EPA data as of Oct 2026 · page updated 2026-10-30

City of Beloit

City of Beloit (EPA ID WI1540112) in Beloit, WI supplies groundwater (wells) to about 36,677 people: 2 violations since 2016, latest lead result 4.5 ppb, PFAS 1 detected.

Service area

EPA service-area boundary (state-supplied or EPA-modeled)
Water utility service area PFOA/PFOS ≥ 4 ppt Lead > 15 ppb 5+ violations Superfund site (active) proposed cleaned up Circles: other water systems flagged nearby; size = people served. Tap any symbol for details.

System facts

People served36,677
Connections13,584
Sourcegroundwater (wells)
WholesalerYes

Health-based violations

Contaminant or ruleHealth-based violations since 2016
Combined Radium (-226 and -228)2

A health-based violation means a contaminant exceeded its legal limit (MCL) or a required treatment technique was not met, as reported by the state to EPA’s SDWIS. All are listed as resolved or archived; the latest began Oct 2019.

Lead

Jun 20234.5 ppb
Jul 20207.1 ppb
Jun 20176.6 ppb
Jun 20145.5 ppb
Jun 20119.3 ppb
Jan 20087.3 ppb
Jan 20058.8 ppb
Jan 20024.9 ppb

90th-percentile lead per sampling round (90% of the homes sampled were at or below this level). Black line: EPA’s 15 ppb action level; under the Lead and Copper Rule Improvements the action level becomes 10 ppb from 2027.

PFAS

CompoundHighest resultSamples with detectionEPA limit
PFBS3 ppt1 of 14—
PFHxAnot detected0 of 14—
PFDAnot detected0 of 14—
PFOAnot detected0 of 144 ppt MCL
PFOSnot detected0 of 144 ppt MCL
PFHxSnot detected0 of 14—
PFHpAnot detected0 of 14—
HFPO-DA (GenX)not detected0 of 14—
PFBAnot detected0 of 14—
PFNAnot detected0 of 14—
PFPeAnot detected0 of 14—

EPA Fifth Unregulated Contaminant Monitoring Rule (UCMR 5), samples 2023–2025; ppt = parts per trillion (ng/L). The 4.0 ppt maximum contaminant levels for PFOA and PFOS were set by EPA in 2024; water systems have until the end of the decade to comply.

ZIP codes served

ZIP codes whose center lies in this system’s service area.

What this is — and isn’t. These are records your water utility and state reported to the EPA, and the EPA’s radon map for your county. They describe the system and the area, not the water from your own tap or the air in your home. For that, read your utility’s annual Consumer Confidence Report and test: lead and radon tests are inexpensive.

Questions

Has City of Beloit had drinking water violations?

Health-based violations since 2016: Combined Radium (-226 and -228). All are listed as resolved.

What is the lead level in City of Beloit water?

The latest 90th-percentile lead result (Jun 2023) was 4.5 ppb. EPA’s action level is 15 ppb (10 ppb from 2027).

Does City of Beloit have PFAS in its water?

PFAS were detected, with PFOA and PFOS below 4.0 ppt (highest not detected).