Caltrans crews will conduct emergency repairs to Highway 1 at Rat Creek starting Monday, March 1.
Officials estimate the road will reopen early this summer.
Debris flow from the Dolan Fire burn scar washed out a 150-foot section of Highway 1 on January 28, causing the road to be closed indefinitely.
After assessing the damage, Caltrans plans to reconnect the roadway at Rat Creek with an enhanced fill option, which means crews will fill the canyon with dirt in a large V-shape and then build a new road on top.
“Highway 1 is an iconic roadway that connects travelers with small businesses on the Central Coast, and we’re focused on restoring travel on this section by early summer," said Caltrans Director Toks Omishakin.
In addition to filling the hole with dirt, crews will replace the main drainage system and install a main culvert, secondary culvert and smaller overflow culverts to the highway grade.
This will help the road withstand future debris flows.
Approximately five miles of Highway 1 is closed to all vehicles, pedestrians and bicyclists.
The northern closure is two miles north of Rat Creek at the Lime Creek Bridge, and the southern closure is located at Big Creek Vista Point.
Caltrans says crews will be working long hours with tens of thousands of cubic yards of material, which means rain could cause delays.
This project is estimated to cost $11.5 million, with $5 million in ongoing emergency repairs.
The contractor is Papich Construction of Arroyo Grande.