A woman in her 30s died early Sunday after her car struck a boulder in the median of southbound Interstate 280 in the unincorporated Hillsborough area of San Mateo County. Her vehicle was later found in a ditch, according to the California Highway Patrol and NBC Bay Area.
The crash happened around 2 a.m. in the center median of the southbound lanes, south of the Black Mountain Road/Hayne Road exit, according to NBC Bay Area. The woman was the only occupant of a black Volkswagen Tiguan at the time.
Officers Missed the Wreck in the Dark
CHP Officer Sophie Lu said officers responded to a call at about 2 a.m. but initially found no evidence of a collision in the darkness. Additional calls followed, and the vehicle was located in a ditch in the center median at about 7:30 a.m., according to NBC Bay Area.
The available report does not explain what occurred between the initial response and the vehicle's discovery. CHP has not publicly detailed the intervening search or the roadway conditions that may have affected visibility.
What Caltrans guidance says about freeway safety
Caltrans' 2025 Traffic Safety Systems Manual says emergency passageways should be located to provide adequate visibility and stopping sight distance to and from the opening along a freeway. That general guidance does not establish the conditions at this crash site or explain whether any specific median feature contributed to the collision.
Woman's Identity Not Yet Released
The California Highway Patrol has said only that the driver was a woman in her 30s; her name has not been released. The exact cause of the crash, along with any details about the boulder or roadway conditions in the median, has not been disclosed beyond what CHP has reported so far.
