Bicycle and Pedestrian Level of Service
September 12, 2016 Leave a comment
Level of service (LOS) is a term used by transportation engineers to assess the quality of a roadway. It typically measures vehicle speed and the amount of delay at an intersection and assigns letter grades A through F, A being a road where “Traffic flows at or above the posted speed limit and all motorists have complete mobility between lanes,” and F being a road where “Flow is forced; every vehicle moves in lockstep with the vehicle in front of it, with frequent drops in speed to nearly zero mph. A road for which the travel time cannot be predicted.”
What you don’t see here is any accommodation for anything that isn’t a car. In fact, since things like narrower lanes and long pedestrian signal times tend to slow down vehicular traffic, there is often an inverse relationship between pedestrian safety and vehicular level of service.
As such, there have been several proposals for how to measure pedestrian and bicycle level of service. Some of these use measures of delay or the density of users in a given area that are similar to those used to calculate vehicular LOS, while others quantify aspects of intersection design that have a unique impact on bicyclists and pedestrians to come up with a score.
One of these measures that is supported by Smart Growth America is the Charlotte Department of Transportation’s Pedestrian and Bicycle Level of Service methodology. It measures eight intersection features for pedestrian LOS and six features for bicycle LOS. Features include things like crossing distance, signal phasing, corner radius, right turns on red, and crosswalk treatments.
As I was looking at this, I thought, wow, doing this for a whole city would take forever. And while that’s true, doing just one intersection takes less time than it takes to watch an old episode of The Gilmore Girls on Netflix, especially once you’ve set up a template that looks something like this. And once you’ve set up your template, it’s easy to start adding the data to a Google MyMap, like this.
And once you have a map, you realize that this could go a lot quicker if you could try and convince some strangers on the internet to help you do it. So I’m asking anyone who is interested in this sort of thing if they would like to work on a big project with me where we map pedestrian and bicycle LOS all across the country. You don’t have to be from Philadelphia, just work in your hometown or a place you’re familiar with. If you’re interested, message me on Twitter @DavidBMunson and I’ll share the map with you. If we can just get this thing started then we can start creating data about the quality of intersections for pedestrians and cyclists that could potentially help cities fix the problems we find and create a better world for all of us, backed up by data.