Here’s an interesting tidbit from the ever-geekalicious Todd Litman: a chart comparing average impervious surface per household in urban vs. suburban settings.

 impervious chart 420

As you can see, large single-family lots—the sort of homes that are surrounded by greenery—actually require the most pavement overall, particularly for roads. And while dense cities are typically plastered with concrete, in the final analysis urban high-rises are lightest on the landscape.

This chart was taken from a new “Pavement Busters Guide” (pdf link) with some pretty detailed recommendations for ways to reduce impervious surface in cities and suburbs. Todd’s number one recommendation: Educate Decisionmakers. Sounds like a smart first step to me.