The key economic concept here is "public good,” that is any good that is non-rivaled (no one person’s use detracts significantly from another person’s use) and non-excludable (no groups are excluded from using the good). Without getting into the details, it’s pretty clear to me that the early model of multiple-use streets meets the definition of public good, while the latter car-dominated model does not.
Generally it makes more sense to regulate use of a non-public good through a market-based approach, otherwise you end up in a tragedy of the commons scenario – endless traffic congestion, externalities from the emissions and noise, etc. Brookings fellow Anthony Downs explains the rationale for freeway pricing pretty succinctly in Still Stuck in Traffic:
“Access to freeway space during peak hours is a desirable good definitely in limited supply. When it is free, the number of drivers who want it greatly exceeds the available space on the roads involved during peak hours. If that space is handed out on a first-come, first-served basis, lines will form until space is fully occupied. That equals traffic congestion … The alternative of charging a “market clearing” price seems a lot more sensible. By setting the price appropriately, this approach can reduce the number of people willing to pay that price down to the level at which they can all move rapidly on the road.”I mention all of this to bring up a dilemma I’m puzzling over:
Road pricing makes sense to me, given that our roads are now essentially functioning as private space yet are still, at least partially, paid for with public funds. But won’t a full-fledged pricing system amount to the consummation of the automobile’s victory over this contested space? Is this throwing in the towel?
It seems that there are a few ways to slice this. Some roads, especially limited access highways, can be treated as private roadways, that is government-owned yet priced like a market, and other more local streets can be treated like public space. Or it can be sliced by mode, rather than spatially. Cars on all roads could be priced, since they are the ones causing rivalry and exclusion after all, while other modes could be treated as public amenities.
These hybrid strategies seem great in theory, but they may be hard for us to grapple with culturally. The more drivers believe they are paying for the roads, the more they will feel justified in not having anyone in their way. The alternative for local roads is the Dutch "Woonerf" strategy: all modes are mixed together in a truly public fashion, and motorists are not given any special rights. They have to cautiously navigate their way through the crowds like everyone else.
Are these conceptions of space mutually exclusive? Can they be mingled together or subject to local variation? Would that be too confusing?
I know some people reading have thought more about this than I have. Assuming I haven't shaken you off with my long-winded speculations, please help me out here!