As excavation crews wrap up clearing out a clogged sewer pipe that may have contributed to recent flooding in Milwaukee’s Bay View neighborhood, new details are emerging about what went wrong and when.
On July 16, construction workers with Michels Corporation pulled the last bit of debris − sticks, muck and plastic trash − from a dual box-culvert sewer beneath Jones Island off South Carferry Road. The two concrete boxes, each about 6.5 by 7.5 feet, had been packed with roughly 20 truckloads of material, about 15 cubic yards per load.
The debris created a 420-foot clog in the sewer, located roughly a half mile from the pipe’s discharge point into Lake Michigan.
The Journal Sentinel was first to report about the 87-year-old stretch of pipe that the Milwaukee Metropolitan Sewerage District says may never have been inspected − a buried choke point lurking out of sight until the floods in last August and April hit.
According to MMSD, it will take a few weeks to determine if, and to what extent, the clog contributed to flooding in Bay View and any surrounding areas.
MMSD first learned there was debris in the sewer in September 2024, while building a new pollution storage facility that will hold the next round of PCB‑laden sediment dredged from Milwaukee’s rivers and harbor. The combined sewer pipe − one of only two that empty directly to Lake Michigan − had to be moved north of where the nearly completed pollution storage facility now sits. Combined sewer pipes carry both wastewater from toilets and sinks, and stormwater runoff from rain and snowmelt.
It wasn’t until after the week‑long April rain event that Pat Obenauf, manager of contract compliance at the district, looked at the flow data MMSD reports to the state and realized “something doesn’t look right.”
“And that’s when we realized this must be blocked,” he told the Journal Sentinel on July 16. “It’s not just debris in the sewer, it’s blocking the sewer.”
One working theory is that when Lake Michigan dropped from record highs in 2020 to lower levels in 2021, the pipe’s discharge opening may have been exposed just enough for floating debris to wash in. Under normal conditions, the opening sits underwater, which should keep that kind of material out.
The Mothership, a Bay View bar on South Logan Avenue, has become a high‑profile symbol of the neighborhood’s flooding woes. Its basement took on water during the record August 2025 storm and again as a result of the heavy April 2026 rains, forcing repeated closures and costly repairs.
Marina Dimitrijevic, alderwoman for Milwaukee’s 14th District, which includes Bay View, slammed MMSD’s lack of transparency and called for restitution on behalf of residents and business that had flooded. Dimitrijevic had been pressing for answers on why Bay View remained a flooding hotspot despite not having a waterway nearby, like other hard‑hit areas in the city. When the clog was identified as the possible source, she was livid.
Construction, cleanup of clog began early June
Beneath Milwaukee, more than 3,000 miles of laterals and sewer pipes snake through the city − a network longer than the distance across the continental U.S. The sewerage district oversees about 300 miles of those regional pipes.
While most of the pipes are monitored regularly with cameras, this particular stretch, Obenauf said, is extremely hard to access because it sits deep upstream and under water.
Construction to relocate the combined sewer pipe − one where stormwater and wastewater flow together − began in early 2025, a job Obenauf said was challenging because it was on the Port of Milwaukee’s property and had to ensure the line wasn’t contaminated with PCBs.
Work on the relocation didn’t wrap up until early 2026, and by that time the historic August 2025 storm had swamped the city, causing hundreds of millions of dollars of damage. Because that storm was so extreme, and affected so many areas, Obenauf said, the district didn’t initially realize anything was amiss.
After more flooding occurred in April, however, the district sensed something significant was going on underground, and an urgent investigation began.
That’s when the clog was discovered.
Michels, already onsite to build the pollution storage facility, was able to start the cleanup shortly afterward. Removal of debris began on July 9.
Dimitrijevic criticized MMSD for not informing Bay View residents and businesses until now.
Obenauf said the agency was focused on getting the work done as soon as possible.
“It’s easy to say right now, yes, we should have told them earlier,” Obenauf said. “Until we actually got these crews in to see how bad it was, we really didn’t know for sure.”
Caitlin Looby covers the Great Lakes and the environment for the Milwaukee Journal Sentinel. Contact: clooby@gannett.com. Follow her on social media @caitlooby.
Caitlin is an Outrider Fellow whose reporting also receives support from the Brico Fund, Fund for Lake Michigan, Barbara K. Frank, and individual contributions to the Journal Sentinel Community-Funded Journalism Project. Journal Sentinel editors maintain full editorial control over all content. To support this work, visit jsonline.com/support. Checks can be addressed to Local Media Foundation (memo: “JS Community Journalism”) and mailed to P.O. Box 85015, Chicago, IL 60689.
This fundraising effort is made possible through our partnership with Local Media Foundation, a verified 501(c)3 nonprofit organization (tax ID #36-4427750) and EnMotive Company, LLC, a subsidiary of USA TODAY Co., Inc. USA TODAY Co., Inc. is the parent company of this publication.
The JS Community-Funded Journalism Project is made possible through our partnership with Local Media Foundation, tax ID #36-4427750, a Section 501(c)(3) charitable trust affiliated with Local Media Association, and EnMotive, LLC, a subsidiary of USA TODAY Co., Inc. USA TODAY Co., Inc. is the parent company of this publication.
This article originally appeared on Milwaukee Journal Sentinel: Exclusive | New details emerge about pipe that may have caused Bay View flooding
Reporting by Caitlin Looby, Milwaukee Journal Sentinel / Milwaukee Journal Sentinel
USA TODAY Network via Reuters Connect
By Caitlin Looby, Milwaukee Journal Sentinel | USA TODAY Network
