Two vehicles collided on Highway 101 near Cotati Friday morning, causing minor injuries and blocking one lane, according to the CHP.
Two people were taken to Santa Rosa Memorial Hospital but injuries appeared to be minor.
The vehicles collided just before 11 a.m. on southbound Highway 101, just north of the Highway 116 exit as one vehicle rear-ended the other.
The slow lane was blocked from the crash and a small amount of motor oil spilled.
Initial reports said it had gotten into a storm drain, but Caltrans workers cleaned it up prior to it causing a problem, the CHP said.