State Hub
Wisconsin Water Quality
493
Utilities in database
4.1M
Residents served
38%
On private wells
3
Key contaminants tracked
Drinking Water in Wisconsin
Wisconsin has 493 community water systems serving approximately 4.1 million residents. Primary water sources include groundwater. The most commonly reported contaminants include arsenic, lead, disinfection byproducts. 38% of Wisconsin residents rely on private wells. DNR holds primary enforcement authority under the Safe Drinking Water Act.
Utilities in Wisconsin
451–475 of 493Camp Douglas Waterworks
WI7290121 · 640 served
Eleva Waterworks
WI6620270 · 635 served
Brownsville Waterworks
WI1140139 · 630 served
Bruce Waterworks
WI8550127 · 620 served
Mequon Trail Townhomes
WI2460817 · 615 served
Huntington Park
WI2460151 · 600 served
Iron River Sanitary District
WI8040131 · 600 served
Village of Bristol Waterworks
WI2300050 · 598 served
Soldiers Grove Waterworks
WI6120252 · 592 served
North Freedom Waterworks
WI1570096 · 589 served
Delafield Square
WI2685812 · 587 served
Lena Waterworks
WI4430493 · 585 served
Wausaukee Waterworks
WI4380445 · 585 served
Autumn Ridge Water System Llc
WI1281138 · 575 served
Rocky Knoll Health Care Fac
WI4600447 · 564 served
Stetsonville Waterworks
WI8610550 · 563 served
Minong Waterworks
WI8660303 · 561 served
Kieler Sd No 1
WI1220103 · 560 served
Suring Waterworks
WI4430498 · 559 served
Ontario Waterworks
WI6630259 · 554 served
Star Prairie Waterworks
WI6560141 · 553 served
Hatley Waterworks
WI7371256 · 550 served
Phelps Sanitary District
WI7640114 · 550 served
New Auburn Waterworks
WI6090461 · 549 served
Linden Waterworks
WI1250082 · 547 served
Key Contaminant Concerns in Wisconsin
Lead
Lead is a naturally occurring heavy metal that was widely used in plumbing infrastructure until it was banned for new installations in 1986. An estimated 9.2 million lead service lines still connect homes to public water mains across the United States, along with millions of homes with lead solder in their internal plumbing.
DBPs
When utilities add chlorine to water to kill pathogens, it reacts with dissolved organic matter — leaves, algae, soil — to produce disinfection byproducts (DBPs). Over 600 DBPs have been identified. The EPA regulates two groups: total trihalomethanes (TTHMs, including chloroform) and haloacetic acids (HAA5). DBP levels tend to be highest in surface water systems and in warm months when organic matter is elevated.
Arsenic
Arsenic (As) occurs naturally in rock and soil, dissolving into groundwater through natural weathering processes. Inorganic arsenic — the form found in drinking water — is a known human carcinogen. The western United States has particularly arsenic-rich geological formations, but elevated levels have been found in 48 states. Arsenic is tasteless and odorless.
Wisconsin Water FAQs
Quick Links
Data source: Utility data from EPA SDWIS. 493 active community water systems ingested. CCR contaminant data ingestion in progress.
Last updated: 2026-04-19