An easy to compute index for identifying built environments that support walking

The variety and spatial co-variation of built environment attributes associated with nonautomobile travel have resulted in the estimation of composite scores or indices summarizing these attributes. This paper builds on prior practical and research applications of these environmental scores or indices by proposing and testing a built environment index (BEI) calculated at the traffic analysis zone and that relies predominantly on widely available data. By computing the BEI using three different analytical methods used in prior research (principal components analysis, cluster analysis and a naïve method), we examine whether the indices created are comparable. Results suggest a high correlation between the BEI calculated with these methods, with principal components analysis appearing slightly superior to the two other methods. We also compare the BEI with Portland’s Pedestrian Environment Factor (PEF) and find a high degree of consistency between the two. Because the BEI can be readily calculated, does not rely on field survey data, and has high validity, we recommend it as an overview tool to classify built environments in their ability to support walking. When appropriate, additional disaggregate data can be used to examine the urban neighborhood with higher spatial resolution.