WaterVerge

Is Wilmette, IL Tap Water Safe to Drink?

Graded A, with 2 unresolved violations on record. See what was cited — and what it means for your tap. What to do next ↓

27K residents served 1 water system PWSID: IL0313300
Overall Score
90.2 / 100
Violations
2 active
Last Updated
May 2026
Source
Surface water
#146 of 891 in Illinois Top 15% nationally
Local Government
High data confidence
Reviewed by WaterVerge Editorial Team · Last updated May 2026
AGRADE
Water Quality Grade
90.2/100
waterverge.com
A 90.2/100

Wilmette, IL — Water Quality Report

Wilmette's drinking water received a grade of A (90.2 out of 100), indicating excellent water quality. The city's 1 water system serves approximately 27,087 residents using surface water.

Lead levels were measured at 0.5 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 0 health-based violations. 2 remain unresolved.

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

What to know about Wilmette's water

Wilmette ranks #146 out of 891 cities in Illinois for water quality, placing it above 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.

Quality Breakdown

Water quality score

See methodology →
90.2 out of 100 Grade A
A: 90-100
B: 74-89
C: 60-73
F: <50
How is this calculated?
Violations
40.3/45
B
Historical violation record including health-based and monitoring violations.
Lead & Copper
20/20
A
Lead at 0.5 ppb (90th percentile).
Contaminants
17.9/20
B
No PFAS compounds detected.
Compliance
8/10
B
Monitoring and reporting compliance with EPA regulations.
Source Risk
4/5
B
Water source: Surface water.
Water Safety

Is Wilmette, IL water safe to drink?

Use Caution

Wilmette's tap water meets most EPA standards but has areas that warrant attention. With a grade of A (90.2/100), some contaminant levels or compliance issues suggest that residents may benefit from additional filtration. The city's 1 water system serves approximately 27,087 residents using surface water (rivers, lakes, or reservoirs).

2
Active Violations
0.5 ppb
Lead (90th %ile)
None
PFAS Detected
9 events
Disaster History

Recent water quality updates for Wilmette

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

Update
Water quality data updated

Latest EPA compliance and testing data incorporated into Wilmette's water quality assessment. Grade: A (90.2/100).

Violation
2 drinking water violations recorded

Contaminants: TTHM, Total Haloacetic Acids (HAA5).

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
8 drinking water violations recorded

Contaminants: Barium, Arsenic, Fluoride.

Key contaminant findings

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

Lead Within Limits
Detected: 0.5 ppb Limit: 15 ppb (EPA Action Level)

Well within EPA limits.

Violation history

Wilmette's water system has 13 total violations on record, including 0 health-based violations. 2 remain unresolved. 3 violations were issued in the last 5 years.

MROther
Most recent violations:
Oct 2025 TTHM Resolved
Oct 2025 Total Haloacetic Acids (HAA5) Resolved
Jul 2025 Consumer Confidence Rule Open
Jun 1979 Barium Resolved
Jun 1979 Arsenic 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 North Branch Chicago River, Skokie River, Wf Of Nb Chicago River, Nb Chicago River.

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 Wilmette's water come from?

Wilmette's drinking water comes from surface water (rivers, lakes, or reservoirs), supplied by 1 water system serving approximately 27,087 people. Surface water sources are more susceptible to contamination from runoff, industrial discharge, and algal blooms, requiring extensive treatment. Nearby water bodies include North Branch Chicago River (river), Skokie River (river), Wf Of Nb Chicago River (river), Nb Chicago River (river).

What Wilmette residents can do

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

Wilmette'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
0.5 ppb
EPA Action Level: 15 ppb · 3% of limit
Safe Level
HAA5 (Disinfection Byproducts)
Disinfection Byproduct
Safe
8.5 µg/L
EPA MCL: 60 µg/L · 14% of limit
Within LimitUCMR 4 DataHAA6Br: 6.5 µg/LHAA9: 14.1 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
132.5 µg/L
EPA Health Ref Level: 1,500 µg/L · 9% of limit
DetectedUCMR 3 Data
Vanadium
Inorganic
Detected
0.30 µg/L
EPA Short-term HA: 21 µg/L · 1% of limit
DetectedUCMR 3 Data
Chlorate
Disinfection Byproduct
Elevated
110.0 µg/L
EPA Lifetime HA: 210 µg/L · 52% of limit
DetectedUCMR 3 Data
Molybdenum
Inorganic
Detected
1.10 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

13
Total violations
0
Health-based
2
Active / unresolved
Oct 2025
Most recent violation
Compliance Record

Violations & advisories

13 Total
2 Active
0 Health-based
11 Resolved
Violations by category
Inorganic Chemicals
6
Stage 2 Disinfectants and Disinfection Byproducts Rule
2
Consumer Confidence Rule
1
Arsenic Rule
1
Nitrate Rule
1
Jul 2025 Active
Consumer Confidence Rule
Other Violation 0
Active
Compliance Violation
Monitoring 0
Oct 2025 Resolved
TTHM
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2025
Oct 2025 Resolved
Total Haloacetic Acids (HAA5)
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2025
Jun 1979 Resolved
Barium
Monitoring & Reporting
Monitoring & Reporting Resolved Jun 1980
Jun 1979 Resolved
Arsenic
Monitoring & Reporting
Monitoring & Reporting Resolved Jun 1980
Jun 1979 Resolved
Fluoride
Monitoring & Reporting
Monitoring & Reporting Resolved Jun 1980
Jun 1979 Resolved
Nitrate
Monitoring & Reporting
Monitoring & Reporting Resolved Jun 1980
Jun 1979 Resolved
Mercury
Monitoring & Reporting
Monitoring & Reporting Resolved Jun 1980
Jun 1979 Resolved
Cadmium
Monitoring & Reporting
Monitoring & Reporting Resolved Jun 1980
Jun 1979 Resolved
Chromium
Monitoring & Reporting
Monitoring & Reporting Resolved Jun 1980
Jun 1979 Resolved
Selenium
Monitoring & Reporting
Monitoring & Reporting Resolved Jun 1980
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 Wilmette

Industrial polluters nearby

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

Total reported releases to surface water: 1 lbs

FacilityTop chemicalTo surface water (lbs/yr)Distance
ACME ALLIANCE LLC
Primary Metals · ACME ALLIANCE LLC
NORTHBROOK, IL60062
Copper18.6 mi
RAHCO RUBBER INC.
Plastics and Rubber · NA
DES PLAINES, IL60018
9.0 mi
VCNA PRAIRIE LLC - YARD 1021
Nonmetallic Mineral Product · VCNA PRAIRIE LLC
GLENVIEW, IL60025
4.7 mi
JOHN CRANE INC.
Miscellaneous Manufacturing · JOHN CRANE INC
MORTON GROVE, IL60053
4.6 mi
REGIS TECHNOLOGIES INC.
Chemicals · NA
MORTON GROVE, IL60053
4.1 mi

Source: EPA Toxic Release Inventory (TRI) 2023

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

Full contaminants report

Contaminant Detected Level EPA Limit Unit Category Status
Lead (90th percentile) 0.5 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 8.1 ppb from 1992 (18.0 ppb) to 2025 (9.9 ppb).
Infrastructure

Water source & infrastructure

Primary Source
Surface Water
Operator
Local Government
Population Served
27,087
Water Systems
1
Water Source

Where Wilmette's water comes from

Surface Water

Wilmette'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 27,087 people through 1 water system.

Local Hydrology

Water bodies near Wilmette

Wilmette is located near 4 notable water bodies. As a surface water system, these water bodies may directly influence the city's drinking water supply.

North Branch Chicago River
river
Skokie River
river
Wf Of Nb Chicago River
river
Nb Chicago River
river
Infrastructure

Water systems serving Wilmette

System Name PWSID Population Source
WILMETTE IL0313300 27,087 SW
Regional Comparison

How Wilmette compares

Full Illinois rankings →

Wilmette's score of 90.2/100 is above the average of 56/100 among major Illinois cities. It outscores 9 of 10 nearby cities.

Wilmette (this city)
90.2
Chicago
35.2
Aurora
45.5
Joliet
38.5
Naperville
81.2
Champaign
91.9
Illinois avg
56
City Profile

About Wilmette, IL

Wikipedia →

Wilmette is a village in Cook County, Illinois, United States. Bordering Lake Michigan, Kenilworth, Winnetka, Skokie, Northfield, Glenview, and Evanston, Illinois, it is located 14 miles (23 km) north of Chicago's downtown district. Wilmette had a population of 28,170 at the 2020 census. The first and only Baháʼí House of Worship in North America is located in Wilmette. Wilmette is also home to Central Elementary School and Romona Elementary School, both recent recipients of the National Blue Ribbon award bestowed by the U.S. Department of Education.

Economic Profile
$183,750
Median Income
$769,744
Median Home Value
$1,918/mo
Median Rent
4.3%
Unemployment
Community
45.7
Median Age
1,987
People / sq mi
83.5%
College Educated
87.3%
Homeownership
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Frequently asked questions

Is Wilmette, IL tap water safe to drink?

Wilmette's water quality earned a grade of A (90.2/100). The water generally meets EPA standards and is considered safe for consumption. The city ranks #146 out of 891 cities tested in Illinois.

What contaminants are in Wilmette's water?

Lead was measured at 0.5 ppb (90th percentile). No PFAS compounds were detected. 13 violations are on record.

How is Wilmette'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 Wilmette?

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

Where does Wilmette's water come from?

Wilmette's water is sourced from Surface water. The city has 1 water system serving approximately 27,087 residents.

How does Wilmette's water compare to other cities?

Wilmette ranks #146 out of 891 cities in Illinois (better than 84% of state cities) and #2333 out of 15744 cities nationally (85th percentile). The grade of A reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.