Learning from Bologna’s off-street bicycle network: tolerance, safety, thanks | streets.mn

At streets.mn, I have the following post: Learning from Bologna’s Off-street Bicycle Network: Tolerance, Safety, Thanks, complete with a vivid three minute video from the user perspective of the cyclist.

“The characteristics of a city’s off-street cycling network vary widely by culture. Expectations are adjusted accordingly. The most progressive cycling communities in the U.S. have set  high standards for what they consider to be suitable bicycle facilities…”

National Academies of Engineering, Frontiers of Engineering – the Future of Transportation

This past weekend I was at the US-EU Frontiers of Engineering Workshop in Paris. The National Academies of Engineering asked me to co-chair the session on “The Future of Transportation.” Three researchers who are well known in the U.S. dazzled the collection of 50+ other engineers who represented other engineering fields.

Why Traffic Management Works…And Why Coordinated Traffic Management will Work Even Better
 – Serge Hoogendoorn, Technical University Delft, The Netherlands

Nash-Stackelberg Games in Transportation Networks: Leveraging the Power of Smartphones for Traffic Monitoring and Management
 - Alexandre Bayen, University of California, Berkeley

Impacts of the Sharing Economy in Transportation
 - Kari Edison Watkins, Georgia Institute of Technology

Here are two observations based on the session:

1. The last speaker, Prof. Watkins, offered several perspectives in the her presentation that got most of the Q & A session talking about issues of how to harness car travel; there was even a focused discussion about the role of cycling in all of this. Yes, some of the world’s brightest engineers were talking specifically about spurring more cycling as part of our transportation system for almost 15 minutes  (really, I had little to do with this).

2. A key element of Watkins’ presentation stressed elements of the “shared economy” and implications for transportation—in terms of sharing space and information.

For us transport folks, there are seemingly endless implications of the shared economy. One framework might be to approach this by thinking about different elements of non-auto using behavior vis-à-vis different considerations that are important for adoption.

Different elements of transportation and transportation information, of course, include: Transit information (e.g., when is the next bus), Bike and Car sharing (e.g., where are the stations), Cycle tracks (e.g., how do people use the network), Ride sharing or slugging (e.g., sharing space in a conventional car), Destination knowledge (e.g., where is the closest pizza)…the list can go on.

Considerations that are important for adoption would include:

-Are there general safety fears of the transport device being used (e.g., am I using someone else’s car whose brakes don’t work)?

-Are there specific safety and security fears with procuring access to the transport device (i.e., do I have to meet someone I don’t know to get a hold of the device)?

-Are you concurrently sharing a physical space with another person (e.g., sitting shotgun in their car)?

-How much reliability of the trip is needed (e.g., you absolutely need to get there now)?

-To what degree can the information exchange be public, done via open wiki or otherwise open source?

-To what degree would my anxiety about sharing space (e.g., a spot in their car) be overcome via forms of social media (e.g., leveraging facebook and 6 degrees of separation.

…the list can also go on.

The main point: to successfully leverage all the different forms of the shared economy for transportation, different forms of transport information have different criteria to “make it work.”

Diminishing returns of off-street bicycle facilities | streets.mn

At streets.mn, I have the following post: Diminishing returns of off-street bicycle facilities.

“Some attention to my previous post seemed to stem from the incredulity of implying anything negative about the Midtown Greenway—one of America’s most beloved darlings of a bike path […]“

Eyeing two unintended outcomes of the bicycle facilities arms race | streets.mn

At streets.mn, I have the following post: Eyeing two unintended outcomes of the bicycle facilities arms race. 

“In less than a decade, the Minneapolis Midtown Greenway (Minnesota) has quickly risen to one of America’s most beloved darlings of a bike path[1]. Similarly, the short stretch of the Cedar Lake Trail to the Twins Stadium provides much needed closure over an important stretch for cyclists in downtown Minneapolis. Both are critical assets for […]“



A Flying Pigeon in every household

…continuing the recent history theme, this time in China…

Owing to sheer numbers, nowhere else in the world has cycling played such a prominent role as in China. The important position the bike plays in this country can be traced back to April 1949 when Chairman Mao’s heir apparent, vice president Liu Shaoqi, visited a bike factory in Tianjin, 100 km south of Beijing. Shaoqi reportedly commanded that this Tianjin factory become the first bicycle manufacturer in New China[1]. With bicycling now an “approved form of transport” the nation quickly became zixingche wang guo, the Kingdom of Bicycles.

The bike was now one of the three “must-haves“ of every citizen, alongside a sewing machine and a watch—essential items in life that also offered a hint of wealth in dour times. Cycling use increased into the 1960s and 1970s and the Tianjin factory became the predominant bicycle manufacturer in the country. To the tune of up to 10,000 per day[2], the factory rolled out a model called the “Flying Pigeon,” a label that soon was used synonymously to refer to almost all bicycles in the country. The model was a sturdy all-steal colossus that looked as if it would last a lifetime. It was available in only one color, black (reminiscent of Henry Ford’s model T’s). It became a symbol of an egalitarian social system that promised little comfort but a reliable ride through life[3]. After all, it did come with a sprung real leather saddle.

These factory bikes became so ubiquitous that Deng Xiaoping, the post-Mao leader who launched China’s economic reforms in the 1970s, defined prosperity as “a Flying Pigeon in every household.” (The phrase vaguely reminds me of Herbert Hoover, in his presidential campaign, promising Americans a “chicken in every pot and a car in every garage.”) Over the years, the “Pigeon” humbly assumed its role as one of those few nostalgia-inducing artifacts of China’s postrevolutionary era, a period darkened by the Cultural Revolution and intense poverty”[4]. In 1994, China’s National Administration Bureau of Industry and Commerce named it a “national key trademark brand under protection,” enshrining the “Pigeon” as a national treasure[5].

[1] Approved form of transport: www.flying-pigeon.eu/historia.htm

[2] Rolling out 10,000 pigeons per day, see: http://empirecyclery.wordpress.com/2011/09/29/the-cult-of-the-flying-pigeon/

[3] The pigeon’s role in social egalitarianism, see: www.en.wikipedia.org/wiki/Flying_Pigeon

[4] The pigeon as a nostalgia-inducing artifact, see: www.bicycling.com/news/featured-stories/flight-pigeon

[5] Enshrining the pigeon, see: www.bicycling.com/news/featured-stories/flight-pigeon

1896 California bike map

Following yesterday’s post which showcased bicycling’s heyday around 1900, here is a 1896 bicycle map from California with aggressive cycling related advertising around the borders. And, it is interesting to see that more than 100 years ago, the same system of good, fair, poor was employed to rate the roads.

Tracing’s bicycling’s resurgence (in the U.S.) almost a century later

In the bowels of the Library of Congress in Washington, D.C. there are several photos of John D. Rockefeller. He was, after all, the richest man in America in his time, and one of the first major tycoons. In a full size 1913 portrait you find him gently smiling next to his shaft drive bicycle[1]. Second only to golf, cycling was a primary leisure activity for Rockefeller. Rather than walk the golf course during his later years, he reportedly mounted a bicycle to allow caddies to help push him[2]. Seeing world’s greatest oil tycoon juxtaposed with a bike—the travel mode that, in that in current-day dialogue prides itself as being oil-free—is ironic. Rockefeller’s participation in cycling is emblematic of cycling’s “golden age” during the decades before and after the turn of the twentieth century.


Starting with its popularization in the mid-1880s, bicycle technology quickly progressed worldwide. In the U.S., Albert Augustus Pope commandeered the bicycle industry by storm via mass production[3]; the original “boneshaker” and “high wheeler” models morphed into the “safety bicycle” and American factories were producing two million of them per annum[4].


The improvements and availability of the bicycle timed perfectly with the women’s emancipation movement in the U.S. The safety bike provided women with unprecedented mobility and personal freedom. Cartoons of the day drew depicted women becoming so attached to their bicycles that they neglected their “traditional duties.” The independence that bicycle travel provided spurred one of cycling’s most enthusiastic endorsements, hailing from Susan B. Anthony, “Let me tell you what I think of bicycling. I think it has done more to emancipate women than anything else in the world.”


Cyclists still had to push elbows, not with cars, but rather with the antagonism from horsemen, wagon drivers, and pedestrians. Rutted roads of gravel and dirt posed other challenges. Improving riding conditions to enable cyclists to relish in their newly discovered sport became a priority; subsequently, more than 100,000 cyclists from across the United States joined the League of American Wheelmen to leverage their collective strengths. The league claimed Rockefeller as a member and to this day, they celebrate him as one of their most famous. Near the end of the roaring twenties, The Nation ran an article “An Echo of Wheels.” It talked of an era when “the world was awheel, men, women, and children” and “every town had a bicycle club”[5]. Cycling was, at no other time in history, at the top of its game.


Relegated to toy status


However, Black Tuesday eventually struck and cycling’s climb out lacked staying power. Here’s how the stage was set, at least in the U.S., for cycling’s largely forgotten status over the next century. Here’s why the status of the bicycle was quickly relegated to being little more than a children’s toy.


By 1918, Henry Ford was rolling a Model T off the assembly line at an unprecedented rate, every fifteen-minutes[6], allowing the commoner to gather a car with four months worth of paycheck. More than a dozen U.S. Housing Acts spread over the 1930’s, 40’s, and 50’s made it easier than every before to buy the pristine suburban home[7]. Dwight Eisenhower, while serving as Supreme Commander during WWII witnessed the Autobahn in Germany and recognized its military value; upon assuming Presidency, he helped marshal resources for the U.S. to build a comparable system. Coupled with policies in 1949 to stimulate “urban redevelopment,” later broadened in 1954 to “urban renewal,”[8] monumental changes were taking place in cities. Focus was on anything but bicycling.


Transportation planning priorities


Priorities for various transportation planning followed suit[9]. The 1950s created the institutions and the financing mechanisms needed to greatly expand transportation infrastructure[10]. Efforts in the 1960s focused on the largest single public works program in the history of the world, the U.S. Interstate Highway System. The 1970s version of the Clean Air Act focused on mobile sources, namely the environmental costs of cars. Efforts to beef up public transport received a large nudge. Not surprisingly, transportation planners in the 1980’s were vexed with suburban congestion. They subsequently spent time chasing relatively less expensive strategies based on travel system management and travel demand management. These notions were broadened to growth management and concurrency, the buzzwords in the 1990’s.


The landmark Intermodal Surface Transportation Equity Act (ISTEA) of 1991, for the first time, gave a nod to intermodal transportation policies and granted new powers to Metropolitan Planning Organizations. Funding became available for bike paths and cities began enrolling the services of the token bike planner. For cycling specifically, the passing of ISTEA was analogous to a terrier circling your ankles yapping for attention, “Look at me, I’m environmental, inexpensive, good for the lower class, and healthy.” What amounted to probably a dozen bicycle plans in the early 1990s blossomed to hundreds within the decade. But efforts continued to be largely steamrolled by engineering departments or other standard practices. Ambitious, goal-heavy non-motorized plans were relegated to the proverbial status, “sitting on the shelf collecting dust.” Pro-cycling arguments were not so much disregarded wholesale; they just were not considered to matter.


Acute criticism at the time articulated cycling a fringe mode[11] whose purpose was mainly for social and recreational activities and its use in cities was limited owing to heightened crime rates; subsequently, bicycling’s ability to become a “player” in mainstream transportation circles was limited[12]. There were bigger fish to fry. The turn of the century witnessed a declining federal role and subsequently fewer resources. There was an increased focus on maintenance, managing roads via Intelligent Transportation Systems, and fixed system transit forms of streetcars and transit oriented development.


Climate change and a recession


A few years following the turn into 21st century, two things collided for transportation, generally speaking, and bicycling, specifically. First, the wears that climate scientists were pedaling were increasingly gaining currency. Both the scientific community and popular culture became fixated on climate change. The famed “hockey stick graph,” showing a spike in temperatures in the Northern Hemisphere since the beginning of the Industrial Revolution, gained endorsement from the Intergovernmental Panel on Climate Change. Transportation was targeted as a major contributor to greenhouse gas production; cars were primary culprits. A rally cry was out.


Second, the Great Recession yielded fewer resources and diminished transport demands. Focus shifted to cutting back on the transportation building agenda; it became more important to intelligently manage a decline in transport demand. Combined, the increased global attention to greenhouse gas emissions with a need to and manage a decreased demand for transport provided a powerful, and organizing narrative for urban planning in the 21st century. The narrative provided an increased role for bicycling that appears to be much welcomed.


In recent years, bicycling has received a stiff wind of support from many walks of life that has catapulted it into the forefront of discussions about transport and cities. Just as the British Crown required a cathedral for a community to achieve “city status” in medieval Britain, any present day city worth their weight in salt seems to want to include bicycling in its portfolio. Mayors in cities of all sizes are actively engaged in a national “arms race” to make their town the “best” bicycling city in the country[13]. And, these cities appear to need a bikesharing system to boot. In five years since 2008, the number of worldwide bikesharing systems increased from 213 to 535[14]. Politicians found that catering to bicycling is synonymous with being “hip;” being “hip” is seen as being friendly to start up businesses; start up businesses stimulate economic development in a post recession period[15]. Companies are increasingly weaving cyclist’s needs into their designs for new developments[16]. Not one, but three powerful national organizations now exist in the U.S. to advance cycling issues and lobby for their efforts[17]. The previously innocent bicycle has even “come of age” in another dimension surrounding security. In Kolkata (India), the assistant traffic commissioner of police reported that the city is banning bicycling on key corridors citing security concerns: “bicycles are often used to plant bombs”[18].


Trends in research activity also following suit. The Transportation Research Board (TRB), one of six major divisions of the National Research Council, is the primary worldwide outlet for such. In the early 1990’s, their database spit back around 30 papers per annum on bicycling; by 2012, this number surpassed 200[19]. Over the past two years, researchers from more than 80 papers have applied to present their cycling findings at TRB’s annual meeting; 20 years ago you could count the number of people wanting the same on one hand[20].


Even pop singers (I am thinking of David Byrne of the Talking Heads) have passionately published books about cycling in cities. My own New York Times news alerts (keyword: bicycling) now notifies me of several stories week compared to one a month a few years ago. Even its fashion section runs specials on cycling oriented shoes, pants, earings, helmets, and other accessories.


The sociologist Quentin Bell is largely credited as being the first to identify cycles in the fashion industry[21]. Some fashions take short time to peak; others longer. Fashion cycles tend not follow measurable time tables. A rise of bicycle activity at two points in time separated by a century hardly comprises a cycle. But its recent rise in popularity begs the question if it is a fashion. The following is more certain: the formerly yapping terrier now resembles a mature dog with hopeful eyes as its owner prepares to throw the frisbee.

[1] Shaft drive bikes were employed as an alternative to using a chain. But owing to decreased mechanical efficiency and higher cost, its widespread use was limited.

[2] Ron Chernow (1998). Titan: The Life of John D. Rockefeller Sr. (Random House)

[3] Albert Augustus Pope, see ‪Bruce D. Epperson (2010). Peddling Bicycles to America: The Rise of an Industry. McFarland and Company.

[4] Two million per year, see: http://www.forbes.com/sites/tanyamohn/2012/06/25/a-comic-look-at-the-1890s-bicycle-boom/2/

[5] For an “Echo of Wheels,” see: http://thenation.s3.amazonaws.com/pdf/anechoofwheels1931.pdf

[6] Model T’s coming off the assembly line, see: Georgano, G. N. (2000). Vintage Cars 1886 to 1930. Sweden: AB Nordbok.

[7] Kenneth T. Jackson’s (1985) book, Crabgrass Frontier: The Suburbanization of the United States, is arguably the best account of this phenomena.

[8] Redevelopment to renewal, John T. Howard, The Role of the Federal Government in Urban Land Use Planning, 29 Fordham L. Rev. 657 (1961).

[9] The following transportation planning priorities were arrived at via useful email exchanges with David Levinson (University of Minnesota) and Brian D. Taylor (University of California Los Angeles) on October 11, 2013.

[10] The Highway Revenue Act was passed and the Interstate Highway Act was out of the starting blocks.

[11] Gordon, P. and H. W. Richardson. Bicycling in the United States: A Fringe Mode. Transportation Quarterly, 52(1), 1998, p. 9–11.

[12] Granted, the author’s perspective was largely based from Los Angeles, not exactly the bastion of supportive cycling environments, but many of the points made sense.

[13] Such claims have been recently documented to come from mayors in Seattle (Washington), Chicago (Illinois), Minneapolis (Minnesota), Long Beach (California), Portland (Oregon), Boulder (Colorado), Chattanooga (Tennessee), just to name a few.

[14] There were reportedly 213 systems operating in 14 countries with 73,500 bicycles in 2008. This climbed to 535 systems in 49 countries with 517,000 bicycles, see: http://en.wikipedia.org/wiki/List_of_bicycle_sharing_systems

[15] Synonymous with startups, see: http://www.triplepundit.com/2013/10/bike-loving-mayors/

[16] Cyclist’s needs being recognized by developers, see: http://www.bizjournals.com/seattle/news/2013/06/21/commercial-real-estate-developers.html?page=all

[17] In February 2012, the three largest bicycle advocacy organizations in the US—consisting of the League of American Bicyclists, the Alliance for Biking & Walking, and Bikes Belong (henceforth labeled PeopleForBikes)—issued a communiquéabout their intention to unify and become one organization with one board of directors[17]. Discussions have since broken down and each exists but with intent to leverage collaborative opportunities.

[18] Bikes used to plant bombs, see: http://www.ibtimes.com/no-ticket-ride-kolkata-india-bans-bicycles-reduce-traffic-congestion-terror-threats-1412820

[19] Email conversation (21 October 2013) with Ralph Buhler, chair of TRB’s committee on bicycle transportation: “A search for the term ‘bicycling’ in the Transportation Research Board’s TRID database yields an annual average of 29 peer-reviewed papers, government reports, and other published ‘gray’ literature between 1990 and 1992. The annual average rose to 64 between 1999 and 2001, and jumped to 212 for the years 2009-2012. Thompson’s Web of Science focuses more narrowly on peer-reviewed academic journal articles and shows an increase from an average of 1 peer-reviewed paper per year including the terms ‘bicycling, transport/transportation, and travel’ in 1990-1992 to 44 in 2009-2012.”

[20] Email conversation (21 October 2013) with Ralph Buhler, chair of TRB’s committee on bicycle transportation: “The number of papers submitted to the bicycle committee of TRB increased from about 3 in the early 1990s to approximately 15 in the early 2000s and roughly 80 papers for each the 2012 and 2013 annual meeting, placing it among the top tier of all TRB committees.”

[21] Quentin Bell noticing a cyclical flow in dress change in Western society since at least the thirteenth century, see: On Human Finery: The Classic Study of Fashion Through the Ages. Allison & Busby (originally 1976)


The paths that people take (5 part series)

As part of an interesting FIVE part series focusing on different considerations in the paths that people take for travel (i.e., why is it not always the shortest?), the Transportationist discusses our bicycle route choice experiment.

Why reduced congestion is a weak argument for cycling

In 1991 the City of Münster (Germany) aimed to raise support for the city’s spending on bicycling infrastructure. The press office of the city made a poster comprised of three panels. Each panel’s background displayed Münster’s Prinzipalmarkt, the cobblestoned main street in town; what differed in each panel was what filled the Prinzipalmarkt. The first depicted what the street looked like if 72 people were transported by car; the second, by bus; the third by bike. The main point was that bicycling is an extremely efficient way to use limited transport space in cities.

Twenty years later, Indian-based organization, Earthian, posted the figure to Facebook. It quickly went viral[1]. The graphic has since been used prominently in presentations worldwide to advance the arguments that bicycling is a strategic means of transport; bicycling can help reduce traffic congestion. In theory, it makes sense. And, the “reduced congestion” argument is one of the more prevalent ones in the advocate’s arsenal. It carries water for places with exceptionally high cycling use or for specific corridors. The argument, however, is fatally flawed when applied to larger units of geography.

The source of the substitution

The implicit assumption in the reduced congestion argument is that there is a substitution effect between a cycling trip and a vehicle trip. If true, it is helpful to consider the source of the substitution and its magnitude. For example, using mode share figures based on the US, a starting point suggests bicycling would draw from other modes in proportion to their current mode shares[2]. Bicyclists would therefore draw roughly 85 percent of their market from driving trips (solo or with others), 10 percent from walking trips, and the remaining from transit or other[3]. If most converters would come from existing transit users, a reasonably safe assumption but a population whose travel comprises a meager two percent of travel (again, in the US), then these numbers are relatively small. Tapping into the mindset of converting auto users presents a greater challenge.

The magnitude of the substitution

Understanding the magnitude of the substitution effect is difficult mainly because it is based on a counterfactual condition (e.g., if Booth would not have killed Lincoln, then…). There are two ways to think about it. One can start with a fixed number of vehicle trips and assume a share of those trips that are replaced by bicycling. Alternatively, one can consider the number of bicycle trips and estimate the share of these trips that replace driving. The two analysis strategies are not comparable.

Our own work found a wide range using the later approach, ranging between 25 and 68 percent of bike trips claiming to substitute for car trips[4]. This suggests that half of the existing bike trips, were they not by bicycle, would be by car. Such rates of substitution, I presume, vary wildly across the globe. Then think about places where cycling comprises more than half of all trips: Groningen (the Netherlands), Münster (Germany) or Copenhagen (Denmark). It is hard to conceive of the character of these iconic bike-friendly cities if most trips were by car. Most bike trips substitute and the congestion savings is remarkable. But outside of these select settings, it is hard to know. In the rest of the world, if the logic is applied to a particular corridor, the congestion savings argument might have a noticeable impact.

Vehicular travel is not fixed

For most cities, there is a there is an inherent fatal flaw with the foundations of the above logic. These flaws become apparent when congestion is considered on a larger scale or for places that are growing (the birth rates in the above mentioned towns are not exactly skyrocketing). The foundation assumes a fixed demand for travel, and vehicular travel in particular. Prevailing trends of population growth and auto ownership suggest otherwise. Coupled with what is generally known about travel behavior, and driver behavior more specifically, these factors paint a meager picture for cycling’s ability to address congestion.

Traffic congestion is a problem is that is both old and complex. Rome struggled with it, resulting in Caesar simply issuing a ban on carts and chariots back in the day. Things aren’t that easy in most cities and more recent thinking has focused on its source and solutions. A good portion of that thinking is framed around issues of capacity: building more roads or widening existing roads and what is referred to as the effects of induced demand[5]. Any form of relief provided for drivers, the story goes, will quickly be gobbled up[6]. Drivers will defect to the corridor where the relief is offered. Other drivers, previously sleeping in and starting their commute at 9:30 will join the 8:00 am rage. Still others who were previously carpooling or using transit, learning that their route is as bad as it used to be, will switch to driving. Add traffic from the inevitable new development down the street and any immediate gains become a wash.

A key outcome from most of this thinking has been coined the “Iron Law of Congestion,” suggesting that once congestion has reared its ugly head in a city, there is little the city can do get rid of it. Congestion is largely an inescapable condition in all large and growing metropolitan areas across the world.

The same logic applies to gains from getting more people on bikes; it might provide temporary respite which would be gobbled. Suppose a community cycling initiative can leverage the previously explained phenomena to the fullest. Transit users and car users alike convert to bike travel for most trips. Getting more people on bikes might mean less people driving cars; it might mean temporary relief in the previously congested corridor. But using the Iron Law and considered across the region, the effects on congestion would be futile.

Congestion is less about capacity

But that’s not all. Driver behavior is also a culprit to congestion. Tom Vanderbilt’s book, Traffic, climbed its way to become a top ten best seller on the New York Times list in August 2008. It is the only book focused on transport that has claimed such a coveted spot. One of Vanderbilt’s principle claims is that traffic congestion has more to do with driver behavior than capacity issues. Drivers switch lanes, rubberneck, merge too early or overcompensate when braking—all relatively small flaws in driving behavior—but in the aggregate, they have a major impact on congestion.

Such driver errors and their consequences on congestion will diminish over time; automated vehicles will likely clean up such mishaps. However, this stream of thought suggests congestion has less to do with overall capacity in general. Even further evidence of the importance of the operations of a system in terms of congestion comes from New York City’ recent experience. Over the past years, the city has been aggressively reallocating select street space for cyclists and pedestrians, thereby decreasing overall vehicular capacity. Analyzing taxi cab logs, however, the Bloomberg administration contends that travel speeds have remained steady despite such decreased real estate—an outcome that is largely attributed to improvements to the city’s traffic signal system[7].

Larger fish

Cycling’s limits to reduce congestion is perhaps best understood when the argument is taken to an extreme. Scaling up to large and quickly growing cities, the latent demand ready to consume any relief to existing congestion is overpowering. Projections from the United Nations paint a picture of adding more than one million people to the earth every five days for the next dozen years[8]. Admittedly, the majority of this growth will be absorbed in cities of developing countries and its impact being unequally distributed and perhaps even barely felt in Europe. But with rising incomes generally across the globe, the more than 60 million cars that are produced each year (more than 100 new cars every minute) will likely find willing drivers[9]. The primary drivers to congestion (pun intended) are more powerful than anything that bicycling can realistically impact over the next decade or two, globally speaking.

There might be good reasons to spur bicycling and build more facilities to do it. The congestion relief might be felt locally. Aiming to reduce congestion on a regional level, however, is one of the least reliable rationales for doing so. Cyclists are better off making hay from other, more reliable arguments.

[1] http://news.medill.northwestern.edu/chicago/news.aspx?id=190533

[2] Transport econometricians refer to this as the principle of Independence from Irrelevant Alternatives (IIA)

[3] Summary of Travel Trends: 2009 National Household Travel Survey, http://nhts.ornl.gov/2009/pub/stt.pdf

[4] Piatkowski, Dan, Kevin J. Krizek, and Susan Handy (2013). Accounting for the Short Term Substitution Effects of Walking and Cycling in Sustainable Transportation. Working paper available from the Active Communities / Transport (ACT) Research Group.

[5] Most of the original research is attributed to David Lewis [(1977), Estimating the influence of public policy on road traffic levels in greater London. J. Transport Econ. Policy, 11, pp. 155–168] and Martin Mogridge [(1990),Travel in towns: jam yesterday, jam today and jam tomorrow? Macmillan Press, London].

[6] Anthony Downs is largely credited with popularizing some of predominant thinking, starting with his 1992 book, Stuck in Traffic: Coping with Peak-Hour Traffic Congestion (1992), The Brookings Institution: Washington, DC. The concept is better explained in his updated work a decade later, Still Stuck in Traffic (2004), The Brookings Institution: Washington D.C.

[7] See, for example, http://www.nytimes.com/2013/09/05/nyregion/in-bloombergs-city-of-bike-lanes-data-show-cabs-gain-a-little-speed.html or other reports such as the “Green Light for Midtown Evaluation” (January 2010), from: http://www.nyc.gov/html/dot/downloads/pdf/broadway_report_final2010_web.pdf

[8] Population Division, United Nations, Department of Economic and Social Affairs. World Population Prospects: The 2012 Revision.

[9] Figures provided by the International Organization of Motor Vehicle Manufacturers, see: http://www.oica.net/wp-content/uploads/2013/09/total-production-2013.pdf

Professor, Environmental Design and Transport, University of Colorado