WaterVerge

Is Northfield, IL Tap Water Safe to Drink?

Graded B- — but Lead was detected above EPA limits. Here's what's in the water and how to remove it. What to do next ↓

5K residents served 1 water system PWSID: IL0312100
Overall Score
74.4 / 100
Violations
2 active
Last Updated
May 2026
Source
Purchased surface water
#685 of 891 in Illinois Top 63% nationally
Local Government
High data confidence
Reviewed by WaterVerge Editorial Team · Last updated May 2026
B-GRADE
Water Quality Grade
74.4/100
waterverge.com
B- 74.4/100

Northfield, IL — Water Quality Report

Northfield's drinking water received a grade of B- (74.4 out of 100), indicating fair water quality. The city's 1 water system serves approximately 5,470 residents using purchased surface water.

Lead levels were measured at 17.0 ppb (90th percentile), which exceeds the EPA action level of 15 ppb. PFAS testing under UCMR 5 found no detectable forever chemicals.

The system has 2 violations on record, including 1 health-based violation. 2 remain unresolved.

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

What to know about Northfield's water

Northfield ranks #685 out of 891 cities in Illinois for water quality, placing it among the lowest-rated 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.

Lead levels exceed the EPA action level of 15 ppb, which typically indicates aging lead service lines or lead solder in the distribution system. An NSF 53-certified filter is strongly recommended for drinking and cooking water.

Quality Breakdown

Water quality score

See methodology →
74.4 out of 100 Grade B-
A: 90-100
B: 74-89
C: 60-73
F: <50
How is this calculated?
Violations
44.4/45
A
Historical violation record including health-based and monitoring violations.
Lead & Copper
6/20
F
Lead at 17.0 ppb (90th percentile).
Contaminants
20/20
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 Northfield, IL water safe to drink?

Use Caution

Northfield's tap water meets most EPA standards but has areas that warrant attention. With a grade of B- (74.4/100), some contaminant levels or compliance issues suggest that residents may benefit from additional filtration. The city's 1 water system serves approximately 5,470 residents using surface water (rivers, lakes, or reservoirs).

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

Recent water quality updates for Northfield

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

Update
Water quality data updated

Latest EPA compliance and testing data incorporated into Northfield's water quality assessment. Grade: B- (74.4/100).

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

1 health-based. Contaminants: Lead and Copper Rule.

Key contaminant findings

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

Lead Exceeds Limit
Detected: 17.0 ppb Limit: 15 ppb (EPA Action Level)

Exceeds EPA action level. Lead service line replacement and point-of-use filtration recommended.

Violation history

Northfield's water system has 2 total violations on record, including 1 health-based violation. 2 remain unresolved.

TT
Most recent violations:
Dec 1992 Lead and Copper Rule Open

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 Des Plaines River, Mc Donald Creek, Weller Creek, Des Plaines R, North Branch 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 Northfield's water come from?

Northfield's drinking water comes from surface water (rivers, lakes, or reservoirs), supplied by 1 water system serving approximately 5,470 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), Mc Donald Creek (river), Weller Creek (river), Des Plaines R (river), North Branch Chicago River (river).

What Northfield residents can do

Install a water filter

Recommended: NSF 53-certified pitcher or under-sink filter. This addresses the specific contaminants found in Northfield'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

Northfield'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
Over Limit
17.0 ppb
EPA Action Level: 15 ppb · +13% over limit
Exceeds LimitFilter: NSF-53
PFAS Testing

Forever chemicals overview

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

Violation summary

2
Total violations
1
Health-based
2
Active / unresolved
Dec 1992
Most recent violation
Compliance Record

Violations & advisories

2 Total
2 Active
1 Health-based
0 Resolved
Dec 1992 Active
Lead and Copper Rule
Treatment Technique
Health-Based Health 0
Active
Compliance Violation
Monitoring 0
Industrial pollution

Top industrial polluters within 10 miles of Northfield

Industrial polluters nearby

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

Total reported releases to surface water: 3 lbs

FacilityTop chemicalTo surface water (lbs/yr)Distance
TRITON WEST LLC - SHELL DES PLAINES TERMINAL
Petroleum Bulk Terminals · SHELL PETROLEUM INC
ARLINGTON HEIGHTS, IL60005
Lead compounds210.0 mi
ACME ALLIANCE LLC
Primary Metals · ACME ALLIANCE LLC
NORTHBROOK, IL60062
Copper15.5 mi
VCNA PRAIRIE LLC. - YARD 1008
Nonmetallic Mineral Product · VCNA PRAIRIE LLC
DES PLAINES, IL60018
9.6 mi
RAHCO RUBBER INC.
Plastics and Rubber · NA
DES PLAINES, IL60018
8.1 mi
DELAVAL MANUFACTURING
Chemicals · DELAVAL INC
DES PLAINES, IL60018
9.4 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

Recommended water filters

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

🚰
For Lead
Reverse Osmosis or NSF 53-Certified Pitcher
Lead level (17.0 ppb) exceeds the EPA action level of 15 ppb
Read our guide →

Full contaminants report

Contaminant Detected Level EPA Limit Unit Category Status
Lead (90th percentile) 17.0 15 ppb Inorganic Over 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 23.6 ppb from 1992 (25.0 ppb) to 2025 (1.4 ppb).
Infrastructure

Water source & infrastructure

Primary Source
Purchased Surface Water
Operator
Local Government
Population Served
5,470
Water Systems
1
Water Source

Where Northfield's water comes from

Purchased Surface Water

Northfield'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 5,470 people through 1 water system.

Local Hydrology

Water bodies near Northfield

Northfield 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
Mc Donald Creek
river
Weller Creek
river
Des Plaines R
river
North Branch Chicago River
river
Infrastructure

Water systems serving Northfield

System Name PWSID Population Source
NORTHFIELD IL0312100 5,470 SWP
Regional Comparison

How Northfield compares

Full Illinois rankings →

Northfield's score of 74.4/100 is above the average of 56/100 among major Illinois cities. It outscores 7 of 10 nearby cities.

Northfield (this city)
74.4
Chicago
35.2
Aurora
45.5
Joliet
38.5
Naperville
81.2
Champaign
91.9
Illinois avg
56
City Profile

About Northfield, IL

Wikipedia →

Northfield is a village in Cook County, Illinois, United States, located approximately 19 miles (31 km) north of downtown Chicago. As of the 2020 census, the village's population was 5,751. It is part of a collection of upscale residential communities north of Chicago that belong to New Trier and Northfield Townships and the greater North Shore.

Economic Profile
$146,538
Median Income
$720,542
Median Home Value
$2,427/mo
Median Rent
1.5%
Unemployment
Community
49.9
Median Age
682
People / sq mi
76.9%
College Educated
91.8%
Homeownership
Share this reportHelp others learn about their water quality
WhatsAppXFacebookLinkedInEmail

Frequently asked questions

Is Northfield, IL tap water safe to drink?

Northfield's water quality earned a grade of B- (74.4/100). Some concerns have been identified. Consider a water filter for an extra layer of protection. The city ranks #685 out of 891 cities tested in Illinois.

What contaminants are in Northfield's water?

Lead was measured at 17.0 ppb (90th percentile). No PFAS compounds were detected. 2 violations are on record.

How is Northfield'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 Northfield?

Yes — lead levels exceed the EPA action level of 15 ppb. We recommend an NSF 53-certified filter or reverse osmosis system. Based on current data, basic filtration should suffice for additional peace of mind.

Where does Northfield's water come from?

Northfield's water is sourced from Purchased surface water. The city has 1 water system serving approximately 5,470 residents.

What health violations has Northfield's water system had?

Northfield has 1 health-based violation on record. The most recent violation was recorded in December 1992. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 2 violations remain unresolved.

How does Northfield's water compare to other cities?

Northfield ranks #685 out of 891 cities in Illinois (better than 23% of state cities) and #9853 out of 15744 cities nationally (37th percentile). The grade of B- reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.