Emissions from the ports around San Francisco Bay contribute to air pollution levels that exceed State and federal air quality standards, leading to unacceptable levels of health risk in the surrounding communities. Diesel particulate matter (DPM) is of particular concern, both because DPM emissions from the ports and port-related activities are regionally significant and because health risk from DPM is a serious concern for the affected local areas. Criteria pollutants of most concern are particulate matter (PM), oxides of nitrogen (NOx), which contribute to ozone and particulate matter pollution, and oxides of sulfur (SOx), which contribute to PM pollution.

To address these pollution concerns, the Bay Area Air Quality Management District assesses emissions and estimates the portion that are associated with the Bay Area ports. Their findings are shown in the table below. According to their estimates, most of the Sulfur Oxide emissions in the region are a result of port activity.

In an effort to reduce the level of emissions from the Bay Area ports, the District is in the process of implementing an action plan that included air quality targets, reducing DPMs, and reducing greenhouse gas emissions overall. The plan identified a set of components aimed at reducing the environmental impact through:

• Establishing a method of quantifying and monitoring emissions levels
• Targeted modification of operations
• Utilize incentives to encourage the adoption of cleaner ship engines
• Policies to reduce energy use of ships at berth
• Increase replacement of inefficient trucks, locomotive engines, and other shore equipment
• Speed reduction policies for vessels
• Implementing container fees to fund the plan commitments
• Setting milestone deadlines for goal achievement and periodic reviews of the plan