One week after a 40- to 50-ton boulder closed Highway 243 between Idyllwild and Pine Cove, this is what remains on the shoulder of the highway Tuesday morning. Photo by JP Crumrine
One week after a 40- to 50-ton boulder closed Highway 243 between Idyllwild and Pine Cove, this is what remains on the shoulder of the highway Tuesday morning.
Photo by JP Crumrine

“All lanes on SR 243 are open,” Cal Trans Public Information Officer Terri Kasinga announced Wednesday night, Jan. 13.

That was a relief for many after late Sunday night, Jan. 10, when a 40- to 50-ton boulder fell on Highway 243 between Idyllwild and Pine Cove. Monday morning, Caltrans closed the highway, disrupting the route between the two communities.

That same day, Caltrans geotechnical engineers investigated the slope at the location where the boulder fell onto the highway and determined that once the boulder was removed, it would be safe to reopen the route to the public, according to Kasinga.

After his evaluation, Brian Hinman of Caltrans Office of Geotechnical Design said, “Rocks fall as a natural process of the mass wasting of the mountains. Typically they fall as the rock weathers. We have perfect weather with the warming and snow melting and water flowing into the fractures.”

In order to reduce the boulder’s size so that it could be moved off the highway, Caltrans ordered special equipment — a 50,000-pound excavator equipped with a hydraulic breaker.

However, on Tuesday, the boulder broke the excavator’s drill bit. A replacement was ordered. By Wednesday evening, Caltrans had chipped enough of the boulder that it could be moved off the highway, permitting traffic use to re-start.