Score another point for Portland, the king of green cities. SustainLane, a web site devoted to healthy communities, ranked Portland number one in its 2006 list of sustainable cities. SustainLane's second annual study compared the 50 largest U.S. cities in categories such as air quality, public transportation, land use planning, energy policy, and green building. The top 10 winners, in order, are: Portland, San Francisco, Seattle, Philadelphia, Chicago, Oakland, New York, Boston, Denver, and Minneapolis.

SustainLane conducted surveys and interviews with employees of city government agencies and NGOs, as well as compiling publicly available data on scores of issues related to sustainability. The web site provides rankings in 15 categories - and these provide a snapshot of the areas in which each city is excelling or lagging. Denver, for instance, which ranked 9th overall, came in 6th in the "green economy" category, which considers things like number of green buildings and farmers' markets per capita and presence of incubators for clean technology.

Oddly, Phoenix and Albuquerque, two of the cities with the country's worst sprawl problems, ranked in the top 10 in the "planning/land use" category - Phoenix came in 9th and Albuquerque a startling 5th - despite coming in at 22nd and 19th overall. From the web site's explanation of that category, it looks like the main consideration was number of parks per acre or something like that - whereas there are surely better measures of sustainable land use.

Faring worst on SustainLane's city list: Virginia Beach, Oklahoma City, and Columbus.

Photo credit: Sierra Club