For the last several weeks Amtrak's Surfliner and Metrolink trains have been forced to stop running trains from south county to the San Diego County border.
"Currently both our Orange County line and our Inland Empire/Orange County line service is only operating as far south as Laguna Niguel/Mission Viejo," Metrolink spokesperson Scott Johnson said. "Metrolink each weekday traditionally would operate 12 trains south of Laguna Niguel/Mission Viejo and so approximately 1,500 riders board those respective trains."
Orange County Transportation Authority owns the right-of-way.
OCTA CEO Darrell Johnson said it's too risky to continue passenger rail service through that area.
"One issue we've all been talking about climate change, sea level rise and that sort of eroded the shore in recent years and we've been working to protect that," Johnson said. "The other issue is that the land above, or the inland side of the rail line, is slipping and sliding."
He said that's pushed the rail line about 28 inches closer to the ocean in the last 13 months.
"The option we're pursuing which will start almost immediately is very long, basically metal long nails, think 70 or 80 feet in length, at multiple points at the base of the slope or the toe of the slope at a deep angle to really try to pin that slope back so it doesn't slide further west toward the ocean," Johnson said.
OCTA hopes to have trains resume service as early as mid-December.
Metrolink is looking at the possibility of expanding its weekend service as far south as San Clemente starting on Oct. 29.