A major infrastructure project in Oconomowoc took a dramatic turn Monday afternoon when the Lapham Street bridge under construction next to Riverside Park suddenly collapsed, Mayor Matt Rosek said. The partially built structure dropped into the river during a concrete pour, but officials say there were no injuries.
City leaders and state engineers headed straight to the site, where Rosek said he demanded that the contractor handle an emergency cleanup. According to the city, the collapse happened while crews were placing concrete and temporary support under the pour gave way, sending part of the bridge into the water.
Officials: Temporary Support Gave Way During Concrete Pour
Rosek first announced the collapse on Facebook, then visited the scene with city staff. He wrote that the city had “demanded the contractor clean this up on an emergency basis,” signaling frustration and urgency in equal measure.
The Wisconsin Department of Transportation told the station that a falsework beam supporting a concrete pour failed and confirmed that no construction workers were hurt. Officials also told the outlet that the replacement project had originally been scheduled to run into September, according to TMJ4.
Project Background And Timeline
Work to replace the single-lane 1950s Lapham Street span kicked off in mid-February. The city’s plan called for demolishing the existing bridge and building a new two-lane structure with shoulders and raised sidewalks to better handle modern traffic and pedestrian needs.
According to the project information, work had been expected to wrap up in the summer of 2026. The city’s project page also offers a sign-up for construction updates so residents can track progress and disruptions as they happen, according to the City of Oconomowoc.
Cleanup And What Residents Should Know
Rosek said the city has ordered an immediate cleanup, and crews have cordoned off the work zone while officials take a hard look at the debris and what remains of the temporary supports. WisDOT and city staff gave the initial rundown of what happened, but they are not yet ready to say how the collapse will affect the overall schedule.
An updated construction timetable has not been released while engineers and inspectors continue their assessments, as reported by TMJ4.
How To Follow Updates
The city’s Lapham Street project page remains the main hub for official information, with contact details and a “Notify Me” signup for construction alerts and updates. Residents looking for the latest on scope, timing and project contacts can find it on the City of Oconomowoc project page.
