Highway 1 at Rat Creek in the Big Sur area reopened to traffic Friday.
It's been closed since a debris flow washed away about 150 feet of the roadway during a heavy rainstorm on January 28.
Road construction crews rebuilt the section of highway by filling the canyon with 45,000 cubic yards of dirt in a triangle shape and laying a new roadway on top.
The reopening happened one week earlier than previously announced and nearly two months earlier than the original target date; however, Caltrans says some construction activities will continue even after the highway is open.
That includes installation of a permanent guardrail, construction of headwalls at the culvert inlets, final grading features, and placement of erosion control measures on both sides of the roadway.
Crews will also need to tunnel underneath the new road to install a 10-foot diameter, one-inch thick steel pipe culvert from the canyon to the ocean.
Caltrans says this will improve water flow during future storms. Three smaller culverts have already been installed closer to the grade of the highway.
Drivers may experience traffic control and approximately 10-minute delays while this road work continues over the next few months.
Caltrans says the entire project cost about $11.5 million. The project contractor is Papich Construction of Arroyo Grande.
KSBY News reporter Alexa Bertola is covering the re-opening of the highway and will have the full story on KSBY News at 5 and 6 p.m.