Spokane-based Avista Utilities says it has begun work on a $21.5 million transmission-system upgrade on the Palouse thats the final phase in a $131 million regionwide upgrade the utility started in 2003.


The 26 miles of high-voltage 230-kilovolt transmission line in the final phase will stretch from Avistas substation in Rosalia, Wash., to its Benewah substation located to the northeast, roughly halfway between Latah, Wash., and Plummer, Idaho, says the utility, which is a division of Spokane-based Avista Corp.


The current project is one of six major pieces of work in the overall transmission system upgrade. Those projects, which have included some substation work, have stretched from Noxon, Mont. through the Spokane-Coeur dAlene area south to the Lewiston, Idaho-Clarkston, Wash. valley.


Avista is upgrading its system to meet growing demand for electricity across the Inland Northwest, and the improvements will make the system more reliable by increasing redundancy, says Avista spokesman Hugh Imhof.


The current project is part of the final $45 million, 60-mile leg of the upgrade. Work on the first part of that leg, which started last year and is nearing completion, includes construction of about 34 miles of transmission line from Rosalia to Colfax, Wash., and farther south to an Avista substation near Albion, Wash., Imhof says.


The project thats starting this year is expected to be completed in late November, weather permitting, he says. Spokane-based Hawkeye General Contractors Inc. is the contractor, and Meckel Engineering & Surveying Inc. and Ruen-Yeager & Associates, both of Coeur dAlene, are doing surveying work.


The work involves installing up to 130-foot-high tubular steel poles, anchored by concrete-reinforced foundations sunk as deeply as 25 feet into the ground, and stringing conducting wire on the poles. Hawkeye also will remove wooden power poles and wires from an older power line along that route, Imhof says.


A 230-kilvolt transmission line is designed to carry 500 megawatts of electricity, with a capacity to carry 1,000 megawatts of electricity during periods of peak demand. One megawatt is enough power to meet the electrical needs of about 650 homes.


Contact Emily Brandler at (509) 344-1265 or via e-mail at emilyb@spokanejournal.com.