Growth in the Wood River Valley is outstripping the capacity of existing electrical transmission lines, but Idaho Power Co. has plans to fix the problem within five years.
Company engineer Bryan Hobson presented those plans to the Hailey City Council on Monday night after outlining the growing need for electricity in the valley and the danger of winter blackouts during peak demand periods.
Hobson said he expects the Wood River Valley's population of 21,600 to swell to 76,000 when the area is fully "built-out" under current zoning laws.
"Eventually capacity will not meet demand," he said.
Hobson said the valley draws about 130 megawatts of electricity from the grid during peak hours in winter. He said 5 percent of those peak hours (111 hours) already demand enough juice to risk 20- to 30-minute "rotating" power outages, in which power is deliberately shut off to individual neighborhoods.
The outages could occur because electrical substations south of Hailey may not be able to meet demand in the valley.
Hobson said Idaho Power Co. has plans to build a new electrical substation near Burmah Road near Shoshone and lines to Hailey within the next five years to remedy the problem.
Hobson also hopes that within five years, Idaho Power can fix another, more pressing problem faced by residents of Ketchum and Sun Valley: the lack of a back-up transmission line running between Hailey and the north valley. He said if the current one is lost due to landslides, fires or any other event, the north valley could lose power until it is fixed.
Hobson said that line could be buried for aesthetic reasons, but the cost would be 10 times that of installing the lines on poles, as they are along Highway 75.
"If there are entities willing to pay for this, it could be done," he said.
Councilwoman Carol Brown pointed out that the possibility of losing power in the north valley was described as the "most-likely-to-happen risk emergency" at a meeting of a Community Advisory Committee in Hailey to address electric line concerns last year.
"If this happens the burden will fall on Hailey to help the north valley," she said.
Hailey Mayor Rick Davis congratulated Hobson on his work.
"Ketchum and Sun Valley will be glad to know that help is coming," he said.
Hobson said he hopes Idaho Power can break ground on the new line up the Wood River Valley within a year or two.
Idaho Power must first get permits from Blaine County and the cities along Highway 75 before starting work in the new line.
Tony Evans: tevans@mtexpress.com
