Northfield
EPA ID: IL0312100 · 5,470 people served · 3 ZIP codes
ZipCheckup's reading of EPA records for Northfield (IL0312100): 1 violation recorded with unresolved status in the SDWIS data used. Marked active and unresolved in the EPA record: 1 violation at Northfield, whose service population is approximately 5,470 residents.
Data: EPA SDWIS
Service Area Map
Coverage area for Northfield Source: EPA SDWIS service area boundaries.
Service area boundary
Demographics of ZIP Codes Served
The ZIP codes associated with Northfield have a median household income of $190,250 and about 89,192 residents live in those ZIP codes (Census; not the number of people this system supplies). Approximately 77% of housing stock was built before 1986, which increases the likelihood of lead service lines and older plumbing.
Environmental Justice Note: On average, 46% of census tracts in the counties mapped to this service area are designated disadvantaged by the federal Climate and Economic Justice Screening Tool (CEJST, 2022 version). 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?
Northfield's water is drawn from rivers, lakes, or reservoirs. Surface water sources are more exposed to agricultural runoff, stormwater, and upstream discharges, but they typically receive more intensive treatment before reaching your tap.
Infrastructure Risk
Comparable Water Systems
Similar-sized systems in Illinois
System Overview
Northfield (EPA ID: IL0312100) is a community water system in Illinois that serves approximately 5,470 people from surface water sources.
This system provides water to 3 ZIP codes across 3 communities.
Violation History
Status breakdown for accepted records with record years 2021-2026: 0 resolved, 0 archived, 0 addressed, and 1 unaddressed. Under this source contract, current noncompliance is the sum of addressed and unaddressed records. Archived and resolved records are excluded from current noncompliance.
Recent Violations
| Date | Contaminant | Type | Status |
|---|---|---|---|
| January 1, 2026 | Lead and Copper Rule | Non-health-based | Unaddressed (current) |
Contaminants Detected
The following contaminants have been flagged in EPA records for this water system:
| Contaminant | Category | Violations | Health-Based |
|---|---|---|---|
| Lead and Copper Rule | Monitoring & Reporting | 1 | No |
Lead & Copper
EPA Lead and Copper Rule evidence attributed directly to this water system:
| Lead Level | Exceeds Action Level | Sample Date |
|---|---|---|
| 0.017 mg/L | Yes | 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 Northfield (IL0312100) on EPA.gov.
Frequently Asked Questions
Is Northfield water safe to drink?
The accepted 2026Q2 ECHO snapshot shows 1 current noncompliance record and zero current records classified as health-based. That classification is not a property-specific water test or safety guarantee.
How many people does Northfield serve?
Northfield serves approximately 5,470 people across 3 ZIP codes in Illinois.
Where does Northfield get its water?
The primary water source is surface water.
Federal UCMR5 PFAS Monitoring: No PFAS Reported Above Reporting Levels
This water system was tested under the federal EPA Unregulated Contaminant Monitoring Rule (UCMR5). No PFAS compounds were reported above UCMR5 minimum reporting levels.
EPA's April 2024 PFAS rule sets MCLs of 4 ppt for PFOA and PFOS and 10 ppt for PFHxS, PFNA and HFPO-DA (GenX); water systems must comply from 2029. Other PFAS compounds have no individual federal MCL. A state standard is shown only where this system's state has its own enforceable PFAS limit. Detection results are EPA UCMR5 samples, not a measurement at your tap.
Source: U.S. EPA UCMR5 (Unregulated Contaminant Monitoring Rule, 5th cycle) — per-system federal sampling, 2023–2025. EPA UCMR5 monitoring program →
Frequently Asked Questions
How to cite this page
ZipCheckup. (n.d.). Northfield (IL): 1 EPA Violation. https://zipcheckup.com/water-system/il0312100/
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title = {{Northfield (IL): 1 EPA Violation}},
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url = {https://zipcheckup.com/water-system/il0312100/}
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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
Northfield (EPA ID: IL0312100) - request the latest Consumer Confidence Report or ask about specific contaminants.