City Council Meeting Date: February 20, 2024
To: Mayor and City Council
City Administrator
From: Cole Johnson, Water Quality Specialist
Sean Simonson, Engineering Manager
David E. Bennett, PE - Public Works Director/City Engineer
Subject:
TITLE
Consider Resolution Approving Plans and Specifications and Order Advertisement for Bids for the Lincoln Waterway Box Culvert Improvement Project (STRM2022-K36).
BODY
Action Requested:
The Northfield City Council approves the attached Resolution (Attachment 1) Approving the Plans and Specifications for the Lincoln Waterway Box Culvert Improvement Project (STRM2022-K36) and Authorizes the Ad for Bid.
Summary Report:
In 2020, the City contracted with Bolton & Menk, Inc. to update the City’s surface water model as well as review and discover known and unknown localized flooding issues throughout the community but unrelated to the flooding created throughout the Cannon River Corridor. The flooding throughout the Cannon River Corridor was/is being assessed through a separate project known as the Downtown Flooding Preliminary Improvement Assessment.
Localized flooding events were reviewed after the modeling was complete and categorized based on whether or not the flooding event was a larger regional event and would benefit from City intervention and whether or not the issue could be solved from City infrastructure modification/addition or if a private property structure acquisition/modification would be required. From these characterizations, City Council gave staff direction to persue the identified flood mitigation projects that could be resolved from city infrastructure addition or modification.
On June 21, 2022 City Council authorized staff to enter a professional services agreement with Bolton and Menk, Inc. (Motion 22-416) to complete the design of one of the improvements identified in the 2020 Surface Water Model Update, known as the Lincoln Waterway Box Culvert Improvement Project. The professional services contract also includes construction observation services. City staff were also successful in applying for and receiving a grant (Planning grants for stormwater, wastewater, and community resilience) from the Minnesota Pollution Control Agency aimed at addressing current and future climate impacts throughout the state with an emphasis placed on flood control/mitigation. The grant award was $90,000 with a 10% match and would cover most expenses related to the design phase of this project.
The proposed improvement includes the replacement of an existing 2’ by 3’ box culvert with a 145’ long 6’ by 8’ box culvert of which is situated underneath an active railroad owned by Canadian Pacific Kansas City Railroad (CPKC, formerly Canadian Pacific) and operated by Progressive Rail, Inc. The existing box culvert conveys stormwater runoff gathered beginning in the northwest extents of town, throughout the neighborhoods around Greenvale Park School, and ultimately discharges into the Cannon River north of the downtown. The stormwater runoff collected in this area flows through a system of underground storm sewer networks and an open conveyance channel called the Lincoln Waterway. The existing culvert (situated between Spring Street North and Highway 3) is located underneath a 25’ berm on which the railroad tracks lie creates a bottleneck, due to it being undersized, for stormwater runoff west of this area and can cause major flooding during the 100-yr (1% chance in any given year) rainfall event. The North and South Oak Apartment Complex (a complex that provides affordable housing for income restricted residents) adjacent to the box culvert experiences the most significant effects with an approximate flooding depth of 4 feet on its first floor. This project, as proposed, will provide necessary flood relief for the North and South Oak Apartment Complex as well as several other properties situated along the Lincoln Waterway.
This project was planned in the CIP for construction in 2023, however due to the location of the project, significant coordination with the two railroad authorities was required and as a result, delayed the original construction dates to 2024. City staff plan to bring forth an agreement between the City and CPKC Railroad on March 12th for City Council to consider. This agreement would be the final step in the permitting/administration portion of the project and would allow the City to proceed with construction, assuming a successful bid opening and award.
The plans (Attachment 2) are now complete and can be viewed in the link attached to the staff report.
The basic scope of the project includes the following work. The project location is shown in Attachment 3.
• Box Culvert Construction
o Clearing and grubbing
o Removal of existing railroad tracks (done by others)
o Removal of existing box culvert (2'x3')
o Installation of proposed box culvert (6’x8’)
o Installation of rip rap energy dissipation
o Removal and resetting of nearby FES
o Resetting existing track (done by others)
o Restoration
The project required the acquisition of temporary construction easements of which one required financial compensation. These associated easement agreements and acquisition cost are detailed in a separate staff report/agenda item.
Alternative Options:
The City Council could delay this project; however, the risk for potential flood impacts and structure damage would continue to persist.
Financial Impacts:
This project will be funded through a variety of sources including bonding and the Stormwater Enterprise Fund. The City of Northfield also received an MPCA Planning Grant in the amount of $89,631.91. which has already been received by the City of Northfield. Below are the estimated project costs, and funding tables developed from the final plans.
Tentative Timelines:
See the attached project process (Attachment 4) which details the timeline for the Lincoln Waterway Box Culvert Improvement Project.