Quote Originally Posted by GGT View Post
wiggin, does the Region still have those coin-toss tolls between Indiana/Illinois/Wisconsin highways? Last time I drove those routes I was a passenger and didn't pay any attention. It used to be a dime. I thought the purpose was to pay for road maintenance and repair....not to reduce congestion.
Yes, the Tri-state tollway has tolls, but most of the expressways in the Chicago area (including the Kennedy/Dan Ryan and LSD which get VERY congested) don't.

Quote Originally Posted by Wraith View Post
And if enough people do it, it creates congestion elsewhere. If we move to tolls as a major funding tool, prices would probably wind up fairly high, increasing the incentive to move around congestion spots. You can set up tolls in these new areas too, and good times will be had chasing the dancing high-traffic areas until we wind up with tolls collected everywhere, and all the attendant higher traffic pattern implications (people who pay cash to avoid privacy violations screw things up the worst). Khen raises good points. I think I'm souring on the idea.
There are dynamic pricing strategies to keep traffic at a reasonable level (i.e. to reduce congestion just enough at a given time to collect revenues without sending people en masse to other routes). There's also the aforementioned 'express lanes' that encourage either HOVs, buses, or a high, dynamic toll. This has been successfully piloted in a number of places.

Furthermore, people won't go indefinitely out of their way to avoid tolls - there are generally only a few logical routes from one place to another.

Think of this as a mismatch between supply and demand. There's a limited amount of convenient infrastructure to get from point A to point B. The number of people who want to use that infrastructure is higher than the infrastructure can really handle, but the infrastructure is provided essentially free on a marginal cost basis. This causes overconsumption. Increasing the marginal cost of travel on overloaded roads reduces demand by a variety of avoidance behaviors, and brings in revenue that can be used to upgrade the overall throughput from point A to point B to match equilibrium demand levels.

A classic example is free (or very cheap) street parking in American cities. When prices were jacked up to meet actual demand for parking spaces, people made other arrangements rather than pay the ridiculously high price. This has a lot of positive benefits - it brings in revenues that can be used to alleviate parking or other congestion/infrastructure problems (or subsidize public transit, which effectively alleviates parking pressure). It matches people who get the highest marginal utility out of a parking space with the space (when previously it was essentially a lottery process rather than a pricing process). It reduces congestion due to people looking for spots.

The same basic logic works for any congestion pricing.