Monday, November 5, 2012

Schedule Span

Catching up on Wikipedia transit updates, I happened across this chart of annual ridership, and ridership on a per-mile basis.  While I was pleased as punch about TRAX's success (#9 in the nation), I was less psyched about the ridership per mile. Reading up on other systems, something about the Seattle's 'Central Link' struck me--"Service operates seven days a week, from 5 am to 1 am Monday through Saturday and from 6 am to midnight on Sundays".

I spent most of last night reading chapter 3 of the 'Transit Capacity and Quality of Service Manual, 2nd Edition'. One of the ideas it brought to my attention was the idea of 'schedule span', which is the transit equivalent of hours of operation. The Central Link is operating 20 hours a day. TRAX calls it quit at about 10:30-11, and it starts later! I think that's reflected in the per-mile ridership numbers--almost 2000 vs. just over 1500 daily riders/mile. Central Link is 33% higher than TRAX, for ~33% higher hours.

I've previously commented on the lack of late-night service for TRAX, which (as one commenter noted) has actually been declining over time. Anyone who has read the history of transit is familiar with the ridership sabotaging effects of reducing service. Less service means fewer riders, which means less money, which means less service---it's a downward spiral.

Miles of track are expensive, running between $60m and $100m per mile. We should make as much use of it as possible.