Getting the Phase II BART Extension Right

There are rumors that the Santa Clara Valley Transportation Authority (VTA) may finally have come to its senses. As previously reported in these pages (See BATWG Newsletter #14), Phase II of the BART extension along Santa Clara Street through downtown San Jose was to require almost 5 miles of tunnel 56 feet in diameter, the height of a five story building. The subway was also to be exceedingly deep, resulting in longer escalators, longer elevators, longer stairways, longer ventilation structures and longer utility runs. According to a VTA presentation made to the BART Board on May 31, 2019, the bottom of the subway was to be 121 feet below grade, the height of an eleven story building. Needless to add this design added greatly to the project cost.

But the situation could be brightening. With a small section of cut-and-cover construction at the two downtown stations the size of the subway could reduced enough to avoid having to haul away an extra 1,400,000 cubic yards of spoil. It would also significantly reduce both the thickness of the concrete tunnel lining and the depth of the subway. It is to be hoped that common sense will eventually prevail in San Jose.

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