The Yuba City bus disaster occurred on May 21, 1976 in Martinez, California. A chartered school bus transporting 52 passengers on an elevated offramp left the roadway, landing on its roof. Of the 52 passengers, 28 students and an adult adviser were killed in the crash. As of 2019, the incident remains the second-worst bus disaster in U.S. history and the deadliest to involve a school bus. It also remains the deadliest highway disaster ever investigated by the National Transportation Safety Board since its creation.
Incident
On May 21, 1976, Yuba City High School chartered a school bus from Student Transportation Lines, Inc. to transport its a cappella choir from Yuba City to Miramonte High School in Orinda for a friendship day involving the choirs of the two schools. The company supplied a Crown bus, dating from 1950. The accident occurred at 10:55 a.m., as the driver took the Marina Vista off-ramp from I-680 southbound from the Benicia–Martinez Bridge. The driver was unfamiliar with this bus, and mistook the low air pressure warning was a warning of low engine oil pressure. Intending to stop for oil, the driver left the freeway at the aforementioned off ramp; the air brake system failed due to lack of air pressure. With no braking capability, the bus struck the mounted bridge rail and left the elevated roadway. After falling 21.6 feet, the bus landed on its roof, crushing it to the base of the window line. Out of 52 passengers on board, twenty-eight students and an adult adviser were killed. All of the surviving passengers were injured, most critically. The driver survived the crash but was seriously hurt.
Investigation
The accident was investigated by the National Transportation Safety Board, which it attributed to the unfamiliarity and inexperience with the driver with the design of the 26 year-old bus and his confusion of oil pressure and air pressure warnings. Other cited factors included proper maintenance and inspection of the compressor drive belt. Several aspects of the road design were cited as contributing factors to the accident, including the curvature of the offramp itself, the signage of the offramp, curb and railing systems.
Memorials
The Yuba City bus disaster was the second-worst bus disaster in U.S. history, exceeded only by the 1963 train-bus collision in Chualar, California which claimed the lives of 32 Mexican farmworkers. In May 1996, on the twentieth anniversary of the accident, a memorial built near the water at the Martinez Marina was dedicated to the victims. Bearing the names of those who died, it was constructed by firefighters who had responded to the accident and their friends and largely funded by them and donations they obtained. On the 35th anniversary of the accident in May 2011, Contra Costa County firefighters dedicated a monument in Yuba City. In 2015, the I-680 freeway off-ramp was replaced with one having a longer and flatter approach.
