42. Long Beach, CA

Together with Los Angeles, the port of Long Beach bears the eco-brunt of US trade. The two comprise the largest port system in the United States; goods that enter the US here are put on trains and trucks and transported across the country. It’s a recipe for eco-disaster: take idling ships (each of which can produce as much air pollution as 12,000 cars), add a major airport, throw in some of the most congested roads and freeways in the country, and you've got a near-last place finish in SustainLane's 2008 air quality category. In recent years though, officials have been working to green port operations. The city instituted a voluntary Green Flag program, where ships voluntarily slow down as they near the port, reducing their emissions. The Port of Long Beach is also leading a global "cold ironing" trend; ships plug into generators while at the dock rather than idle. Outside of the port, Long Beach established a formal Office of Sustainability in 2008. Coordinators are drawing up a comprehensive plan for sustainability, which is expected to include green building mandates and incentives as well as a call for a greenhouse gas inventory.