Talk of 2nd BART Transbay Tube Resurfaces

 SAN FRANCISCO (AP) - With the San Francisco Bay Area economy booming, a plan to build a second tube for BART trains under San Francisco Bay is getting renewed attention.
 
San Francisco Mayor Ed Lee said last month he planned to begin a regional conversation about another Transbay Tube, and an Alameda official said at a recent workshop he was eager to work with BART on a new tube to bring the transit service to his island city, the San Francisco Chronicle reported on Sunday.

BART trains currently only have one tunnel under the bay, creating delays when a train stalls or other problems arise. A second tube would allow BART to offer 24-hour service and increase the system's capacity, supporters tell the Chronicle (http://bit.ly/1LzNY8r ).
 
"Having a second BART tube isn't optional,'' said San Francisco Supervisor Scott Wiener, who is also a member of the regional Metropolitan Transportation Commission. "We have to do this. The tube is the BART system, and it's basically full.''
 
Still, almost no one expects a second tube to become a reality anytime soon. The cost - estimated to be as high as $12 billion - is one major obstacle. A second tube would also have to satisfy environmental concerns.
 
"If anyone wants to know how long it will take and how complicated it will be, think about the eastern span of the Bay Bridge or high-speed rail...'' said Martin Wachs, a retired University of California, Berkeley planning professor.
 
BART right now is looking at other ways to increase capacity and deal with overcrowding, spokeswoman Alicia Trost said. Those include running longer trains or extra service, expanding the fleet and replacing the train control system to run trains closer together.
 
A study of a new tube isn't likely to start until at least 2017, the Chronicle reported.