A slumping hillside above critical railroad tracks used by freight and passenger trains in Orange County is expected to encroach on the tracks in the very near future, further complicating ongoing cleanup and stabilization efforts.
Debris and mud is expected to reach the San Clemente tracks below the Mariposa pedestrian and bike bridge by Tuesday evening, according Orange County Supervisor Katrina Foley.
That area has been the site of a hard closure since Jan. 24, when the pedestrian walkway came loose and partially collapsed as the hillside slipped from the hill above.
Crews have worked to clean up debris and stabilize the hillside, but recent record-setting storms have accelerated the rate at which the ground has moved.
Aerial view shows the slumping hillside where a pedestrian bridge came loose in San Clemente, sending debris onto the train tracks below on Jan. 24, 2024. (Orange County Transportation Authority via Katrina Foley) 
Aerial view shows the slumping hillside where a pedestrian bridge came loose in San Clemente, sending debris onto the train tracks below on Jan. 24, 2024. (Orange County Transportation Authority via Katrina Foley) 
Aerial view shows the slumping hillside where a pedestrian bridge came loose in San Clemente, sending debris onto the train tracks below on Jan. 24, 2024. (Orange County Transportation Authority via Katrina Foley)
“Due to the heavy rains over the last few days, we expect soil and debris beneath the Mariposa bridge to slide onto the railroad tracks [Tuesday night],” Foley said in a news release. “Although this is a setback, it further proves the importance of long and near-term rail stabilization solutions.”
The ongoing debris slide has heightened the danger in the busy rail corridor. Regional rail services Amtrak and Metrolink, as well as freight transporter BNSF have had to adjust to accommodate the closure.
Metrolink service remains suspended between the Laguna Niguel/Mission Viejo station and Oceanside on weekdays. Weekend service stops even further north in San Juan Capistrano.
The Amtrak Pacific Surfliner is offering rail service through San Juan Capistrano with a bus transfer between Irvine and Oceanside.
BNSF will not run any trains through the area Tuesday night due to the risk of debris reaching the tracks. Freight trains were previously pushing through the area at reduced speeds of 10 mph.
Foley, who serves as a director for the Orange County Transportation Authority, has blamed climate change for recent debris slides, which have been happening with growing regularity in recent years and bringing train traffic to a crawl. She’s called for permanent solutions to protect the tracks that run along the Pacific coastline and in the shadow of large hillsides.
OCTA previously announced plans to build a barrier wall to protect the vital rail line from future slides. The agency is also conducting a study to determine long-term solutions for a seven-mile stretch of tracks that run along the coast.
The California Transportation Commission is expected to authorize a $2 million request from OCTA to help with debris removal and other “pre-construction services,” Foley said.
Crews from OCTA and Metrolink will evaluate the state of the hill Wednesday morning.
Regular updates about the ongoing closure can be found online.
