The Bonneville Power Administration (BPA) and the Tillamook (Ore.) People’s Utility District (PUD) will hold a public meeting Jan. 11 to update local residents and obtain additional comments on the proposed rebuild of 10.5 miles of the Keeler-Forest Grove No. 1 transmission line and 47.3 miles of the Forest Grove-Tillamook No. 1 transmission line that run between the cities of Hillsboro and Tillamook in Washington County and Tillamook County in Oregon.
In the 295-page draft environmental assessment (EA) released Nov. 1, BPA said it needed to replace the wood poles, conductors, and other components of the 115-kV circuits that are old, physically worn and structurally unsound in places.
“These lines serve BPA’s utility customers, who in turn serve communities in western Oregon,” BPA said.
No major rebuild work has been done on the Keeler to Tillamook transmission lines since they were built in the 1950s. In general, wood poles have a 55 to 60 year life expectancy, at which time they need to be replaced due to age, rot or other forms of deterioration.
At the meeting, BPA and Tillamook PUD staff will discuss the project, the draft EA, provide updates on the scheduling and timing of the proposed work and answer questions from homeowners.
The rebuild, which is part of the agency’s ongoing effort to update aging portions of its infrastructure, would include replacement of all wood pole structures over 10 years in age, including cross arms, cross braces, guy wires, anchors, insulator assemblies, switches, and overhead conductor along the lines’ 58-mile route.
The rebuilt transmission line would be similar to the lines in design and appearance. At some locations along the lines, existing structures would be removed and not replaced, new structures would be installed that do not currently exist, structures would be moved from the existing centerline, and structures would be moved to different locations but along the existing centerline and within the right-of-way (ROW) easement. Those activities are necessary to ensure the integrity, reliability, and safety of the electrical transmission system, BPA said.
The agency also plans to use conductors slightly larger in diameter than those currently on those circuits.
In addition, the project would include improving some existing access roads to accommodate construction equipment. New road access would also be acquired or constructed in areas where access is not currently available.
The draft EA also discussed a “no action” alternative. Under that scenario, BPA would not rebuild the transmission lines and would continue to operate and maintain the existing lines in their current state.
“Line structures would likely continue to fail intermittently, the ability of BPA to provide reliable electric service to its customers in the area would be adversely affected, and the safety concerns that prompted this proposal for action would persist,” the agency said.
The project, including design and environmental work, road repairs, transmission line materials, and construction, are estimated to cost $17.5m, BPA previously told TransmissionHub.
Based on the analysis in the EA and comments received, BPA will either prepare a finding of no significant impact (FONSI) and decide whether to proceed with the project, or an environmental impact statement (EIS) if there is the potential for significant environmental impacts.
If it decides to proceed with the rebuild, BPA anticipates issuing the final EA and FONSI in January, hopes to award a contract in the spring if it decides to proceed, and have work completed in December 2014.