Air Quality

How We Rated Cities on Air Quality

To calculate air quality for each of the cities, we crunched EPA data on average Air Quality Indexes along with EPA data on Clean Air Act Non-Attainment areas.

This is one category that honors the old adage, “Location, location, location!” Honolulu once again nabbed the top spot in this category. The Pacific island city owes its clean air to ocean breezes that blow pollution out to sea. Fresno, California can thank its less-than-lucky coordinates for its finish too: With a high concentration of agricultural operations, dairy farms, busy Interstates (5 and 99), and being stuck downwind from Los Angeles, the inland valley city finished dead last.

Clean Air Act

Virginia Beach, Louisville, Indianapolis, Chicago and Los Angeles/Long Beach all enjoyed fewer Clean Air Act violations in 2007, improving their scores since we last took a tally. Although Los Angeles bettered its 2006 marks, it did not rise in our air quality rankings when compared to other US cities.

Two cities where air quality went south included El Paso and Las Vegas; both cities had more non-attainment violations of the Clean Air Act than in our last survey. Their lower scores can probably be attributed to rapid population growth, increased traffic, and warmer weather.

2006 vs 2008

Overall, 19 cities improved their rankings relative to other cities. Six cities stayed in place, and the remainder dropped. Across the 50 cities we studied, air quality dropped slightly between 2006 and 2007.

Milwaukee and Columbus garnered the highest increases in air quality rankings, jumping 17 places each. On the other end of the spectrum San Diego dropped the most, also by 17 places. The winter of 2007 was warmer than average, which may account for better winter air quality across the northeast. This was true both in the beginning and end of 2007.

New Orleans' air quality improved significantly. In the wake of Hurricanes Katrina and Rita, the city government replaced 100 percent of its (flood damaged) fleet with alternative fueled vehicles, which may account for some of the improvement. Hurrah. The dramatic decrease in population—thousands of residents never moved back—would also mean there was less overall combustion of fossil fuels.

Creating Cleaner Air

So how does one improve air quality? There are very practical steps that cities, and individuals, can take:

Add/upgrade infrastructure for walking and bicycling (more sidewalks, bike lanes and trails; working bike racks; pedestrian signs in addition to street signs for car drivers; benches, drinking fountains and parks)
Increase the density and diversity of downtown buildings; if your city/suburb has no “downtown”, create one.
Add light rail and/or street trolleys to service the areas where people currently only have driving options. (Great examples are Charlotte (which has done so), Phoenix (where it’s under development) and Detroit(!) which recently announced its intentions.)
Ask your city to green up its fleet: purchase only hybrids and alternative fueled vehicles going forward, cut down overall fleet size, add car sharing services and bicycles
Demand that your public or private electric utility add more renewable energy sources to their mix, reducing reliance on dirty coal-fired power plants or increasingly expensive, though somewhat cleaner, oil- and natural gas-fired power plants.
Ask not what your utility can do for you, but what you can do your utility (bill): insulate your own home or business to reduce the need for costly heating/air conditioning in the first place
Ask your city and neighbors and friends to plant more trees: they’re nature’s technology! Not only do they look beautiful, but also filter air (and water), raise property values, provide fruit, and keep us all cooler during hot summers.

More aggressive cities, such as San Francisco, New York and Milwaukee, have removed miles of freeways from their downtowns entirely.

Resources:

Sustainlane