Yuba City bus disaster

The Yuba City bus disaster occurred on May 21, 1976 in Martinez, California. A 1950 Crown bus operated by Student Transportation Lines, Inc. had been chartered to carry the Yuba City High School a cappella choir from Yuba City to Miramonte High School in Orinda for a friendship day involving the choirs of the two schools. The accident occurred at 10:55 a.m., as the driver took the Marina Vista (exit 56) off-ramp from I-680 southbound from the Benicia–Martinez Bridge. The driver was unfamiliar with this bus, and mistakenly thought the low air pressure warning (for the air brakes) was a warning of low engine oil pressure. The driver left the freeway at the aforementioned off ramp, and the brakes failed due to lack of air pressure. The bus struck and mounted the bridge rail and left the elevated roadway, falling 21.6 feet. It landed upside down and crushed the roof to the bottom of the bus windows. 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.

The accident was investigated by the National Transportation Safety Board and attributed to the failure of a compressor drive belt supplying air to the brakes on the aging vehicle and inexperience and negligence on the part of the bus driver. Various aspects of the ramp itself, including the severe radius of the curvature of the ramp and lack of warning signs, were also cited as contributing factors. The NTSB also noted that the accident was at that time the worst school bus crash and the worst highway disaster since the agency was created in 1967.

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.

As of May 2012, the Yuba City bus disaster was the second-worst bus disaster in U.S. history, exceeded only by a 1963 train-bus collision in Chualar, California which claimed the lives of 32 Mexican farmworkers.

The ramp was replaced with one having a longer and flatter approach in 2015.