A Caterpillar hydraulic excavator moves dirt from a roadway turnoff near the large washout site.
In late December, a severe storm caused roadway washouts and slides along State Route 330 — the primary route to and from Southern California’s two most frequented ski/snowboarding mountains and Big Bear Lake.
The damage has resulted in a full closure of SR-330 for a year.
The major damage took place at one location, where a complete roadway washout and road undermining occurred. According to Caltrans District 8, an 8 ft. (2.4 cm) deep hole — directly beneath the pavement — was created when the upbound lane of SR-330 washed down into City Creek.
The hole goes completely under both lanes of SR-330 in that location.
Besides the roadway washout, landslides or culvert failures occurred in five different areas along SR-330.
“The culverts have been there a long time and they’re old,” said Raymond Wolfe, director of Caltrans District 8, adding many of the damaged culverts aren’t on the surface — rather they’re 80 ft. (24 m) underground.
Following initial clearing of debris from the roadway and inspection of the damage by Caltrans, An emergency repair project to restore the highway has been under way.
In early January, Caltrans awarded Skanska a $6 million contract for Phase I of the emergency repair work.
As part of this phase, Skanska worked around the clock to excavate the downward lane and rebuild the cavern carved under the roadbed —caused by the washout — and repair culverts at other locations in the lower section of the damaged highway.
“The work in Phase I also prepared the roadway to allow access for equipment to begin work at the major slide,” said Darin Cooke, public information officer of Caltrans District 8, adding this was accomplished by using material from the upbound lane to backfill the hole.
During Phase I, Skanska utilized a variety of standard roadway construction equipment including Caterpillar hydraulic excavators, loaders, dozers, graders, scrapers, trucks, backhoes and light towers.
In late January, Skanska was awarded a contract for Phase II work, which is the primary portion of the emergency repair efforts.
Phase II focuses on repairing the damage above the major roadway washout.
The phase will pioneer a road down to the City Creek streambed where Skanska will begin constructing a rock bolt wall — effectively carving a new alignment against the mountainside to create access for equipment to cross the large slide, according to Cooke.
Phase II is estimated at $10 million to $12 million depending on mitigation requirements for the yellow legged frog, which could cost up to $1.5 million. The slide occurred in the habitat of the frogs, which are a federally listed endangered species.
As part of the long-range project to repair the roadway washout location, Caltrans will use dirt that roared down into the creek when the area collapsed.
Caltrans will not be importing any dirt for the reconstruction project, as the transportation agency does not want to introduce any (non-native) plants or vegetation into the area. The location of the complete roadway washout is part of the San Bernardino National Forest and is overseen by the U.S. Forest Service.
Phase III of the emergency repair project has yet to be awarded and will consist of culvert/slide repair, and complete restoration of the roadway where the washout occurred. At this time, Phase III is in the planning and approval process.
SR-330 will likely be closed for all of 2011. CEG