This page last reviewed April 24, 2014

In 2011 California’s freight system was responsible for transporting over 165 million tons of goods, valued at over $690 billion, to markets in the United States, and over $180 billion worth of freight exports to markets around the world.  The most extensive and interconnected system in the United States, California's freight system is composed of several deep water seaports, cargo airports, border crossings, and a vast warehousing and distribution sector; all connected by a network of over 11,000 miles of railroad track and Interstate and State highways.  Each component is critical and the system depends on a series of these interconnected facilities working in concert with one another to move freight in and out of California to the rest of the nation and the globe.1


For over a decade, the collective efforts from impacted communities, air quality agencies, the ports, and the freight industry as a whole have made significant progress in reducing air quality impacts from the movement freight.  A major milestone was the adoption of the Emission Reduction Plan for Ports and Goods Movement in California by the Air Resources Board (ABR or Board) in 2006 which identified specific actions to reduce emissions and protect public health.  More recently, regional, State and national efforts, such as SCAG’s 2012 Regional Transportation Plan, California’s Freight Mobility Plan, and the federal reauthorization of MAP-21, have continued to keep freight issues at the forefront of transportation discussions around the State and throughout the country.

In California, the freight discussion includes the recognition that the emissions from ships, harbor craft, trucks, locomotives, cargo equipment, and aircraft continue to be significant contributors of direct PM2.5, black carbon, and greenhouse gas emissions, as well as the nitrogen oxides and sulfur oxides that form ozone and PM2.5.  Most importantly, the interwoven nature of the freight transport system often aggregates the emissions from this equipment in close proximity to nearby residents and poses health risks to surrounding communities; highlighting the need for additional steps to protect public health.

1.  California Department of Transportation. California Freight Mobility Plan (Draft). Available at: Accessed: 3/24/2014.