Caltrans announced the closure is for crews to install precast girders for the Cottonwood Creek Replacement Project.
Northbound Highway 99 at Avenue 12 will be closed only during the overnight hours Monday, August 28 through Wednesday, August 30.
Closures are scheduled from 10:30 p.m. until 4:30 a.m. the following morning.
Caltrans says drivers will be escorted off the highway at the Avenue 12 off-ramp and then back onto the highway using the northbound Avenue 12 on-ramp.
There will be flaggers to guide drivers through the detour.