Hawaiian Electric Co. is inspecting more than 100 utility poles along the Wai'anae Coast in the wake of the dramatic toppling of a dozen poles on Sunday.

Hawaiian Electric spokesman Jose Dizon said it will probably take a week to complete the inspection of the poles between the Kahe power plant and Hakimo Road. The company this week began analyzing whether termite damage or some other factor played a role in the poles falling during a period of high winds.

The poles fell across four lanes of traffic on Farrington Highway at about 1 p.m. Sunday, at about the time that the National Weather Service forecast 60 mph winds sweeping down the mountains. As many as 20 cars were damaged but no serious injuries were reported. Traffic was disrupted for hours while the area was cleaned and the power lines reconnected.

Dizon explained that most of the 72,000 utility poles across O'ahu are jointly owned by the electric, cable and telephone companies. About 15,000 poles are owned outright by HECO, Dizon said.

The 65-foot wooden poles generally last about 30 years. "We inspect them in a three-to-five year cycle," he said. This week, a HECO official said the utility poles are designed to withstand winds of 56 mph.

Damaged poles may be reported by calling the company's customer service line at 548-7311.

Reach Robbie Dingeman at rdingeman@honoluluadvertiser.com.