12. Milwaukee, WI

Since Milwaukee inaugurated its first office of sustainability in 2006, green momentum in the Midwestern city has picked up steam. Located on the western shore of Lake Michigan, Milwaukee has invested in New Urbanist redevelopment, consciously folding sustainability into it’s planning and design (one green public housing development nabbed a Sierra Club honor in 2005). It has also taken great care to manage storm water and reduce runoff into the lake and area rivers. And that’s not all: In 2006, five percent of its fleet vehicles ran on alternative energy. A year later, more than 40 percent of the city's fleet are powered by alternative fuel. A 2006 energy audit of the City Hall complex led to power-saving measures that reduced energy use there by nine percent and saved the city $35,000 in one year. The city also has public outreach campaigns for recycling, composting, and water conservation. The city’s updated bike plan may help get the near-75 percent of car commuters heading out to work…riding their bikes instead!