Middle States Geographer, 2006, 39:26-33 LOOKING FOR THE RELATIONSHIP BETWEEN SPRAWL AND WATER QUALITY: A CASE STUDY OF GLOUCESTER COUNTY, NJ

ABSTRACT: It has been argued that sprawl (low density, dispersed and land-consumptive development) imposes greater consequences to the environment than Smart Growth development (compact, mixed-use, pedestrian friendly, etc). This analysis explores the relationship of sprawl/smart growth to one very widely used indicator of water quality, impervious surface. The research utilizes Gloucester County as a case study. The study first grades residential development in the county for the degree of sprawl utilizing a housing-unit population density sprawl metric. The analysis then evaluates impervious surface at the basin, watershed, and sub-watershed level. A correlation evaluation is then made between the residential density, population, and percentage amounts of impervious surface within each watershed extent. The results indicate that while sprawl development actually has less intense impervious surface coverage per acre due to its dispersed nature, the total impervious surface contributed by sprawl is substantially higher than contributed by smart growth when calculated on a per-capita basis. The study supports the contention that Smart Growth is locally more impacting to water quality at the site-level due to its compact nature but overall less impacting on the regional-level due to its smaller total footprint compared to low-density sprawling patterns of development