Oak Lawn
EPA ID: IL0312220 · 58,362 people served · 5 ZIP codes
Tallying the federal enforcement file for Oak Lawn yields 1 open violation that have not been formally closed — each finding sits in the EPA database while the utility continues to deliver water to approximately 58,362 residents and works through the required corrective action process.
Data: EPA SDWIS Last verified: 2026-04-02
Service Area Map
Coverage area for Oak Lawn Source: EPA SDWIS service area boundaries.
Service area boundary — Grade B
Service Area Demographics
The Oak Lawn serves a community with a median household income of $67,972 and an estimated 110,099 residents across its service area. Approximately 77% of housing stock was built before 1986, which increases the likelihood of lead service lines and older plumbing.
Environmental Justice Note: 46% 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?
Oak Lawn'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.
About 1% of homes in Cook 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 Oak Lawn compares to EPA limits
What This Means For You
Surface Water Treatment Rule at 2 mg/L exceeds the EPA maximum of mg/L.
Stage 1 DBP Rule at 1 mg/L exceeds the EPA maximum of mg/L.
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
Oak Lawn (EPA ID: IL0312220) is a community water system in Illinois that serves approximately 58,362 people from surface water sources.
This system provides water to 5 ZIP codes across 4 communities.
Average Home Safety Score: B (75/100)
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 |
| July 1, 2023 | Surface Water Treatment Rule | Monitoring | Resolved |
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 | 2 | No |
| Stage 1 DBP Rule | Treatment Failure | 1 | No |
Lead & Copper
EPA Lead and Copper Rule sampling data for ZIP codes served by this system:
Radon Risk in Service Area
Dominant radon zone for ZIP codes served by this system: Zone 2 (Moderate 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: 4 ZIP codes confirmed via EPA Community Water System Service Area Boundaries v3 plus 1 additional ZIP inferred from SDWIS registry data. The EPA-confirmed set is the most reliable; SDWIS-inferred entries may be narrower than the real deployment area.
Data Sources
This report uses public data from the EPA Safe Drinking Water Information System (SDWIS). View the full compliance record for Oak Lawn (IL0312220) on EPA.gov.
Frequently Asked Questions
Is Oak Lawn water safe to drink?
Oak Lawn has only monitoring/reporting violations, which are procedural in nature. The system meets federal health-based standards.
How many people does Oak Lawn serve?
Oak Lawn serves approximately 58,362 people across 5 ZIP codes in Illinois.
Where does Oak Lawn get its water?
The primary water source is surface water.
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.
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
Oak Lawn (EPA ID: IL0312220) — request the latest Consumer Confidence Report or ask about specific contaminants.