From the Golden Gate Bridge to the Big Apple, many of America's major cities are being recognized as trailblazers in the push to go green.
"Cities that rank high in any sustainability rating due so because they have a planned systematic approach that has a sharp focus on setting goals and creating projects that meet those goals," says Richard Kassel, a senior attorney at the Natural Resources Defense Council.
Last year, Kassel served on a six-member panel of experts that helped Siemens and the Economic Intelligence Unit rank the greenest cities in the United States and Canada. The survey assessed the environmental performance of 27 major cities across nine categories: greenhouse gas emissions, energy, land use, buildings, transportation, water, waste, air, and environmental governance.
"Ranking cities is always an exercise in comparing apples and oranges because every city has unique characteristics," says Kassel. "What matters is that you end up with a list that separates cities that are trying to do something in a data-driven, quantitative, comprehensive way from those that are not."
We've highlighted the top 5 green cities:
1. San Francisco, California
Strongest category: Waste
The fourth most populous city in California has a long history of environmental activism. The Sierra Club, one of the largest environmental organizations in the U.S., was founded in San Francisco in the 19th century. Today, the Golden Gate city continues to be a green leader, in part because of its strong waste reduction policies. In 2007, San Francisco became the first metropolis in the country to ban plastic bags from all the city's grocery stores and pharmacies. The city also manages to divert 77 percent of recyclable material from the landfill — the highest in the country.
2. New York, New York
Strongest category: Land use
Despite being home to more than 8 million people (27,700 people per square mile), New York City is recognized as a leader in land use as it continuously seeks out opportunities to create more green space. In 2007, the City launched an ambitious campaign to plant one million trees across the five boroughs over the next decade. So far, MillionTreesNYC has planted more than 500,000 street and park trees. New York City is also lauded for having the highest share of workers commuting by public transport, bicycle or foot.
3. Seattle, Washington
Strongest category: Buildings
Twelve years ago, Seattle became the nation's first city to mandate that all municipal buildings over 5,000 square feet achieve a LEED silver certification. Today, the coastal city has one of the highest concentrations of green buildings in America. In 2011, thanks to a $20 million grant from the U.S. Department of Energy, Seattle announced its plan to retrofit more than 2,000 buildings with energy-efficient technology. The goal is to cut energy costs by up to 45 percent and reduce carbon emissions by 70,000 metric tons by June 2013. In February, 125 homes had completed energy upgrades or had upgrades in progress.
4. Denver, Colorado
Strongest category: Environmental governance
Colorado's capital is one of the few cities to provide subsidies or tax breaks for the use of green energy in homes and businesses. Citywide environmental programs are driven by the Greenprint Denver Office, which has executed several major energy-saving initiatives since its inception in 2007. In 2010, sustainable achievements included the installation of 2,000 LED bulbs in 200 traffic signals and adding four megawatts of solar PV cells to city and public school buildings. Denver residents are also encouraged to participate in Green Teams, community volunteers that go door-to-door offering energy-efficiency services such as free curbside recycling registration and free compact fluorescent light bulbs.
5. Boston, Massachusetts
Strongest category: Water and Energy
Over the last decade, an aggressive water conservation program led by the Massachusetts Water Resources Authority has helped Boston achieve its goal of keeping total water consumption below 300 million gallons per day. The city is also involved in a statewide goal to retrofit buildings with low-flow toilets. Since 2008, Boston has given grants to replace about 1,000 toilets and conduct water audits.
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