Decisions still to be made on downtown SF rail extension tunnel

SAN FRANCISCO (KGO) -- Come this summer, the Transbay Transit Center will be bustling with activity. That's when phase one of the mammoth project will be completed. Think buses for a moment. Muni buses, AC Transit, Golden Gate Transit, Sam Trans and Greyhound buses will deliver and pick up thousands of people.

But today at the Transbay Joint Powers Authority Board of Directors meeting we found out that phase one was supposed to be done by December of last year. Because it wasn't, an additional 2.5 million will now be spent to oversee its completion.

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"A year, six months to close out the contract and six months to address any potential claims we have with the contractor," explained Mark Zabaneh, the executive director of the Joint Powers Authority.

Then there's Phase Two, the 1.3 mile-long downtown rail extension tunnel taking Caltrain and high-speed rail all the way to the Transbay Transit Center.

According to Zabanehm the completion date for that project is expected to be as early as 2029.

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Here's what needs to happen to meet that deadline. What has yet to be decided is the route Caltrain and high speed rail will take once it enters San Francisco, The Mission Bay alignment or the Pennsylvania Avenue Alignment.

The Mission Bay alignment would go past the Warriors arena, and AT&T Park onto 2nd street and ending up at the transit center. The Pennsylvania Avenue alignment would go past the Potrero Hill neighborhood, past China Basin and the existing 4th and King streets train yard, making a left on 2nd Street and finally to the transit center.

The selection will depend on the cost of each alignment. In the end it will be city hall and its supervisors who will decide which will better serve San Francisco.

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