The High Risk of “Low” Speed Roads

I came across this interesting graph in a new report from the National Cooperative Highway Research Program, with the lengthy title “Guidance for Implementation of the AASHTO Strategic Highway Safety Plan Volume 23: A Guide for Reducing Speeding-Related Crashes.”

I was struck by the substantial percentage (the second-highest of all road forms) of speed-related fatalities on “low speed,” non-interstate roads. I am not sure what the percentage of pedestrian fatalities were, nor the speeds of impact involved (something would be far from exact in any case), nor do I (or anyone, really) know the exact differences in exposure for driving on local roads versus high-speed highways.

But I took the figure as a sign of what sort of issues were at stake in things like the recently mentioned Prospect Park West Road Diet (in Brooklyn), which now seems to be moving forward.

This entry was posted on Monday, April 20th, 2009 at 7:19 am and is filed under Roads, Traffic safety. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.

6 Responses to “The High Risk of “Low” Speed Roads”

  1. Justin Horner Says:

    I’d check into the rate of fatality for each facility. If 29% of all traffic is on low speed non-interstates, than 29% if all fatalities is perhaps not so high of a number.

  2. acline Says:

    From no more information than what’s in this chart, my first thought is that the results make sense. Speeding in low-speed environments is probably the same as speeding in complex environments, i.e. roads with a lot of cross traffic, driveway entrances, sidewalks, etc.

  3. Tom Vanderbilt Says:

    These are both valid points. I suppose my interest was less about the exposure rate per se than in the qualitative aspect; i.e., that these low speed, presumably safer roads are home to such a large portion of the fatalities related to speeding (which makes me wonder if enforcement efforts shouldn’t be shifted a bit towards these roads, away from Interstate highways and the like).

  4. Bob Bigboote Says:

    Federal Highway Adminstration states there are a total of 4 million miles of roads in the U.S. with only 47,000 of them being Interstate. From a law enforcement perspective, the interstates are a better use of resources to reduce the fatality rate.

    To make a significant impact on the remainder of the roads would require a massive increase in law enforcement resources to achieve reasonable coverage.

  5. Justin Horner Says:

    Using Bob’s numbers, don’t we get 0.037 fatalities per mile on interstates and 0.002 fatalities per mile on non-interstates? That leads to the opposite conclusion.

    I wouldn’t be surprised if we found lower accident rates on interstates; but when you do get an accident there, ya die!

  6. aaron Says:

    Not so sure about speed upping the fatality rate. I mean, seriously, what percentage of driving is done below 55mph on the interstate. It seems, just like the economy, slow kills.

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