Hey, there! Log in / Register
That's a lot of crashes
By adamg on Sun, 11/28/2010 - 11:35am
The Boston Cyclists Union's Interactive Crash Map maps bicycle crashes between May and October of this year.
Via Boston Reddit.
Neighborhoods:
Topics:
Free tagging:
Ad:
Support Universal Hub
Help keep Universal Hub going. If you like what we're up to and want to help out, please consider a (completely non-deductible) contribution.
Comments
This is great. Clearly there
This is great. Clearly there are trouble spots which everyone needs to be aware of which is the first step toward improving safety.
Trouble Spots
This also shows where there needs to be an assessment of possible multi-modal engineering improvements as well. Possibly traffic calming, changes in light cycles, lanes and turn lanes for cyclists, etc.
What do you think is the % of
What do you think is the % of people hit vs the number of people riding during this period? Does this represent 10%, 20%, etc...
My guesstimate: 1-2% How I
My guesstimate: 1-2%
How I got there:
Boston's Annual Bike Report has traffic counts for a bunch of intersections. I interpret the description to say this is how many bikes went through that intersection in an hour at a busy time. Adding up the intersections gives ~7,000.
If you say there are two busy hours, that's 14,000
If you allow for people biking who don't go through those intersections and people who don't bike everyday, we'll say 20,000 cyclists in Boston.
There are 316 accidents on the report. So, 1-2%
That Sounds High
Thanks for taking a first shot at this - I really appreciate your transparency and attempts to put some data on this.
As a regular cyclist, I have to say that sounds really high. I don't see nearly that many accidents in my travels, although I try to avoid congested areas in favor of less traveled secondaries. Amongst my cycling friends, an admittedly experienced group, the accident rate seems to be one every four years or so - say, 1 accident/(4 years x 500 trips/year) = 0.05%. Maybe there's a big group of newbs having some accidents for us?
I think there are some issues with your information that you may not be aware of. If I recall correctly, the traffic counts were made in an off month - March or April. While they would properly estimate the change in traffic from 2007 to 2009, they would underestimate the traffic for the period over which the accidents were tallied. As a regular commuter, I know as well that there are at least four busy hours - 8-10 am and 5-7 pm - on a typical work day. Not much different from the busy car hours - just shifted a tad later.
I do appreciate your attempt to estimate here - with some discussion, I suspect we might tweak this to get closer to a less dire number, one more in tune with what us long-term users of the roadways experience!
You seem to be calculating a
You seem to be calculating a different number than me. Mine was percent of cyclists in an accident in the past 6 months. If you double it to 2-4% for a year, that says a cyclist can expect to be in an accident once every 25-50 years, much less frequent than the once every 4 years you've suggested.
Hmmm ...
Good point.
If you consider that these are accidents requiring emergency response (rather than limping to work and seeing a doctor later), then a 1/50 per year doesn't seem that far off.
I've had one emergency response accident in 25 years of cycling in the area.
Missing river bridges
There is just one accident reported at the intersection
of the three river bridges. Anderson, Western, and River St.
River St in particular is really bad. I wonder if there
aren't more because of the state vs city reporting situation.
worthless "data"
Half the reports I clicked on had absurd claims for cyclist speeds. One cited the speed as "17MPH". Really? Someone was standing there with a radar gun and clocked 'em right before the collision? Bullshit.
Every report I clicked on also listed the vehicle speed as "unknown", 0 MPH, or ">10MPH". Apparently, everyone in Boston drives like grandmotherly saints driving in cemeteries.
In one cast, a collision between a cyclist and a car described as a "TBONE" put the car's speed at 0MPH and the cyclist's at "40MPH".
I want to meet a)any cyclist from the area that is capable of getting themselves up to 40MPH and b)survived ramming into a car sideways at that speed.
Looking more closely now, I'm
Looking more closely now, I'm slightly concerned over the quality of the data as well.
The most publicized bike crash in recent memory was at the corner of Kelton and Comm Ave on August 9 ( http://www.bpdnews.com/2010/08/10/fatal-bicycle-ac... ). The only accident shown on the map at that intersection was July 6. I have no idea why it wouldn't be on the map.