Thursday, April 22, 2010

Inman Street, Cambridge by Stefanie Beaver

Inman Street in Cambridge is a one way street with one travel lane, one bike lane and one parking lane. The bike lane is separated from the travel lane by a single white lane line, and somewhat separated from the parking lane by small markings for individual parking spaces. The intent of this treatment was to distinctly separate the motor vehicle lane from the cyclist lane so they wouldn’t have to fight for space on the road. This treatment achieves that goal somewhat, in that the lane line does make drivers better able to predict where the cyclists will be, and makes both cyclists and motor vehicle drivers feel safer and more comfortable. The issue with this treatment is that there is no lane line separating the bike lane from the parking lane. If there was a line separating these two lanes it would encourage the cars to park closer to the curb and it would encourage the cyclists to travel farther away from the parked cars. The current placement of the bike lane is not ideal because it places cyclists in the door zone, which is the area two to three feet beyond a parking lane where cyclists are in danger of being struck by a car door opening. Although the placement of the lane is not ideal, it is still better to have a lane than not to. An example of this is shown in a study done in Cambridge on Hampshire Street of a similar situation. That compared a street with no lane markings, a lane separating the bike lane from the travel lane but not from the parking lane, and lane lines separating the bike lane from the travel lane and from the parking lane. The results of the study showed that with the two lane lines, cyclists travelled further from the parked cars, and the motor vehicles and cyclists actually travelled closer together because they felt safer and more comfortable. An improvement I would recommend for Inman Street would be to add another lane line separating the parking lane from the bike lane.

1 comment:

  1. This is NOT a bike lane; that's the whole point, and unfortunately, this analysis missed it. The street width and dimensions of the different parts of the street are critical parts of the treatment (and of the options for treatment), and unfortunately are not reported.