Most Utah County residents were without power for 45 minutes or longer Thursday after a power line fell in south Provo and tripped breakers at substations throughout the area.
Brent Davis, a Provo Power division manager, said he believes the power outage occurred when high-load use - most likely coming from air conditioners - caused Utah Power & Light Co. lines at the Tanner Substation to warm and sag, touch some trees and start them on fire.Once the trees were in flames, the rest of the lines sagged even farther, causing the static line - a steel grounded line above the main power lines used for lightening suppression - to break and drop into the 138,000 volt high-tension wires.
Brad Whittaker, Timp district manager for UP&L, offerred another explanation. "From what we can tell, that did not occur. We think it was caused by a weak spot in the static wire, causing it to fall."
When the line fell, conductors shorted and tripped breakers, cutting power throughout the valley. The incident occurred at 12:20 p.m. Breakers were tripped at the UP&L Hale Plant at the mouth of Provo Canyon, which triggered most of the outages.
Power was out from Point of the Mountain south to Santaquin, UP&L spokesman John Serfustini said. Lines going into the Hale Plant carry power to both the north and south parts of Utah County.
Electricity was restored by 2:30 p.m. to all but a handful of UP&L customers in Orem, he said. "We were able to switch onto different circuits and restore power."
Lines that fell at the Tanner substation, 1600 S. State, Provo, also caused several brush fires, said Rod Jones, assistant fire chief. Two fire engines responded and extinguished the fires within a few minutes.
The power outage also managed to keep police busy directing traffic throughout the valley. No accidents were reported.