WaterVerge

Is Darlington, WI Tap Water Safe to Drink?

Graded A-, with 5 unresolved violations on record. See what was cited — and what it means for your tap. What to do next ↓

2K residents served 1 water system PWSID: WI1330073
Overall Score
85 / 100
Violations
5 active
Last Updated
May 2026
Source
Groundwater
#169 of 446 in Wisconsin Top 36% nationally
Local Government
Moderate data confidence
Reviewed by WaterVerge Editorial Team · Last updated May 2026
A-GRADE
Water Quality Grade
85/100
waterverge.com
A- 85/100

Darlington, WI — Water Quality Report

Darlington's drinking water received a grade of A- (85 out of 100), indicating good water quality. The city's 1 water system serves approximately 2,235 residents using groundwater.

Lead levels were measured at 1.0 ppb (90th percentile), well within EPA limits. This system has not yet been tested for PFAS under the EPA UCMR 5 program.

The system has 13 violations on record, including 5 health-based violations. 5 remain unresolved.

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

What to know about Darlington's water

Darlington ranks #169 out of 446 cities in Wisconsin for water quality, placing it mid-range in the state.

Darlington relies on groundwater, which is generally less vulnerable to surface contamination but can be affected by naturally occurring minerals like arsenic and nitrate, as well as agricultural and industrial runoff.

As a small community water system, Darlington may have fewer resources for advanced treatment technologies and infrastructure upgrades compared to larger utilities.

Quality Breakdown

Water quality score

See methodology →
85 out of 100 Grade A-
A: 90-100
B: 74-89
C: 60-73
F: <50
How is this calculated?
Violations
38/45
B
Historical violation record including health-based and monitoring violations.
Lead & Copper
20/20
A
Lead at 1.0 ppb (90th percentile).
Contaminants
17/20
B
PFAS + legacy contaminant analysis.
Compliance
5/10
D
Monitoring and reporting compliance with EPA regulations.
Source Risk
5/5
A
Water source: Groundwater.
Water Safety

Is Darlington, WI water safe to drink?

Concerns Identified

Darlington's drinking water has significant quality concerns based on EPA testing data. With a grade of A- (85/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 1 water system serves approximately 2,235 residents using groundwater (wells).

5
Active Violations
1.0 ppb
Lead (90th %ile)
3 events
Disaster History

Recent water quality updates for Darlington

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

Update
Water quality data updated

Latest EPA compliance and testing data incorporated into Darlington's water quality assessment. Grade: A- (85/100).

Violation
2 drinking water violations recorded

1 health-based. Contaminants: Public Notice, LEAD AND COPPER RULE REVISIONS.

Violation
1 drinking water violation recorded

1 health-based. Contaminants: Coliform (TCR).

Violation
2 drinking water violations recorded

Contaminants: Chlorine, Coliform (TCR).

Disaster
HURRICANE KATRINA EVACUATION

Federal disaster declaration (FEMA DR-3249). Hurricane event — may have impacted local water infrastructure.

Disaster
SEVERE STORMS, ICING, WIND & FLOODING

Federal disaster declaration (FEMA DR-496). Flood event — may have impacted local water infrastructure.

Key contaminant findings

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

Lead Within Limits
Detected: 1.0 ppb Limit: 15 ppb (EPA Action Level)

Well within EPA limits.

Violation history

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

OtherTTMCLMR
Most recent violations:
Oct 2024 Public Notice Open
Oct 2024 LEAD AND COPPER RULE REVISIONS Open
Aug 2014 Coliform (TCR) Resolved
Oct 2008 Chlorine Resolved
Oct 2008 Coliform (TCR) Resolved

Flood & environmental risk

Lafayette County has experienced 3 federally declared disasters since 1969. 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 Pecatonica River.

HURRICANE KATRINA EVACUATION
Hurricane FEMA DR-3249
SEVERE STORMS, ICING, WIND & FLOODING
Flood FEMA DR-496
SEVERE STORMS & FLOODING
Flood FEMA DR-264

Where does Darlington's water come from?

Darlington's drinking water comes from groundwater (wells), supplied by 1 water system serving approximately 2,235 people. Groundwater is generally less susceptible to surface contamination but can contain naturally occurring contaminants like arsenic, radon, and nitrate. Nearby water bodies include Pecatonica River (river).

What Darlington residents can do

Install a water filter

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

Darlington'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
1.0 ppb
EPA Action Level: 15 ppb · 7% of limit
Safe Level
Compliance Record

Violation summary

13
Total violations
5
Health-based
5
Active / unresolved
Oct 2024
Most recent violation
Compliance Record

Violations & advisories

13 Total
5 Active
5 Health-based
8 Resolved
Violations by category
Total Coliform Rule
5
Public Notice Rule and Revised PN Rule
2
Stage 1 Disinfectants and Disinfection Byproducts Rule
2
Lead and Copper Rule
2
Lead and Copper Rule Revisions
1
Oct 2024 Active
Public Notice
Other Violation 0
Oct 2024 Active
LEAD AND COPPER RULE REVISIONS
Treatment Technique
Health-Based Health 0
Jan 2006 Active
Lead and Copper Rule
Treatment Technique
Health-Based Health 0
Jan 2006 Active
Public Notice
Other Violation 0
Active
Compliance Violation
Monitoring 0
Aug 2014 Resolved
Coliform (TCR)
Max Contaminant Level
Health-Based Health Resolved Aug 2014
Oct 2008 Resolved
Chlorine
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2008
Oct 2008 Resolved
Coliform (TCR)
Monitoring & Reporting
Monitoring & Reporting Resolved Oct 2008
Aug 2008 Resolved
Coliform (TCR)
Monitoring & Reporting
Monitoring & Reporting Resolved Aug 2008
Jul 2008 Resolved
Chlorine
Monitoring & Reporting
Monitoring & Reporting Resolved Sep 2008
Jan 2005 Resolved
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2005
Oct 1994 Resolved
Coliform (TCR)
Max Contaminant Level
Health-Based Health Resolved Oct 1994
Oct 1991 Resolved
Coliform (TCR)
Max Contaminant Level
Health-Based Health Resolved Oct 1991
Industrial pollution

Top industrial polluters within 10 miles of Darlington

Industrial polluters nearby

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

FacilityTop chemicalTo surface water (lbs/yr)Distance
PRAIRIE FARMS WHITE HILL CHEESE
Food · PRAIRIE FARMS DAIRY INC
SHULLSBURG, WI53586
9.7 mi

Source: EPA Toxic Release Inventory (TRI) 2023

Environmental Risk

Flood & disaster history

3
Declared disasters
Sep 2005
Most recent
Flood
Most common type

Lafayette County has experienced 3 federally declared disasters since 1969. Flooding and severe weather can compromise water treatment infrastructure and introduce contaminants into drinking water supplies.

Sep 2005
HURRICANE KATRINA EVACUATION
Hurricane FEMA #3249
Mar 1976
SEVERE STORMS, ICING, WIND & FLOODING
Flood FEMA #496
Jul 1969
SEVERE STORMS & FLOODING
Flood FEMA #264

Full contaminants report

Contaminant Detected Level EPA Limit Unit Category Status
Lead (90th percentile) 1.0 15 ppb Inorganic Safe
Data source: EPA SDWIS, UCMR 5, local utility CCR.

Lead level trend (90th percentile)

EPA action level: 15 ppb
Lead has decreased by 11.0 ppb from 1993 (12.0 ppb) to 2023 (1.0 ppb).
Infrastructure

Water source & infrastructure

Primary Source
Groundwater
Operator
Local Government
Population Served
2,235
Water Systems
1
Water Source

Where Darlington's water comes from

Groundwater

Darlington's drinking water is drawn from underground aquifers through wells.

Groundwater is naturally filtered through rock and soil layers, generally requiring less treatment than surface water. However, it can contain naturally occurring contaminants like arsenic, radon, and minerals.

Agricultural activity, septic systems, and industrial operations near well fields can introduce nitrates, pesticides, and volatile organic compounds.

The system is operated by local government ownership and serves approximately 2,235 people through 1 water system.

Local Hydrology

Water bodies near Darlington

Darlington is located near 1 notable water body. These water bodies contribute to the regional watershed and may indirectly affect groundwater quality.

Pecatonica River
river
Infrastructure

Water systems serving Darlington

System Name PWSID Population Source
DARLINGTON WATERWORKS WI1330073 2,235 GW
Regional Comparison

How Darlington compares

Full Wisconsin rankings →

Darlington's score of 85/100 is above the average of 65/100 among major Wisconsin cities. It outscores 8 of 10 nearby cities.

Darlington (this city)
85
Milwaukee
90.2
Madison
35.4
Racine
69.5
Kenosha
45.8
Wisconsin avg
65
City Profile

About Darlington, WI

Economic Profile
$60,682
Median Income
$119,320
Median Home Value
$881/mo
Median Rent
1.9%
Unemployment
Community
42.1
Median Age
576
People / sq mi
18.2%
College Educated
67.8%
Homeownership
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Frequently asked questions

Is Darlington, WI tap water safe to drink?

Darlington's water quality earned a grade of A- (85/100). The water generally meets EPA standards and is considered safe for consumption. The city ranks #169 out of 446 cities tested in Wisconsin.

What contaminants are in Darlington's water?

Lead was measured at 1.0 ppb (90th percentile). 13 violations are on record.

How is Darlington'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 Darlington?

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

Where does Darlington's water come from?

Darlington's water is sourced from Groundwater. The city has 1 water system serving approximately 2,235 residents.

What health violations has Darlington's water system had?

Darlington has 5 health-based violations on record. The most recent violation was recorded in October 2024. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 5 violations remain unresolved.

Is Darlington's groundwater at risk of contamination?

Darlington uses groundwater, which can be affected by naturally occurring contaminants like arsenic, radon, and nitrate, as well as agricultural runoff and industrial activity. The system has 13 violations on record that may relate to groundwater quality. Groundwater systems are generally less susceptible to surface contamination but should be monitored for emerging contaminants like PFAS.

How does Darlington's water compare to other cities?

Darlington ranks #169 out of 446 cities in Wisconsin (better than 62% of state cities) and #5570 out of 15744 cities nationally (65th percentile). The grade of A- reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.

Does Darlington's small water system affect quality?

Darlington's system serves approximately 2,235 residents. Small community water systems (under 3,300 people) may have fewer financial resources for infrastructure upgrades and advanced treatment technologies. However, they are held to the same EPA drinking water standards as larger systems. This system has 13 violations on record.