Avista Utilities (Spokane, Washington, U.S.), an operating division of Avista Corp., will begin construction in early May of a 60-mile (96.5-km) transmission line between Rosalia, Washington, U.S. and Lewiston, Idaho, U.S. The US$40 million project will provide additional transmission capacity to serve growing demand for electricity in the region. This is the last phase of a $120 million project that began in 2003.

Avista will work with International Line Builders (ILB; Tualatin, Oregon, U.S.) to construct the first 34 miles (55 km) of the project between Rosalia and Colfax, and on to Avista’s substation at Shawnee, near Albion, Washington. Construction will commence in early May and finish in mid-November.

Since the line route follows an existing Avista transmission line, ILB will first remove wood poles and wires, then install concrete reinforced foundations, erect tubular steel poles and string new conductors. The remaining 26 miles (42 km) between Rosalia and the Avista substation at Benewah, near Latah, Washington, will be constructed in 2007.

The 230-kV transmission line is designed to carry 500 MW, but can supply 1000 MW of electricity during periods of peak demand. This project is part of a larger capital infrastructure initiative that began in 2003 to meet the growing demand for the safe and reliable delivery of power to homes and businesses. It involves modernizing and increasing the capacity of Avista transmission lines and substations throughout the region.