City Council Meeting Date: May 3, 2022
To: Mayor and City Council
City Administrator
From: David Bennett Public Works Director/City Engineer
Title
Consider Resolution accepting Downtown Flood Study Report Recommendations and authorizing Phase 2 - FEMA Benefit Cost Analysis.
Body
Action Requested:
The Northfield City Council accepts Downtown Flood Study Report Recommendations and authorizing Phase 2 - FEMA Benefit Cost Analysis.
Summary Report:
The City, over the last 10 years, has had numerous flooding events of the Cannon River causing damages to properties and public infrastructure. Due to this, City Council approved an Advanced Assistance Grant with the State of MN Homeland and Emergency Management. Barr Engineering is performing the study for the City.
There are three phases to the project study, only Phase 1 draft report is what is presented to Council this evening.
Phase 1 - Study and Identify Downtown Flood Improvement Options and identify costs for the improvements.
Phase 2 - Complete FEMA Benefit Cost Analysis.
Phase 3 - Identify Eligible Project and Prepare Plans for construction.
There are five properties north of the Fourth Street Bridge along the Riverwalk, three properties south of the Fifth Street Bridge, and three City park properties (Ames Park, Riverside Park and Babcock Park) included in the Study (Attachment 3).
The draft flood study report reviewed the flood history, flood frequency, estimated new peak flood flows and elevations. With this information, alternatives were developed, cost estimates, and draft recommendations.
The flood alternative that were reviewed as study include:
• Leave as is
• Property Acquisition/Buyouts
• Floodwalls/Levee
• Wet Floodproofing - Allows the water in
• Dry Floodproofing - Keeps water out
• Temporary Barriers
On March 8, 2022, staff presented that draft recommendation in the Phase 1 study to Council and held a public meeting with property owners on April 7, 2022.
At the public meeting on April 7, the property owners seemed favorable to the recommendations and supportive of the City to move to the next phase of the project, Phase 2 - the FEMA Benefit Cost Analysis.
Tonight’s action will accept Phase 1 - recommendations and authorize staff to move to Phase 2. Phase 1 recommendation include:
Area 1 - West side North of 4th Street Bridge (301 Water St., 207 Water St., 205 Water St.)
• Recommendation is to move the Alt 1-2 Floodway Extension to Phase II
Area 2 - East side North of 4th Street Bridge (11 Bridge Square, 13 Bridge Square)
• Recommendation is to move the Alt 2-2 Dry Floodproofing to Phase II
Area 3 - South of Fifth St. - East side (500 Water St., 516 Water St., 630 Water St.,)
• Recommendation is to move the Alt 3-2 Dry Floodproofing to Phase II
Alternative Options:
Financial Impacts:
Financial impacts will become clearer after Phase II Benefit Cost Analysis of the study.
Tentative Timelines:
Sharing of Draft Report March 15 - April 15, 2022
City Council Considers Phase 1 Report and Authorized Phase 2 May 3, 2022
Phase II Study - June 2022 - Dec 2022