Vision Zero Speaker Series: Data Driven Decisions

On Tuesday July 28th we hosted the 3rd webinar in our Vision Zero Nashville Speaker Series. The focus was data, and how cities can use data to inform their Vision Zero Action Plans and all of their transportation decisions. Our speakers included Angela Berry, P.E., Traffic Safety Program Manager for the City of Charlotte's Transportation Department; Rolf Eisenger, Vision Zero Program Manager for Denver's Transportation Department; and Dr. Chris Cherry, professor at University of Tennessee Department of Civil and Environmental Engineering.

You can watch the full video recording of this webinar here, you can see the slides from our presenters here, and responses to the outstanding questions from the Q&A box are here

A few of our main takeaways from this webinar were:

  1. Data is an essential part of the Vision Zero programs in both Charlotte and Denver. In both cities, crash data was used to form a High Injury Crash network, to prioritize safety improvements. Both cities found that just 5-6% of streets accounted for the majority of traffic fatalities and severe injuries in the city. Here is Charlotte's High Injury Network, and here is Denver's.
  2. Denver uses a Equity Index to also ensure that traffic safety improvements can best serve vulnerable communities. This index includes factors including: older populations, car ownership rates, poverty rate, people with disabilities, children and schools, and socioeconomic information.
  3. Angela Berry from Charlotte, emphasized that the data alone only tells part of the story. Charlotte has an interactive map where people can submit safety concerns, and they have a Vision Zero task force to help guide decisions and provide input for what might not be reflected in crash data (near misses, etc)
  4. Angela Berry also shared how the High Injury Network doesn't just inform investments in her traffic safety program, but also is used to prioritize all transportation capital investments throughout the department of transportation.
  5. Both Angela and Rolf mentioned that their cities have Crash Investigation units -- which automatically go out to investigate traffic fatalities, and propose potential immediate countermeasures. Nashville does not yet have a interdisciplinary Crash Investigation team (outside of MNPD)
  6. Dr. Chris Cherry walked us through a case study that uses Nashville scooter data to identify safety risks. His research indicated that all fatal scooter crashes and most severe crashes involved car drivers. Only by addressing infrastructure will we be able to address safety concerns -- education only goes so far if there are not safe choices available to road users. 
  7. Dr. Cherry also discussed how scooters and bicyclists experience very similar crashes -- on similar streets, and at similar times of day. For both scooters and bicyclists, 80% of crashes happen at intersections, highlighting the importance of increasing visibility and protection for people on foot/bike/scooters at intersections, and slowing car turn speeds. 
  8. Finally our last takeaway was that the next realm for Vision Zero data is learning how to use data to predict crashes before they happen, rather than reacting once someone is injured and killed. This shift is a work in progress in many cities, but part of moving towards a safe systems approach. 

We are planning on hosting at least one more webinar in our series next month, the topic will be traffic enforcement. Stay tuned for details!