Floodwaters from the Pajaro River levee break reached northbound Highway 1 Sunday morning, forcing officials to shut down the highway at 9am.
The northbound lanes of the highway are shut down from Salinas Road to Highway 129.
As of 10:30am, the California Highway Patrol was preparing to shut down the southbound lanes.
There is no timetable for reopening, according to the California Highway Patrol.