Highway 236 between Acorn Drive and Jamison Creek Road will reopen today (march 26) with flaggers controlling traffic through the area.
The soil beneath the northbound lane was undermined during strong rainstorms earlier this month, leaving asphalt dangling over the edge of a ravine.
Caltrans installed a traffic light to regulate two-way traffic in the southbound lane.
On Wednesday, Caltrans closed the highway in both directions so a geotechnical crew could take soil samples.
“We need to take the geological profile of the ground,” said Barry Dunlap, resident engineer with Caltrans. “The samples help us determine where the soil stops and the rock starts.”
Knowing where the rock is tells Caltrans know how far down the retaining wall’s supports should go, he said. Those support beams anchor the wall within the ground.
Caltrans began taking the first of three soil samples Tuesday. The third and last sample will be taken today (march 26).
The soil samples, taken from 60 feet below the road’s surface, will then be analyzed before a retaining wall is designed, he said.
Those designs should take up a month or two to complete, according to Dunlap. Once that’s done, the project will be put out to bid.
After construction starts, both lanes of Highway 236 should be open for the motoring public in about a month, he said.
The cost of the project will be determined by the information the soil samples yield.