An overturned big-rig closed both directions of state Highway 121 in unincorporated Napa County on Monday afternoon, California Highway Patrol officials said.
The crash was reported at 3:35 p.m. at Highway 121 just north of Wooden Valley Road.
A big-rig carrying 20 tons of dirt overturned, CHP officials said.
Napa County sheriff's officials said Highway 121 will be closed until about 6 or 7 p.m. and they're asking drivers to use other routes.
A Sig-alert was issued at 4:01 p.m. because of the closure.