Bluffton’s Main St. before streetscaping. (www.trafficsignal.com)
While campaigning for new crosswalk signs at the intersection of College and Main, I’ve leaned that most Bluffton residents would prefer a traffic signal at this location in front of our high school and public library. Yes, we used to have one….
Well, a new traffic study is in progress. Data was collected earlier in September and is under review by the Ohio Department of Transportation (ODOT) office in Lima. I’m hoping that the timing–in good weather, during a busy period for after school sports and library use–will prove to be a more accurate reflection of peak pedestrian activity than the last study.
While this is happening, I’d like to know why our common sense tells us something different than what ODOT sees. So I took a look at the calculations for the January 7, 2008 study and I asked friends to check the math. They noticed that adult walking speeds of 3.5 feet/second were used rather than student speeds.
So, I’m asking ODOT whether they can use a slower walking speed for the new study. My review of the Manual on Uniform Traffic Control Devices (MUTCD) revealed the following in Section 4E.06 Pedestrian Intervals and Signal Phases:
10 Where pedestrians who walk slower than 3.5 feet per second, or pedestrians who use wheelchairs, routinely use the crosswalk, a walking speed of less than 3.5 feet per second should be considered in determining the pedestrian clearance time. (See http://mutcd.fhwa.dot.gov/htm/2009r1r2/part4/part4e.htm.)
That certainly describes a school zone crosswalk where elementary, middle and high school students need to cross Main St. Since school has begun, I have also observed adults with slower walking speeds and individuals using motorized wheelchairs at this location.
Looking for additional information on walking speeds, I read an International Ergonomics Association study that showed student crossing times range from 2.0 feet/second for elementary students to 3.0 feet/second for high schoolers. (See http://www.iea.cc/ECEE/pdfs/art0217.pdf.)
I also wonder if ODOT has considered the delay and queue length for cars on College Ave., but I don’t have the heart to dive into “unsignalized intersection theory.” (See https://www.fhwa.dot.gov/publications/research/operations/tft/chap8.pdf.)
Readers, if you’ve stuck with me for this explanation, thank you! I know this is more information than most folks want to hear. Can we find a bridge between common sense and statistical analysis? Stay tuned for future updates!