City Council Meeting Date: September 9, 2025
To: Mayor and City Council
City Administrator
From: David E. Bennett, Public Works Director/City Engineer
Title
Downtown Flood Improvement Update and Discuss Properties at-risk for Flooding.
Body
Action Requested:
The Northfield City Council discusses Flood Risk Properties.
Summary Report:
Background Downtown Flooding
In 2020 the City received a grant for downtown flood study; the first phase of the study looked at updating Cannon River Modeling and identifying properties at-risk for future flooding. A second phase of the study was completed and provided in-depth modeling and preparing a FEMA Benefit Cost Analysis (BCA).
The BCA is a way to identify flood improvement projects that would be eligible for grant funding. The Phase II study was completed in 2023 by Council Resolution 2023-064. The City is now in Phase 3, pursuing grant funding. The attached presentation [Attachment A] provides an overview of the projects we are seeking grant funding.
Background Neighborhood Flooding
Also, in 2020 the City updated its surface water management model, to the more current rainfall data (Atlas 14). This modeling update was used to identify properties that might be at risk for flooding. The modeling identified 13 properties at risk for flooding. More detailed modeling was prepared for each of these properties to see if the infrastructure improvements could be made to the City’s storm water system to alleviate flooding. Those projects identified have received grant funding and will be under construction in 2026. In addition, the Lincon Waterway Box Culvert was replaced in 2024 reducing flood risk to the North and South Oak Apartments.
There are still five properties at-risk for flooding that couldn’t feasibly be fixed with infrastructure improvements. In 2022, staff updated its surface water management policy to provide better direction on when the City may consider assisting with flooding issues. The policy is attached for reference [Attachment B]. The City may consider assisting if it is part of the regional system causing the flooding issue.
Alternative Options:
NA
Financial Impacts:
Attached in presentation.
Tentative Timelines:
Pursuing grant funding.