A FlixBus carrying passengers on Interstate 5 collided with a semi-truck yesterday evening in San Diego County, sending a dozen people to area hospitals with injuries ranging from minor to moderate. The California Highway Patrol responded to the crash at 5:24 p.m. on southbound I-5 near the San Elijo viewpoint in Encinitas, in the middle of the evening commute.
None of the injuries were life-threatening, according to CHP. As reported by Fox 5 San Diego, the crash involved a FlixBus passenger bus and a semi-truck, and injured passengers were taken to the hospital following the collision. FlixBus is a long-distance and intercity service that ferries passengers between cities across California, and the exact location places the wreck within a stretch of I-5 that has seen serious commercial vehicle incidents before — as detailed further below.
CHP Leads Investigation, Reminds Drivers to Keep Their Distance
The California Highway Patrol is investigating the cause of the crash. As the sole agency with jurisdiction over enforcement and investigations on state freeways like I-5, CHP is expected to determine what led to the collision, according to City of San Diego open data documentation, which explains that local police departments handle only street-level crashes while the highway patrol retains authority over freeway incidents.
In the wake of the crash, CHP reminded drivers to stay alert, avoid distractions and maintain a safe following distance — guidance the agency stressed is especially important when traveling near large commercial vehicles like buses and semi-trucks. That advice lines up with state law: under California Vehicle Code Section 21703, drivers are barred from following another vehicle more closely than is reasonable and prudent, with citations carrying a base fine of $238 and total court costs that can reach $490 to $550, plus a point on the driver's record, according to Cron Israels and Stark.
Why Following Distance Matters So Much for Big Rigs
The physics behind that warning are stark. Per guidance from the California DMV, a standard passenger vehicle traveling at 55 mph needs roughly 300 feet to stop completely, while a large commercial vehicle or loaded truck moving at the same speed can require 400 feet or more. Commercial buses and trucks with three or more axles are also legally capped at 55 mph on California freeways under Vehicle Code Section 22406, regardless of the higher speed limits posted for passenger cars.
Federal safety standards go further still. The Federal Motor Carrier Safety Administration recommends that commercial drivers maintain a following distance of one second for every 10 feet of vehicle length, which works out to a 7-to-8-second gap at freeway speeds for full-sized tractor-trailers. Whether following distance, driver fatigue or mechanical failure played any role in Monday's crash has not been determined, and CHP has not indicated whether citations will follow its investigation.
A Corridor With a History of Truck Trouble
This is not the first time this stretch of I-5 in Encinitas has dealt with a major commercial vehicle incident. In December, a pre-dawn big rig fire near Birmingham Drive forced a 12-hour closure of multiple lanes and off-ramps, according to the Times of San Diego. Monday's crash also landed squarely within the riskiest window for regional traffic — crash data compiled from regional reports shows the peak hour for collisions in San Diego County falls between 5 and 6 p.m., the same window in which CHP responded to this incident.
The county sees a high volume of crashes overall. San Diego recorded more than 23,000 total traffic collisions across its highway and regional road network in 2023, according to the San Diego Association of Governments. It remains unclear which vehicle struck the other in Monday's crash, and it is not yet known which company was physically operating the bus, since FlixBus functions primarily as a digital booking platform that contracts actual driving operations out to independent charter bus companies rather than operating all of its own vehicles.
