WaterVerge

Is Plymouth, WI Tap Water Safe to Drink?

Graded C+ — but Lead and Copper were detected above EPA limits. Here's what's in the water and how to remove it. What to do next ↓

12K residents served 4 water systems PWSID: WI4600446
Overall Score
69.5 / 100
Violations
16 active
Last Updated
May 2026
Source
Groundwater
#353 of 446 in Wisconsin Top 69% nationally
Local Government
High data confidence
Reviewed by WaterVerge Editorial Team · Last updated May 2026
C+GRADE
Water Quality Grade
69.5/100
waterverge.com
C+ 69.5/100

Plymouth, WI — Water Quality Report

Plymouth's drinking water received a grade of C+ (69.5 out of 100), indicating fair water quality. The city's 4 water systems serve approximately 12,272 residents using groundwater.

Lead levels were measured at 21.8 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 94 violations on record, including 8 health-based violations. 16 remain unresolved.

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

What to know about Plymouth's water

Plymouth ranks #353 out of 446 cities in Wisconsin for water quality, placing it among the lowest-rated in the state.

Plymouth 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.

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 →
69.5 out of 100 Grade C+
A: 90-100
B: 74-89
C: 60-73
F: <50
How is this calculated?
Violations
37/45
B
Historical violation record including health-based and monitoring violations.
Lead & Copper
2/20
F
Lead at 21.8 ppb (90th percentile).
Contaminants
17.5/20
B
No PFAS compounds detected.
Compliance
8/10
B
Monitoring and reporting compliance with EPA regulations.
Source Risk
5/5
A
Water source: Groundwater.
Water Safety

Is Plymouth, WI water safe to drink?

Concerns Identified

Plymouth's drinking water has significant quality concerns based on EPA testing data. With a grade of C+ (69.5/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 4 water systems serve approximately 12,272 residents using groundwater (wells).

16
Active Violations
21.8 ppb
Lead (90th %ile)
None
PFAS Detected
4 events
Disaster History

Recent water quality updates for Plymouth

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

Update
Water quality data updated

Latest EPA compliance and testing data incorporated into Plymouth's water quality assessment. Grade: C+ (69.5/100).

Violation
1 drinking water violation recorded

Contaminants: Nitrate.

Violation
1 drinking water violation recorded

Contaminants: Chlorine.

Violation
21 drinking water violations recorded

Contaminants: Benzene, Ethylbenzene, Vinyl chloride.

Disaster
HURRICANE KATRINA EVACUATION

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

Disaster
SEVERE STORMS & FLOODING

Federal disaster declaration (FEMA DR-775). Flood event — may have impacted local water infrastructure.

Key contaminant findings

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

Lead Exceeds Limit
Detected: 21.8 ppb Limit: 15 ppb (EPA Action Level)

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

Copper Exceeds Limit
Detected: 2.05 mg/L Limit: 1.3 mg/L (EPA Action Level)

Exceeds EPA action level. Copper can leach from household plumbing — flush taps for 30 seconds before drinking.

Violation history

Plymouth's water system has 94 total violations on record, including 8 health-based violations. 16 remain unresolved. 1 violation was issued in the last 5 years.

MRTTMCLOther
Most recent violations:
Apr 2024 Nitrate Resolved
Jul 2020 Chlorine Resolved
Apr 2015 Benzene Resolved
Apr 2015 Ethylbenzene Resolved
Apr 2015 Vinyl chloride Resolved

Flood & environmental risk

Sheboygan County has experienced 4 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.

HURRICANE KATRINA EVACUATION
Hurricane FEMA DR-3249
SEVERE STORMS & FLOODING
Flood FEMA DR-775
SEVERE STORMS, ICING, WIND & FLOODING
Flood FEMA DR-496

Where does Plymouth's water come from?

Plymouth's drinking water comes from groundwater (wells), supplied by 4 water systems serving approximately 12,272 people. Groundwater is generally less susceptible to surface contamination but can contain naturally occurring contaminants like arsenic, radon, and nitrate.

What Plymouth residents can do

Install a water filter

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

Plymouth'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
21.8 ppb
EPA Action Level: 15 ppb · +20% over limit
Exceeds LimitFilter: NSF-53
Copper (90th percentile)
Inorganic
Over Limit
2.05 mg/L
EPA Action Level: 1.3 mg/L · +20% over limit
Exceeds Limit
PFAS Testing

Forever chemicals overview

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

Violation summary

94
Total violations
8
Health-based
16
Active / unresolved
Apr 2024
Most recent violation
Compliance Record

Violations & advisories

94 Total
16 Active
8 Health-based
78 Resolved
Violations by category
Volatile Organic Chemicals
42
Lead and Copper Rule
13
Total Coliform Rule
13
Radionuclides and Revised Rad Rule
8
Nitrate Rule
7
Oct 2012 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
Jan 2012 Active
Lead and Copper Rule
Treatment Technique
Health-Based Health 0
Apr 2009 Active
Public Notice
Other Violation 0
Apr 2009 Active
Public Notice
Other Violation 0
Jul 2002 Active
Consumer Confidence Rule
Other Violation 0
Jan 2000 Active
Consumer Confidence Rule
Other Violation 0
Jan 2000 Active
Lead and Copper Rule
Treatment Technique
Health-Based Health 0
Oct 1999 Active
Consumer Confidence Rule
Other Violation 0
Jan 1994 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
Jan 1994 Active
Lead and Copper Rule
Treatment Technique
Health-Based Health 0
Jul 1993 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
Jan 1993 Active
Lead and Copper Rule
Treatment Technique
Health-Based Health 0
Jul 1992 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
Active
Compliance Violation
Monitoring 0
Active
Compliance Violation
Monitoring 0
Active
Compliance Violation
Monitoring 0
Apr 2024 Resolved
Nitrate
Monitoring & Reporting
Monitoring & Reporting Resolved Jun 2024
Jul 2020 Resolved
Chlorine
Monitoring & Reporting
Monitoring & Reporting Resolved Sep 2020
Apr 2015 Resolved
Benzene
Monitoring & Reporting
Monitoring & Reporting Resolved Jun 2015
Apr 2015 Resolved
Ethylbenzene
Monitoring & Reporting
Monitoring & Reporting Resolved Jun 2015
Showing 20 of 94 violations
Industrial pollution

Top industrial polluters within 10 miles of Plymouth

Industrial polluters nearby

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

Total reported releases to surface water: 1,803 lbs

FacilityTop chemicalTo surface water (lbs/yr)Distance
ACTUS NUTRITION-ADELL
Food · MILK SPECIALTIES GLOBAL
ADELL, WI53001
Nitrate compounds (water dissociable; reportable only when in aqueous solution)1,7498.7 mi
KOHLER CO
Fabricated Metals · KOHLER CO
KOHLER, WI530441500
Manganese549.3 mi
MILLENNIUM TECHNOLOGIES LLC
Fabricated Metals · NA
PLYMOUTH, WI53073
1.5 mi
SARTORI CO
Food · SARTORI CO
PLYMOUTH, WI53073
0.8 mi
DIAMOND VOGEL INC.
Chemicals · DIAMOND VOGEL INC
SHEBOYGAN FALLS, WI53085
7.7 mi

Source: EPA Toxic Release Inventory (TRI) 2023

Environmental Risk

Flood & disaster history

4
Declared disasters
Sep 2005
Most recent
Flood
Most common type

Sheboygan County has experienced 4 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
Oct 1986
SEVERE STORMS & FLOODING
Flood FEMA #775
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 Plymouth's water supply, we recommend the following filter types.

🚰
For Lead
Reverse Osmosis or NSF 53-Certified Pitcher
Lead level (21.8 ppb) exceeds the EPA action level of 15 ppb
Read our guide →
🔧
For Copper
Reverse Osmosis or KDF Filter
Copper exceeds the EPA action level of 1.3 mg/L

Full contaminants report

Contaminant Detected Level EPA Limit Unit Category Status
Lead (90th percentile) 21.8 15 ppb Inorganic Over Limit
Copper (90th percentile) 2.05 1.3 mg/L 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 12.2 ppb from 1992 (34.0 ppb) to 2025 (21.8 ppb).

Copper level trend (90th percentile)

EPA action level: 1.3 mg/L
Copper has decreased by 0.700 mg/L from 1992 (2.750 mg/L) to 1999 (2.050 mg/L).
Infrastructure

Water source & infrastructure

Primary Source
Groundwater
Operator
Local Government
Population Served
12,272
Water Systems
4
Water Source

Where Plymouth's water comes from

Groundwater

Plymouth'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 12,272 people through 4 water systems.

Infrastructure

Water systems serving Plymouth

System Name PWSID Population Source
PLYMOUTH UTILITIES WI4600446 8,964 GW
KETTLE MORAINE CORRECTIONAL INSTITUTION WI4600449 1,544 GW
LAKELAND UNIVERSITY WI4600487 1,200 GW
ROCKY KNOLL HEALTH CARE FAC WI4600447 564 GW
Regional Comparison

How Plymouth compares

Full Wisconsin rankings →

Plymouth's score of 69.5/100 is on par with the average of 65/100 among major Wisconsin cities. It outscores 5 of 10 nearby cities.

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

About Plymouth, WI

Wikipedia →

Plymouth is a city in Sheboygan County, Wisconsin, United States, along the Mullet River. The population was 8,932 at the 2020 census. It is included in the Sheboygan, Wisconsin, metropolitan area. The city is located in the Town of Plymouth, but it is politically independent. Plymouth was known as "Hub City" for its former role as a center of wooden wheelwrighting. It advertises itself as "The Cheese Capital of the World," as it produces 14% of all the cheese consumed in the United States. The Mayor is Don Pohlman.

Economic Profile
$65,893
Median Income
$179,294
Median Home Value
$848/mo
Median Rent
5.1%
Unemployment
Community
44.1
Median Age
642
People / sq mi
22.9%
College Educated
66.2%
Homeownership
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Frequently asked questions

Is Plymouth, WI tap water safe to drink?

Plymouth's water quality earned a grade of C+ (69.5/100). Some concerns have been identified. Consider a water filter for an extra layer of protection. The city ranks #353 out of 446 cities tested in Wisconsin.

What contaminants are in Plymouth's water?

Lead was measured at 21.8 ppb (90th percentile). No PFAS compounds were detected. 94 violations are on record.

How is Plymouth'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 Plymouth?

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 Plymouth's water come from?

Plymouth's water is sourced from Groundwater. The city has 4 water systems serving approximately 12,272 residents.

What health violations has Plymouth's water system had?

Plymouth has 8 health-based violations on record. The most recent violation was recorded in April 2024. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 16 violations remain unresolved.

Is Plymouth's groundwater at risk of contamination?

Plymouth 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 94 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 Plymouth's water compare to other cities?

Plymouth ranks #353 out of 446 cities in Wisconsin (better than 21% of state cities) and #10903 out of 15744 cities nationally (31th percentile). The grade of C+ reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.