A caution for bike sharing in NYC

The Bixi bike share system chosen by NYCDOT is a proven platform that addresses a lot of concerns that New Yorkers might have about bike sharing. Thefts have been low in recent Bixi installations; 0.0002% of bikes checked out in London over the first year never returned. The footprint of the system is pretty well centralized, which will ensure that plenty of daily users are around to foot the bill.

My principal concern with launching bicycle sharing in NYC is that it will be very difficult to keep the bikes/spaces balanced, the biggest operational problem that’s emerged in urban bicycle sharing. Alta has acknowledged its challenge in DC and it’s been a leading complaint in London (watch the striking daily inflow/outflow here); so far, these are the two biggest CBDs that have bike sharing. The operational environment for rebalancing in all other bike-share cities is far simpler than in Manhattan.

Bike share works best in areas of medium-high density and very high mixed-use, since it requires that a large number of people circulate bikes around the system, around the clock. That way, the bikes naturally circulate themselves without much intervention. Many European and Asian cities are organized in a way that’s fairly conducive to bike sharing. Their density curves are not that steep, and many neighborhoods have 18- or 24-hour street life. Moving a lot of people to a single point — i.e., very high density, single-use concentrations, is a job most efficiently done with transit whether that’s shuttle buses for sports stadiums or rail feeding a CBD. The capacity numbers speak or themselves: at any given moment, ~1200 people can use Capital Bikeshare, while Washington Metrorail runs enough trains at peak to move 153,000 people at once.

Even in London, the City is overwhelmingly mid-rise, and high-rise, office-heavy Canary Wharf is outside the bike share footprint. North American bike sharing programs so far are either in comparatively small cities (Minneapolis, Denver, a fraction of Toronto) or in cities with an exceptionally “European-style” mid-rise and/or mixed-use core (Washington, Montreal, that fraction of Toronto).

A bike share system attempting to serve Manhattan’s highly centralized employment density will be quite difficult to manage. DC and London both struggle with office cores twice the size of Montreal’s; NYC has a CBD that is seven times as large. A vast number of docks will be demanded within the office cores, where street space is already at a steep premium. Rebalancing vehicles will not be able to easily cycle bikes amidst streets already clogged with delivery vehicles. Without an ability to rebalance bikes, it will be difficult to find bikes in Brooklyn, or open docks in Midtown, during the day. Paying customers who are thus kept out of the system will get very upset.

What might work? Unfortunately, we can’t know which sites will have a fairly balanced flow of coming and going throughout the day, but that could be inferred based on observation of adjacent land uses. A high-density or vertical racking solution like the (as yet theoretical — I’ve only seen a mock-up) Bike Dispenser might come in handy for swallowing, or ejecting, vast quantities of identical bike-share bikes at key locations like rail terminals.

A class that I’m in this semester will investigate bike share rebalancing worldwide; keep an eye on the class blog for updates and the final report.

I recently got to ride with Tom Bertulis on Boston’s “Hubway”; he pointed to Seattle’s helmet law (among the few for adult cyclists in North America) as a serious impediment to introducing bike sharing there. I have to admit that although I wear a helmet 99% of the time with my own bike — since I keep helmets near my bikes and typically plan such trips — I often neglect to when riding bike share. Tom Fucoloro from Seattle Bike Blog notes bike share’s exemplary safety record, and (as Tom B. also did) Mexico City’s repeal of its helmet law in favor of bike sharing, to argue for at least modifying Seattle’s law.

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7 thoughts on “A caution for bike sharing in NYC

  1. Most places in Brooklyn are more than half an hour from the “office cores” by slow clunky bike-share bike, so I don’t think there will be a mass exodus of bikes from Brooklyn stations to Manhattan every day. Also most “office cores” are located on transit, so for folks who want to bike at least part of the way to work, it would be more convenient to pick up the local share bike and ride to an express station in Brooklyn.

    And midtown is compact enough that it would be cost-effective to hire people to rebalance bikes two-by-one from the “office cores” to the railroad stations. Ride one bike and ghost the other.

  2. Many bike share commuters in other cities have switched from transit. It doesn’t matter that offices are usually convenient to transit — so are most offices in central London, DC, and Montreal. Besides Times Square, there are few locations that are convenient to everyone’s transit lines. Thus, a lot of people might forego dealing with transit transfers (particularly cross-town transfers) and instead take one train and bike the last mile (last few blocks) to their workplaces.

    Overall, bike share systems will eventually have to disabuse their users of the notion that the system’s intended for single-mode commute trips; such flows are inherently temporally unbalanced.

    I’ve tried ghosting these bikes, and it isn’t exactly easy! The economics also don’t seem to work for ghosting: if each ride brings in $0.70 in revenue (typical trip is <30 minutes) and a person costs $20/hour including overhead, that person would have to rebalance a pair of bikes every four minutes to justify their cost. Even in a best case scenario with one full station and one empty station a two-minute ride (three-minute walk) away, and one minute for docking and re-docking, you can only move a pair of bikes every six minutes.

  3. In a city like New York, I would expect that bikeshare would be most useful for taking trips where public transit is slow or sparse (e.g. crosstown in Manhattan), or riding the last mile to or from the subway stop in residential neighborhoods. When the bikes are used for the first purpose, I would not expect the kiosks to get unbalanced in most cases (I don’t think we would expect more people to ride from the West Side to the East Side than vice versa).

    If riders go to and from a subway station, I would expect to see the bikes pile up at the subway stop in the morning; then, in the afternoon, the flow would reverse. For this use, you would WANT the bikes to be unbalanced from one hour to the next, to accommodate predictable surges in demand.

    Occasionally, it might be necessary to do a bit of rebalancing, but I don’t understand why it should be something that has to be done every day. Am I missing something?

    When rebalancing is necessary, it should be possible to do it the way Jonathan suggests, riding one bike and ghosting another. I’ve seen that done by B-Cycle in Madison.

  4. Sounds like you’ve thought extensively about this. I think that a lot of it has to do with the marketing as to who will take advantage of it and who will not. Even though bike share seems like it might help out commuters,if the program is marketed to students, tourists, and recreational uses, it might not have those same problems.

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