Falling boulders close stretch of highway near Waimea Bay

About a dozen boulders, some the size of car engines, came rolling down the hillside near Waimea Bay at about 2:30 a.m. yesterday, a state official said.

Most of the rocks hit a protective barrier installed by the Department of Transportation after a rockslide on the Sunset Beach side of Waimea Bay Beach Park in 2000, said spokesman Scott Ishikawa.

"The good news is the fence did hold up," he said.

The rockslide forced a shutdown of Kamehameha Highway for a couple of hours. It was contra-flowed during morning rush hour traffic and reopened at 9 a.m., Ishikawa said.

One large boulder rolled through an unprotected area just to the right of the barrier on the Waimea Bay side.

Transportation workers placed concrete barriers up in that area. Two sand barrels were sliced open by the boulder and likely protected passing cars.

"One boulder was stuck in a tree -- the size of a car engine," Ishikawa said, adding that it will likely not be removed.

The barrier, installed at a cost of $4 million, provides a double layer of protective fence, with a chain-link layer and a metallic-ring layer.

Ishikawa speculated that the recent rainy weather could have eroded the soil, causing the boulders to loosen, he said.

The boulders did not come from directly above the barrier, but rather originated from three different parts of the hillside, about 75 to 100 feet up, he said.

"They just happened to roll down the right way," Ishikawa said.

The boulders splintered a couple of trees and created a hole six feet above the ground in the double-layer protective fencing, but the fencing held up.