Vehicular Cycling

On Wednesday, May 20th, Dennis Dumm was killed while riding his bicycle near downtown Minneapolis.  He was traveling north on Park Avenue, a wide, one-way street with a bike lane on the left side of the roadway.

On Wednesday morning, just as Dumm took off from the bike lane at the intersection of Park Avenue and E. 14th Street, a semitrailer driver began to make a wide left turn, crossing in front of Dumm and hitting and killing the 31-year-old cyclist.
Online discussion boards about cycling were full of questions from riders about how Dumm could have been hit when he was seemingly following traffic rules…
There is ongoing debate among traffic engineers, cycling advocates, and cyclists about whether bicycle lanes are actually the cause of many crashes – especially crashes like the one that killed Dennis Dumm.  The vast majority of cyclists favor the construction of new bike lanes and view it as an integral part of ensuring the safety of inexperienced cyclists while promoting new ridership.  However, there is a small but vocal minority of cyclists who oppose the construction of on-street bike lanes, arguing that they give cyclists a false sense of safety, that they repeatedly put cyclists in danger by encouraging them to ride on portions of the roadway where drivers aren’t likely to be looking for other vehicles, and that the conflict points created by crossing bicycle movements and vehicle movements defy the normal rules of logic that guide our driving when there are no bike lanes.  Instead, vehicular cyclists (as they are often called) argue that cyclists should integrate into normal traffic lanes with all other vehicles on the road.
The blog CycleSMARTDallas said this about Dennis Dumm’s death:
…this cyclist died because of a bad facility design, a design that defies the logical operation of road systems, one that set up the mechanics of this tragedy. The cyclist died because of the toy-vehicle mentality that believes magic paint segregation is the best protection for cyclists, as opposed to educated integration….

Had the cyclist been in front of the truck making the left turn (controlling his lane), the truck would have simply slowed down, waited for the cyclists to clear the intersection, and then turned. Because the cyclist was next to the curb on the truck’s right, he fell into the driver’s left-side blind spot. By segregating cyclists from other traffic, cyclists are too often removed from the environment that other vehicle operators function in. We become like pedestrians on the sidewalk… an under-viewed sideshow.
Determining whether the facility design is a contributing factor in the cyclists death is difficult.  It is true, of course, that if there were no bike lanes, there would be no crashes involving cyclists in bike lanes.  So if our objective is to minimize the total number of crashes in bike lanes, the easiest option is to simply remove the bike lanes, which is the option favored by vehicular cyclists.  However, while integrating cyclists into normal vehicle traffic would eliminate bike lane crashes, it is unclear whether a new type of bicycle/automobile crash would emerge in its place.  
I believe that every cyclist should know how to safely integrate him/herself into normal vehicle lanes.  Cyclists should be educated enough to know how to “control the lane” to ensure their own safety.  The educational programs initiated and supported by vehicular cyclists are valuable.  But to deny that there are inherent differences between bicycles and automobiles is foolish.  To encourage 15 mph cyclists to integrate into a roadway with a 40 mph speed limit is also setting the stage for crashes.  And it removes from both cyclists and automobile drivers the benefits of their chosen vehicles.  Drivers behind a cyclist lose the ability to accelerate quickly and arrive at a high top speed.  Cyclists lose the ability to bypass traffic congestion.
So here’s a thought-question: By extension of vehicular cycling logic, could we eliminate pedestrian deaths if we removed sidewalks and encouraged “vehicular walking?”  If this sounds completely ridiculous, if you think pedestrians are actually safer because of sidewalks, does the same logic apply to cyclists? Why or why not?

6 comments to Vehicular Cycling

  • Anonymous

    "So here's a thought-question: By extension of vehicular cycling logic, could we eliminate pedestrian deaths if we removed sidewalks and encouraged "vehicular walking?" If this sounds completely ridiculous, if you think pedestrians are actually safer because of sidewalks, does the same logic apply to cyclists? Why or why not?"

    This would not make sense because, in abstract terms, pedestrians operate by entirely different rules on public ways and cannot, by their nature, integrate with vehicular traffic. Peds can stop in a stride, instantly change directions and move sideways, and generally move much slower than vehicular traffic. Segregating them on sidewalks is, in general, fine and can improve safety particularly in darkness since they aren't required to wear reflective material or lights.

    Bicycles are bound by the same constraints as any other vehicle; they require stopping distance, they have a defined turning radius, they can reach speeds equal to or exceeding other vehicular traffic, etc. For these reasons cyclists are very compatible with other vehicular traffic and should position themselves laterally as appropriate for their speed or destination. Cyclists can operate by ped rules on sidewalks only if they ride very slowly and watch for crossing traffic at all side streets and intersections.

    The "separate" facilities, whether lanes or paths adjacent to streets, aren't really separate unless grade or signal separation is provided at any intersections or cross streets, which is rarely feasible and imposes either great cost or additional delay. All they do is separate cyclists from parallel direction traffic, and intensify, to varying degrees, collision hazards at intersections (where the majority of car-bike collisions already occur). Bike lane stripes can at least be ignored by cyclists that know better, but this unfortunate cyclist did not and followed this defective traffic control device to a tragic death by riding to the left of traffic that can turn left. The city that painted this bike lane stripe should bear most, if not all the responsibility for this accident. Really sad how this keeps happening, when will it stop?

    Portland, Or

    P.S.: Cyclists should also be educated to be extra careful around long vehicles (semi-trucks, buses, etc.); this is taught in most if not all motorcycle safety classes. Both cyclists and motorcyclists are easily hidden in blind spots and are susceptible to lane-changing sideswipes and turning collisions.

  • Ryan, thanks for commenting. I guess I'm not convinced that bikes are so similar to cars. Similarly to how you've described why peds are inherently different than both bikes and cars, I'd argue that the differences between bikes and cars is significant enough that integration doesn't always make sense.

    You describe how cyclists can operate on sidewalks following ped rules only if they ride very slowly. Does it also follow, then, that cars can integrate with bicycles safely only if they also travel slowly, or approximately as fast as typical cyclists? Some cyclists are hitting 20-25 mph. Plenty of us, though, especially the most inexperienced of us, top out around 12-15. How fast can autos travel before it becomes unsafe for a 15 mph cyclist to integrate and "take the lane?"

  • I've been contemplating bike commuting to work, but I keep hearing about all these bike-auto accidents…makes me nervous.

    I wish we could just build more trails, and not worry about bike lanes OR integration. *sigh*

  • Anonymous


    I'm studying transportation safety and I've also looked at all the major car-bike collision reports. Contrary to what many believe, there is little relation between speed and crash frequency. There is a relation between crash severity and motor vehicle speed, particularly for pedestrians (and possibly for cyclists). Also, the hit-from-behind crash consistently measures in the single-digit percentages of all car-bike collisions (and is usually a result of the cyclist not using a tail light or rear reflector at night); the vast majority occur at intersections (~90%), so improving intersections would be the ideal goal, but often it is not. The more politically correct approach of painting bike lane stripes or building sidepaths usually does the complete opposite, unfortunately.

    Cars and bikes can integrate really well in terms of safety (specifically crash frequency); what people might consider "dangerous" would probably be more accurately termed "uncomfortable", particularly for cyclists. For example, situations where, for safety, the cyclist has to take a narrow lane and auto traffic must change lanes to pass. Ideally these roads would widened to better accommodate the mix of slow and fast traffic and so cyclists can share the outside lane. Not always possible, especially in downtown areas. Bike lanes and paths can, to a limited extent, improve particularly difficult crossings. A bike path that goes over a high-speed merge is one example. A bike lane to the left of a right-turn-only lane can also be helpful.

    Where I live I regularly ride to a grocery store where I have to ride up a narrow 2-lane one-way street over a freeway overpass. On my school clunker, I'm probably going only about 10 mph. Every once in a while someone honks at me, but there I am, so they just go around me! Ideally the road would be wider, but there's simply no space so I just take the lane for my own safety. The couple of seconds of delay I impose on motorists is trivial, if anything.

    The speed differential between cars and bikes isn't really all that extreme when you consider all the other slow vehicles that regularly use the roads. I see motorists come to a complete stop in DT Portland to parallel park all the time, and I don't think there's been any problems with them getting hit. The few times I drive a car I get delayed by school buses, mail trucks, garbage trucks, transit buses, left-turning vehicles and farm tractors far more often than by cyclists. I can't even remember the last time I was delayed by a cyclist, it just doesn't happen very often. Even when I am, I've found they're the easiest slow-moving vehicles to pass. 🙂 Slow traffic is a part of the everyday traffic mix, but people see cyclists as just "different" for whatever reasons.

    I use to think how wonderful it would be to have grade-separated bike paths going everywhere, completely separated from traffic, flying over intersections and reaching nearly every I wanted to go. Then I realized that would never happen. When you think about, there just aren't very many places you can go without using public streets. Then you're pretty much left with the choice of integrating with traffic or riding by some mix of rules/principles that will necessarily put you in conflict with other traffic. That's how I see it at least. And my bike is just a human-powered motorcycle.


  • Sarah, don't be afraid. Choose your route wisely and ride assertively and you'll be fine – with or without bike lanes.

    Ryan, I think we would both agree that context plays a key role when deciding what sort of bicycle treatments to apply, if any. For example, we can both agree that on streets where bikes and cars should have similar operating characteristics, it is best for cars & bikes to integrate. No doubt, bike lanes on a quiet, local, residential cul-de-sac roadway would be a complete waste of money and introduce unnecessary complications for everybody. But I think our opinions start to diverge when we consider different types of roadways with increasing traffic speeds & volumes – or designs that won't permit a vehicle to pass a bicycle who has "taken the lane", or rush hours where traffic volumes in the opposite direction may not allow vehicles to pass.

  • I guess I have felt the same way as Sarah off-and-on for years, which has also kept me from cycling to work. Your response does give me more comfort, though, and also made me think: Am I any safer driving to work in my car than I would be cycling? I don't think so.