WaterVerge

Is Willowbrook, IL Tap Water Safe to Drink?

Graded B, with 8 unresolved violations on record. See what was cited — and what it means for your tap. What to do next ↓

9K residents served 1 water system PWSID: IL0431100
Overall Score
79.2 / 100
Violations
8 active
Last Updated
May 2026
Source
Purchased surface water
#586 of 891 in Illinois Top 53% nationally
Local Government
High data confidence
Reviewed by WaterVerge Editorial Team · Last updated May 2026
BGRADE
Water Quality Grade
79.2/100
waterverge.com
B 79.2/100

Willowbrook, IL — Water Quality Report

Willowbrook's drinking water received a grade of B (79.2 out of 100), indicating good water quality. The city's 1 water system serves approximately 9,000 residents using purchased surface water.

Lead levels were measured at 0.0 ppb (90th percentile), well within EPA limits. PFAS testing under UCMR 5 found no detectable forever chemicals.

The system has 13 violations on record, including 1 health-based violation. 8 remain unresolved.

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

What to know about Willowbrook's water

Willowbrook ranks #586 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.

The system has seen 7 violations in the past five years, suggesting a pattern of compliance challenges that residents should monitor closely.

Quality Breakdown

Water quality score

See methodology →
79.2 out of 100 Grade B
A: 90-100
B: 74-89
C: 60-73
F: <50
How is this calculated?
Violations
35.7/45
B
Historical violation record including health-based and monitoring violations.
Lead & Copper
20/20
A
Lead at 0.0 ppb (90th percentile).
Contaminants
19.5/20
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 Willowbrook, IL water safe to drink?

Concerns Identified

Willowbrook's drinking water has significant quality concerns based on EPA testing data. With a grade of B (79.2/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 1 water system serves approximately 9,000 residents using surface water (rivers, lakes, or reservoirs).

8
Active Violations
0.0 ppb
Lead (90th %ile)
None
PFAS Detected
5 events
Disaster History

Recent water quality updates for Willowbrook

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

Update
Water quality data updated

Latest EPA compliance and testing data incorporated into Willowbrook's water quality assessment. Grade: B (79.2/100).

Violation
2 drinking water violations recorded

Contaminants: LEAD AND COPPER RULE REVISIONS, Consumer Confidence Rule.

Violation
2 drinking water violations recorded

Contaminants: Total Haloacetic Acids (HAA5), TTHM.

Violation
1 drinking water violation recorded

Contaminants: Consumer Confidence Rule.

Disaster
SEVERE STORMS, STRAIGHT-LINE WINDS, AND FLOODING

Federal disaster declaration (FEMA DR-4116). Flood event — may have impacted local water infrastructure.

Disaster
HURRICANE KATRINA EVACUATION

Federal disaster declaration (FEMA DR-3230). Hurricane event — may have impacted local water infrastructure.

Key contaminant findings

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

Lead Within Limits
Detected: 0.0 ppb Limit: 15 ppb (EPA Action Level)

Well within EPA limits.

Violation history

Willowbrook's water system has 13 total violations on record, including 1 health-based violation. 8 remain unresolved. 7 violations were issued in the last 5 years.

RPTOtherMRMCL
Most recent violations:
Jul 2025 LEAD AND COPPER RULE REVISIONS Open
Jul 2025 Consumer Confidence Rule Open
Oct 2024 Total Haloacetic Acids (HAA5) Resolved
Oct 2024 TTHM Resolved
Jul 2023 Consumer Confidence Rule Open

Flood & environmental risk

DuPage County has experienced 5 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 Des Plaines River, Salt Creek, Addison Creek, Flag Creek, Sawmill Creek.

SEVERE STORMS, STRAIGHT-LINE WINDS, AND FLOODING
Flood FEMA DR-4116
HURRICANE KATRINA EVACUATION
Hurricane FEMA DR-3230
SEVERE STORMS & FLOODING
Flood FEMA DR-798

Where does Willowbrook's water come from?

Willowbrook's drinking water comes from surface water (rivers, lakes, or reservoirs), supplied by 1 water system serving approximately 9,000 people. Surface water sources are more susceptible to contamination from runoff, industrial discharge, and algal blooms, requiring extensive treatment. Nearby water bodies include Des Plaines River (river), Salt Creek (river), Addison Creek (river), Flag Creek (river), Sawmill Creek (river).

What Willowbrook residents can do

Install a water filter

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

Monitor alerts during storms

Willowbrook'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
Safe
0.0 ppb
EPA Action Level: 15 ppb · 0% of limit
Safe Level
PFAS Testing

Forever chemicals overview

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

Violation summary

13
Total violations
1
Health-based
8
Active / unresolved
Jul 2025
Most recent violation
Compliance Record

Violations & advisories

13 Total
8 Active
1 Health-based
5 Resolved
Violations by category
Consumer Confidence Rule
5
Stage 2 Disinfectants and Disinfection Byproducts Rule
2
Radionuclides and Revised Rad Rule
2
Lead and Copper Rule Revisions
1
Lead and Copper Rule
1
Jul 2025 Active
LEAD AND COPPER RULE REVISIONS
Reporting
Reporting 0
Jul 2025 Active
Consumer Confidence Rule
Other Violation 0
Jul 2023 Active
Consumer Confidence Rule
Other Violation 0
Jul 2022 Active
Consumer Confidence Rule
Other Violation 0
Jul 2021 Active
Consumer Confidence Rule
Other Violation 0
Dec 2020 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
Jul 2013 Active
Consumer Confidence Rule
Other Violation 0
Active
Compliance Violation
Monitoring 0
Oct 2024 Resolved
Total Haloacetic Acids (HAA5)
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2024
Oct 2024 Resolved
TTHM
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2024
Jul 1993 Resolved
Coliform (TCR)
Monitoring & Reporting
Monitoring & Reporting Resolved Jul 1993
Dec 1985 Resolved
Combined Radium (-226 and -228)
Max Contaminant Level
Health-Based Health Resolved Dec 1989
Jun 1977 Resolved
Gross Alpha, Excl. Radon and U
Monitoring & Reporting
Monitoring & Reporting Resolved Jun 1981
Industrial pollution

Top industrial polluters within 10 miles of Willowbrook

Industrial polluters nearby

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

Total reported releases to surface water: 32 lbs

FacilityTop chemicalTo surface water (lbs/yr)Distance
ELKAY PLUMBING PRODUCTS CO
Fabricated Metals · ZURN ELKAY WATER SOLUTIONS CORP
BROADVIEW, IL60155
Chromium167.6 mi
K.A. STEEL CHEMICALS INC. D/B/A OLIN CHLOR ALKALI PRODUCTS &
Chemicals · OLIN CORP
LEMONT, IL60439
Chlorine86.7 mi
SIGNODE INDUSTRIAL GROUP LLC
Fabricated Metals · CROWN HOLDINGS INC
BRIDGEVIEW, IL60455
Lead And Lead Compounds76.7 mi
ARROW GEAR
Machinery · PRECISION ARROW GEAR GROUP LLC
DOWNERS GROVE, IL60515
Lead15.4 mi
NORTHFIELD FOREST VIEW
Nonmetallic Mineral Product · CRH AMERICAS INC
BERWYN, IL60402
Lead08.7 mi

Source: EPA Toxic Release Inventory (TRI) 2023

Site context

Superfund sites within 10 miles of Willowbrook

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

5
Declared disasters
May 2013
Most recent
Flood
Most common type

DuPage County has experienced 5 federally declared disasters since 1972. Flooding and severe weather can compromise water treatment infrastructure and introduce contaminants into drinking water supplies.

May 2013
SEVERE STORMS, STRAIGHT-LINE WINDS, AND FLOODING
Flood FEMA #4116
Sep 2005
HURRICANE KATRINA EVACUATION
Hurricane FEMA #3230
Aug 1987
SEVERE STORMS & FLOODING
Flood FEMA #798
Jun 1974
SEVERE STORMS & FLOODING
Flood FEMA #438
Sep 1972
SEVERE STORMS & FLOODING
Flood FEMA #351

Full contaminants report

Contaminant Detected Level EPA Limit Unit Category Status
Lead (90th percentile) 0.0 15 ppb Inorganic Safe
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 13.0 ppb from 1992 (13.0 ppb) to 2025 (0.0 ppb).
Contaminant Rankings

See how Willowbrook compares by contaminant

Explore where Willowbrook ranks among all Illinois cities for specific contaminants.

Infrastructure

Water source & infrastructure

Primary Source
Purchased Surface Water
Operator
Local Government
Population Served
9,000
Water Systems
1
Water Source

Where Willowbrook's water comes from

Purchased Surface Water

Willowbrook'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 9,000 people through 1 water system.

Local Hydrology

Water bodies near Willowbrook

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

Des Plaines River
river
Salt Creek
river
Addison Creek
river
Flag Creek
river
Sawmill Creek
river
Infrastructure

Water systems serving Willowbrook

System Name PWSID Population Source
WILLOWBROOK IL0431100 9,000 SWP
Regional Comparison

How Willowbrook compares

Full Illinois rankings →

Willowbrook's score of 79.2/100 is above the average of 56/100 among major Illinois cities. It outscores 7 of 10 nearby cities.

Willowbrook (this city)
79.2
Chicago
35.2
Aurora
45.5
Joliet
38.5
Naperville
81.2
Champaign
91.9
Illinois avg
56
City Profile

About Willowbrook, IL

Economic Profile
$95,649
Median Income
$347,654
Median Home Value
$1,709/mo
Median Rent
3.9%
Unemployment
Community
47
Median Age
1,377
People / sq mi
54.8%
College Educated
74.4%
Homeownership
Share this reportHelp others learn about their water quality
WhatsAppXFacebookLinkedInEmail

Frequently asked questions

Is Willowbrook, IL tap water safe to drink?

Willowbrook's water quality earned a grade of B (79.2/100). Some concerns have been identified. Consider a water filter for an extra layer of protection. The city ranks #586 out of 891 cities tested in Illinois.

What contaminants are in Willowbrook's water?

Lead was measured at 0.0 ppb (90th percentile). No PFAS compounds were detected. 13 violations are on record.

How is Willowbrook'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 Willowbrook?

Based on current data, basic filtration should suffice for additional peace of mind.

Where does Willowbrook's water come from?

Willowbrook's water is sourced from Purchased surface water. The city has 1 water system serving approximately 9,000 residents.

What health violations has Willowbrook's water system had?

Willowbrook has 1 health-based violation 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. 8 violations remain unresolved.

How does Willowbrook's water compare to other cities?

Willowbrook ranks #586 out of 891 cities in Illinois (better than 34% of state cities) and #8332 out of 15744 cities nationally (47th percentile). The grade of B reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.