Freight Activity and Air Quality Impacts in Selected North American Free Trade Agreement Trade Corridors

The current and future air quality effects that result from the development of North American trade and transportation corridors are examined, and strategies to mitigate these impacts are explored. The analysis focuses on five specific binational corridor segments. For each segment, commodity flow and ground freight traffic volumes (truck and rail) are used to develop a sketch-level estimate of current air pollution emissions associated with cross-border trade. Cross-border freight is responsible for 3% to 11% of all emissions of nitrogen oxides and 5% to 16% of all emissions of particulate matter smaller than 10 μm (PM₁₀) from mobile sources in the corridor regions. Trade forecasts to 2020 are used to develop a sketch-level estimate of future trade-related emissions. Carbon dioxide emissions from cross-border trade will increase 2.4 to 4 times over current levels in the five corridors. As a result of the expected improvement in criteria pollutant emissions controls for trucks and locomotives, total trade-related emissions of nitrogen oxides and PM₁₀ in 2020 will be lower than or the same as current levels, despite increased trade volumes. The effects of six emissions mitigation strategies are also discussed.