Duluth Finalizes Violation Agreement with MPCA After Tischer Creek Fish Kill

Duluth city officials finalized a violation agreement with the Minnesota Pollution Control Agency Feb. 23 and the City Council signed off on paying a $12,000 civil penalty and agreed to reinvest in brook trout habitat after a 2024 discharge killed fish in Tischer Creek. Public Works Director Jim Benning presented the briefing to the council, joined by utility operations staff including Utility Operations Coordinator Ryan Granlund.

The MPCA traced the release to maintenance work at a city reservoir and reported that about 1.7 million gallons of chloramine-treated potable water entered the storm sewer system, flooding roughly 2 miles of Tischer Creek over about 15 hours. The agency’s probe found chloramine concentrations at levels it described as four times the lethal level for brook trout, and multiple outlets cited the MPCA finding that the discharge did “extensive harm” to the creek’s broader ecosystem. Officials and news reports emphasized the treated water was not toxic to humans.

Estimates of fish mortality vary across reports. The Star Tribune cited the MPCA as saying the release killed nearly 1,600 brook trout and hundreds of other fish. The Duluth News Tribune described “the documented death of more than 2,000 fish in about a two-mile stretch,” while Northern News Now used the phrasing “more than 1,000 dead fish found along Tischer Creek.” At council briefing, Granlund told members the August 2024 release of about 1.7 million gallons “did cause significant environmental harm.”

Enforcement actions spelled out in the finalized agreement include the $12,000 civil penalty and an MPCA order that the city invest $190,000 in brook trout habitat restoration projects chosen by the MPCA and the Minnesota Department of Natural Resources. The Duluth News Tribune framed the total financial impact as $202,000, combining the penalty and the restoration order. Councilors “signed off on paying the civil penalty Monday evening” and discussed restoration options at the Feb. 23 meeting.

Councilor Diane Desotelle acknowledged the city’s responsibility in the briefing, saying, “None of us are happy that this happened,” and, “This was a mistake, and we've learned a lot from it. We've owned it.” Desotelle added thanks for the city’s planned actions and said the recovery plan “represents an opportunity to improve the future health of Tischer Creek,” likening the effort to “taking a lemon and making it into lemonade.”

Planned restoration work referenced by city reporting and state direction includes removal of a low-head dam upstream of West Lewis Street to reopen spawning access, projects to reduce dirty sediment flows from a tributary, water-quality improvements at Hartley Park, and expanded trout programs. The MPCA and Minnesota DNR will select specific brook trout habitat projects under the $190,000 order. The finalized violation agreement closes the MPCA probe while committing municipal and state resources to repair damage along the designated trout stream.