Some really interesting work from Denver, Colorado planners who tease out the relationship between street width and accident rates per passenger mile. Wide streets come out the winner with a high degree of certainty that it is in fact street width that is responsible for the increase in accidents. They removed data points on accidents when icy/wet conditions occur, substance abuse was party to the accident, and major arterial roads, as a way to eliminate other causes that would blur the relationship between width and accident rate.
They wanted to basically look at smaller streets that are in places where people live, work and recreate, not major transportation corridors.
For us planners, I think this means we should be working with our local public works department to accomplish the following:
1. Reduce Street Widths.
2. Align our zoning code to either allow narrow streets, or on-street parking with limited parking or parking maximums off-street.
3. Create roadway treatments that encourage slower speeds by reducing the width of the travel path. These would include bulb-outs, pedestrian islands, speed tables, on-street parking and host of other treatments.
Lots of options to make streets safer for people walking, cycling and in cars.