Brookings responds to criticism of their access to transit study
Last week, the Brookings Institution published a report, Missed Opportunity: Transit and Jobs in Metropolitan America, that was widely publicized in the media. Nate Silver of the 538 blog wrote some criticism of it, which was published in his blog on the New York Times website. I wrote about it on Sunday.
Two of the report’s authors, Alan Berube and Rob Puentes, responded, in the entry "Maintenance of Silver's Transit Line" (which I have to say is a forced joke-type headline referring to the development of the so-called Silver Line subway service in Fairfax and Loudoun Counties in Northern Virginia).
From the entry:
Silver’s central criticism seems to be that ranking cities’ transit systems based on how many people have access to transit, and how many jobs transit can deliver potential commuters to, ignores a much larger, more important question--is transit a better commuting option than driving a car? He probes the latest Census Bureau data to show that relatively few workers commute via transit in some of the highest-ranking metro areas on our list. How good can these systems be, he asks, if no one is getting out of their cars to use them?
We agree that this is not a great way to rank transit systems … but our report didn’t rank transit systems. It ranked metropolitan areas on how well their households and jobs were connected via transit.
• the percentage of a region's jobs that are reachable via transit within 90 minutes;
• the percentage of working-age residents living near a transit stop;
• the average wait time for a bus during rush hour;
what also matters is what percentage of people actually use transit and why or why not. As I mentioned in the entry, what this ends up being is more of a measure of relative compactness of a region.
Although it would be useful to study sub-districts within regions and determine why people use transit or not. But we already do this (they are called "transportation analysis zones") and we know why this is so: the nature of the routes; distance to work from home; dispersal-deconcentration of jobs within a region; and lack of relatively direct transit vehicle routing (most regional transit systems key on the center city, whereas jobs have become much more dispersed within a region and increasingly located farther and farther from the core).
The big problem is that the more that places are dispersed (polycentric land use) the less possible it is for transit to service these areas efficiently, because transit service is best provided when serving relatively compact (monocentric) places (which is the basis of the arguments laid out in Belmont's Cities in Full).
What we need to be doing is changing our land use planning paradigm, to link land use decision making with transportation planning and capacity of existing infrastructure. That makes transit more efficient and effective, albeit less comfortable because it serves more people (e.g., San Francisco's MUNI system).
The more we put high traffic generating uses in places where cars are the most likely to be used mobility option, the more that the network is stressed.
The suggestion of putting a Wegmans on Georgia Avenue NW, in an area without subway service (although the Takoma Metro is about 1 mile away), for a use that is likely to generate mostly car trips--although it wouldn't if it were placed at a Metro station, complemented by the provision of delivery services--is a perfect example of how not to do land use planning.
Labels: transportation planning
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