Pesky squirrels knock out power on Westside
Critter-related outages on rise, eclipsing falling limbs as culprits
When the power goes out on a hot day, most people assume overuse of air conditioning is to blame.
But from June 12 through July 7, four substation outages on the Westside and in North Portland were caused by adorably nimble, fluffy-tailed and unintentionally suicidal squirrels.
All four outages were in Portland General Electrics territory and one the Oak Hills substation at Northwest Cornell Road and Twin Oaks Drive in Beaverton was hit twice. By different squirrels, of course.
This is clearly an unusual convergence of squirrel activity, said Steve Corson, spokesman for PGE. Wed like to have a break from squirrels for awhile.
Heres the run-down of PGEs squirrel-related outages in recent weeks, affecting tens of thousands of customers:
Thursday, June 12, Six Corners Substation, affected 10,400 customers in Sherwood and Tualatin from 4:20 p.m. to 8:15 p.m.
Wednesday, July 2, Northwest Cornell and Twin Oaks substation, affected 10,000 customers in Beaverton, Hillsboro, Cedar Mill and Bethany from 6 a.m. to 10 a.m. The newsroom of KPTV went dark during its morning show, but the broadcast continued, powered by generators.
Sunday, July 6, North Portland, more than 8,000 customers affected in Kenton, Arbor Lodge and St. Johns areas, 8 a.m. to 10 a.m.
Monday, July 7, Northwest Cornell and Twin Oaks, affected more than 8,000 customers in Beaverton, Hillsboro and Cedar Mill areas, 8:15 to 10 a.m. Two car wrecks occurred on Northwest 185th Avenue in Rock Creek after the traffic lights went off. One driver did an illegal U-turn and hit a vehicle driven by a Washington County sheriffs deputy.
The outages left many customers in the affected areas wondering how sweet-faced squirrels could cause so much damage.
Its not all that unusual to have wildlife that does damage, said Corson. But some years, theres more squirrel activity than others.
Normally, vegetation and tree limbs are more of a problem, he added. But last year was the first in recent memory that squirrels accounted for 18 percent of outages and vegetation only 17 percent.
We have a huge tree-trimming program, which limits problems with vegetation but also controls wildlife getting into substations. We have an ongoing program of mitigation using squirrel guards of different shapes and sizes. One of the common ones is where a rubber cup goes over the insulator and out over the wire.
The Cornell substation, which has been hit twice, is receiving extra attention to prevent a squirrel-outage trifecta.
A common misperception is that squirrels running across a single power line can cause a problem.
Tom Gaunttt, spokesman for Pacific Power, explained that its not a squirrel high-wiring on a single line on your street that leads to an outage.
In a substation, he said, Yes, a squirrel runs across a line, but if they touch two, even a claw on one wire and a flick of a tail on the other, conduction kills the squirrel and knocks out power.
Pacific Power hasnt had any squirrel-related outages in recent months, but he said doves and snakes have caused problems in less-populated areas. It kind of goes in waves.
On the bright side, Corson noted that wildlife-related outages are easier and quicker to repair than other outages.
They dont damage equipment much, said Corson. In terms of duration of all outages, wildlife-caused incidents account for 6 percent of time off-line, while vegetation (fallen tree limbs, etc.) account for 21 percent of down-time.JW_DISQUS_ADD_A_COMMENT