The Bonneville Power Administration is releasing its final environmental assessment for the Northern Mid-Columbia Joint Project in central Washington along with a finding of no significant impact, or FONSI, for one of the routing alternatives.
The transmission line would provide significant benefits, including improved system reliability and congestion management, to the four funding partners: BPA and Douglas, Chelan and Grant county public tility districts. Additionally, the new transmission path would increase operational flexibility while adding capacity for future load growth for the partners. By sharing the cost among the entities benefiting from the work, funding for the project should result in less rate pressure at each of the funding utilities.
The project involves BPA funding a portion of the construction for a new, 8.4 mile-long, 230kV transmission line from Rapids Switchyard near Rock Island, Wash., to BPA’s existing Columbia Substation in Douglas County. The project would traverse both Douglas and Chelan counties. Douglas PUD would permit, construct, own and operate the new transmission line.
In addition to funding a portion of the line, BPA would install a new bay in its Columbia Substation to interconnect the line to the Federal Columbia River Transmission System. Douglas PUD would interconnect the transmission line to their Rapids Switchyard. The need for the project was identified following a 2008 Columbia Grid Study that addressed transmission system operations throughout the area and identified a “one-utility” approach to resolve several emerging needs in the mid-Columbia region.
As a result of the analysis in the environmental assessment for the project, BPA determined that one of the routes studied, West Route D - E, would not cause significant impacts. BPA decided to implement West Route D - E as described in the EA and developed a mitigation action plan to further avoid or reduce environmental impacts from the project. If all of the partners decide to go forward with the joint project, construction could begin as early as 2017.