Seneca
EPA ID: IL0991050 · 2,353 people served · 2 ZIP codes
ZipCheckup's reading of EPA records for Seneca (IL0991050): no drinking-water violations recorded since 2021. EPA lists no violations for Seneca, serving 2,353 people.
Data: EPA SDWIS
Service Area Map
Coverage area for Seneca Source: EPA SDWIS service area boundaries.
Service area boundary
Demographics of ZIP Codes Served
The ZIP codes associated with Seneca have a median household income of $86,516 and about 10,569 residents live in those ZIP codes (Census; not the number of people this system supplies). Approximately 62% of housing stock was built before 1986, which increases the likelihood of lead service lines and older plumbing.
💧 Where Does Your Water Come From?
Seneca's water is classified in EPA records as a groundwater source. 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.
Wastewater Proximity Note: This service area ranks in the 80th percentile nationally for proximity to wastewater discharge points.
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
Comparable Water Systems
Similar-sized systems in Illinois
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
Seneca (EPA ID: IL0991050) is a community water system in Illinois that serves approximately 2,353 people from groundwater sources.
This system provides water to 2 ZIP codes across 2 communities.
Violation History
Lead & Copper
EPA Lead and Copper Rule evidence attributed directly to this water system:
| Lead Level | Exceeds Action Level | Sample Date |
|---|---|---|
| Below the reporting limit | No | 2025-12-31 |
No copper action-level exceedance record appears for this PWSID in the accepted LCR snapshot. This does not establish a clean copper measurement.
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: Ask your water utility whether running cold water for 2 minutes is enough to flush your plumbing before drinking.
ZIP Codes Served
Coverage: Service area ZIP codes sourced from EPA Community Water System Service Area Boundaries v3 (March 2026 release). These ZIPs reflect the actual deployment footprint recorded by IL or modeled from parcel and building-footprint data.
Data Sources
This report uses public data from the EPA Safe Drinking Water Information System (SDWIS). View available EPA compliance records for Seneca (IL0991050) on EPA.gov.
Frequently Asked Questions
Is Seneca water safe to drink?
The accepted 2026Q2 ECHO snapshot contains zero violation records for Seneca in the inclusive 2021-2026 record-year window. This is a compliance-record finding, not a guarantee about water at a specific tap.
How many people does Seneca serve?
Seneca serves approximately 2,353 people across 2 ZIP codes in Illinois.
Where does Seneca get its water?
The primary water source is groundwater.
Frequently Asked Questions
How to cite this page
ZipCheckup. (n.d.). Seneca Water Quality Report, IL. https://zipcheckup.com/water-system/il0991050/
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author = {{ZipCheckup}},
title = {{Seneca Water Quality Report, IL}},
year = {n.d.},
url = {https://zipcheckup.com/water-system/il0991050/}
}