Chapin sewer overflow sends diluted sewage into Mauvaisterre Creek, water safe

The question for Chapin residents was immediate: did the sewer overflow mean the water coming out of the tap was unsafe? Village officials said no, separating a storm-driven sanitary sewer overflow into Mauvaisterre Creek from the drinking-water system people use every day.

A sanitary sewer overflow is a release of untreated or partially treated sewage from a municipal sanitary sewer system. The U.S. Environmental Protection Agency says these overflows can happen during heavy rain, blockages or other system problems. The agency also distinguishes sanitary sewers from combined sewer systems, which are designed to carry both sewage and stormwater. That difference matters in Chapin, because a sewer problem can affect a creek without automatically threatening drinking water.

Chapin’s annual drinking-water report for Jan. 1 through Dec. 31, 2025 lists the village’s source as “Purchased Ground Water Under Direct Influence of Surface Water.” The report gives residents a way to track the water system separately from the sewer system, and the village’s message about the overflow was meant to keep those two issues from being confused. The overflow sent diluted sewage into Mauvaisterre Creek, but the village framed it as a storm-related wastewater event, not a drinking-water emergency.

That distinction also matters for accountability. Unauthorized sewer overflows into U.S. waters can violate the Clean Water Act, and Illinois Answers Project reported in June 2025 that five dozen communities in Southern Illinois and the Metro East accounted for a third of Illinois’ reported sanitary sewer overflows over the previous decade. In other words, Chapin’s problem is local, but it is part of a larger infrastructure strain that hits small communities hard when major rain overwhelms aging systems.

The Village of Chapin Department of Public Works is the local contact point at 510 Everett Street. Public Works Superintendent Trevor Cawthon and Wastewater Operator Dr. Bryce McCormick are listed on the village website, and residents can call (217) 472-3111 for the water-quality report. Morgan County Health Department’s Environmental Health division also handles sewage-related oversight, giving county officials a role if monitoring or follow-up is needed after the overflow.

For Chapin, the immediate takeaway is clear: the sewer system took the hit, Mauvaisterre Creek received the overflow, and officials said the drinking water remained safe. The larger question is how often the village will face the same stress when the next major storm arrives.