"It's just a case of bridge shopping," explained Sam Schwartz, a traffic expert and former city transportation commissioner.
Schwartz argued that the numbers provide further proof of the need for congestion pricing, where every route into Manhattan would carry a price tag.
"It's really very bad for the environment," he said of the drivers roaming around seeking cheaper alternatives.
"They're polluting a lot, driving extra miles, using more gasoline."
City Councilman James Vacca (D-Bronx), a strong opponent of congestion fees, reached the opposite conclusion.
"We may be reaching the point of diminishing returns with the constant toll and fare increases," Vacca said. "If they keep raising it further, I'm worried about the impact on jobs. The reality is, some people do have to take their cars to work."
Overall, traffic into and out of Manhattan was relatively flat between 2008 and 2009, dropping by a thin 0.2 percent, from 1,830,907 vehicles to 1,828,065.
Read more: http://www.nypost.com/p/news/local/city_drivers_taking_bridge_to_free_RoACgqCcwqRGun3810zFrJ#ixzz1S6nbzNtI
Needless to say, I'm with "Gridlock" Sam on this issue. Councilmember Vacca is right that some of his constituents have to drive to work, but they are likely driving within the Bronx or to nearby counties rather than lower Manhattan. I would like to know how much extra driving people are doing to avoid tolls. Are they willing to drive 10 extra minutes to avoid about $5 in tolls? Five extra minutes? What are the drivers' values of time? My guess based some work I am doing on taxi travel between Manhattan and LaGuardia airport is that drivers who avoid toll bridges are making a rational and justified decision unless their value of time is extremely high (in the neighborhood of $150 per hour). There really ought to be tolls on all bridges and tunnels into and out of Manhattan. East River tolls could generate nearly $1 billion annually and be much simpler to sell and explain than congestion pricing.
Here is a brief history from the NY Times of why the East River has so few tolls.