City of Traverse City Flooding Impacts
Closures, Safety Measures, Damage Reporting
Updated April 23, 2026
Self-Reported Damage Assessment
Grand Traverse County's Equalization and GIS logistic team is responsible for assessing all flooding impacts to private and public properties throughout the county. Taking a moment to fill out this self reporting survey will help them gain an understanding of the extent of damages in your specific area.
Closures & Recovery
Portions of Lot A, in the alley north of the 100 block of E. Front Street, have been closed due to a sinkhole in the area. Remediation began this week. Expect intermittent closures of the alley into next week. Additionally, portions of Lot K remain closed due to erosion on the riverbank.
Brown Bridge Quiet Area
The Grasshopper Creek pedestrian bridge at trail marker 5 continues to be closed. Assessments are being made on the condition and remediation. Please proceed with extreme caution on any trails.
Last week’s storm event pushed the Boardman/Ottaway River system to levels rarely seen in recorded history—highlighting just how extreme the conditions were.
Historic River Levels
Due to roadway washout, the U.S. Geological Survey (USGS) gage station at Beitner Road was unable to capture the river’s peak flow. However, data from the next available upstream station—located above Brown Bridge Road near Mayfield—provides important context.
At that location, the previous record peak flow, dating back to 1949, was 583 cubic feet per second (cfs), recorded on April 14, 2014. On April 14, 2026, the river surged to 1,120 cfs—exceeding the prior 77-year record by 92 percent.
Closer to downtown, at FishPass, water levels upstream of the labyrinth weir came within just half an inch of what is classified as a “500-year flood.” While the term can be misleading, a 500-year flood does not mean it occurs once every 500 years. Rather, it represents a flood event with a 0.2 percent chance of occurring in any given year.
Infrastructure Investments Make a Critical Impact
While the scale of the storm was historic, recent infrastructure improvements played a significant role in reducing what could have been far more severe impacts to the community and environment.
In 2023, the City completed two key projects along the Boardman/Ottaway River corridor: the sanitary sewer relocation in the 100 block of East Front Street and river wall stabilization in the 200 block. During last week’s event, a sinkhole formed in Lot A along the river wall, exposing an abandoned 24-inch sanitary sewer that included a compromised service connection with a six-inch hole in its side.
Because that aging trunkline had already been relocated and replaced with a new 30-inch main in the center of the alley, a major environmental incident was avoided. Without that proactive investment, an estimated 1.5 million gallons per day of raw sewage could have discharged directly into the river and ultimately Grand Traverse Bay.
More recently, in 2025, construction of the FishPass labyrinth weir introduced a modern, resilient system designed to better manage extreme flow conditions. During last week’s storm, the weir performed as intended, safely conveying significantly higher volumes of water than the former Union Street Dam was capable of handling.
Engineering analysis indicates that a storm event of this magnitude could have overwhelmed the former dam structure, potentially leading to failure and uncontrolled flooding of Boardman Lake into Downtown. Even in a scenario where the dam remained intact, upstream water levels would have risen significantly higher, placing additional strain on the City’s wastewater treatment plant by limiting discharge capacity and increasing the risk of system impacts.
Higher upstream water levels could have also extended beyond the immediate Downtown area, with the potential to compromise infrastructure such as the culverts near S. Airport Road at Logan’s Landing.
These investments reflect the City's broader focus on modernizing critical infrastructure, not only to meet current needs, but to build resilience against increasingly unpredictable and severe weather events.