SACRAMENTO COUNTY -- An overturned truck shut down northbound Highway 99 Monday for around three hours.
The truck was carrying 40,000 pounds of large rocks or boulders, which spilled onto the road just north of Galt around 1:15 p.m.
According to the CHP, the truck clipped part of a Caltrans message board over the highway, causing the massive sign to fall.
Lanes south of Twin Cities Road reopened around 4:30 p.m.
The driver was uninjured in the crash.