Report reveals cause of Twisp fire

SEATTLE – An investigation by the Washington state Department of Natural Resources found that tree branches rubbing on a power line started the 2015 blaze near Twisp that killed three U.S. Forest Service firefighters.

The agency’s report says ignition likely happened as a light wind moved the branches against a sagging Okanogan County Electric Cooperative distribution line on Aug. 19, 2015. The investigation says burning foliage then dropped to the ground and spread flames. The Seattle Times obtained the DNR document through a public records request.

A utility official told investigators the power lines are maintained to standards, with trees removed every three years or whenever deemed necessary. In the area where the fire began, the lines were last cleared during the 2012-13 winter.

The report didn’t comment on the question of potential negligence.

“The fire danger rating for that area was categorized as very high, which indicated fires would start easily from all causes and immediately after ignition would spread rapidly and increase quickly in intensity,” the report said.

The investigation revealed strong evidence of the fire risks that the region’s network of power lines can create when they come into contact with trees during the peak summer fire season.

The fire 6 miles west of Twisp, Washington, killed Richard Wheeler, Andrew Zajac and Tom Zbyszewski and critically burned Daniel Lyon Jr.

The deaths and injury were a wrenching blow for the Methow Valley community – and the broader firefighting community – occurring during a historically bad fire season that burned more than 1.8 million acres in Washington and Oregon.

The Twisp River Fire eventually burned more than 11,220 acres and destroyed or damaged rural homes outside Twisp.

The Seattle Times late Friday afternoon was unable to contact Okanogan County Electric Cooperative officials for comment on the report. The utility’s website describes the cooperative as a nonprofit run by a board elected by members.