Updates to Sheyenne River Aqueduct Structure plan mean positive benefits for West Fargo and Horace
The West Fargo City Commission recently voted to support mitigation measures that provide benefits for the FM Area Diversion Project, as well as the cities of West Fargo and Horace. The Project will increase flood protection from a 100-year event to a 500-year event.
Joel Paulsen, Executive Director of the FM Area Diversion Project attended the Commission’s November meeting to present a concept that would update flood protection infrastructure for the City of West Fargo. The updates would also result in positive changes and cost savings for elements of the FM Area Diversion Project.
“We are constantly looking for ways to incorporate different changes to offset the effects we have based on our physical footprint,” Paulsen told the Commission.
Currently when the Sheyenne Diversion operates to protect West Fargo and Horace from flooding, there are positive flow barriers that stop water from flowing naturally in through the Sheyenne River. The system has been operated many times since its completion in 1992.
Paulsen presented several modifications to the planned Project that would result in lowering the level of water flowing through the Sheyenne Diversion as well as a continuous flow of water passing in the natural riverbed throughout West Fargo. The modifications will also allow for a smaller amount of water to flow across the Sheyenne River Aqueduct Structure component of the FM Area Diversion Project. A smaller structure could mean cost savings for the Project.
The aqueduct has a spillway that allows excess floodwaters into the main Diversion Channel. It will allow a set level of water to flow over the Diversion Channel and continue through the existing Sheyenne Diversion and Sheyenne River.
Once the aqueduct is complete and the FM Area Diversion Project is certified and operational, the modifications to the current flood protection systems could be updated, City Engineer for West Fargo, Dustin Scott explained. Scott outlined how engineers have been drafting plans for how the Horace and Sheyenne Diversion Flood Control Projects could be updated once the FM Area Diversion Project is built. The updates would include removing some of the structures currently in use, including those that prevent water from flowing into the Sheyenne riverbed.
The new aqueduct being built will help West Fargo balance the flow of water between the existing diversion channels and the new, larger channel being built by the Diversion Authority. Scott explained that the changes had to result in the same, or more, protection from floods for West Fargo residents. They will also help reduce some maintenance costs to the existing systems, and improve the ecology and streambank stability of the Sheyenne River by maintaining a flow of water in the riverbed all the time.
“The goal is to improve the environmental state of the Sheyenne river. This has been a serious point of discussion and one that we have been working on extensively over the last several months,” Scott explained. He also noted the cost for this work would be covered by the Diversion Authority, not the City of West Fargo.
“This is an opportunity to leverage the FM Diversion Project to improve our current flood protection system,” Scott said. West Fargo City Commissioner Mike Thorstad, a member of the Diversion Authority, expressed his support for the effort.
The changes will be studied further and incorporated into the design and operations plan for the FM Area Diversion Project. The Commission unanimously approved a motion to support the further development of the mitigation measures.