WaterVerge

Is Beloit, WI Tap Water Safe to Drink?

Graded B+ — but 1,4-Dioxane and Manganese were detected above EPA limits. Here's what's in the water and how to remove it. What to do next ↓

37K residents served 1 water system PWSID: WI1540112
Overall Score
84 / 100
Violations
3 active
Last Updated
May 2026
Source
Groundwater
#188 of 446 in Wisconsin Top 39% nationally
Local Government
High data confidence
Reviewed by WaterVerge Editorial Team · Last updated May 2026
B+GRADE
Water Quality Grade
84/100
waterverge.com
B+ 84/100

Beloit, WI — Water Quality Report

Beloit's drinking water received a grade of B+ (84 out of 100), indicating good water quality. The city's 1 water system serves approximately 36,677 residents using groundwater.

Lead levels were measured at 4.5 ppb (90th percentile), well within EPA limits. UCMR 5 testing detected 1 PFAS compound in the water supply.

The system has 11 violations on record, including 2 health-based violations. 3 remain unresolved.

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

What to know about Beloit's water

Beloit ranks #188 out of 446 cities in Wisconsin for water quality, placing it mid-range in the state.

Beloit 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.

PFAS compounds were detected in testing, though levels remain within current EPA limits. Residents seeking extra precaution may consider an activated carbon or reverse osmosis filter.

Hexavalent chromium (chromium-6) was detected at 2.08 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 →
84 out of 100 Grade B+
A: 90-100
B: 74-89
C: 60-73
F: <50
How is this calculated?
Violations
42/45
A
Historical violation record including health-based and monitoring violations.
Lead & Copper
18/20
A
Lead at 4.5 ppb (90th percentile).
Contaminants
14/20
C
1 PFAS compound detected.
Compliance
5/10
D
Monitoring and reporting compliance with EPA regulations.
Source Risk
5/5
A
Water source: Groundwater.
Water Safety

Is Beloit, WI water safe to drink?

Concerns Identified

Beloit's drinking water has significant quality concerns based on EPA testing data. With a grade of B+ (84/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 1 water system serves approximately 36,677 residents using groundwater (wells).

3
Active Violations
4.5 ppb
Lead (90th %ile)
1 compound
PFAS Detected
3 events
Disaster History

Recent water quality updates for Beloit

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

PFAS
1 PFAS "forever chemical" compound detected

Detected at levels within current EPA limits. PFAS persist indefinitely in the environment.

Update
Water quality data updated

Latest EPA compliance and testing data incorporated into Beloit's water quality assessment. Grade: B+ (84/100).

Violation
1 drinking water violation recorded

Contaminants: Consumer Confidence Rule.

Violation
1 drinking water violation recorded

1 health-based. Contaminants: Combined Radium (-226 and -228).

Violation
1 drinking water violation recorded

1 health-based. Contaminants: Combined Radium (-226 and -228).

Disaster
HURRICANE KATRINA EVACUATION

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

Key contaminant findings

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

Lead Within Limits
Detected: 4.5 ppb Limit: 15 ppb (EPA Action Level)

Well within EPA limits.

PFAS (1 compound) Elevated
Detected: Highest: PFBS at 0.0030 µg/L Limit: 0.004 µg/L (EPA MCL)

Detected but within current EPA limits. PFAS do not break down in the environment and can accumulate in the body over time. An activated carbon filter can reduce exposure.

Violation history

Beloit's water system has 11 total violations on record, including 2 health-based violations. 3 remain unresolved. 1 violation was issued in the last 5 years.

OtherMCLMR
Most recent violations:
Jul 2024 Consumer Confidence Rule Open
Oct 2019 Combined Radium (-226 and -228) Resolved
Jul 2019 Combined Radium (-226 and -228) Resolved
Jul 2013 Consumer Confidence Rule Open
Apr 2006 Nitrate Resolved

Flood & environmental risk

Rock County has experienced 3 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 Rock River, Pecatonica River Nr Shirland, Ill.

HURRICANE KATRINA EVACUATION
Hurricane FEMA DR-3249
SEVERE STORMS, ICING, WIND & FLOODING
Flood FEMA DR-496
SEVERE STORMS & FLOODING
Flood FEMA DR-376

Where does Beloit's water come from?

Beloit's drinking water comes from groundwater (wells), supplied by 1 water system serving approximately 36,677 people. Groundwater is generally less susceptible to surface contamination but can contain naturally occurring contaminants like arsenic, radon, and nitrate. Nearby water bodies include Rock River (river), Pecatonica River Nr Shirland, Ill (river).

What Beloit residents can do

Install a water filter

Recommended: Activated carbon or reverse osmosis filter. This addresses the specific contaminants found in Beloit'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

Beloit'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
4.5 ppb
EPA Action Level: 15 ppb · 30% of limit
Safe Level
PFBS
PFAS / Forever Chemical
Near MCL
0.0030 µg/L
EPA MCL: 0.004 µg/L · 75% of limit
Detected
HAA5 (Disinfection Byproducts)
Disinfection Byproduct
Safe
1.1 µg/L
EPA MCL: 60 µg/L · 2% of limit
Within LimitUCMR 4 DataHAA6Br: 3.6 µg/LHAA9: 4.0 µg/L
Chromium-6 (Hexavalent Chromium)
Inorganic
Detected
2.08 µg/L
CA MCL (no federal MCL): 10 µg/L · 21% of limit
DetectedUCMR 3 Data
Strontium
Inorganic
Detected
123.1 µg/L
EPA Health Ref Level: 1,500 µg/L · 8% of limit
DetectedUCMR 3 Data
1,4-Dioxane
Organic
Over HA
0.68 µg/L
EPA Health Advisory: 0.35 µg/L · +20% over limit
Over Health AdvisoryUCMR 3 Data
Manganese
Inorganic
Over SMCL
112.0 µg/L
EPA Secondary MCL: 50 µg/L · +20% over limit
Over SMCLUCMR 4 Data
Vanadium
Inorganic
Detected
0.99 µg/L
EPA Short-term HA: 21 µg/L · 5% of limit
DetectedUCMR 3 Data
Molybdenum
Inorganic
Detected
3.53 µg/L
EPA Lifetime HA: 40 µg/L · 9% of limit
DetectedUCMR 3 Data
PFAS Testing

Forever chemicals overview

National PFAS report →
30
Compounds tested
1
Detected
0
Exceed EPA MCL
Compliance Record

Violation summary

11
Total violations
2
Health-based
3
Active / unresolved
Jul 2024
Most recent violation
Compliance Record

Violations & advisories

11 Total
3 Active
2 Health-based
8 Resolved
Violations by category
Nitrate Rule
4
Consumer Confidence Rule
2
Radionuclides and Revised Rad Rule
2
Lead and Copper Rule
1
Total Coliform Rule
1
Jul 2024 Active
Consumer Confidence Rule
Other Violation 0
Jul 2013 Active
Consumer Confidence Rule
Other Violation 0
Active
Compliance Violation
Monitoring 0
Oct 2019 Resolved
Combined Radium (-226 and -228)
Max Contaminant Level
Health-Based Health Resolved Dec 2019
Jul 2019 Resolved
Combined Radium (-226 and -228)
Max Contaminant Level
Health-Based Health Resolved Sep 2019
Apr 2006 Resolved
Nitrate
Monitoring & Reporting
Monitoring & Reporting Resolved Jun 2006
Apr 2004 Resolved
Nitrate
Monitoring & Reporting
Monitoring & Reporting Resolved Jun 2004
Apr 2004 Resolved
Nitrate
Monitoring & Reporting
Monitoring & Reporting Resolved Jun 2004
Jan 1995 Resolved
Nitrate
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 1995
Jan 1993 Resolved
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting Resolved Jul 1993
Feb 1991 Resolved
Coliform (TCR)
Monitoring & Reporting
Monitoring & Reporting Resolved Feb 1991
Industrial pollution

Top industrial polluters within 10 miles of Beloit

Industrial polluters nearby

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

FacilityTop chemicalTo surface water (lbs/yr)Distance
FRITO-LAY INC
Food · PEPSICO INC
BELOIT, WI53511
1.7 mi
HORMEL FOODS CORP
Food · HORMEL FOODS CORP
BELOIT, WI53511
1.9 mi
GENENCOR INTERNATIONAL WISCONSIN INC.
Chemicals · INTERNATIONAL FLAVORS & FRAGRANCES INC
BELOIT, WI53511
1.5 mi
STAINLESS TANK & EQUIPMENT CO LLC
Transportation Equipment · HENDRICKS HOLDING CO INC
BELOIT, WI53511
1.6 mi
NORTHSTAR MEDICAL RADIOISOTOPES LLC
Chemicals · NA
BELOIT, WI53511
3.0 mi

Source: EPA Toxic Release Inventory (TRI) 2023

Site context

Superfund sites within 10 miles of Beloit

Superfund sites nearby

Federally tracked hazardous-waste sites on the EPA National Priorities List. Proximity does not necessarily indicate tap-water contamination — the connection depends on hydrology and treatment.

Source: EPA Superfund National Priorities List

Environmental Risk

Flood & disaster history

3
Declared disasters
Sep 2005
Most recent
Flood
Most common type

Rock County has experienced 3 federally declared disasters since 1973. 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
Apr 1973
SEVERE STORMS & FLOODING
Flood FEMA #376

Recommended water filters

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

🧪
For PFAS
Reverse Osmosis or Activated Carbon Block
1 PFAS compound detected

Full contaminants report

Contaminant Detected Level EPA Limit Unit Category Status
Lead (90th percentile) 4.5 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 0.003 HI µg/L PFAS 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 3.5 ppb from 1992 (8.0 ppb) to 2023 (4.5 ppb).
Infrastructure

Water source & infrastructure

Primary Source
Groundwater
Operator
Local Government
Population Served
36,677
Water Systems
1
Water Source

Where Beloit's water comes from

Groundwater

Beloit'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 36,677 people through 1 water system.

Local Hydrology

Water bodies near Beloit

Beloit is located near 2 notable water bodies. These water bodies contribute to the regional watershed and may indirectly affect groundwater quality.

Rock River
river
Pecatonica River Nr Shirland, Ill
river
Infrastructure

Water systems serving Beloit

System Name PWSID Population Source
BELOIT CITY OF WI1540112 36,677 GW
Regional Comparison

How Beloit compares

Full Wisconsin rankings →

Beloit's score of 84/100 is above the average of 65/100 among major Wisconsin cities. It outscores 8 of 10 nearby cities.

Beloit (this city)
84
Milwaukee
90.2
Madison
35.4
Racine
69.5
Kenosha
45.8
Wisconsin avg
65
City Profile

About Beloit, WI

Wikipedia →

Beloit is a city in Rock County, Wisconsin, United States. It is located along the Rock River in southern Wisconsin, on the state border with Illinois. The population was 36,657 at the 2020 census. The Janesville–Beloit metropolitan statistical area, consisting solely of Rock County, has an estimated 165,000 residents.

Economic Profile
$57,168
Median Income
$122,031
Median Home Value
$957/mo
Median Rent
6%
Unemployment
Community
33.9
Median Age
816
People / sq mi
18.1%
College Educated
59.3%
Homeownership
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Frequently asked questions

Is Beloit, WI tap water safe to drink?

Beloit's water quality earned a grade of B+ (84/100). The water generally meets EPA standards and is considered safe for consumption. The city ranks #188 out of 446 cities tested in Wisconsin.

What contaminants are in Beloit's water?

Lead was measured at 4.5 ppb (90th percentile). 1 PFAS compound was detected. 11 violations are on record.

How is Beloit'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 Beloit?

PFAS compounds have been detected. A filter with activated carbon can help reduce exposure.

Where does Beloit's water come from?

Beloit's water is sourced from Groundwater. The city has 1 water system serving approximately 36,677 residents.

What health violations has Beloit's water system had?

Beloit has 2 health-based violations on record. The most recent violation was recorded in July 2024. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 3 violations remain unresolved.

Is Beloit's groundwater at risk of contamination?

Beloit 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 11 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 Beloit's water compare to other cities?

Beloit ranks #188 out of 446 cities in Wisconsin (better than 58% of state cities) and #6114 out of 15744 cities nationally (61th percentile). The grade of B+ reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.