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Letter to Cara Seiderman,
October 17, 1995

John S. Allen
7 University Park
Waltham, MA 02154-1523
(617) 891-9307
Technical writing, translation
Mechanical design, acoustics
Consultant on bicycling
Effective Cycling instructor

October 17, 1995

Cara Seiderman, Pedestrian and Bicycle Coordinator
Cambridge Environmental Program
57 Inman Street
Cambridge, MA 02139

Dear Cara:

This is a significantly expanded and, in a few places, corrected version of the letter I faxed you on Friday.

As I explained in the accompanying letter asking for reappointment to the Bicycle Committee, I have serious concerns about the bike lanes which the City has installed. Let me spell them out for you in order to help you prepare a response for next month's meeting. I want to give you the opportunity to think about them at length, instead of unloading them on you all at once at the meeting.

As I begin this, let me first say that I very much want the Cambridge Bicycle Program to succeed. I have given a large part of my adult life to advocacy for bicycling, and hundreds of hours to the Bicycle Committee's efforts, beginning with my participation in the first meeting at Walter Willett's home, 5 years ago, about approaching Mayor Wolf to suggest a Bicycle Committee.

I also want you to succeed in your office. I want to be able to support you and will help you any way I can, within the limits of good conscience. I have been eagerly awaiting, for example, the opportunity to bring my knowledge of the traffic law to bear on the Bicycle Policy. I put this in boldface because I want you to remember it if anything else in this letter discourages you. I also very much regret that my overwhelming work load earlier this year when working on the State Bicycle Facilities Inventory prevented me from participating more fully in the Committee's work at that time. With 20/20 hindsight, I very much would prefer to have stated my concerns about the bike lanes earlier. On the other hand, I felt that it was appropriate to give the City the benefit of the doubt with its first major bicycle facilities, and I am not sure that details of most of the bike lane designs were ever brought before the Committee for review. The criticisms at the October meeting from Rebecca and Walter suggest that they were not. I do recall your meeting with me to discuss Brattle Street, though we never discussed the other locations.

I recognize that you have performed a lot of good work in bringing the bicycle program together and advancing its position among the City's priorities. However, I am very concerned about the specific designs and design approach of the facilities which the City is building. My impression, in general, is that you personally are setting the tone for the City's efforts, attempting as nearly as possible to apply the northern European model for bicycle facilities, with which you are familiar.

I have never known this approach to succeed in an American city, though it has been tried many times. There are many reasons that it does not succeed, but the primary one is that neither cyclists nor motorists in this country accept the major increases in travel time that are inevitable if a pedestrian-style intersection treatment for cyclists is to be reasonably safe. The inflexible designation of different parts of the street for different types of vehicles also contributes to these safety problems and inefficiencies. It has proven unrealistic, as well, to expect American cyclists and motorists to adopt complicated exceptions to the standard traffic law. It is difficult enough to obtain compliance with standard American traffic law. I do not mean this as a swipe at Americans, though I personally am careful to obey the law when cycling and driving. Rather, it is a reality which we must acknowledge and which holds important lessons for us.

Let me give an example. An anti double-parking campaign is accompanying the bike lane introduction. It is convenient to point the finger of blame at motorists who park in a bike lane, but many of them are truckers who have no alternative in a city where very few small businesses have back alleys or loading docks. Bike lanes are likely to be unpopular with truckers and merchants because of this difficulty. The conversion of a substantial percentage of metered curbside parking spaces into loading zones might relieve cyclists of the need to merge to the next lane to pass double-parked vehicles, but is likely to meet strong opposition from merchants. On streets with no curbside parking to convert into loading zones, I can envision no convenient way to prevent illegal parking by truckers. In any case, double-parking often works to the advantage of cyclists, since it is a far greater inconvenience to motorists. All in all? Double-parking is a much more complicated issue than it may seem at first.

I am distressed that no discussion of fundamental design approaches has occurred yet in the Bicycle Committee, while the City goes ahead with facilities design and construction. I hope that next month's meeting provides an opportunity for such a discussion. I am also concerned about the City's failure to make effective use of valuable, available design and planning resources. When, months ago, you reported that you were surveying the efforts of other American cities and states for input about facilities design, I thought that the City was on the right track; but something appears to have gone wrong with this effort.

I note with special dismay and considerable astonishment that Cambridge did not consult Josh Lehman, our own Massachusetts Bicycle-Pedestrian Coordinator, about its proposed projects. Josh took the job of Seattle Bicycle Coordinator over 15 years ago and has worked professionally in the field ever since at the highest levels. He is a gold mine of information about design and about how to shape a bicycle program to achieve political success. We are extremely fortunate to have him in Massachusetts. Sure, Cambridge is not obliged to consult Josh about bicycle projects unless they are on state highways -- but other Massachusetts cities and towns do. You have other professional colleagues such as Cathy Lewis and Alan McClennen who could also be of great assistance with Cambridge's efforts.

My specific concerns about the bike lanes:

1) Most of the width of the lane on Mt. Auburn Street which is next to parking is within the range of opening car doors. A lesser width of the other lanes next to parking also is too close to car doors. At speeds above 5-8 mph, there's no way to avoid an opening car door. Many cyclists will assume that the bike lane somehow protects them and prevents motorists from opening their doors. When cyclist is "doored" in a designated bicycle lane, there is no recourse against the motorist who opened the door, because Massachusetts has no law prohibiting motorists from doing this. Therefore, the City becomes the primary target for a liability suit.

Cyclists who do know enough to move out of the lane for the sake of their safety will be harassed by motorists. The bike lanes can also lead cyclists to ride too close to the overtaking traffic: for example, when there are no parked cars in the parking lane. There is no single position on the road which is correct for cyclists in a changing traffic situation. It doesn't matter that the law permits cyclists to ride outside the bike lane, since many cyclists and motorists will assume that the painted lines tell cyclists where they MUST ride.

2) Intersection treatments: some use no dashes, though I understand this was a mistake. Dashes that are used are very short, nonstandard ones which blend into a solid line from the distance at which they must be seen. I see a serious liability risk in this. The dashed sections are too short to serve their purpose of indicating that motorists should merge into the bike lane before a turn, which leads to my next point.

3) You have expressed your belief to me that motorists should not queue up in a bike lane to make a right turn, but rather should queue up to the left of the bike lane. The only question in my mind is "What's the best way to change your mind about this?"

If you are persuaded by names and credentials, I can get a steady stream of traffic engineers and accident reconstruction experts to contact you with information that this is inherently a dangerous practice.

If you are persuaded by analysis and studies, I can get them too. If you are persuaded by the threat of multi-million dollar liability judgments, I can put you in touch with attorneys and accident reconstruction experts who will tell you the assigning of fault in intersections like this.

If you are persuaded by bad publicity, I can show you many examples of the kind of unfavorable article which is published following the construction of ill-designed lanes. The success of any bicycle program depends heavily on the public's reaction to the first facilities installed. This reaction to Cambridge's first facilities will extend through the entire Boston area. Though I haven't seen it yet, I understand that a less than glowing article has already appeared in the Globe City Weekly (I get the West Weekly).

While Chapter 90E, section 1 of the General Statutes defines a "bike lane" as "a lane on a street restricted to bicycles and so designated...," Chapter 90, section 14 states that "When turning to the right, an operator shall do so in the lane of traffic nearest to the right-hand side of the roadway and as close as practicable to the right-hand curb or edge of the roadway." No exception is stated relative to lane restrictions. My understanding is that specific prescriptions of the law override general ones, and I know of no situation in which a driver is permitted to cross a through lane when turning right. May I suggest that you obtain an opinion on this issue from the City Attorney if you have not done this already, and bring it to the next Bicycle Committee meeting?

Many vehicles, especially large trucks and buses which are most dangerous to cyclists at their side when turning, offer the driver very limited vision to the right, so it is very difficult and sometimes impossible for the driver to see a cyclist on the right.

Most importantly, a fundamental principle of traffic engineering is for drivers to merge to the correct lane position before intersections, in order to be able to pay full attention to the traffic ahead. A motorist looking over her shoulder for a cyclist is much more likely, for example, not to notice a pedestrian who has stepped off the curb ahead, or a changing traffic light.

The classic Cross-Fisher study of car-bike collisions indicates that a right turning car striking a cyclist on its right is already the #3 car-bicycle collision type for adult cyclists in urban areas. The #1 type is an oncoming motorist turning left into a cyclist -- also made more likely when a cyclist overtakes a vehicle on the right where oncoming motorists can't see her and she can't see them. The results of the Cross-Fisher study have been very closely corroborated by a study which the MAPC conducted in the Boston area.

These studies are old enough that the remedies to these kinds of accidents have become common wisdom among thousands of traffic engineers and safety experts, and I am very disturbed by the City's needing to rediscover that facilities of the kind can be made safe only with an all-out pedestrian-style treatment with separate signal phases for cyclists and motorists, and a compliant population which is willing to accept serious inconvenience and delay.

Again, a commonly-held outgrowth of the Cross-Fisher study, other similar studies, and of the work of many talented individuals and governments nationwide is the widespread common wisdom that we should instruct cyclists to use normal traffic principles to deal with intersections. A cyclist's look over the shoulder and slight merge to the left discourage right-turning motorists from overtaking on the left, and in many cases permit a right-turning motorist and through cyclist both to continue through the intersection without conflict or delay. This is simpler, easier and safer than having the cyclist remain too far to the right. It is how thousands of cyclists, including myself, have ridden for decades in Boston area traffic, and it works just fine.

These concepts of how a cyclist should behave in traffic were once new to me, as they were to everyone, and I grant you that they may sound counter-intuitive. But when I tried them, as have hundreds of thousands of cyclists who have been exposed to them, I discovered a new level of confidence and safety in my bicycling. Cyclists who are too inexperienced or timid to merge have the lawful options of crossing as pedestrians in the crosswalk, or waiting until the traffic clears before they approach the intersection.

Finally, let me hope that you and the City may learn to be confident in not installing bike lanes where they pose problems of the type I have described. Credible studies, for example Wachtel and Lewiston in the September 1994 ITE Journal, show no safety improvement even from bike lanes which I may presume benefit from more design experience than can have informed Cambridge's first efforts. My personal preference would have been for the City only to increase available width for cyclists and motorists to share the right lane in most places it has installed bike lanes, perhaps adding the "bike arrows" that Paul Schimek has described to me, a guide stripe as on Broadway, or long dashes outside the parking lane as on Commonwealth Avenue west of the BU Bridge. My understanding is that Paul will be incorporating descriptions of alternative treatments in the document which he and I are preparing for the next Bicycle Committee meeting.

I look forward to a positive and fruitful discussion at that meeting.

Very truly yours,

John S. Allen

enc.     my pamphlet Street Smarts.
reappointment letter to the City Manager
my curriculum vitae

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