I had dinner last Friday with friends and friends of friends, two of whom happened to work at the Metropolitan Transportation Commission ("the transportation planning, financing, and coordinating agency for the nine-county San Francisco Bay Area"). Given my frequent advocacy of congestion pricing, this was sure to lead to some interesting conversation (more accurately, interesting for me, excruciatingly boring for everyone else).
I was happily surprised to find that they were both staunch supporters of congestion pricing, although one of them insisted that it be real-time, which I agree is very important. They gave a couple of reasons for why congestion pricing has been slow going:
1) I was the first person that either of them had ever met who is in favor of congestion pricing. Everyone has an opinion on the work they do, but for the most part their questions are along the lines of "Where's my highway? Why haven't you built that fourth lane yet?" and so on and so forth.
2) There was some talk at one point of instituting congestion pricing on the Bay Bridge, but it was killed by Caltrans, who was afraid that people would work so hard to avoid the higher tolls that revenue would fall. This, of course, makes absolutely no sense. It would be possible to make the change revenue neutral - this would entail lowering the price in off hours to compensate for the increated revenue during peak times - but there's no way it would ever reduce revenue.
Traffic systems break down when the average speed is under 40 MPH or so. Below that speed, throughput actually declines. This is hard to understand intuitively, but what it means is that if you set the price to maintain a speed of 40MPH or faster, there will actually be more cars crossing the bridge during peak periods, which means revenue will increase in this period due both to higher tolls and more cars.
There will of course be people who decide not to drive during peak periods. These people will choose one of three main alternatives:
1) They will drive at another time when the price is lower. In this situation, Caltrans still gets a toll from them, as high as the current standard toll if necessary.
2) They will take public transportation. This is obviously a good outcome for both Caltrans and society.
3) They will cancel their trip. This is also a good outcome for society, even if it reduces Caltrans revenue (which, regardless, will still be greater than before) - if the market price for traveling makes certain types of travel uneconomical, then businesses that rely on that travel should not exist - they are currently subsidized by society, by the other drivers in lost time, and by the environment through the ncreased environmental harm of traffic congestion.
Studies have shown that congestion pricing lanes are not used solely by the rich, but are in fact used by people of all income levels, generally when late for work or to an appointment. Congestion pricing allows parents to avoid late fees for childcare and plumbers to get one last job in. And it enables high-speed bus service to actually be high speed, which is a big benefit for low income citizens who don't own cars.