Welcome to the worst American drought in half a century. More than half the United States is considered to be in a “moderate or extreme drought.” Missouri alone has recorded 50 wildfires — since June. The corn crop is withering. Yesterday President Obama warned that hot and dry conditions threaten the nation’s food supply. The Secretary of Agriculture reported a third of US counties had been labeled disaster zones.
What does this all have to do with the way we’ve designed our cities and towns? Kaid Benfield at the Natural Resources Defense Council’s Switchboard says our sprawling development patterns are worsening a bad situation:
Now, I’m not naïve enough to claim that the way we have built suburbs and cities over the last several decades is a proximate cause of drought, but sprawling land use can exacerbate some of its impacts, in at least two ways. First, the large-lot residential development characteristic of sprawl uses significantly more water than do neighborhoods built to a more walkable scale, contributing to water shortages. According to EPA research, for example, in Utah 60 percent of residential water use is for watering lawns and landscaping; households on 0.2-acre lots use only half as much water as those on 0.5-acre lots. In Seattle during peak season, households on 0.15-acre lots use 60 percent less water than those on 0.37-acre lots.
The second way in which suburban sprawl exacerbates the impacts of drought is by spreading more pavement around watersheds, sending billions of gallons of rainwater into streams and rivers as polluted runoff, rather than into the soil to replenish groundwater. Again, EPA research is instructive: more compact growth patterns with an average of eight houses per acre reduce runoff per household by 74 percent compared to sprawling patterns of one house per acre. This is primarily because, for a given amount of development, more compact growth requires less runoff-causing pavement for streets, roads and parking lots than does sprawl.
While sprawl may not cause drought, nor smart growth solve it, both need to be considered in the discussion of how to move toward a more resilient future.
Of course, there’s also a third way our carbon-intensive living arrangements are helping to make 50-year droughts more like 10- or 5-year droughts.
Elsewhere on the Network today: World Streets says we need to be more creative and passionate in our appeals for sustainability. Stop and Move notes that ridership is up dramatically three months after the opening of LA’s Expo line, despite some early doomsday predictions from anti-rail spinmeisters. And Walkable Dallas Fort Worth bravely attempts to recap the “worst urban design blunders in DFW.”