WENATCHEE, Wash. -

Investigators have determined that a summer wildfire near Wenatchee was caused by faulty electrical wiring in a cherry grower's irrigation pump house.

KPQ reports the determination was announced in a final report by the Washington State Department of Natural Resources on the Colockum Tarps Fire that covered about 66 square miles

State officials say they will seek to recover the $11 million firefighting cost. The fire destroyed four homes and several outbuildings and forced the evacuation of dozens of residents. The wildfire began on July 27 and spread across two counties.

The irrigation system is owned by a longtime local orchardist.