Tidewater Contractors started paving the gravel road base last Wednesday, two months after torrential rains undermined a quarter-mile of U.S. 101 at Hooskanden Slide 12 miles north of Brookings.
Crews had to wait for dry weather to ensure the road wouldn’t continue slipping down the hillside, said Oregon Department of Transportation spokesman Dan Latham.
The first phase of work will began Monday with crews placing additional rock along the gravel roadway. Striping between the two lanes will take place two weeks after that, and in mid-August, crews will realign the highway to its original configuration.
The speed limit through the slide area will remain 45 mph until October.
ODOT says crews will rebuild the road — estimated to cost ODOT at least $1 million — to its original alignment this summer. The project will include three lanes with shoulders.
“It’s been a learning curve,” Latham said. “Last time this slid was 1996, so I’ve gotten to learn a few things.”
The road first slipped 4 inches Feb. 24, then fell 2 feet the next morning and to 12 feet below grade by that afternoon. The entire section of damaged roadway continued to slide up to 2 feet an hour, over the embankment and toward the ocean. By the time it stopped, it had slipped 100 feet below its original alignment.
Drivers were forced for two weeks to detour over Carpenterville Road, itself a steep and winding road that added about a half-hour to travel times.
When the land slowed its movement to about 3 inches an hour, crews built two ramps have been built on either end of the slide area, and moved mud at the south end to place rock. They then diverted water coming off the hill that was contributing to the movement.
By the first week of March, a single gravel lane was open to motorists — and then it started to rain again.
That rain, however, didn’t affect the new roadway, so crews set out to pave it when it dried out, Latham said.