Cambridge Civic Journal Forum

May 16, 2011

About bicycling issues on City Council agenda tonight, May 16, 2011

A cyclist and a motorist approach the blind corner at Concord Avenue and Follen Street

A motorist cuts off a cyclist at the blind corner of Concord Avenue and Follen Street

The city's own picture of this scene shows a cyclist happily steering straight toward a curb.

A picture of the same scene from the City's Web site shows a cyclist happily steering straight toward a curb, which is cropped out of the picture.

Looking from the opposite direction, this is the path a bicyclist must take, swerving toward traffic to reach the curb cut.

Looking from the opposite direction, this multiple-exposure photo shows the path a bicyclist must take, swerving toward Follen Street traffic to reach the curb cut at the crosswalk.

This post attempts to shed some light on agenda items on tonight’s City Council agenda.

The quoted sections are from another commenter. I’m not sure I know how to reach him, and time is pressing. I don’t know whether I have permission to use his name, so I won’t. The unindented paragraphs  are my own. We’ll start with the other person who commented.

Two of the three items on the city council agenda are interesting examples of problems related to bicycle infrastructure that has been implemented over the past several years.  The third is simply a request to fill potholes, but includes an ignorant comment about bicycles needing to ride near the curb (not true according to Massachusetts law or Cambridge ordinance).

That is agenda item O-7 on the page linked here

The first bicycle facility problem is a contra-flow lane through a blind corner where motorists have no expectation that there will be contra-flow traffic of any sort as they round the corner on a one-way street.

That is agenda item O-3 on the page linked here.

The street view is looking south on Follen Street as it intersects (Little) Concord Avenue.  The bike lane crosses in a contraflow manner from left to right, and then continues across the small brick plaza to the right to join with Garden Street and the continuation of Concord Avenue.  The intersection just beyond the plaza is the same one where Cambridge has installed a bike box critiqued by John Allen


The contraflow bike lane is adjacent to wrong-way parking, another odd feature of this installation — see this for a description and explanation of wrong-way parking:

Upon reaching the corner, bicyclists have to ride out past a stop bar and stop sign before they can see around the corner. A stop sign requires two actions, a stop and a yield. The yield is what actually prevents a collision — but it is only possible where you can see conflicting traffic.

Many if not most of the bicyclists approaching this intersection are Harvard students headed up to the Radcliffe quadrangle. Are we to assume that they aren’t bright enough to figure out that they must yield? The problem is that nobody ever instructed them, and many have little bicycling experience as they suddenly find themselves dependent on a bicycle for transportation. Also, the stop bar isn’t where there’s anything to yield to unless a pedestrian happens to be crossing — it encourages running the stop sign, sort of like traffic ju-jitsu: aha– fooled ya!.

See Google Street View looking toward the stop sign:

I have a discussion of this contraflow bike lane in the page linked below this paragraph. The third photo down the page shows the stop sign. I prepared the page linked below years ago, shortly after the installation. This was clearly going to be a problem location.

The curb ramp on the far side of the intersection is located at the end of the crosswalk rather than in line with the bike lane. Bicyclists must ride toward approaching traffic to reach the ramp.

Bicyclists coming in the opposite direction off the little pedestrian plaza are hidden by a wall and subject to similar risks. This entire treatment is a prime example of Cambridge’s principle of Design by Wishful Thinking.

The second problem is at a rather unremarkable intersection, so it is not clear to me why there would be issues.

See Council Order O-19 on the page linked here.

The street view is looking south on Ellery Street as it approaches Broadway.  Ellery is a narrow one-way street with a bike lane.  Traffic is typically slow, but can be heavy at rush hour.  Broadway is a two-way narrow connecting through street with parking and no bicycle infrastructure in this area.  Traffic typically runs about 25-30mph, slower and heavier at rush hour.  The intersection is also at the corner of a local public high school campus.  Neither street is difficult to cycle on if you have at least modest traffic experience.

There is a flashing yellow and red overhead signal indicating a stop sign for Ellery Street entering from the north.  I tried to find data related to the several accidents cited, but did not see anything apparent on the Cambridge city web site.  I can speculate that most of the car/bike accidents are probably due to scofflaw behavior — either bicyclists in the Ellery bike lane not heeding the stop sign as they continue across Broadway, or wrong-way riders in the Ellery Street bike lane illegally approaching Broadway from the south.  Also likely would be standard right hook, left cross, and failure to yield collisions caused by motorists, but I don’t see why those would be any worse at this intersection.

I see a double-whammy right-hook provocation for bicyclists headed south on Ellery Street, in that the bike lane on the far side of the intersection is to the left of parking (and in the door zone, as is usual in Cambridge), while the bike lane on the near side is at the curb and carried all the way up to the intersection. So, bicyclists are encouraged to overtake motorists on the right, then merge left inside the intersection where motorists turn right.  I think that the high traffic volume and prevalence of high-school students probably also account for the number of crashes. There probably are scofflaw crashes too. Yes, it would be very interesting to see details so as to get a handle on what is actually happening here.

I’m not looking for any answers, but I thought people on this list might be interested in what Cambridge lawmakers are thinking.


  1. I was just in NYC. On 8th avenue starting in Chelsea – one way uptown. There is a bike lane, clearly marked, then a no-car zone, then a “metered” parking lane and then the traffic. They can have parking out there since they use ticket machines instead of coin devices at each spot. There are separate traffic signals for the bikes with little bike figures in the light. Before streets where there is a left turn allowed, they end the parking lane and have space for a few left-turning cars in that space. Using ticket machines instead of per-spot meters makes it feasible to put the parking out there.

    Comment by gintell — May 16, 2011 @ 5:32 pm

  2. I’ve ridden the facility on 9th Avenue, the one-way southbound street paired with 8th Avenue, and with the same treatment — much better engineered but still with significant flaws. A detailed description, video and commentaries on it can be found at

    Comment by jsallen — May 17, 2011 @ 9:12 am

  3. The City Manager has a response (from Brian Murphy at CDD and Sue Clippinger at T&P) to the Follen Street situation in a letter for the May 23 City Council meeting:

    May 23, 2011
    To the Honorable, the City Council:

    In response to Awaiting Report Item Number 11-53, regarding a report on way to make the Follen Street/Little Concord Avenue intersection safer for pedestrians, bicyclists and motorists, Assistant City Manager for Community Development Brian Murphy and Traffic, Parking & Transportation Director Susan Clippinger report the following:

    The design of this bicycle facility (contraflow bike lane) was done with the reconstruction of Arsenal Square, Follen Street and “Little” Concord Avenue in the mid 1990s. At that time, an analysis was done for bicycle, pedestrian, and motor vehicle travel and it was found that a large number of cyclists use this travel corridor, with essentially an equal number of cyclists traveling in each direction. Motor vehicle volumes on the street are very low and most drivers are ones who live there and use the street regularly. The contraflow lane was installed to improve safety for cyclists by creating a dedicated facility for them to ride in and through the presence of pavement markings to remind motorists that bicyclists are traveling there.

    In response to the Council Order, staff have looked again at the site and determined that we will improve the signing and add pavement markings to remind all users to exercise care and caution at the intersection. In addition, a “Watch for Crossing bicycles” sign has been ordered for Follen Street that we expect will arrive and be installed in 4 weeks. We also will be marking the alignment of the bicycle lane by dashed lines where the bicycle lane crosses Follen Street. The pavement markings will be installed in July although the mark out may occur sooner. Cambridge Police will also be present to reinforce the importance of cyclists stopping at the stop sign.

    Very truly yours,
    Robert W. Healy
    City Manager

    Comment by Robert Winters — May 20, 2011 @ 12:28 am

  4. My comment formerly posted here was long, and so I have made it into a separate post.

    Comment by jsallen — May 20, 2011 @ 10:40 am

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