Watershed benefits of smart growth duplicate transportation benefits, according to recent research

Kaid Benfield’s Blog

Research findings published last year in the Journal of the American Water Resources Association confirm earlier studies by the federal Environmental Protection Agency showing that, for a given increment of development, compact neighborhoods built to a walkable scale reduce stormwater runoff volume.

The article, written by John Jacobs, director of the Texas Coastal Watershed Program and Ricardo Lopez, a faculty member at Baylor College of Medicine, quantifies the per-capita impacts of different residential densities on watersheds, finding that the benefits of relative density (compared to sprawl patterns) begin at around 8 units per acre, increase substantially up to around 32 units per acre, and then continue but at a diminishing rate of increase after 64 units per acre: