Monday, August 4, 2014

Bike Lanes (and sharrows) require buffering from the door zone

Photo courtesy of NACTO.org
By Steven Vance, Streetsblog -- A new study has found that buffered bike lanes are better than conventional bike lanes when it comes to encouraging bicyclists to ride outside the door zone. The study draws its conclusion, in part, based on a test done with bike lanes in Chicago.

The study, recently published by the Transportation Research Board, concludes that wider but un-buffered bike lanes aren’t necessarily better than narrower lanes in encouraging bicyclists to ride outside the door zone. If there’s enough space to make a wider bike lane, the authors conclude, that extra space should be used to install a “narrower bicycle lane with a parking-side buffer,” which “provides distinct advantages over a wider bike lane with no buffer.”

Researchers reached their conclusions after observing thousands of cyclists using various bike lane configurations in Chicago and Cambridge, Massachusetts. On one Chicago street, for example, few bicyclists rode outside the door zone when the bike lane had no buffer, then after a two-foot buffer was striped, 40 percent rode outside the door zone. [Full article ...]

Poster's note: On the recent Tour of Vermont and New Hampshire, the City of Pittsfield, Massachusetts had sharrows placed directly in the door zone along primary streets. As stated in Wikipedia, the purpose of the sharrow is to "Assist bicyclists with lateral positioning in a shared lane with on-street parallel parking in order to reduce the chance of a bicyclist’s impacting the open door of a parked vehicle", so it is not clear what traffic engineers were thinking when these were installed (photos below).

2 bicyclists caught in the act, riding against traffic. Is it contempt, or the persistence of Bike Salmon?

Any cyclist riding within the sharrow footprint here is eventually going to get whacked with a car door.


The above video perfectly illustrates the issue, and provides educational tips for motorists. We don't believe DelDOT would ever be silly enough to try this, but as advocates, we must be on our guard at all times. This includes when bike lanes are proposed for streets that include parallel parking.

Both Wilmington and Newark followed the guidelines when it comes to sharrow placement. Market Street (above) and Main Street have their sharrows at or near the center of the lanes, well outside the door zone where they belong.

No comments:

Post a Comment

Note: Only a member of this blog may post a comment.