B65/100

SUN PRAIRIE UTILITIES — Water Quality Report 2026

Serving 33,966 people · Wisconsin

Water Source
Groundwater
County
System ID
WI1130258
Violations
24

Contaminant Test Results

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

EPA Violation History

2

Violations (last 5yr)

0

Unresolved

1

Health-Related

TIER 2Resolved

Exceeded the Maximum Contaminant Level (running average)

When: January 1, 2023 – March 31, 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: July 1, 2021 – September 30, 2021Enforcement: 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 SUN PRAIRIE UTILITIES

Is SUN PRAIRIE UTILITIES water safe to drink?

SUN PRAIRIE UTILITIES water receives a grade of B (65/100), which is considered good. Out of 66 contaminants tested, none exceed EPA legal limits. 1 contaminant(s) exceed non-enforceable health goals. The water meets federal safety standards.

What contaminants has SUN PRAIRIE UTILITIES detected?

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

Does SUN PRAIRIE UTILITIES have any EPA violations?

Yes, SUN PRAIRIE UTILITIES has 24 EPA violation(s) on record, with the most recent in 2023. Violation types include MCL, MR. 2 are health-based violations.

How many people does SUN PRAIRIE UTILITIES serve?

SUN PRAIRIE UTILITIES serves approximately 33,966 people, Wisconsin. The system provides water to 1 community: Sun Prairie.

What type of water does SUN PRAIRIE UTILITIES provide?

SUN PRAIRIE UTILITIES sources its water from groundwater. Groundwater is pumped from underground aquifers, which often provides natural filtration. The utility's system ID is WI1130258.

How does SUN PRAIRIE UTILITIES compare to other utilities in Wisconsin?

SUN PRAIRIE UTILITIES scores 65/100 with a grade of B (good). This is an above-average performance for utilities statewide. Visit our Wisconsin state page for a full comparison of water systems.

Cities Served