The CHP says alcohol is to blame for a two-vehicle accident on Highway 99E in Los Molinos.
Investigators say 31-year-old Marla Miller of Chico was intoxicated while driving her Ford Focus and missed a right turn in the road south of 61st Avenue around 10:45 p.m. Tuesday.
She crossed over into the northbound lane and collided with a guard rail, eventually hitting part of a bridge.
After, a passers-by from another car got out to flag down approaching traffic to avoid another accident.
But that's when 52-year-old Jeffery Jones crashed his semi truck, trying to avoid the pedestrian in the road.
Miller suffered major injuries and was taken to Enloe Medical Center.
No one else was injured.