A new 15,500ft long bypass channel is to be built at the Lower Yellowstone Intake Diversion Dam in Montana, US, under plans selected by the US Army Corps of Engineers (USACE) and Bureau of Reclamation (USBR).
The federal agencies signed a Record of Decision (ROD) on 5 December for the project selecting the Bypass Channel Alternative and associated Adaptive Management and Monitoring Plan (AMP) for implementation.
"Signing the ROD is the final step in the process that highlights the efforts of so many people," said Col. John W Henderson, Omaha District commander for the Corps. "This is a positive step forward in getting this project off the ground."
The Bypass Channel Alternative was selected because it best meets the purpose and need of improving pallid sturgeon fish passage and ecosystem restoration while continuing viable and effective operations of the Lower Yellowstone Project, the agencies said in a statement.
This alternative involves constructing the 15,500ft long bypass channel from the upper end of the existing side channel, to just downstream of the existing diversion dam.
"The Bypass Channel Alternative provides the best opportunity for fish and farms to coexist," said Reclamation's Great Plains Regional Director Mike Ryan. "I also would like to recognize the Army Corps of Engineers commitment of resources and seeing the process through for the people of Montana and North Dakota."
The Bypass Channel Alternative is expected to improve pallid sturgeon passage at Intake Diversion Dam and contribute to ecosystem restoration. At the same time, while an increase in operations and maintenance costs is expected, it is not anticipated to disrupt operation of the Lower Yellowstone Project.
Construction of the approximately $57 million Bypass Channel project will be funded and managed by USACE and is expected to begin as early as the spring of 2017 and take approximately 28 months to complete. USACE and USBR will implement the AMP beginning in 2017. The Lower Yellowstone Irrigation Project Board of Control will be responsible for the long term operation and maintenance of the project and for certain aspects of the AMP.