"EPA 231-R-04-001."

Measures the degree of connectivity, the pedestrian environment, and availability of transit in 13 metropolitan areas. Tests the hypothesis that a smart growth transportation system--one that features a relatively dense and well-connected network of streets, shorter block sizes, and extensive transit service--will produce improved transportation and environmental outcomes (reflected by fewer vehicle trips and miles of travel, less congestion, and fewer vehicle emissions) as compared to a conventional transportation system. A conventional system has fewer connections between streets, larger blocks with more circuitous pedestrian routes, and limited transit service.