Some transportation experts argue that even bolder action is necessary. To encourage car-pooling they have called for banning vehicles with fewer than three people from the Williamsburg Bridge for longer than just rush hours as the city envisions and extending the ban to other bridges. And 14th Street, they say, should be restricted primarily to buses 24 hours a day to make it easier on subway riders.
“A lot of people don’t commute 9 to 5 hours,” said Kate Slevin, the vice president of state programs and advocacy at the Regional Plan Association, an urban research group. “A lot of people are traveling down 14th Street all times of the day. The worry here is you’re just going to have an inability to get around.”
For now, the biggest worry on all sides is preparing for the unknown.
“It might look all right on a computer simulation,” said City Councilwoman Margaret Chin, who represents Chinatown. “But in real life, I just can’t imagine it.”
14th Street: Nation’s Busiest Bus Route
The nucleus of the city and the M.T.A.’s plan is 14th Street, which stretches from the East River to the Hudson River. During the morning and evening rush between Third Avenue and Ninth Avenue, it will be limited to buses with the exception of some vehicles like delivery trucks.
The city has a goal of ensuring that buses can cross the bus corridor along 14th Street in 20 minutes, a speed rate of over 6.5 miles per hour and over 40 percent faster than buses there travel now. But some transit experts are dubious, believing that 14th Street “will saturate with buses,” said Annie Weinstock, the president of BRT International, a company that plans and designs bus rapid transit systems and that helped produce an alternate plan for 14th Street. “Buses will queue up behind one another and become a bus parking lot.”
Ms. Trottenberg said the plan for 14th Street was flexible. “If we don’t get it right from the start we can adjust,’’ she said.
Transit experts have pushed for buses to be free to speed loading and prevent gridlock. “The only way we are going to get near the capacity that the M.T.A. thinks will shift on to buses is if we do everything we can to get people onto those buses as fast as we can,” said Nick Sifuentes, executive director of the Tri-State Transportation Campaign, an advocacy group.
A spokesman for the M.T.A., Jon Weinstein, said the agency had not made any final decisions about fares.
Businesses have already begun making plans for the shutdown, including shifting deliveries to overnight to avoid the crush, said Jennifer Falk, executive director of the Union Square Partnership, the business improvement district for the area. On the other hand, some retailers are looking forward to the flood of new commuters. “There are tens of thousands of people who will experience the ground floor retail on 14th Street who would never come above ground before,” Ms. Falk said.