WaterVerge

Is Deerfield, IL Tap Water Safe to Drink?

Graded B, with 9 unresolved violations on record. See what was cited — and what it means for your tap. What to do next ↓

19K residents served 1 water system PWSID: IL0974340
Overall Score
76.9 / 100
Violations
9 active
Last Updated
May 2026
Source
Purchased surface water
#646 of 891 in Illinois Top 58% nationally
Local Government
High data confidence
Reviewed by WaterVerge Editorial Team · Last updated May 2026
BGRADE
Water Quality Grade
76.9/100
waterverge.com
B 76.9/100

Deerfield, IL — Water Quality Report

Deerfield's drinking water received a grade of B (76.9 out of 100), indicating good water quality. The city's 1 water system serves approximately 19,196 residents using purchased surface water.

Lead levels were measured at 9.4 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 15 violations on record, including 4 health-based violations. 9 remain unresolved.

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

What to know about Deerfield's water

Deerfield ranks #646 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 0.28 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 →
76.9 out of 100 Grade B
A: 90-100
B: 74-89
C: 60-73
F: <50
How is this calculated?
Violations
36.9/45
B
Historical violation record including health-based and monitoring violations.
Lead & Copper
13/20
C
Lead at 9.4 ppb (90th percentile).
Contaminants
20/20
A
No PFAS compounds detected.
Compliance
3/10
F
Monitoring and reporting compliance with EPA regulations.
Source Risk
4/5
B
Water source: Purchased surface water.
Water Safety

Is Deerfield, IL water safe to drink?

Concerns Identified

Deerfield's drinking water has significant quality concerns based on EPA testing data. With a grade of B (76.9/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 1 water system serves approximately 19,196 residents using surface water (rivers, lakes, or reservoirs).

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

Recent water quality updates for Deerfield

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

Update
Water quality data updated

Latest EPA compliance and testing data incorporated into Deerfield's water quality assessment. Grade: B (76.9/100).

Violation
1 drinking water violation recorded

Contaminants: 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 Deerfield's water supply.

Lead Elevated
Detected: 9.4 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

Deerfield's water system has 15 total violations on record, including 4 health-based violations. 9 remain unresolved. 5 violations were issued in the last 5 years.

OtherMRMCLTT
Most recent violations:
Jul 2025 Consumer Confidence Rule Open
Jan 2025 Total Haloacetic Acids (HAA5) Resolved
Jan 2025 TTHM Resolved
Jul 2023 Consumer Confidence Rule Open
Jul 2022 Consumer Confidence Rule Open

Flood & environmental risk

Lake County has experienced 5 federally declared disasters since 1973. 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, Buffalo Creek, Mc Donald Creek, Weller Creek, Des Plaines R.

SEVERE STORMS, STRAIGHT-LINE WINDS, AND FLOODING
Flood FEMA DR-4116
HURRICANE KATRINA EVACUATION
Hurricane FEMA DR-3230
SEVERE STORMS & FLOODING
Flood FEMA DR-997

Where does Deerfield's water come from?

Deerfield's drinking water comes from surface water (rivers, lakes, or reservoirs), supplied by 1 water system serving approximately 19,196 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), Buffalo Creek (river), Mc Donald Creek (river), Weller Creek (river), Des Plaines R (river).

What Deerfield residents can do

Install a water filter

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

Deerfield'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
9.4 ppb
EPA Action Level: 15 ppb · 63% of limit
Safe Level
HAA5 (Disinfection Byproducts)
Disinfection Byproduct
Safe
18.8 µg/L
EPA MCL: 60 µg/L · 31% of limit
Within LimitUCMR 4 DataHAA6Br: 11.2 µg/LHAA9: 28.6 µg/L
Chromium-6 (Hexavalent Chromium)
Inorganic
Detected
0.28 µg/L
CA MCL (no federal MCL): 10 µg/L · 3% of limit
DetectedUCMR 3 Data
Strontium
Inorganic
Detected
131.7 µg/L
EPA Health Ref Level: 1,500 µg/L · 9% of limit
DetectedUCMR 3 Data
1,4-Dioxane
Organic
Detected
0.08 µg/L
EPA Health Advisory: 0.35 µg/L · 23% 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

15
Total violations
4
Health-based
9
Active / unresolved
Jul 2025
Most recent violation
Compliance Record

Violations & advisories

15 Total
9 Active
4 Health-based
6 Resolved
Violations by category
Consumer Confidence Rule
6
Stage 2 Disinfectants and Disinfection Byproducts Rule
2
Total Coliform Rule
2
Lead and Copper Rule
2
Interim and Long Term 1 Enhanced Surface Water Treatment Rule
1
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 2019 Active
Consumer Confidence Rule
Other Violation 0
Jul 2018 Active
Consumer Confidence Rule
Other Violation 0
Jul 2014 Active
Consumer Confidence Rule
Other Violation 0
Oct 2005 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
Dec 1992 Active
Lead and Copper Rule
Treatment Technique
Health-Based Health 0
Active
Compliance Violation
Monitoring 0
Jan 2025 Resolved
Total Haloacetic Acids (HAA5)
Monitoring & Reporting
Monitoring & Reporting Resolved Mar 2025
Jan 2025 Resolved
TTHM
Monitoring & Reporting
Monitoring & Reporting Resolved Mar 2025
Aug 2013 Resolved
Coliform (TCR)
Max Contaminant Level
Health-Based Health Resolved Aug 2013
Aug 2013 Resolved
Coliform (TCR)
Max Contaminant Level
Health-Based Health Resolved Aug 2013
Apr 2005 Resolved
Interim Enhanced Surface Water Treatment Rule
Treatment Technique
Health-Based Health Resolved Apr 2005
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 Deerfield

Industrial polluters nearby

Reported releases to surface water by facilities near Deerfield, 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
Copper11.6 mi
NORTHFIELD BLOCK CO
Nonmetallic Mineral Product · CRH AMERICAS INC
MUNDELEIN, IL60060
Lead08.6 mi
VCNA PRAIRIE LLC - YARD 1021
Nonmetallic Mineral Product · VCNA PRAIRIE LLC
GLENVIEW, IL60025
5.0 mi
JESSUP MANUFACTURING CO
Textiles · JESSUP MANUFACTURING CO
LAKE BLUFF, IL60044
7.9 mi
OZINGA READY MIX CONCRETE INC
Nonmetallic Mineral Product · OZINGA BROS INC
LAKE BLUFF, IL60044
9.5 mi

Source: EPA Toxic Release Inventory (TRI) 2023

Environmental Risk

Flood & disaster history

5
Declared disasters
May 2013
Most recent
Flood
Most common type

Lake County has experienced 5 federally declared disasters since 1973. 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
Jul 1993
SEVERE STORMS & FLOODING
Flood FEMA #997
Oct 1986
SEVERE STORMS & FLOODING
Flood FEMA #776
Apr 1973
SEVERE STORMS & FLOODING
Flood FEMA #373

Recommended water filters

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

🚰
For Lead
Reverse Osmosis or NSF 53-Certified Pitcher
Lead detected at 9.4 ppb
Read our guide →

Full contaminants report

Contaminant Detected Level EPA Limit Unit Category Status
Lead (90th percentile) 9.4 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 34.0 ppb from 1992 (34.0 ppb) to 2025 (0.0 ppb).
Infrastructure

Water source & infrastructure

Primary Source
Purchased Surface Water
Operator
Local Government
Population Served
19,196
Water Systems
1
Water Source

Where Deerfield's water comes from

Purchased Surface Water

Deerfield'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 19,196 people through 1 water system.

Local Hydrology

Water bodies near Deerfield

Deerfield 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
Buffalo Creek
river
Mc Donald Creek
river
Weller Creek
river
Des Plaines R
river
Infrastructure

Water systems serving Deerfield

System Name PWSID Population Source
DEERFIELD IL0974340 19,196 SWP
Regional Comparison

How Deerfield compares

Full Illinois rankings →

Deerfield's score of 76.9/100 is above the average of 56/100 among major Illinois cities. It outscores 7 of 10 nearby cities.

Deerfield (this city)
76.9
Chicago
35.2
Aurora
45.5
Joliet
38.5
Naperville
81.2
Champaign
91.9
Illinois avg
56
City Profile

About Deerfield, IL

Wikipedia →

Deerfield is a village in Lake and Cook counties in the U.S. state of Illinois. A northern suburb of Chicago, Deerfield is located on the North Shore, about 28 miles (45 km) north of downtown Chicago. The population was 19,196 at the 2020 census.

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Frequently asked questions

Is Deerfield, IL tap water safe to drink?

Deerfield's water quality earned a grade of B (76.9/100). Some concerns have been identified. Consider a water filter for an extra layer of protection. The city ranks #646 out of 891 cities tested in Illinois.

What contaminants are in Deerfield's water?

Lead was measured at 9.4 ppb (90th percentile). No PFAS compounds were detected. 15 violations are on record.

How is Deerfield'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 Deerfield?

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 Deerfield's water come from?

Deerfield's water is sourced from Purchased surface water. The city has 1 water system serving approximately 19,196 residents.

What health violations has Deerfield's water system had?

Deerfield has 4 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. 9 violations remain unresolved.

How does Deerfield's water compare to other cities?

Deerfield ranks #646 out of 891 cities in Illinois (better than 27% of state cities) and #9149 out of 15744 cities nationally (42th percentile). The grade of B reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.