Urban trails and demand response to weather variations

Engineers and planners need information about factors that affect demand for bicycling and walking to plan and manage transportation infrastructure. This paper presents a set of econometric models that summarize the effects of variation in temperature, precipitation, wind speed, dew point, and hours of daylight on daily bicycle and pedestrian trail traffic volumes. We make three contributions to the literature on non-motorized traffic monitoring. First, we summarize trail traffic monitoring results for 32 monitoring stations on multiuse trails in 13 cities in the United States, including locations across seven climate regions and zones classified by the U.S. Department of Energy. The monitoring results include estimates of average daily bicyclists (ADB) and average daily pedestrians (ADP) for the period, January 1, 2014 through February 16, 2016. Second, we introduce the concept of demand returns by testing the parabola form of the weather factors in the models, and measuring the vertex points of demand functions where use shifts from increasing to decreasing or vice versa in response to linear changes in the weather variable. Third, we compare regional elasticities for each weather variable for both bicyclists and pedestrians. Our results show (1) mean daily trail traffic varies substantially in response to variations in weather, with greater elasticities for temperature than precipitation and other weather variables; (2) the parabola form works well for variables such as temperature, where trail use is associated with warmer temperatures, but only up to a point at which higher temperatures then decrease use; and (3) bicyclists and pedestrians respond differently to variations in weather, and their responses vary both within and across regions. Transportation planners and trail managers can use these results to estimate the effects of weather and climate on trail traffic and to plan and manage facilities more effectively.