About 2,000 Central Electric Cooperative members in the Tumalo area had a very warm Tuesday afternoon after a 69,000-volt power line that feeds the Tumalo substation went out, sending repair crews on a challenging, hours-long hunt for the cause.
The power was back on around 4:10 p.m., nearly three hours after it began, after crews removed a juniper tree that had grown into the line, which sagged in the hot weather, touched the tree and short-circuited, said Jeff Beaman, member services director.
The outage was largely in Tumalo, along with areas west and south of town, north to areas adjacent to Innes Market and Marsh roads, and southeast to areas near Highway 20 and Cooley Road.
Once the problem tree and another nearby that presented a similar threat were removed, crews determined no major repairs to the line were required and it was re-energized, Beaman said.
In hot weather, power lines often sag due to the expansion of the metal conductor. The situation is aggravated when the line is under heavy load, primarily due to air conditioner use this time of year.
A tree that poses no threat to contacting the line most of the year can become a problem during a heat wave, he explained.
In addition to the trees removed Tuesday, Beaman said CEC will remove others in the vicinity that could present a similar problem should they grow much taller.
It took some time for crews to narrow their search for the problem from a nearly nine-mile stretch of line to one of about two miles.
Beaman said the search was prolonged because much of the section of line is along the back lines of private property, with no road access, so crews had to reach the area on foot.
Around 3:30 p.m., officials said crews had traced the outage to a section of line in the Highlands subdivision, north of Tumalo.
"This is hampered further by property owners’ placement of obstacles such as fences between parcels," he added in a posting to CEC's online outage blog, where you can track updates at http://www.cec.coop/outage .
During the outage, CED reported high call volumes and urged members to dial toll-free 1-866-459-8651 and access a recorded message providing information about the outage.