Report finds 'advanced decay,' wind led to collapse of 26 power poles in Tukwila

TUKWILA, Wash. -- An investigation into what caused more than two dozen utility poles to collapse revealed that several of the poles had rotten cores.

Back in April, 26 power poles came cascading down, crushing a car and sending two people to the hospital.

The incident also knocked out power to 16,000 Seattle City Light customers at the time.

The investigation by the city attorney's office determined that six poles were severely decayed. Strong winds caused the poles to snap.

Three other poles were infested with beetles.

Seattle City Light will now change the way it inspects its 91,000 poles and will work to replace thousands of weak poles.

City Light told the Seattle Times it does not know how long it will take to replace the 6,000 substandard poles.