Steel poles will begin going up this week as construction gets into full swing on the upgrade of a 12-mile transmission line that will connect an Idaho Power Co. substation in McCall with one south of Lake Fork.
Idaho Power crews began drilling holes for the steel poles in late February. The line is expected to be completed in October.
"As the area has grown and demand for electricity has increased, Idaho Power has needed to add this second line into McCall," Project Manager Tom Barber said.
"That way if one line goes out of service there's another source that can meet the demand, particularly during peak winter loads," Barber said.
A second part of the project also will be completed this summer, beginning in June, when a nine-mile section of transmission line is upgraded between Tamarack Substation, located near Evergreen Forest Products, and New Meadows Substation, a news release said.
"This section we're starting to work on now is part of a larger project that will increase electric capacity and reliability in the growing communities of Adams and Valley counties," Barber said. "We plan to upgrade the existing sub-transmission power line from 69 kilovolts to 138 kV to improve the area's electric infrastructure."
At various points during the construction, Barber said that existing transmission lines feeding the area may have to be temporarily taken out of service for crews to safely complete work.
The majority of the poles will be wood, not steel. There are only a handful of steel poles that will be used at points where we need the strength such as at a corner, the release said.
"We expect the electrical work to be transparent to customers and we aren't anticipating any outages, but in the unlikely event that we lose a line to weather or an accident, our restoration time may be longer than normal," Barber said.
Last summer crews started the first phase of the project, constructing approximately 33 miles of new 138-kV line between Horse Flat Substation, near Cambridge, and Starkey Substation, north of Council. The project will eventually add more than 70 miles of transmission line to the Idaho Power system, Barber said.
Idaho Power has nearly 26,000 miles of distribution lines and 4,700 miles of transmission lines, and there are currently 262 distribution substations on the growing electric grid.
A substation's role is to step voltage down, as with the McCall and Lake Fork substations, to send it out on distribution lines to homeowners and businesses at a voltage their equipment can accept.
