Container traffic at the Ports of Los Angeles and Long Beach, California, has tripled in the past 15 years, resulting in massive port-related heavy-duty diesel truck (HDDT) traffic on surface streets in the low-income and minority communities of Wilmington and western Long Beach adjacent to the ports. In response to the limitations of existing data on the volumes of HDDTs on surface streets, this study used direct video measurements of surface street traffic at 11 intersections and line segments in these communities to document port-related truck traffic traveling to and from intermodal facilities, truck service sites, local amenities. and regional goods movement roadways. The volumes of HDDTs often reached 400 to 600/h for several hours immediately upwind of sensitive land uses, such as schools, open-field parks, and residences. Diurnal truck traffic patterns on surface streets varied by intersection, local conditions, and passenger car commute patterns. Given the documented health and environmental consequences of HDDT emissions, the results raise serious public health concerns for the inhabitants who reside, work, attend school, or recreate in close proximity to roadways with HDDT traffic in these communities adjacent to ports. This paper discusses the environmental justice implications of truck-related land use conflicts and current planning and emission control strategies to mitigate the local air pollution impacts of increasing port-related truck traffic in these low-income, minority communities.