Save the Bike Lanes on Concord Ave!

Concord Avenue "Bicycle Lanes"
Concord Avenue 'Raised Bicycle Lanes' - Not Part of "Roadway"

Concord Avenue north of Fresh Pond in Cambridge has perfectly nice, five-foot bike lanes. They’re not even in the door zone, since there is no on-street parking. But Cambridge is planning to take them away, narrow the roadway, and force bicyclists to ride on the sidewalk. The bike lanes were striped 10 years ago as part of a successful “road diet” project. John Allen has posted a history and more information about the proposed project. The current project, whose limits are Fresh Pond Parkway and Blanchard Road, includes water main installation and started this week.  The planned “raised bike lanes” are at sidewalk level and in most places will be separated from the travel lanes by a 6-inch high curb. A bicyclist who strays too close to the edge of the “bike lane” risks falling into the travel lane. In other words, the new “bicycle lanes” are really “sidewalks”. A sidewalk by any other name is still a dangerous place to ride a bike at anything faster than walking speed. Look at the above excerpt from the construction drawings. They show clearly that the “roadway” includes the “travel lane” but not the “bicycle lane.”  This turns out to be an important detail.

MassDOT’s Engineering Directive on Bicycle Accommodation says that “Bicycle accommodation shall be in accordance with Chapter 5 of the [Project Development & Design] Guide and the 1999 AASHTO Guide for the Development of Bicycle Facilities.” What do those documents say? Chapter 5 of the Project Development & Design Guide says: “Bicycle lanes are portions of the traveled way designed for bicycle use. .  .  . Bicycle lanes should be designated by a 6-inch solid white line on the right edge of the motor vehicle travel lane [sic].” (section

The 1999 AASHTO Guide for the Development of Bicycle Facilities is more precise. It has the following definitions: “BICYCLE LANE or BIKE LANE—A portion of a roadway which has been designated by striping, signing and pavement markings for the preferential or exclusive use of bicyclists. ROADWAY—The portion of the highway, including shoulders, intended for vehicular use.” It further says that “A bike lane should be delineated from the motor vehicle travel lanes with a 150-mm (6-inch) solid white line.”

In other words, the official design manuals say that bike lanes are part of the roadway, not the sidewalk, and are separated from other lanes by lines, not curbs. The AASHTO bike guide also includes this helpful guidance: “Sidewalks generally are not acceptable for bicycling. However, in a few limited situations, such as on long and narrow bridges and where bicyclists are incidental or infrequent users, the sidewalk can serve as an alternate facility, provided any significant difference in height from the roadway is protected by a suitable barrier between the sidewalk and roadway.” The Concord Ave project clearly does not meet the requirements for exceptional designation of a sidewalk as a bike facility, and even if it did, the design guidelines require a barrier to prevent bicyclists from falling into the roadway — an important detail that Cambridge has not followed in this project.

Well, what if Cambridge just edits the drawings so that they say “bicycle path” instead of “bicycle lane”? One problem is that there is no design standard for a bicycle facility on the sidewalk that prohibits pedestrians; the only standards are for “shared use paths” — shared by pedestrians and bicyclists. Moreover, the Project Development & Design Guide says this: “Shared use paths are facilities on exclusive right-of-way with minimal cross flow by motor vehicles. Shared use paths should be thought of as a complementary system of off-road transportation routes for bicyclists and others that serves as a necessary extension to the roadway network. The presence of a shared use path near a roadway does not eliminate the need to accommodate bicyclists within a roadway” (Section If Cambridge were to call the “raised bicycle lane” a “path” it would not be able to narrow the travel lanes to only 12 feet, as proposed, but would have to leave at least another 3 foot shoulder to provide the minimum 15 feet of room for motorists to comfortably pass bicyclists according to MassDOT’s Engineering Directive previously mentioned.

Ok, but does Cambridge really have to follow these design guidelines? To pay for this project Cambridge applied for and apparently received a grant from the Public Works Economic Development (PWED) Program, formerly administered by the Executive Office of Transportation, now part of MassDOT. So it would seem that MassDOT’s own Engineering Directive should apply.

If not, there is a higher authority. All traffic control devices in the U.S. must conform with the Manual on Uniform Traffic Control Devices published by the Federal Highway Administration. The manual has the following definitions:
Bicycle Lane—a portion of a roadway that has been designated for preferential or exclusive use by bicyclists by pavement markings and, if used, signs.
Roadway—that portion of a highway improved, designed, or ordinarily used for vehicular travel and parking lanes, but exclusive of the sidewalk, berm, or shoulder even though such sidewalk, berm, or shoulder is used by persons riding bicycles or other human-powered vehicles.”
In other words, a Bicycle Lane that is not part of a roadway does not comply with the manual.
Noncompliance with engineering directives and design manuals could mean that Cambridge would be held liable by a court in the event of a lawsuit by an injured bicyclist.

The Livable Streets Alliance endorsed the project, saying, “The Concord Avenue reconstruction plan pushes for best practice for street design. It includes well-designed and inviting facilities for pedestrians, bicyclists, and motorists alike. Of particular note, there is a raised bicycle lane (cycle track) included as part of the project, a type of facility that has been gaining interest among the public, but which we currently have very few of.” WalkBoston endorsed it as well.

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