That's the social cost that Charles Kamonoff, an NYC environmental/transportation analysist, believes each driver who enters Manhattan's central business district imposes on other drivers. Via Felix Salmon:
After crunching the numbers, he calculates that on a weekday, the average car driven into Manhattan south of 60th Street causes a total of 3.26 hours of delays to everybody else. (At weekends, the equivalent number is just over 2 hours.) No one car is likely to suffer excess delays of more than a few seconds, of course, but if you add up all those seconds for the thousands of affected cars and trucks, it comes to a significant amount of time.
Many of those hours are very valuable things, especially when you consider big trucks, staffed with two or three professionals, just idling in traffic. Komanoff calculates (check out the “Value of Time” tab) that the average vehicle has 1.97 people in it, and that the average value of an hour of saved vehicle time south of 60th Street in Manhattan on a weekday is $48.89. Which means, basically, that driving a car into Manhattan on a weekday causes about $160 of negative externalities to everybody else.
I can't vouch for Komanoff's numbers or his methodology. Given the sheer complexity of the traffic dynamics in Manhattan -- which are much more complicated than the traffic dynamics of a single highway -- I would treat his estimate skeptically.
That said, his estimate doesn't seem outrageously high to me. The basic point is sound: we severely underestimate how many people we delay when we enter a congested network of roads. If you've ever tried to make the trip crosstown Manhattan in the middle of the day, you understand just how much delay one driver can cause.
Komanoff recommends congestion pricing. A good idea. But he also proposes making buses free, which is a bad idea (and one floated in Austin occasionally).
One problem is that a free bus would be a magnet for the homeless looking for a cool place to hang out. That sounds callous, I know, and perhaps it is, but in that case you'd never see a large switch from cars to buses, so what would be the point?
The other problem is that both bus and rail can be congested, too. If you've ever taken a packed No. 3 around ACL, you understand this perfectly well. There is a cost to standing up on a jerky bus for 20 minutes, squeezed in among a bunch of strangers who may or may not practice good hygiene. This is a genuine cost of congestion. In fact, it is probably too high a cost for most of the drivers around here, who would much rather be stuck in traffic in a cool, comfortable car.
If we price roads but not buses or trains, then the buses or trains will be too crowded (at least in Manhattan and DC, if not in Austin) and we simply will have shifted the cost of externalities from drivers to bus and train riders. This certainly does not mean that buses and trains must pay their own way. But it does mean pricing them with the interests of both drivers and non-drivers in mind.
