The San Pedro Bay Ports (SPBP) of Los Angeles and Long Beach in Southern California is one of the largest port container complexes in the world, and the largest one is the United States. To decrease the air pollution associated with port operations, a number of measures have been adopted, including the Clean Trucks Program, which was introduced in 2008 to clean up the fleet of drayage trucks serving the SPBP. The objective of this paper is to quantify the reduction in emissions attributable to the Clean Trucks Program, with a focus on Nitrogen Oxide (NOx) and Particulate Matter (PM2.5). Our approach is innovative as it relies on micro-simulation to capture the link between congestion and pollutant emissions. We find that the Clean Trucks Program could contribute significantly to the emissions of NOx (~27%) and PM2.5 (~25%) for all the freeway traffic in our study area. These preliminary results suggest that the Clean Trucks Program is promising, but its cost-effectiveness should be analyzed.

Escalating concerns about air quality in Southern California have led authorities of the Ports of Los Angeles and Long Beach, also known as the San Pedro Bay Ports (SPBP), to consider and adopt a number of emission mitigation measures. One possibility is to shift to trains some of the containers currently transported by drayage trucks. This alternative is attractive because it would decrease congestion and air pollution on the main freeways (I-710 and I-110) and arterials that serve the SPBP. In addition, it would increase road safety along the busy Alameda freight corridor between the SBBP and downtown Los Angeles. One drawback would be an increase in pollutant emissions from train operations in the Alameda corridor, but trains tend to pollute less than trucks per ton-mile and new federal regulations are tightening the emission standards for diesel locomotives. The goal of this paper is to quantify the net impact of such a modal shift on the emissions of PM and NOx, which are the two air pollutants of most concern in the SPBP area. Our analysis relies on microscopic simulation to better capture emissions resulting from stop-and-go traffic on the freeways serving the SPBP. We find that emissions of both NOX and PM2.5 can be significantly reduced by switching from drayage trucks to trains. This suggests that modal shift should be encouraged, especially if there is unused 16 train capacity, and as long as it does not conflict with the shippers’ interests.

The San Pedro Bay Ports (SPBP) complex of Los Angeles and Long Beach is the largest container port in the U.S., and a very important contributor to both California’s and the nation’s economies. Although the benefits of the SPBP activities are enjoyed by the whole country, the burden of the congestion and air pollution it generates falls mostly on the shoulders of people who live and work in the transportation corridor serving the SPBP. This corridor includes two busy freeways, the I-710 and the I-110, and a busy rail link, the Alameda corridor. The objective of this paper is to explore an integrated approach for evaluating the environmental and health impacts of freight operations between the SPBP complex and downtown Los Angeles, some 22 miles north. Our integrated approach combines a number of models, including a microscopic traffic simulation model and an emissions model to better estimate the impacts of congestion on air pollution, emission estimates from line-haul and switching train activities, a spatial dispersion model, and a health impact model. We analyze emissions for year 2005, which serves as a baseline in various air pollution inventories of the SPBP complex. Our results show that emissions concentrations are strongly affected by meteorological conditions and seasonal variations (winter is worse than summer); moreover, we found that health impacts from NOx and PM exposure exceed 200 million dollars, which justifies a number of regional initiatives to improve air quality. Our analysis is a starting point for analyzing the economic efficiency of these initiatives, which include modal shift (from trucks to trains) and the Clean Trucks Program.

The San Pedro Bay Port (SPBP) of Los Angeles and Long Beach is the largest container port in the U.S. Although the benefits of handling and hauling freight are enjoyed by the nation as a whole, the traffic congestion and air pollution created by the port falls mostly on the people who live and work nearby and along connecting freight corridors. These corridors include two busy freeways, the I-710 and the I-110, and an active rail link, the Alameda corridor. 

This research studied the environmental and health impacts of freight operations between the SPBP and downtown Los Angeles, some 22 miles to the north. In our analysis of health impacts, we focused on nitrogen oxide (NOX), a contributor to the formation of photo-chemical smog, and fine-grain particulates (PM10), which can lodge in peoples’ lungs with repeated exposure. We combined estimates of air pollutants from the I-710 and I-110 freeways, line-haul rail lines, and rail yards and looked at them for summer and winter. Four models were linked together to assess impacts: a microscopic traffic simulation model (TransModeler), which describes vehicle behavior; an emissions model (EMFAC 2007), which estimates the impacts of congestion on air pollution; a pollutant dispersion model (CALPUFF), which calculates how emissions move in a region’s atmosphere; and a health impact model (BenMAP), which calculates various pollutants’ effects on health using the incidence of various pollution-related illnesses.

A number of strategies could reduce emissions along active freight corridors like the SPBP. These include: intelligent transportation systems (ITS), advanced traffic operations and control measures, shifting freight from trucks to trains, and increased use of clean-diesel trucks. The health impacts of such strategies should be closely studied in coming years. Our analysis is being expanded to measure health impacts of trucks not only on freeways that feed directly into the port, but also on nearby local streets and other freeways in the corridor.