Highway Accident Comparison after Implementation of the San Pedro Bay Ports Clean Truck Program

Abstract

In an attempt to improve air quality, the Port of Long Beach (POLB) and Port of Los Angeles (POLA) implemented their joint Clean Truck Program (CTP) with stringent limits on the trucks allowed to dray containers from their terminals. As a result, many trucks serving the POLB were either banned or required expensive retrofitting to reduce diesel emissions. The POLA implemented similar restrictions along with an additional ban on trucks that are independently owned and operated. Accordingly, the CTP reduced the number of independent owner operators providing drayage services at these ports. Independent owner operators fall under criticism for being more dangerous than other commercial truck drivers. Some argue that fierce competition and thin profit margins lead them to drive more aggressively and cut corners when it comes to safely maintaining their trucks. This study investigates whether the CTP impacted safety on highways surrounding the POLB and POLA. Weekly accident and traffic data from highways carrying heavy drayage traffic, namely Interstates 110 and 710, are analyzed to determine if the risk of an accident fell on these highways after the CTP’s implementation. Results, using a negative binomial regression framework, suggest no significant change in accident risk after the CTP implementation.