A passenger died Friday afternoon after the sedan they were riding in collided with a dump truck on Mountain House Road, north of West Grant Line Road, in far-east Alameda County near the unincorporated community of Mountain House. The California Highway Patrol said a southbound Freightliner tractor pulling two end-dump trailers and a northbound Honda Civic collided broadside within the southbound lane shortly after noon on September 25, 2026. The Honda sustained catastrophic damage, and the passenger was fatally injured. Mountain House Road was shut down in both directions while investigators worked the scene, and both drivers stayed at the scene and cooperated with CHP; alcohol is not believed to have been a factor.
According to Pleasanton Weekly, CHP officials said the cause of the crash remains under investigation and the identities of the drivers and the deceased passenger have not yet been released. CBS News San Francisco reported that Alameda County Fire and Livermore-Pleasanton Fire crews also responded to help clear the scene. Anyone with information about the crash is asked to call CHP’s Dublin office at 925-828-0466 and ask for Officer Hartman or Officer Purl. The investigation into what caused the truck and sedan to collide is ongoing.
A woman died Friday afternoon after the sedan she was riding in collided with a dump truck on Mountain House Road near Tracy, California. The crash happened around 12:04 p.m. on September 25, 2026, on Mountain House Road north of Grant Line Road, between Tracy and Livermore in Alameda County. The woman was ejected from the sedan and died at the scene. Mountain House Road was shut down in both directions for several hours while crews investigated.
According to CBS News, California Highway Patrol units, along with Alameda County Fire and Livermore-Pleasanton Fire crews, responded to the crash shortly after noon. KRON4 reported that the roadway near I-580 had no estimated reopening time in the hours immediately following the collision. The cause of the crash remains under investigation, and authorities have not released the names of those involved.

