- Would knowing the number of stalls available in a parking lot get you off the street any faster?
- If E-Park does work, would you expect the number of cars in Seattle to increase due to experiencing less congestion (i.e. induced demand)?
- If the answer to #2 is “yes”, is encouraging driving ok in this circumstance? Why?
I’ll attempt some non-authoritative guesses to advance a conversation.
Continued beyond the jump…
1.Let’s establish a theme of using some standard economic concepts, with the most fundamental concept being cost. We know there is an actual dollar cost for paying for parking, and there is a time cost to driving around looking for parking; what is less obvious is that there is an “information cost” for finding where garages are and how empty they are. Reducing that information cost for garages could help some drivers park faster. Presumably, the answer to the question is yes.
As an aside, the most tangible and self-aligning of these “costs” is the price signal of dollars. We can guess, then, that just reducing information costs regarding parking probably will not have a muted effect compared to San Francisco’s far more ambitious plan to move street parking prices with demand is based. That plan is based on a clearer economic model and seems to be more consistent with urban values than just advertising parking information
2. Let’s start with the end of the question: the phrase induced demand. This term is thrown a lot in transportation circles, but we must use it carefully. Building a new highway or other transportation corridor that opens up previously “very, very costly” commute patterns has been shown to induce demand, since the new roads just encourage people to move along the highway corridor.
Clearing just some parking congestion downtown should probably not be view through this lens: it is not a dramatic reduction in the cost of driving downtown. Parking is still expensive and it’s still generally not worth going through downtown on the way to another location. Simply eliminating a driver, or ten drivers, from a given road does not “induce” demand, because — for that road to be a desirable corridor — the demand must already exist. And keep in mind, for many drivers, the cost of taking transit is less than driving as it is, and marginal changes won’t significantly alter that dynamic. With that in mind, even slightly reduced congestion downtown does reduce the cost for most of those who had a potential downtown trip and thus, because the demand curve slopes downward, we would expect some more cars in total to use downtown streets.
3. We must decide two things: a) does efficient movement on streets “encourage” driving?, and b) does the total amount of cars using downtown in a day matter? (Is it not “ok”?)
a) So long as government is tasked with operating streets they should probably operate them as reasonably efficient as possible. Efficient operations of streets may reduce the cost of driving compared to leaving those roads in disarray, but I’m skeptical we should be happily shy from reducing the arbitrary costs of driving such as congestion or the inconvenience that comes from information costs. “Encouraging” policies probably look different: cheap street parking costs, a lack of tolls, and building new highways. So, I don’t think the premise of this question is helpful.
b) From a vehicle-miles-traveled perspective and from an environmental perspective, we shouldn’t be so sure. If the effect of the parking program that the average downtown car is traveling fewer miles and idling less looking for parking spots, the mere existence of an additional car on downtown streets at some time during the day may not be a serious problem. But additional cars may mean additional driving outside of downtown, so we can’t be very conclusive in either direction.
So my answer to Matt’s third question is to reject the premise of the question. My conclusion is I see no terrible harm with increasing the ability to traverse downtown with a car, so long as the major feeders into downtown (such as highways) are not expanded and the transit options are still generally lower cost than most driving. And my point, separate from my conclusion, is that just as we should be skeptical of a new highway’s promise to end congestion, we should be skeptical of our own biases.
Still, while the modest policy from SDOT is probably shouldn’t earn too much ire, it probably also doesn’t deserve much praise. A parking model with better price signals, for example, would result both reduce congestion while bringing up fewer pointed questions from car skeptics like Matt.