Streetsblog Capitol Hill highlighted a very nice FTA report that tracks urban transit emissions. A pdf of this report appears here.
As I have ranted before here, we have to know ridership in order to make claims about emissions benefits. This graphic, taken from the report, does a good job of showing us this effect. We’d be better off filling up cars on the road than we are running underutilized trains. Now, this is a much different story if we are getting people to use the trains. This is why a reasonable accuracy in ridership forecasts matters. I’m not asking for perfection; I’m asking for an honest assessment of how many people we’re building something for so that we can fairly assess what we are doing here.
The other possible way of changing this figure would be to change the feedstock of the energy sources for all of the vehicles. Cleaning up electricity generation would change the emissions per passenger mile.
Are you referring to ridership estimates, like before a rail line is built? If that is the case, that is a major problem that I see in transit planning. The project selection, prioritization and funding process has become very politicized. In particular places like LA, Denver, St. Louis, where voters are being asked for an increase sales tax to support transit, there is a greater need for accurate ridership and cost projections. But since this lives in the political realm, it appears personally that very typically ridership projections are high and cost estimates are low. It seems to be a frustrating occurrence. The question is this a deliberate action to garner support or honest bad planning?
Yes, I am talking about ridership forecasts before we invest. Otherwise, we don’t really know what we are accomplishing with the investment…
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