TapSafetyReport
C53/100

MIDDLETON WATERWORKS — Water Quality Report 2026

Serving 23,868 people · Wisconsin

Water Source
Groundwater
County
—
System ID
WI1130242
Violations
32

Contaminant Test Results

1 contaminant above EPA health goals
ContaminantDetectedLimit (MCL)Status
Lead (90th percentile)
0.004 mg/L0.015 mg/LAbove Goal

EPA Violation History

30

Violations (last 5yr)

2

Unresolved

1

Health-Related

TIER 3Resolved

Reporting violation

This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.

When: October 17, 2024 – October 21, 2024Rule: Ground Water RuleEnforcement: Resolving — corrective action underway
TIER 2Resolved

Treatment technique violation

When: October 17, 2024 – May 29, 2025Rule: Ground Water RuleEnforcement: Resolving — corrective action underway
TIER 3Unresolved

Disinfection byproduct treatment technique failure

When: October 17, 2024Rule: Ground Water RuleVerify on EPA.gov
TIER 3Unresolved

Disinfection byproduct treatment technique failure

When: October 17, 2024Rule: Ground Water RuleVerify on EPA.gov
TIER 3Resolved

Exceeded the MCL for disinfection byproducts

This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.

When: January 1, 2023 – November 14, 2023Enforcement: Resolving — corrective action underway
TIER 3Resolved

Exceeded the MCL for disinfection byproducts

This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.

When: January 1, 2023 – November 14, 2023Enforcement: Resolving — corrective action underway
TIER 3Resolved

Exceeded the MCL for disinfection byproducts

This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.

When: January 1, 2023 – November 14, 2023Enforcement: Resolving — corrective action underway
TIER 3Resolved

Exceeded the MCL for disinfection byproducts

This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.

When: January 1, 2023 – November 14, 2023Enforcement: Resolving — corrective action underway
TIER 3Resolved

Exceeded the MCL for disinfection byproducts

This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.

When: January 1, 2023 – November 14, 2023Enforcement: Resolving — corrective action underway
TIER 3Resolved

Exceeded the MCL for disinfection byproducts

This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.

When: January 1, 2023 – November 14, 2023Enforcement: Resolving — corrective action underway
TIER 3Resolved

Exceeded the MCL for disinfection byproducts

This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.

When: January 1, 2023 – November 14, 2023Enforcement: Resolving — corrective action underway
TIER 3Resolved

Exceeded the MCL for disinfection byproducts

This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.

When: January 1, 2023 – November 14, 2023Enforcement: Resolving — corrective action underway
TIER 3Resolved

Exceeded the MCL for disinfection byproducts

This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.

When: January 1, 2023 – November 14, 2023Enforcement: Resolving — corrective action underway
TIER 3Resolved

Exceeded the MCL for disinfection byproducts

This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.

When: January 1, 2023 – November 14, 2023Enforcement: Resolving — corrective action underway
TIER 3Resolved

Exceeded the MCL for disinfection byproducts

This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.

When: January 1, 2023 – November 14, 2023Enforcement: Resolving — corrective action underway
TIER 3Resolved

Exceeded the MCL for disinfection byproducts

This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.

When: January 1, 2023 – November 14, 2023Enforcement: Resolving — corrective action underway
TIER 3Resolved

Exceeded the MCL for disinfection byproducts

This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.

When: January 1, 2023 – November 14, 2023Enforcement: Resolving — corrective action underway
TIER 3Resolved

Exceeded the MCL for disinfection byproducts

This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.

When: January 1, 2023 – November 14, 2023Enforcement: Resolving — corrective action underway
TIER 3Resolved

Exceeded the MCL for disinfection byproducts

This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.

When: January 1, 2023 – November 14, 2023Enforcement: Resolving — corrective action underway
TIER 3Resolved

Exceeded the MCL for disinfection byproducts

This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.

When: January 1, 2023 – November 14, 2023Enforcement: Resolving — corrective action underway
TIER 3Resolved

Exceeded the MCL for disinfection byproducts

This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.

When: January 1, 2023 – November 14, 2023Enforcement: Resolving — corrective action underway
TIER 3Resolved

Exceeded the MCL for disinfection byproducts

This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.

When: January 1, 2023 – November 14, 2023Enforcement: Resolving — corrective action underway
TIER 3Resolved

Exceeded the MCL for disinfection byproducts

This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.

When: January 1, 2023 – November 14, 2023Enforcement: Resolving — corrective action underway
TIER 3Resolved

Exceeded the MCL for disinfection byproducts

This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.

When: January 1, 2023 – November 14, 2023Enforcement: Resolving — corrective action underway
TIER 3Resolved

Exceeded the MCL for disinfection byproducts

This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.

When: January 1, 2023 – November 14, 2023Enforcement: Resolving — corrective action underway
TIER 3Resolved

Exceeded the MCL for disinfection byproducts

This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.

When: January 1, 2023 – November 14, 2023Enforcement: Resolving — corrective action underway
TIER 3Resolved

Exceeded the MCL for disinfection byproducts

This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.

When: January 1, 2023 – November 14, 2023Enforcement: Resolving — corrective action underway
TIER 3Resolved

Exceeded the MCL for disinfection byproducts

This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.

When: January 1, 2023 – November 14, 2023Enforcement: Resolving — corrective action underway
TIER 3Resolved

Exceeded the MCL for disinfection byproducts

This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.

When: January 1, 2023 – November 14, 2023Enforcement: Resolving — corrective action underway
TIER 3Resolved

Exceeded the MCL for disinfection byproducts

This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.

When: January 1, 2023 – November 14, 2023Enforcement: Resolving — corrective action underway

Understanding violation severity

Tier 1Urgent health risk. Utility must notify all customers within 24 hours.Tier 2Important health or treatment issue. Customers notified within 30 days.Tier 3Administrative or monitoring issue. Reported in the annual water quality report.

Source: EPA Safe Drinking Water Information System (SDWIS) · Updated quarterly

Frequently Asked Questions About MIDDLETON WATERWORKS

Is MIDDLETON WATERWORKS water safe to drink?

MIDDLETON WATERWORKS water receives a grade of C (53/100), which is considered fair. 0 contaminant(s) exceed EPA legal limits and 32 violation(s) are on record. Customers may want to consider using a water filter.

What contaminants has MIDDLETON WATERWORKS detected?

66 contaminants were tested in MIDDLETON WATERWORKS's water. Notable contaminants include Lead (90th percentile). No contaminants exceed EPA legal limits. 1 exceed EPA health goals (MCLGs).

Does MIDDLETON WATERWORKS have any EPA violations?

Yes, MIDDLETON WATERWORKS has 32 EPA violation(s) on record, with the most recent in 2024. Violation types include RPT, TT, Other. 3 are health-based violations.

How many people does MIDDLETON WATERWORKS serve?

MIDDLETON WATERWORKS serves approximately 23,868 people, Wisconsin. The system provides water to 1 community: Middleton.

What type of water does MIDDLETON WATERWORKS provide?

MIDDLETON WATERWORKS sources its water from groundwater. Groundwater is pumped from underground aquifers, which often provides natural filtration. The utility's system ID is WI1130242.

How does MIDDLETON WATERWORKS compare to other utilities in Wisconsin?

MIDDLETON WATERWORKS scores 53/100 with a grade of C (fair). This score indicates room for improvement compared to other utilities. Visit our Wisconsin state page for a full comparison of water systems.

Cities Served

Middleton