Caltrain is optimistic about AI technology

The Burlingame crossing tends to see a high rate of vehicle collisions, as two closely situated traffic signals on either side of the tracks on Broadway are in many cases insufficiently timed, causing traffic congestion to build in between the lights, including on a portion of the train track. But the Palo Alto crossing not only sees vehicle collisions, but it also has a higher rate of individuals who have died on the tracks, mostly from suicide. Both were factors in the decision to implement the technology at the crossing.

So far, the results are promising, Chief Safety Officer Mike Meader said. Initial data showed that about three times a week, cars would often turn onto the train tracks, especially at night, thinking they were the nearby parallel street. Since then, the transit agency added several safety markers to the tracks, including markers with red lights and flexible plastic poles for delineation.

“It helped us understand that from watching the video and getting detection … that vehicles attempted to turn off the roadway and onto the tracks at a much higher rate than we expected,” Meader said. “They managed to get themselves back on the roadway, but we wouldn’t have known that without this technology.”

Only two other rail agencies use RailSentry in similar ways, both of them in Texas, he said. The technology uses machine learning to learn what the behavior of vehicles, individuals and pedestrians should look like at a particular intersection. Once a change is detected — usually by Caltrain-developed settings — RailSentry’s monitoring center is alerted, which then notifies Caltrain dispatch.

David Canepa, Caltrain board member and president of the San Mateo County Board of Supervisors, said the improvements are sorely needed, especially as they come at the fraction of the cost of grade separations.

“This could help us really make an impact in saving lives and at the same time doing it in a way that could be very cost efficient,” Canepa said. “We’re in an environment where transit is on the verge of failure so we need to make sure that when AI technologies come out, we embrace it.”

A grade separation at Broadway has been discussed for years and recently, Caltrain announced the original project plans are expected to cost about $889 million, more than double the initial $316 million estimate just a few years ago. The costs to implement RailSentry and the subsequent safety markers was just under $300,000 at the Broadway crossing.

The agency is also facing a significant structural deficit. By July 2026, the average annual deficit will be at least $75 million, according to January estimates.

Burlingame Mayor Peter Stevenson said he feels the technology is a beneficial short-term solution, though the impact is still to be determined.

“On the surface it sounds good, but I think it’s too early to make conclusions about the data,” Stevenson said. “When you contrast it to grade separation, which is a complete elimination of the risks … this is somewhat of an interim solution for the most part, so we want to keep studying what the data shows.”