Category Archives: Sidepaths

Davis Planners and Advocates Opine on Sidepaths

This post supplements my previous post linking to documents about Davis bicycle facilities. Please bear in mind that Davis was the first community to introduce bike lanes in the USA, and that its bicycle program strongly favors conventional bike lanes, which are separated from the adjacent lane only by a painted stripe. However, I have found that the Davis documents uniformly and strongly recommend against bike lanes behind barriers or parked cars. Not only that, the recent warnings are more definite than the early ones. Some quotes, starting with the most recent and working backwards in time:

Theodore Buehler, Fifty years of bicycle policy in Davis, CA (Master’s thesis, 2007). See pages 50 ff., “Lane location relative to motorized traffic”.

The early experiments included three different types of bike facilities (see examples at the top of this section):

  1. bike lanes between car lanes and the parking lane (Third St.),
  2. bike lanes between the parking lane and the curb (Sycamore Lane), and
  3. bike paths adjacent to the street, between the curb and the sidewalk (Villanova Ave.).

The first bike lanes included all of these types, to test them in real life to see how effective they were. The on-road lanes worked best, the behind-parking lanes were the worst, and the adjacent paths were found to work in certain circumstances. This is an example of the wide level of experimentation that occurred during this period. Had the city tried to do extensive research without construction, it might have settled on an inferior design. And not having tried all three designs, it might not have recognized it as inferior, and the entire experiment could have been declared a failure.

Dale Lott (one of the early advocates for special bicycle facilities in Davis, who also conducted research as to their safety and effectiveness), “How Our Bike Lanes Were Born“, op-ed piece which appeared in the Davis Enterprise in 2003:

We insisted on some experiments that turned out well and some that were flops.

One flop was on the first block of Sycamore north of Fifth where we put bike lanes next to the curb with parking next to the auto travel lane. It looked great on paper, but was a mess on pavement. When cars turned into the University Mall driveway, they crossed the bike lane. Both driver and rider, whose view of each other had been obscured by the parked cars, had an emergency situation.

David Takemoto-Weerts (University of California, Davis Bicycle Coordinator, A Bicycle-Friendly Community, the Davis Model (conference presentation, 1998)

Because Davis pioneered the bike lane and other bicycle facilities in this country, it is not surprising that some “experiments” were less successful than others. One such example was the construction of “protected” bike lanes where motor vehicle and bicycle traffic was separated by a raised “buffer” or curbing. In some cases, the bike lane was established between the parking shoulder and the curb line (i.e. cars were parked on the left of the bike traffic lane). Needless to say, any “benefits” of such facilities were soon found to be outweighed by the many hazards created for their users.

Most such well-intentioned, but ill-fated designs were phased out long ago. However, some facility design decisions made decades ago were not so easy to remedy. The most pervasive example in Davis is the two-way bike path immediately adjacent to a roadway. Particularly problematic are single two-way paths located on only one side of the adjacent road. The problems associated with these designs have been described in any number of publications, and they are well illustrated at several locations in Davis. In spite of this documentation, some residents, city officials, and developers remain quite vocal in advocating such facilities when new construction is being planned and designed. The city and campus have attempted a variety of mitigation strategies to reduce the hazards or inefficiencies associated with these side paths, but many observers believe that continuing to build such facilities is wasteful at best.

Deleuw, Cather and Company.: Davis Bicycle Circulation and Safety Study. 1972 (excerpt — for complete document in three parts, see table of contents page.

Protected lanes

…Protected lanes located between the parking shoulder and curb line have most positive separation. However, the parked cars create sight distance problems at driveways and intersections. Inability to cross streets in midblock in this type of treatment results in two-way usege which, in turn, leads to intersection problems described subsequently…

Sidewalk and Independent paths

Sidewalk pathways eliminate midblock bike-motor vehicle friction. However, frictional interference of pedestrians may discourage usage of these facilities as does frequent interruption by cross streets and driveways or meandering of the path. An additional problem is establishment of a visual relationship between motor vehicles on the sidewalk path on approaches to intersections…

Guest posting by John Schubert: New York, City of Confrontation

Responding to an article in the New York Times, a correspondent asked John Schubert

Why isn’t NYC concerned about being sued because of lousy bike-lane-
design-caused wrecks?

and he replied:

Good question. I think it’s important to know the answer from NYC’s point of view. I’m not their spokesman, but I’ll try.

First of all, they get sued no matter what they do. It’s a city of confrontation.

Second, NYC knows it will always have collisions, injuries and deaths. They would not view any one street design as a perfect protection against these problems, nor against litigation.

Third, they are SO bombarded with aggressive drivers, nonmotorized road users wanting some sort of relief from aggressive drivers, and the usual paint and path propaganda, that they buy into the idea that separation is necessary in NYC, even if not elsewhere, because NYC is unique.

I believe NYC does have a civility problem. Separated bicycle facilities don’t solve that problem, but in the minds of true believers, at least they avoid that problem. I think you can’t have a livable community without addressing THAT problem.

NYC does have other unique concerns. I suspect the biggest is the huge volume of midblock car stops, more than anywhere else, mostly because of taxis getting and discharging passengers. I think the designs they use to answer this are silly, but the ‘vehicular cyclist’ alternative hasn’t been made appealing to them. Yet.

Ciccarelli on cycle tracks

John Ciccarelli is a consultant on bicycling and a League of American Bicyclists-certified cycling instructor who specializes in teaching adults who have never ridden a bicycle before. His comments here are reprinted by permission, and are in response to an e-mail he cites.

Subject: Re: Making Cycling Irresistible: Lessons from the Netherlands, Denmark, and Germany
Continue reading

Livable Streets proposal lacks credibility

I’m looking at a GOOD magazine/Streetsblog proposal for a “livable street”

This is a prime example of what I call the Photoshop school of traffic engineering. Anyone with computer graphics skills can generate a before-and-after comparison like this. Often, it looks very attractive to the untrained eye — but, whether the proposed changes make sense is another issue entirely.

It would be nice if the Streetsblog people who created this graphic had a few more clues about street design. Some of the issues:

Continue reading

Technical and legal issues with the NYC 9th Avenue bikeway

All intersections along the NYC 9th Avenue bikeway are signalized, and it has separate bicycle signal phases at most of them. At the time of the field trip, December 5 and 6, 2008, some of the signals (especially at the north end) had not yet been installed or were not yet working, and so another visit to the site would be useful to view the complete installation.

Manhattan has typically in the past (since Henry Barnes set it up in the 1960s) had signals on the one-way avenues timed in sequence for 30 mph, except at two-way cross streets where that was not possible.

Continue reading

Guest posting: John Ciccarelli on the NYC Broadway bikeway

[John Ciccarelli is a consultant on bicycling, League of American Bicyclists Cycling Instructor and member of the Bicycle Technical Committee of the National Committee on Uniform Traffic Control Devices. These comments are based on his observations during a field trip to examine bicycle facilities in New York City in December of 2008.]

Broadway bikeway, Manhattan

Broadway bikeway: clogged with pedestrians

For me, the pedestrian conflicts on a new unconventional Manhattan bikeway — on the pedestrian-enhanced blocks of Broadway starting south from Times Square — rendered that bikeway nearly useless — even though those blocks of Broadway are similar to the
9th Avenue layout in several ways:

  • Both streets are multi-lane one-way-southbound
  • Both have a left-curbside one-way bikeway
  • At intersections there is a bike signal and a left-turn pocket and turn-arrow for motor vehicles (where the cross street is two-way or one-way-left) Continue reading

Guest posting: John Ciccarelli on the NYC 9th Avenue bikeway

New York's 9th Avenue bikeway at 29th Street

New York's 9th Avenue Bikeway at 29th Street

Manhattan’s 9th Avenue bikeway, extending from 31st Street to 14th Street, is mostly a signalized left-curbside one-way on-street path, separated over most of its length from mixed-flow travel lanes by an in-street car parking lane. A couple of blocks near the end are separated only by a striped median or a single stripe. The barrier separation is the first of its kind in Manhattan but as is usual with bike lanes on Manhattan’s one-way avenues, the 9th Avenue bikeway on the left side — for two reasons:

a) Buses, which run frequently, use and stop in the rightmost lane of this multi-lane one-way street

b) Truck deliveries and taxi pickups/dropoffs occur in the rightmost lanes

Those activities are impractical on the left side of 9th Avenue on the bikeway blocks because the bikeway is separated from the rest of the Avenue by a left-side in-street parking lane. Continue reading