Dekalb
EPA ID: IL0370100 · 45,000 people served · 3 ZIP codes
Unlike fully compliant utilities, Dekalb has 1 outstanding EPA violation for approximately 45,000 residents.
Data: EPA SDWIS Last verified: 2026-04-02
Service Area Map
Coverage area for Dekalb Source: EPA SDWIS service area boundaries.
Service area boundary — Grade D
Service Area Demographics
The Dekalb serves a community with a median household income of $79,506 and an estimated 68,781 residents across its service area. Approximately 50% of housing stock was built before 1986, which increases the likelihood of lead service lines and older plumbing.
💧 Where Does Your Water Come From?
Dekalb'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 DeKalb County, Illinois rely on private wells rather than public water systems. Private well owners are responsible for their own water testing and treatment.
Infrastructure Risk
Detected Contaminants
How Dekalb compares to EPA limits
What This Means For You
Surface Water Treatment Rule at 1 mg/L exceeds the EPA maximum of mg/L.
Consumer Confidence Report Rule at 1 mg/L exceeds the EPA maximum of mg/L.
Revised Total Coliform Rule at 1 presence exceeds the EPA maximum of presence.
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
Dekalb (EPA ID: IL0370100) is a community water system in Illinois that serves approximately 45,000 people from groundwater sources.
This system provides water to 3 ZIP codes across 3 communities.
Average Home Safety Score: D (42/100)
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 |
|---|---|---|---|
| July 1, 2025 | Surface Water Treatment Rule | Monitoring | Unresolved |
| October 1, 2023 | Consumer Confidence Report Rule | Monitoring | Resolved |
| October 1, 2023 | Revised Total Coliform Rule | Monitoring | Resolved |
Contaminants Detected
The following contaminants have been flagged in EPA records for this water system:
| Contaminant | Category | Violations | Health-Based |
|---|---|---|---|
| Gross Beta | Radionuclides | 1 | No |
| Surface Water Treatment Rule | Treatment Failure | 1 | No |
| Consumer Confidence Report Rule | Reporting Failure | 1 | No |
| Revised Total Coliform Rule | Microbiological | 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 |
|---|---|---|---|
| 60115 | 0.011 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
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 the full compliance record for Dekalb (IL0370100) on EPA.gov.
Frequently Asked Questions
Is Dekalb water safe to drink?
Dekalb has only monitoring/reporting violations, which are procedural in nature. The system meets federal health-based standards.
How many people does Dekalb serve?
Dekalb serves approximately 45,000 people across 3 ZIP codes in Illinois.
Where does Dekalb get its water?
The primary water source is groundwater.
Federal UCMR5 PFAS Monitoring: Tested Clean
This water system was tested under the federal EPA Unregulated Contaminant Monitoring Rule (UCMR5). No PFAS compounds were detected.
Current MCL reflects the lowest state-enforceable limit (NYS 10 ppt for PFOA/PFOS, effective August 2020). The federal final MCL of 4 ppt for PFOA/PFOS (EPA April 2024 rule) is not enforceable until April 2029. Detections above 4 ppt but below 10 ppt are below current MCL but above the future federal limit.
Source: U.S. EPA UCMR5 (Unregulated Contaminant Monitoring Rule, 5th cycle) — per-system federal sampling, 2023–2025. EPA UCMR5 monitoring program →
Lead Service Line Inventory
Service line breakdown reported under the federal Lead and Copper Rule Improvements (LCRI) inventory requirement:
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.
How Water Systems Appear in Rankings
Water systems are evaluated by violation history, contaminant detections, and service population. Larger systems with more service connections appear in more rankings.
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
Dekalb (EPA ID: IL0370100) — request the latest Consumer Confidence Report or ask about specific contaminants.