WaterVerge

Is Shell Lake, WI Tap Water Safe to Drink?

Graded B+, with 7 unresolved violations on record. See what was cited — and what it means for your tap. What to do next ↓

950 residents served 1 water system PWSID: WI8660304
Overall Score
80.3 / 100
Violations
7 active
Last Updated
May 2026
Source
Groundwater
#258 of 446 in Wisconsin Top 51% nationally
Local Government
Moderate data confidence
Reviewed by WaterVerge Editorial Team · Last updated May 2026
B+GRADE
Water Quality Grade
80.3/100
waterverge.com
B+ 80.3/100

Shell Lake, WI — Water Quality Report

Shell Lake's drinking water received a grade of B+ (80.3 out of 100), indicating good water quality. The city's 1 water system serves approximately 950 residents using groundwater.

Lead levels were measured at 1.3 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 25 violations on record, including 14 health-based violations. 7 remain unresolved.

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

What to know about Shell Lake's water

Shell Lake ranks #258 out of 446 cities in Wisconsin for water quality, placing it below average in the state.

Shell Lake 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, Shell Lake may have fewer resources for advanced treatment technologies and infrastructure upgrades compared to larger utilities.

Quality Breakdown

Water quality score

See methodology →
80.3 out of 100 Grade B+
A: 90-100
B: 74-89
C: 60-73
F: <50
How is this calculated?
Violations
33.3/45
B
Historical violation record including health-based and monitoring violations.
Lead & Copper
20/20
A
Lead at 1.3 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 Shell Lake, WI water safe to drink?

Concerns Identified

Shell Lake's drinking water has significant quality concerns based on EPA testing data. With a grade of B+ (80.3/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 1 water system serves approximately 950 residents using groundwater (wells).

7
Active Violations
1.3 ppb
Lead (90th %ile)
2 events
Disaster History

Recent water quality updates for Shell Lake

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

Update
Water quality data updated

Latest EPA compliance and testing data incorporated into Shell Lake's water quality assessment. Grade: B+ (80.3/100).

Violation
1 drinking water violation recorded

Contaminants: LEAD AND COPPER RULE REVISIONS.

Violation
2 drinking water violations recorded

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

Violation
1 drinking water violation recorded

Contaminants: Lead and Copper Rule.

Disaster
HURRICANE KATRINA EVACUATION

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

Disaster
FLOODING, SEVERE STORMS AND TORNADOES

Federal disaster declaration (FEMA DR-1369). Flood event — may have impacted local water infrastructure.

Key contaminant findings

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

Lead Within Limits
Detected: 1.3 ppb Limit: 15 ppb (EPA Action Level)

Well within EPA limits.

Violation history

Shell Lake's water system has 25 total violations on record, including 14 health-based violations. 7 remain unresolved. 4 violations were issued in the last 5 years.

RPTOtherTTMRMCL
Most recent violations:
Jul 2025 LEAD AND COPPER RULE REVISIONS Open
Oct 2024 Public Notice Open
Oct 2024 LEAD AND COPPER RULE REVISIONS Open
Jan 2024 Lead and Copper Rule Open
Oct 2014 Coliform (TCR) Resolved

Flood & environmental risk

Washburn County has experienced 2 federally declared disasters since 2001. Flooding and severe storms can overwhelm water treatment plants, cause sewage overflows, and introduce agricultural runoff, bacteria, and sediment into drinking water supplies.

HURRICANE KATRINA EVACUATION
Hurricane FEMA DR-3249
FLOODING, SEVERE STORMS AND TORNADOES
Flood FEMA DR-1369

Where does Shell Lake's water come from?

Shell Lake's drinking water comes from groundwater (wells), supplied by 1 water system serving approximately 950 people. Groundwater is generally less susceptible to surface contamination but can contain naturally occurring contaminants like arsenic, radon, and nitrate.

What Shell Lake residents can do

Install a water filter

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

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
1.3 ppb
EPA Action Level: 15 ppb · 9% of limit
Safe Level
Compliance Record

Violation summary

25
Total violations
14
Health-based
7
Active / unresolved
Jul 2025
Most recent violation
Compliance Record

Violations & advisories

25 Total
7 Active
14 Health-based
18 Resolved
Violations by category
Total Coliform Rule
18
Lead and Copper Rule Revisions
2
Public Notice Rule and Revised PN Rule
2
Lead and Copper Rule
1
Consumer Confidence Rule
1
Jul 2025 Active
LEAD AND COPPER RULE REVISIONS
Reporting
Reporting 0
Oct 2024 Active
Public Notice
Other Violation 0
Oct 2024 Active
LEAD AND COPPER RULE REVISIONS
Treatment Technique
Health-Based Health 0
Jan 2024 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
Oct 2009 Active
Public Notice
Other Violation 0
Jul 2002 Active
Consumer Confidence Rule
Other Violation 0
Active
Compliance Violation
Monitoring 0
Oct 2014 Resolved
Coliform (TCR)
Max Contaminant Level
Health-Based Health Resolved Oct 2014
Aug 2014 Resolved
Coliform (TCR)
Max Contaminant Level
Health-Based Health Resolved Aug 2014
Nov 2012 Resolved
Coliform (TCR)
Max Contaminant Level
Health-Based Health Resolved Nov 2012
Sep 2009 Resolved
Coliform (TCR)
Monitoring & Reporting
Monitoring & Reporting Resolved Sep 2009
Nov 2008 Resolved
Coliform (TCR)
Max Contaminant Level
Health-Based Health Resolved Nov 2008
Nov 2002 Resolved
Coliform (TCR)
Monitoring & Reporting
Monitoring & Reporting Resolved Nov 2002
Oct 2002 Resolved
Coliform (TCR)
Monitoring & Reporting
Monitoring & Reporting Resolved Oct 2002
Sep 2002 Resolved
Coliform (TCR)
Max Contaminant Level
Health-Based Health Resolved Sep 2002
Feb 2001 Resolved
Coliform (TCR)
Max Contaminant Level
Health-Based Health Resolved Feb 2001
Jan 2001 Resolved
Coliform (TCR)
Max Contaminant Level
Health-Based Health Resolved Jan 2001
Nov 2000 Resolved
Coliform (TCR)
Max Contaminant Level
Health-Based Health Resolved Nov 2000
Sep 2000 Resolved
Coliform (TCR)
Max Contaminant Level
Health-Based Health Resolved Sep 2000
Nov 1999 Resolved
Coliform (TCR)
Monitoring & Reporting
Monitoring & Reporting Resolved Nov 1999
Showing 20 of 25 violations
Industrial pollution

Top industrial polluters within 10 miles of Shell Lake

Industrial polluters nearby

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

FacilityTop chemicalTo surface water (lbs/yr)Distance
LEJEUNE STEEL CO. (2950 BARRONETT)
Fabricated Metals · API GROUP INC
BARRONETT, WI54813
7.6 mi

Source: EPA Toxic Release Inventory (TRI) 2023

Environmental Risk

Flood & disaster history

2
Declared disasters
Sep 2005
Most recent
Hurricane
Most common type

Washburn County has experienced 2 federally declared disasters since 2001. Flooding and severe weather can compromise water treatment infrastructure and introduce contaminants into drinking water supplies.

Sep 2005
HURRICANE KATRINA EVACUATION
Hurricane FEMA #3249
May 2001
FLOODING, SEVERE STORMS AND TORNADOES
Flood FEMA #1369

Full contaminants report

Contaminant Detected Level EPA Limit Unit Category Status
Lead (90th percentile) 1.3 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 0.5 ppb from 1993 (1.8 ppb) to 2023 (1.3 ppb).
Infrastructure

Water source & infrastructure

Primary Source
Groundwater
Operator
Local Government
Population Served
950
Water Systems
1
Water Source

Where Shell Lake's water comes from

Groundwater

Shell Lake'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 950 people through 1 water system.

Infrastructure

Water systems serving Shell Lake

System Name PWSID Population Source
SHELL LAKE WATERWORKS WI8660304 950 GW
Regional Comparison

How Shell Lake compares

Full Wisconsin rankings →

Shell Lake's score of 80.3/100 is above the average of 65/100 among major Wisconsin cities. It outscores 7 of 10 nearby cities.

Shell Lake (this city)
80.3
Milwaukee
90.2
Madison
35.4
Racine
69.5
Kenosha
45.8
Wisconsin avg
65
City Profile

About Shell Lake, WI

Wikipedia →

Shell Lake is a city in Washburn County, Wisconsin, United States. The population was 1,371 at the 2020 census. It is the county seat of Washburn County.

Economic Profile
$52,500
Median Income
$185,173
Median Home Value
$816/mo
Median Rent
3.3%
Unemployment
Community
42.8
Median Age
110
People / sq mi
26.3%
College Educated
71.7%
Homeownership
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Frequently asked questions

Is Shell Lake, WI tap water safe to drink?

Shell Lake's water quality earned a grade of B+ (80.3/100). The water generally meets EPA standards and is considered safe for consumption. The city ranks #258 out of 446 cities tested in Wisconsin.

What contaminants are in Shell Lake's water?

Lead was measured at 1.3 ppb (90th percentile). 25 violations are on record.

How is Shell Lake'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 Shell Lake?

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

Where does Shell Lake's water come from?

Shell Lake's water is sourced from Groundwater. The city has 1 water system serving approximately 950 residents.

What health violations has Shell Lake's water system had?

Shell Lake has 14 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. 7 violations remain unresolved.

Is Shell Lake's groundwater at risk of contamination?

Shell Lake 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 25 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 Shell Lake's water compare to other cities?

Shell Lake ranks #258 out of 446 cities in Wisconsin (better than 42% of state cities) and #7932 out of 15744 cities nationally (50th percentile). The grade of B+ reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.

Does Shell Lake's small water system affect quality?

Shell Lake's system serves approximately 950 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 25 violations on record.