Port Under-Reported Truck Diesel Emissions for Five Years

December 2012 - Consultants for the Port of Seattle recently revised earlier estimates of diesel pollution emitted from heavy duty trucks at the region’s ports. The new emissions modeling reveals that previous estimates greatly under-reported the scale of air-born toxics produced by port trucks and their associated risks for communities located near ports in 2005, putting into question several diesel reduction policies subsequently adopted by the Port due to the under-reporting.

This suggests that hazardous air pollution affecting the nearest port communities may be inadequately addressed by recent Port programs, particularly those aimed at reducing diesel emissions from heavy duty trucks.

Brief Background

In 2007, the Port of Seattle, along with other agencies concerned with maritime-related air pollution, released its first inventory of air pollutants. The inventory assessed the total air pollution footprint for maritime activity around the Puget Sound airshed, including ports.

The inventory included estimates of emissions profiles for each of six active seaports. One purpose was to create an accurate, definitive benchmark to measure progress towards clean air goals.

The initial inventory estimated emissions for 2005. This year, the involved agencies, including the Port of Seattle, released an updated inventory. That inventory models emissions for 2011 and includes a comparison with the results for 2005.

While air emission inventories are critical in understanding overall environmental impacts of maritime operations, such as seaports, they are inadequate to measure the impact such emissions have on public health—particularly to communities closest to the sources. For example, the air emissions from thousands of diesel truck trips in and out of the Port of Seattle primarily affect residents of the Duwamish Valley.

These communities have the most at stake from the total quantity of diesel emissions from created by port trucks. The Duwamish Valley and the Tacoma Tideflats have had some of the highest levels of particulate matter in the region, while the communities living near the Port of Seattle have the highest asthma hospitalization for children under 18 in the entire county. When Puget Sound Sage conducted a community health survey in 2009, 60% of residents of port- adjacent neighborhoods believed port trucking negatively affected their health.

These significant local impacts and related community concerns have been documented through investigative journalism from KCTS and Investigate West in a project called Breathing Uneasy: The air pollution crisis in South Seattle and in media sources as diverse as Seattle Weekly, Crosscut.com, KOMO 4 and the Seattle Times.