Here's why BART shut down for hours, and why it has people thinking about the agency's future

San Francisco Chronicle​

09-05-2025

BART had barely restored service, after an hours-long meltdown on Friday, when the politics and damage control began.
'The temporary outage provided a window into what life in the Bay Area will be like without robust BART service,' state Senators Scott Wiener, D-San Francisco, and Jesse Arreguin, D-Berkeley, said in a joint statement to convey the urgency of funding transit. Like other agencies, BART will soon face a deficit of up to $400 million a year, which would almost certainly send the rail system into a death spiral.
But as civic leaders touted the importance of BART, officials at the agency scrambled to reassure the public that their infrastructure is not about to break down. A decade-long project to install a new train control system is currently underway. Engineers say that once it's complete, BART could vastly increase its capacity and become more reliable.
Besides, they say, Friday was an isolated malfunction that no one could have predicted.
Staff at BART, and their political allies, have a somewhat complex message for the public, a dance of eliciting empathy and managing image. BART needs money, but it's not deteriorating. Major revitalization is just around the corner. The service freeze on Friday was an outlier. Spokespeople described the 'root cause' of the outage as minute and specific, akin to a tiny flaw on a piece of connective tissue.
They explained in a statement that two network devices were intermittently failing to communicate. As a result, engineers at the Operations Control Center 'lacked the visibility of the track circuits and the train positions necessary for safe operations.'
When BART engineers detected the glitch on what they said was a 'redundant' section of the network, they disconnected it, enabling passenger service to restart.
Think of it as a large-scale version of your Internet router crashing.
'Everything has to be working perfectly,' for trains to run smoothly and deliver 170,000 commuters throughout the Bay Area, spokesperson Alicia Trost said.
How the public will receive that message depends, in part, on whether BART commuters have memory-holed an uncannily similar outage that occurred in 2019. In that instance, a network switch broke, halting trains for hours on a Saturday morning. At the time, the agency's general manager of operations promised a suite of upgrades to prevent a repeat. Over the next five years BART overhauled its computer hardware and software. The agency also used federal funding to build a network disaster recovery data center.
'Lessons learned' from the 2019 episode helped quickly resolve the situation on Friday, BART spokesperson Alicia Trost said.
Yet the real technology fix — a modern control system to update the 1960s equipment at BART's core — might reach the finish line just as the rail agency enters a financial crisis. The transit agency anticipates a funding gap of $300 to $400 million a year once federal and state emergency funding runs out. It could translate into service cuts so deep that BART would close stations and only run trains once an hour.
If that happens, it would undercut the restoration work that's finally begun, after years of planning and discussion.
Officials at the transit agency acknowledged that quandary as they conducted a post-mortem Friday afternoon, by which point trains were running throughout the Bay Area. Transit activists, meanwhile, gathered at a freeway off-ramp in San Francisco to protest what they see as a dearth of funding, 'which leads directly to the sort of outages BART had this morning,' said one of the organizers, Cyrus Hall.
'This was really a snap decision,' Hall said, adding that he had planned to go rock climbing when a friend called to say BART was out and it was time to make a point.
'We made the signs,' Hall said, 'and we rushed downtown.'
Wiener and Arreguin are pressing for a transit sales tax measure next year that would also include some accountability measures for the agencies. The idea is to deliver consistent service and build public trust. Hours-long breakdowns will neither be routine, nor expected.
'I want to understand what caused (the breakdown), but I also want to understand what does getting around the Bay Area look like without BART,' Wright said. 'Because that's a real question we're having to contend with in the coming year.'
In that sense, Friday served as a harbinger.