California Car Collision Rates Decline After Shelter-in-Place Mandates

A hopeful forecast predicts that thousands of monthly traffic collisions will be avoided due to reduced vehicular travel during California’s shelter-in-place period.

1 minute read

April 9, 2020, 9:00 AM PDT

By Lee Flannery @leecflannery


Cars

Alexey Rotanov / Shutterstock

A U.C. Davis survey finds that auto collisions have been curbed by more than 50 percent since the stay-at-home orders went into effect around the state of California in March. "The survey suggests that a 60% drop in traffic volume — when compared with the same period last year — accounts for a roughly 50% decline in collisions on roadways policed by California Highway Patrol," writes Louis Sahagun. 

The U.C. Davis Road Ecology Center's "California Highway Incident Processing System," which tracks close to real-time traffic data in California, reported only 500 collisions in the period between March 21st and March 30th, a significant reduction from the 1,116 collisions observed in the ten-day period between March 10th and March 19th. The decrease in vehicle travel and traffic volume resulting from the state-wide order also correlates to a reduction in fatality and injury caused by collisions. 

Road Ecology Center co-director Fraser Shilling was unable to assess animal fatalities on public roadways, the main focus of his research, due to the lack of data in the short time period. Shilling hopes to center future research on "cost-savings and other social benefits from reduced injuries and deaths on state highways due to COVID-19."

Wednesday, April 1, 2020 in Los Angeles Times

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