WaterVerge

Is Oak Lawn, IL Tap Water Safe to Drink?

Graded B, with 7 unresolved violations on record. See what was cited — and what it means for your tap. What to do next ↓

58K residents served 1 water system PWSID: IL0312220
Overall Score
75.4 / 100
Violations
7 active
Last Updated
May 2026
Source
Purchased surface water
#665 of 891 in Illinois Top 61% nationally
Local Government
High data confidence
Reviewed by WaterVerge Editorial Team · Last updated May 2026
BGRADE
Water Quality Grade
75.4/100
waterverge.com
B 75.4/100

Oak Lawn, IL — Water Quality Report

Oak Lawn's drinking water received a grade of B (75.4 out of 100), indicating good water quality. The city's 1 water system serves approximately 58,362 residents using purchased surface water.

Lead levels were measured at 11.6 ppb (90th percentile), which is within EPA limits but above recommended levels. PFAS testing under UCMR 5 found no detectable forever chemicals.

The system has 11 violations on record, including 2 health-based violations. 7 remain unresolved.

Data last updated: May 2026 · Source: EPA SDWIS, UCMR 5
Analysis

What to know about Oak Lawn's water

Oak Lawn ranks #665 out of 891 cities in Illinois for water quality, placing it below average in the state.

The city draws from surface water sources, which are more susceptible to seasonal runoff and agricultural contamination, requiring extensive multi-barrier treatment including coagulation, filtration, and disinfection.

Hexavalent chromium (chromium-6) was detected at 0.21 µg/L in UCMR 3 testing. While below California's 10 µg/L limit and with no federal MCL set, residents sensitive to this contaminant may consider reverse osmosis filtration.

While lead levels are within EPA limits, they are above the recommended 5 ppb threshold that health organizations consider ideal. A point-of-use filter adds an extra layer of protection.

Quality Breakdown

Water quality score

See methodology →
75.4 out of 100 Grade B
A: 90-100
B: 74-89
C: 60-73
F: <50
How is this calculated?
Violations
39.4/45
B
Historical violation record including health-based and monitoring violations.
Lead & Copper
13/20
C
Lead at 11.6 ppb (90th percentile).
Contaminants
19/20
A
No PFAS compounds detected.
Compliance
0/10
F
Monitoring and reporting compliance with EPA regulations.
Source Risk
4/5
B
Water source: Purchased surface water.
Water Safety

Is Oak Lawn, IL water safe to drink?

Concerns Identified

Oak Lawn's drinking water has significant quality concerns based on EPA testing data. With a grade of B (75.4/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 1 water system serves approximately 58,362 residents using surface water (rivers, lakes, or reservoirs).

7
Active Violations
11.6 ppb
Lead (90th %ile)
None
PFAS Detected
9 events
Disaster History

Recent water quality updates for Oak Lawn

A timeline of significant water quality events, violations, and data updates.

Update
Water quality data updated

Latest EPA compliance and testing data incorporated into Oak Lawn's water quality assessment. Grade: B (75.4/100).

Violation
1 drinking water violation recorded

Contaminants: Consumer Confidence Rule.

Disaster
SEVERE STORMS, TORNADOES, STRAIGHT-LINE WINDS, AND FLOODNG

Federal disaster declaration (FEMA DR-4819). Flood event — may have impacted local water infrastructure.

Disaster
SEVERE STORMS AND FLOODING

Federal disaster declaration (FEMA DR-4749). Flood event — may have impacted local water infrastructure.

Violation
1 drinking water violation recorded

Contaminants: Consumer Confidence Rule.

Violation
1 drinking water violation recorded

Contaminants: Lead and Copper Rule.

Key contaminant findings

Based on the most recent EPA sampling data for Oak Lawn's water supply.

Lead Elevated
Detected: 11.6 ppb Limit: 15 ppb (EPA Action Level)

Within EPA limits but above the American Academy of Pediatrics recommended level of 1 ppb. An NSF 53-certified filter provides additional protection.

Violation history

Oak Lawn's water system has 11 total violations on record, including 2 health-based violations. 7 remain unresolved. 3 violations were issued in the last 5 years.

OtherMRTT
Most recent violations:
Jul 2025 Consumer Confidence Rule Open
Jul 2023 Consumer Confidence Rule Open
Dec 2022 Lead and Copper Rule Open
Jul 2016 Consumer Confidence Rule Open
Sep 2015 Coliform (TCR) Resolved

Flood & environmental risk

Cook County has experienced 9 federally declared disasters since 1972. Flooding and severe storms can overwhelm water treatment plants, cause sewage overflows, and introduce agricultural runoff, bacteria, and sediment into drinking water supplies. Local water sources include Salt Creek, Des Plaines River, Flag Creek, Chicago S & S Canal, Chicago Sanitary And Ship Canal.

SEVERE STORMS, TORNADOES, STRAIGHT-LINE WINDS, AND FLOODNG
Flood FEMA DR-4819
SEVERE STORMS AND FLOODING
Flood FEMA DR-4749
SEVERE STORMS, STRAIGHT-LINE WINDS, AND FLOODING
Flood FEMA DR-4116

Where does Oak Lawn's water come from?

Oak Lawn's drinking water comes from surface water (rivers, lakes, or reservoirs), supplied by 1 water system serving approximately 58,362 people. Surface water sources are more susceptible to contamination from runoff, industrial discharge, and algal blooms, requiring extensive treatment. Nearby water bodies include Salt Creek (river), Des Plaines River (river), Flag Creek (river), Chicago S & S Canal (river), Chicago Sanitary And Ship Canal (river).

What Oak Lawn residents can do

Install a water filter

Recommended: NSF-certified water filter. This addresses the specific contaminants found in Oak Lawn's water.

Request your utility's CCR

Your water utility is required to publish an annual Consumer Confidence Report (CCR) with detailed testing results. Ask for the latest copy or check your utility's website.

Flush your taps

Run cold water for 30 seconds before drinking, especially in the morning. Lead and copper leach from household plumbing when water sits in pipes.

Monitor alerts during storms

Oak Lawn's area has a history of flooding. After severe weather, watch for boil water advisories from your local utility.

Data: EPA SDWIS, UCMR 5 (PFAS), FEMA, NOAA. Last updated May 2026.

Contaminant Alerts

Top contaminants to know

View all ↓
Lead (90th percentile)
Inorganic / Heavy Metal
Near Limit
11.6 ppb
EPA Action Level: 15 ppb · 77% of limit
Near LimitFilter: NSF-53
HAA5 (Disinfection Byproducts)
Disinfection Byproduct
Safe
12.2 µg/L
EPA MCL: 60 µg/L · 20% of limit
Within LimitUCMR 4 DataHAA6Br: 9.0 µg/LHAA9: 19.9 µg/L
Chromium-6 (Hexavalent Chromium)
Inorganic
Detected
0.21 µg/L
CA MCL (no federal MCL): 10 µg/L · 2% of limit
DetectedUCMR 3 Data
Strontium
Inorganic
Detected
124.6 µg/L
EPA Health Ref Level: 1,500 µg/L · 8% of limit
DetectedUCMR 3 Data
Manganese
Inorganic
Detected
0.5 µg/L
EPA Secondary MCL: 50 µg/L · 1% of limit
DetectedUCMR 4 Data
Vanadium
Inorganic
Detected
0.30 µg/L
EPA Short-term HA: 21 µg/L · 1% of limit
DetectedUCMR 3 Data
Molybdenum
Inorganic
Detected
1.40 µg/L
EPA Lifetime HA: 40 µg/L · 3% of limit
DetectedUCMR 3 Data
PFAS Testing

Forever chemicals overview

National PFAS report →
30
Compounds tested
0
Detected
0
Exceed EPA MCL
Compliance Record

Violation summary

11
Total violations
2
Health-based
7
Active / unresolved
Jul 2025
Most recent violation
Compliance Record

Violations & advisories

11 Total
7 Active
2 Health-based
4 Resolved
Violations by category
Consumer Confidence Rule
3
Lead and Copper Rule
3
Total Coliform Rule
3
Stage 1 Disinfectants and Disinfection Byproducts Rule
1
Jul 2025 Active
Consumer Confidence Rule
Other Violation 0
Jul 2023 Active
Consumer Confidence Rule
Other Violation 0
Dec 2022 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
Jul 2016 Active
Consumer Confidence Rule
Other Violation 0
Jan 1993 Active
Lead and Copper Rule
Treatment Technique
Health-Based Health 0
Dec 1992 Active
Lead and Copper Rule
Treatment Technique
Health-Based Health 0
Active
Compliance Violation
Monitoring 0
Sep 2015 Resolved
Coliform (TCR)
Monitoring & Reporting
Monitoring & Reporting Resolved Sep 2015
Jul 2015 Resolved
Chlorine
Monitoring & Reporting
Monitoring & Reporting Resolved Sep 2015
Sep 2000 Resolved
Coliform (TCR)
Monitoring & Reporting
Monitoring & Reporting Resolved Sep 2000
Aug 1997 Resolved
Coliform (TCR)
Monitoring & Reporting
Monitoring & Reporting Resolved Aug 1997
Industrial pollution

Top industrial polluters within 10 miles of Oak Lawn

Industrial polluters nearby

Reported releases to surface water by facilities near Oak Lawn, ranked by pounds discharged annually.

Total reported releases to surface water: 97 lbs

FacilityTop chemicalTo surface water (lbs/yr)Distance
CLEVELAND-CLIFFS RIVERDALE LLC
Primary Metals · CLEVELAND-CLIFFS INC
RIVERDALE, IL60827
Manganese And Manganese Compounds908.0 mi
SIGNODE INDUSTRIAL GROUP LLC
Fabricated Metals · CROWN HOLDINGS INC
BRIDGEVIEW, IL60455
Lead And Lead Compounds74.5 mi
NORTHFIELD FOREST VIEW
Nonmetallic Mineral Product · CRH AMERICAS INC
BERWYN, IL60402
Lead06.5 mi
DUBOIS CHEMICALS INC. - BEDFORD PARK IL
Petroleum · DUBOIS CHEMICALS INC
BEDFORD PARK, IL60638
4.6 mi
MBAF - DIV OF G&W ELECTRIC
Primary Metals · NA
BLUE ISLAND, IL60406
4.3 mi

Source: EPA Toxic Release Inventory (TRI) 2023

Site context

Superfund sites within 10 miles of Oak Lawn

Superfund sites nearby

Federally tracked hazardous-waste sites on the EPA National Priorities List. Proximity does not necessarily indicate tap-water contamination — the connection depends on hydrology and treatment.

Source: EPA Superfund National Priorities List

Environmental Risk

Flood & disaster history

9
Declared disasters
Sep 2024
Most recent
Flood
Most common type

Cook County has experienced 9 federally declared disasters since 1972. Flooding and severe weather can compromise water treatment infrastructure and introduce contaminants into drinking water supplies.

Sep 2024
SEVERE STORMS, TORNADOES, STRAIGHT-LINE WINDS, AND FLOODNG
Flood FEMA #4819
Nov 2023
SEVERE STORMS AND FLOODING
Flood FEMA #4749
May 2013
SEVERE STORMS, STRAIGHT-LINE WINDS, AND FLOODING
Flood FEMA #4116
Sep 2005
HURRICANE KATRINA EVACUATION
Hurricane FEMA #3230
Jul 1993
SEVERE STORMS & FLOODING
Flood FEMA #997
Aug 1987
SEVERE STORMS & FLOODING
Flood FEMA #798

Recommended water filters

Based on contaminants detected in Oak Lawn's water supply, we recommend the following filter types.

🚰
For Lead
Reverse Osmosis or NSF 53-Certified Pitcher
Lead detected at 11.6 ppb
Read our guide →

Full contaminants report

Contaminant Detected Level EPA Limit Unit Category Status
Lead (90th percentile) 11.6 15 ppb Inorganic Near Limit
11Cl-PF3OUdS ND HI µg/L PFAS Not Detected
4:2 FTS ND HI µg/L PFAS Not Detected
6:2 FTS ND HI µg/L PFAS Not Detected
8:2 FTS ND HI µg/L PFAS Not Detected
9Cl-PF3ONS ND HI µg/L PFAS Not Detected
ADONA ND HI µg/L PFAS Not Detected
HFPO-DA ND 0.01 µg/L PFAS Not Detected
lithium ND HI µg/L PFAS Not Detected
NEtFOSAA ND HI µg/L PFAS Not Detected
NFDHA ND HI µg/L PFAS Not Detected
NMeFOSAA ND HI µg/L PFAS Not Detected
PFBA ND HI µg/L PFAS Not Detected
PFBS ND HI µg/L PFAS Not Detected
PFDA ND HI µg/L PFAS Not Detected
PFDoA ND HI µg/L PFAS Not Detected
PFEESA ND HI µg/L PFAS Not Detected
PFHpA ND HI µg/L PFAS Not Detected
PFHpS ND HI µg/L PFAS Not Detected
PFHxA ND HI µg/L PFAS Not Detected
PFHxS ND HI µg/L PFAS Not Detected
PFMBA ND HI µg/L PFAS Not Detected
PFMPA ND HI µg/L PFAS Not Detected
PFNA ND HI µg/L PFAS Not Detected
PFOA ND 0.004 µg/L PFAS Not Detected
PFOS ND 0.004 µg/L PFAS Not Detected
PFPeA ND HI µg/L PFAS Not Detected
PFPeS ND HI µg/L PFAS Not Detected
PFTA ND HI µg/L PFAS Not Detected
PFTrDA ND HI µg/L PFAS Not Detected
PFUnA ND HI µg/L PFAS Not Detected
Data source: EPA SDWIS, UCMR 5, local utility CCR.

Lead level trend (90th percentile)

EPA action level: 15 ppb
Lead has decreased by 23.0 ppb from 1992 (24.0 ppb) to 2025 (1.0 ppb).
Infrastructure

Water source & infrastructure

Primary Source
Purchased Surface Water
Operator
Local Government
Population Served
58,362
Water Systems
1
Water Source

Where Oak Lawn's water comes from

Purchased Surface Water

Oak Lawn's drinking water comes primarily from surface water sources such as rivers, lakes, or reservoirs.

Surface water systems require multi-stage treatment including coagulation, sedimentation, filtration, and disinfection to meet EPA Safe Drinking Water Act standards.

These sources can be impacted by seasonal changes, stormwater runoff, upstream agriculture, and industrial discharge.

The system is operated by local government ownership and serves approximately 58,362 people through 1 water system.

Local Hydrology

Water bodies near Oak Lawn

Oak Lawn is located near 5 notable water bodies. As a surface water system, these water bodies may directly influence the city's drinking water supply.

Salt Creek
river
Des Plaines River
river
Flag Creek
river
Chicago S & S Canal
river
Chicago Sanitary And Ship Canal
river
Infrastructure

Water systems serving Oak Lawn

System Name PWSID Population Source
OAK LAWN IL0312220 58,362 SWP
Regional Comparison

How Oak Lawn compares

Full Illinois rankings →

Oak Lawn's score of 75.4/100 is above the average of 56/100 among major Illinois cities. It outscores 7 of 10 nearby cities.

Oak Lawn (this city)
75.4
Chicago
35.2
Aurora
45.5
Joliet
38.5
Naperville
81.2
Champaign
91.9
Illinois avg
56
City Profile

About Oak Lawn, IL

Wikipedia →

Oak Lawn is a village in Cook County, Illinois, United States. The population was 58,362 at the 2020 census. Oak Lawn is a suburb of Chicago, located southwest of the city. It shares borders with the city in two areas but is surrounded mostly by other suburbs.

Economic Profile
$77,221
Median Income
$250,961
Median Home Value
$1,285/mo
Median Rent
5.8%
Unemployment
Community
41.1
Median Age
2,598
People / sq mi
29.3%
College Educated
81.9%
Homeownership
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Frequently asked questions

Is Oak Lawn, IL tap water safe to drink?

Oak Lawn's water quality earned a grade of B (75.4/100). Some concerns have been identified. Consider a water filter for an extra layer of protection. The city ranks #665 out of 891 cities tested in Illinois.

What contaminants are in Oak Lawn's water?

Lead was measured at 11.6 ppb (90th percentile). No PFAS compounds were detected. 11 violations are on record.

How is Oak Lawn's water quality grade calculated?

The grade is based on four factors: violation history (40%), lead and copper levels (25%), PFAS contamination (25%), and regulatory compliance (10%). The score is also adjusted based on how complete the available data is. See our methodology page for full details.

Do I need a water filter in Oak Lawn?

While lead levels are within EPA limits, a filter adds extra protection. Based on current data, basic filtration should suffice for additional peace of mind.

Where does Oak Lawn's water come from?

Oak Lawn's water is sourced from Purchased surface water. The city has 1 water system serving approximately 58,362 residents.

What health violations has Oak Lawn's water system had?

Oak Lawn has 2 health-based violations on record. The most recent violation was recorded in July 2025. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 7 violations remain unresolved.

How does Oak Lawn's water compare to other cities?

Oak Lawn ranks #665 out of 891 cities in Illinois (better than 25% of state cities) and #9580 out of 15744 cities nationally (39th percentile). The grade of B reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.