Do Bike Lanes Affect the Proximity of Cars?

This picks up on a theme explored by Ian Walker, the Warrington Cycle Campaign, and others: A new study finds cars pass more closely to bikes on roads with cycle lanes.

The study, which is due to be published in the scientific journal Accident Analysis and Prevention, says that on roads without cycle lanes, drivers “consciously perform an overtaking manoeuvre”. On roads with cycle lanes, they treat the space between the centre line and the outside edge of the cycle lane as exclusively their territory and make less adjustment for cyclists.

The study concludes: “Cycle lanes do not appear to provide greater space for cyclists in all conditions.” The Highway Code tells drivers to “give cyclists at least as much room as you would when overtaking a car”.

I’ve not read the study yet, so I’ll reserve further comment — save for my own suspicions that the presence of paint can both increase driver awareness but also encourage them to stop thinking — but this brings up a whole host of interesting accompanying issues: Does that proximity lead to less safety, either real or perceived? Do the car speeds differ on either street because of the presence or lack thereof of cycle lanes? Do the cycle lanes lead to an increase in cyclists? Do cycle lanes lead cyclists to behave differently?

As a primer I recommend this essay, not to mention Jeff Mapes’ book Pedaling Revolution.

(thanks to Prashanth in London)

This entry was posted on Thursday, September 10th, 2009 at 11:01 pm and is filed under Bicycles, Cities. You can follow any responses to this entry through the RSS 2.0 feed. You can skip to the end and leave a response. Pinging is currently not allowed.

6 Responses to “Do Bike Lanes Affect the Proximity of Cars?”

  1. DLM Says:

    That cars would pass closer to bikes in a bike lane makes sense because now each vehicle’s space has been defined. The car driver assumes that the bike will stick to its area and so does not need to provide as big a buffer in case the bike swerves. I would assume two cars passing each other on a street without a center line would also give more of a buffer than when the line defines each vehicle’s space.

    The more subtle question is whether that is safer, more dangerous, or inconsequential. As with the often quoted study that showed that drivers will pass a bicyclist wearing a helmet closer than one without, there is the assumption that closer is more dangerous. Logical, but perhaps false. A driver who reacts differently to the road design or rider behavior can be assumed to see the rider. I would think that this largely means that closer is not really more dangerous. While I’m not aware of any data to support it, anecdotal evidence seems to say that drivers almost universally state that they “didn’t see” the bicyclist they hit. The fact that they see the bike rider means an accident is very unlikely, regardless of how closely they pass.

    Of course, more distance is safer, all other things being equal. But I don’t think the smaller distance can be used to argue against the safety of bike lanes.

  2. fred_dot_u Says:

    As an experienced and trained cyclist, I would dispute the phrase “safety of bike lanes”. Having segregated areas on the road for different road users results in less attention being directed where needed.

    It’s not the driver who passes a cyclist in a bike lane too closely that is the danger, it’s the driver who does not see a cyclist in a bike lane “because he doesn’t need to” that creates the danger.

    Bike lanes are statistically less safe, but provide a “feel-good” appearance. Lure them in, then kill them off would be one way of looking at it.

  3. Lee Says:

    the top priority of cycle lanes should be to get more people to use them, because you get a far greater increase in the safety of the individual cyclist by increasing the number of cyclists than by any other means.. in other words, a cycle lane/track that feels safe to use will be popular, hence it will actually become safer via safety in numbers. the best wayto make a bicycle lane popular is to create a physical barrier between the bicycles and the cars. Parked cars themselves make a great barrier. once a lane is popular, you can then use that popularity to push for more safety improvements – which ususally involves giviving more space from cars over to bikes.

  4. MikeOnBike Says:

    I think Lee sets a record for how many junk science suppositions you can fit into one blog comment.

  5. fred_dot_u Says:

    MikeOnBike, I had to read the post twice to recognize how many “popular” misconceptions are embedded in it.

    Just train the riders on safe cycling and they will ride. The numbers increase and everybody benefits without huge expenses in infrastructure modifications.

    “Oh, no, I’m already experienced enough at bicycling, I don’t need training”

    Okay, go ride your trails and stay off the road until you learn how to do it right.

    Well, I suppose the same could be said of motor vehicle operators too, eh?

  6. VEEGEEBEE Says:

    Paint=entitlement with brain in idle for cars and bikes.
    Staten Island has got to be the worst place in New York City for non-lycra-clad cyclists – and I know what I’m talking about, as a former midtown bike messenger (think: Quicksilver era). Bike lanes are just parking spaces or passing lanes to cars (worst offenders, btw, are police vehicles! although the Escalade drivers are pretty bad too, ’cause they think they’re “special”)

    Bike lanes usually are in the part of the roadway with the piping for storm sewers, street-house connections, etc. A cruddy surface, requiring lots of maneuvering. We also have lots of parallel grates. Well, the irregular cyclist – someone not following the same route every day – ends up with dinged wheels at best, physical harm at worst. Meanwhile, the car-drivers are confident that a bike lane means the bikes are going to stay in the lane. Recipe for disaster. And lets not even start on the hazards of car doors!

    I think bike lanes are a total waste of money.

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