The fatal stabbing on BART last week has the transit system’s leaders scrambling to speed up the installation of jump-proof fare gates — if they can find the money, that is.

But even then, it will be at least three years before the gates start going in, and only at “high priority” stations.

“We are looking at moving money from other projects or reprioritizing projects to get the necessary funding to get started,” BART General Manager Robert Powers said Friday. “Right now the priority is to move forward as fast as possible.”

BART board President Bevan Dufty agreed, saying, “I think the public and the events of this past week has moved installing the new fare gates to the front of the line.”

That wasn’t the case a week ago, when BART officials said funds were all tied up on other projects long in the pipeline, like new train cars, station makeovers and new control systems. At that time, BART officials said it would take four years before the new gates would be installed in most BART stations.

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After years of public outcry about safety on its trains, BART directors voted unanimously in September to replace the system’s 600 easy to pry open — or jump over — fare gates with new, taller, saloon-like door gates that will make it more difficult to enter without having paid the fare.

BART estimates it loses $25 million to $30 million a year to fare evaders, who often exhibit the bad, sometimes dangerous, behavior that makes riders feel unsafe.

“The impact of homelessness and mental illness being seen on the trains is all tied together with fare evasion,” Director Robert Raburn said.

And while the directors gave the OK for new gates, they didn’t set a specific timeline or approve any money for the project.

Instead, they directed BART staff to find the money.

It turned out, however, that the $3.5 billion in Measure RR BART bond funds that voters approved three years ago had already been been committed to 80 other projects, such as buying a new train control system and upgrading power supply systems to increase the number of rush-hour trains.

“It has all been programmed,” Powers said of that money two weeks ago when asked about the new gates.

Powers said it could take up to a year and might require passing a new sales tax for BART to find the $150 million for the gates.

Once the money materializes, Powers estimated it would take “four to four and a half years” for there to be a “substantial completion” of new gates.

That all changed last week, when a BART rider was fatally stabbed by a “walkaway” patient from San Leandro Hospital listed as “at risk” who allegedly stabbed to death Oliver “Tyrone” Williams in a fight that started when the man tired to steal shoes off another man sleeping on the train.

Powers said he has been meeting with staff to “immediately begin looking to cobble together” the funds from as many pots as possible.

One prospect would be to use BART’s $90 million share of voter-approved Alameda County Measure BB tax money earmarked for station modernization to begin hardening the 22 stations in Alameda County.

That still leaves 26 stations, which may mean redirecting RR money for station modernization as well.

“We are looking at projects to see what elements are critical and at the overall costs of projects to see if we can use some of the money for the fare gates,” Powers said.

Powers has also directed staff to begin planning for the gates to speed up installation once the money is shifted.

It’s a policy shift that has long been advocated by Director Debora Allen.

“Station hardening is still not a high enough priority for some directors, but I am glad to see our general manager now move it to the top of priorities,” Allen said.

Powers said the goals is to start phasing in the fare gates within three years at “high priority” stations.

The stations will be selected based on frontline staff and BART police recommendations and where high rates of fare evasion and crimes are ongoing problems.

“The board was unanimous in wanting to see the fare gates change,” Dufty said. “The events of this week put this at the head of the line.”

And while the gates are now at the front of the line, that line’s still three years long.

Early day: Whatever new Muni chief Jeffrey Tumlin lacks in experience, he appears ready to make up with enthusiasm.

Tumlin doesn’t officially start his new job until Dec. 16, but when a text came in from Muni on Monday morning informing him that a “traction power failure” had shut down the Sunset Tunnel, making a bus bridge necessary to handle the commute, Tumlin was out the door and on his bike.

“It was just a couple of minutes to the Castro Street Station,” where the buses were starting to line up, he said.

He first found the station agent, who said it was unclear which buses were going where. His next stop was the buses to find out where people should line up, then back to the station agent to give her the information.

Together, Tumlin and the agent began assisting commuters.

“People were grateful to have clear information,” he said.

Tumlin’s rush to assist was not lost on City Hall, where Room 200 — the mayor’s office — had been upset with former Muni chief Ed Reiskin’s more laid-back style.

San Francisco Chronicle columnist Phil Matier appears Sundays and Wednesdays. Matier can be seen on the KGO-TV morning and evening news and can also be heard on KCBS radio Monday through Friday at 7:50 a.m. and 5:50 p.m. Got a tip? Call 415-777-8815, or email pmatier@sfchronicle.com. Twitter: @philmatier