Abstract
The Long Beach Freeway Corridor Improvement Project was started to address concerns regarding increasing air pollutant emissions and traffic congestion, which are partly due to increases in truck volumes and high accident rates. In addition to these efforts, a non-profit organization called PierPass was created in 2005 by the marine terminal operators at the ports of Los Angeles and Long Beach. The PierPass program aimed to alleviate congestion, security and air quality issues experienced by the ports and freeways by incentivizing freight movements during off-peak hours. This paper explores whether it is important to model accidents when analyzing the environmental benefits of policies designed to reduce air pollution from trucks with an application to PierPass. A microscopic traffic simulation model of the freeway network containing the I-710 freeway was utilized to simulate truck accidents under uniquely identified scenarios based on frequent conditions. Then, vehicular emissions for seven common air pollutants were calculated and compared to a no-accident scenario to quantify the effects of accidents on pollutant emission. Results showed that the introduction of incidents slightly increased the average vehicular speeds and slightly decreased the total amount of emissions; however, the effect of incidents may be more pronounced on a network that is not already known to be heavily congested.