Citation

Shilling F, Waetjen D. University of California at Davis, Road Ecology Center. Davis, CA USA: University of California at Davis, Road Ecology Center, 2020.

Copyright

(Copyright 2020, University of California at Davis, Road Ecology Center)

The full document is available online.

Abstract

Using observations of reported traffic incidents in our real-time “California Highway Incident Processing System” (CHIPS), the Road Ecology Center has estimated the reduction in traffic incidents on state highways and rural roads that has resulted from the Governor’s “shelter in place” order. We estimate that since the order went into effect, collisions and especially injury and fatality collisions have been reduced by half, from ~1,000 collisions and ~400 injury/fatal accidents per day to 500 and 200 per day, respectively. We also found that animal-related incidents did not experience the same reduction. We found that traffic volumes were up to 60% lower on certain highways after the order compared to a similar period prior to the order, which may account for the reduced number of collisions. We highlight collision and injury/fatality hotspots on California highways since the shelter in place order went into effect and for a similar period in 2019. All data were derived from California Highway Patrol incident reports. This report includes maps of incident hotspots, and discusses this unexpected benefit of the shelter in place order.

This report and other tools are available on the Road Ecology Center website:
https://roadecology.ucdavis.edu.