Viewshed characteristics of urban pedestrian trails, Indianapolis, Indiana, USA

Abstract

The map accompanying this brief report depicts spatial variation in viewshed characteristics of urban pedestrian trails in the city of Indianapolis, Indiana, USA. Visual openness and visual magnitude were modeled for approximately 50 kilometers of the Indianapolis Greenway Trail System using geographic information system and light detection and ranging (LiDAR) technologies. Viewshed data also were integrated with high resolution satellite imagery to estimate greenness perceived by trail users. The primary map was designed at scale of 1:32,000 and shows visual magnitude overlaid on aerial photography and LiDAR surface height layers. Inset maps illustrate viewshed integration with high resolution satellite imagery to estimate perception of greenness. We have reported statistically significant relationships between pedestrian trail trafic and viewshed characteristics along trail segments as estimated with multivariate regression models that control for other variables, including weather variation, month, day of week, and social and physical attributes of surrounding neighborhoods. In previous studies we also found higher satellite-based estimates of greenness were associated with improved self-reported perception of neighborhood walking environments by children and their families. We note here both current limitations of existing technologies and potential for emerging technologies to improve measurement of pedestrian viewshed characteristics.