Tag Archives: nolan

NYU Rudin CitiBike Presentation at TRB

ActiveStartStations_LGK_0108 [Converted]

NYU Rudin Center Director Mitchell L. Moss and Research Assistants Lily Gordon-Koven and Nolan Levenson presented new findings on CitiBike at the annual meeting of the Transportation Research Board in January.

Findings will be compiled into a post on this site, including interactive maps. A preview is at left, showing most active journey start stations – mostly around the city’s transit hubs. Check back for a full writeup this week.

NYC vs. DC: Pedestrian Showdown

Do pedestrians have more time to cross the street in DC than in NYC? It depends. Both cities have rapidly implemented “countdown” pedestrian signals to give pedestrians a better estimate of how much time they have to cross. This is particularly useful for those who may walk a bit slower than the “average” pedestrian, such as the elderly and disabled.

Countdown Pedestrian Signals in DC display the full cycle length

Countdown Pedestrian Signals in DC display the full cycle length. Source: Eric Fischer, Creative Commons / Flickr

At first glance, it may seem like pedestrians have longer to cross in DC, but here’s the secret: in the District, pedestrians are given the countdown of the full cycle length, whereas NYC pedestrians are only given the countdown for time just before the “don’t walk” phase (the blinking red light or the “clearance phase”).

Countdown Pedestrian Signals in NYC follow the MUTCD and only display "clearance times."

Countdown Pedestrian Signals in NYC follow the MUTCD and only display “clearance times.” Source: Eric Fischer, Creative Commons/Flickr

Why does this difference exist? According to the signal bible, the Manual on Uniform Control Devices (MUTCD) published by the Federal Highway Administration, pedestrian signals should look like the ones in NYC. But wouldn’t you want to know how much time you have total? Not just the “clearance time”?

Are government officials in DC a bunch of rule breakers? Actually, DC was a trial city for implementation of full countdown clocks, but the results of this “test” have yet to be released.

In general, the length of signals for pedestrians depends on volumes of people and traffic on the street. DC usually uses 100-second signal cycles (for all intersection movements) during peak hours, and 80-second signal cycles on nights and weekends. NYC varies much more, with cycle lengths between 45 and 120 seconds.

Sources: Sam Zimbabwe and George Branyan, DDOT; NYCDOT website