil, but it can be vulnerable to PFAS contamination, nitrates from agriculture, and industrial chemicals that seep into the water table.
About 1% of homes in Knox County, Illinois rely on private wells rather than public water systems. Private well owners are responsible for their own water testing and treatment.
Superfund Proximity Note: This service area ranks in the 70th percentile nationally for proximity to Superfund (NPL) sites. Groundwater sources near contaminated sites may face elevated risk from industrial chemicals.
Infrastructure Risk
Detected Contaminants
How Henderson compares to EPA limits
What This Means For You
Total Trihalomethanes (TTHM) at 2 mg/L exceeds the EPA maximum of 0.08 mg/L. Bladder & rectal cancer risk; reproductive concerns. Consider granular activated carbon (GAC) filtration.
Haloacetic Acids (HAA5) at 1 mg/L exceeds the EPA maximum of 0.06 mg/L. Cancer risk; reproductive & developmental effects. Consider granular activated carbon (GAC) filtration.
Surface Water Treatment Rule at 4 mg/L exceeds the EPA maximum of mg/L.
Stage 2 DBP Rule at 3 mg/L exceeds the EPA maximum of mg/L.
Stage 1 DBP Rule at 1 mg/L exceeds the EPA maximum of mg/L.
PFAS Detected in Service Area
PFAS ("forever chemicals") have been detected in water serving this system's area. 5 detections recorded. 2 exceed federal EPA limits (4 ppt for PFOA/PFOS). 1 exceeds state limits.
Total Trihalomethanes (TTHM) was detected in this water system. granular activated carbon (GAC) filtration can reduce exposure.
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Estimated Remediation Costs
Average estimated costs across ZIP codes served by this system
Based on national averages for common remediation projects. Actual costs vary by property. Only issues flagged by EPA, FEMA, or state data for each ZIP code are included.
System Overview
Henderson (EPA ID: IL0950250) is a community water system in Illinois that serves approximately 375 people from groundwater sources.
This system serves ZIP code 61439 in Henderson.
Average Home Safety Score: C (66/100)
Based on water quality violations, lead levels, and radon risk across all ZIP codes served by this system.
Violation History
Recent Violations
| Date | Contaminant | Type | Status |
|---|---|---|---|
| August 22, 2025 | Lead and Copper Rule | Monitoring | Unresolved |
| July 2, 2025 | Stage 2 DBP Rule | Monitoring | Unresolved |
| July 1, 2025 | Surface Water Treatment Rule | Monitoring | Unresolved |
| January 1, 2025 | Total Trihalomethanes (TTHM) | Monitoring | Unresolved |
| October 17, 2024 | Stage 2 DBP Rule | Health-based | Unresolved |
| October 17, 2024 | Stage 2 DBP Rule | Monitoring | Unresolved |
| July 1, 2024 | Surface Water Treatment Rule | Monitoring | Unresolved |
| January 1, 2024 | Haloacetic Acids (HAA5) | Monitoring | Unresolved |
| July 1, 2023 | Surface Water Treatment Rule | Monitoring | Unresolved |
Contaminants Detected
The following contaminants have been flagged in EPA records for this water system:
| Contaminant | Category | Violations | Health-Based |
|---|---|---|---|
| Surface Water Treatment Rule | Treatment Failure | 4 | No |
| Stage 2 DBP Rule | Treatment Failure | 3 | Yes |
| Total Trihalomethanes (TTHM) | Disinfection Byproducts | 2 | No |
| Haloacetic Acids (HAA5) | Disinfection Byproducts | 1 | No |
| Stage 1 DBP Rule | Treatment Failure | 1 | No |
| Lead and Copper Rule | Treatment Failure | 1 | No |
Lead & Copper
EPA Lead and Copper Rule sampling data for ZIP codes served by this system:
| ZIP Code | Lead Level | Exceeds Limit | Sample Date |
|---|---|---|---|
| 61439 | 0.0006 mg/L | No | N/A |
Radon Risk in Service Area
Dominant radon zone for ZIP codes served by this system: Zone 1 (High Risk)
The EPA recommends testing homes in Zone 1 and Zone 2 areas for radon.
Need help with your water quality?
Typical cost: Water test: typically $20–$50 (DIY kit) · Professional inspection: $150–$400
Find the Right Water FilterFree tip: Let cold water run for 2 minutes before drinking — this helps flush lead from your pipes.
ZIP Codes Served
- 61439 — Henderson
Data Sources
This report uses public data from the EPA Safe Drinking Water Information System (SDWIS). View the full compliance record for Henderson (IL0950250) on EPA.gov.
Frequently Asked Questions
Is Henderson water safe to drink?
Henderson has recorded 1 health-based violation in the past 5 years. While the system is required to treat water to meet federal standards, you may want to consider additional precautions such as a certified water filter.
How many people does Henderson serve?
Henderson serves approximately 375 people across 1 ZIP code in Illinois.
Where does Henderson get its water?
The primary water source is groundwater.
Treatment regime
How this utility classifies its treatment process and what each reported treatment chemical does.
Treatment chemicals and what each one does
Chemical names are reported verbatim by the utility. Purpose categories are ZipCheckup annotations based on standard drinking-water treatment practice.
Treatment classification and chemical list sourced from HENDERSON Consumer Confidence Report.
Treatment intensity is a ZipCheckup-derived classification based on the chemicals and processes the utility reports. Chemicals and contamination sources are taken verbatim from the utility's CCR filing. Routine federal monitoring and contaminant testing shown elsewhere on this page determine whether the water meets safety standards, not the treatment classification.
Lead Service Line Inventory
Service line breakdown reported under the federal Lead and Copper Rule Improvements (LCRI) inventory requirement:
This system reports zero confirmed lead service lines in its inventory. Unknown-material counts may still warrant verification.
Federal LCRI rule (effective October 2024) requires every public water system to inventory its service lines and complete lead-line replacement within 10 years.
Source: EPA SDWIS Federal Service Line Inventory (Phase 2) · Submitted 2026
ZipCheckup is not affiliated with the utility or state agency. Inventory figures render verbatim from the public LCRI submission cited above; ZipCheckup does not perform inspections or replacements.
Frequently Asked Questions
What You Can Do
Test your water
Home test kits can detect lead, bacteria, and other contaminants at your tap. Find the right filter →
Check your specific ZIP code
Water quality can vary within a system. View nearest ZIP report →
Contact your utility
Henderson (EPA ID: IL0950250) — request the latest Consumer Confidence Report or ask about specific contaminants.