Trail Demand Calculator; A Public Utility for Trail Use Estimation

Abstract

Shared-use trails are an important and expansive investment for the well-being of Minnesotans. For our capstone we researched qualities related to trails to develop a trail demand model. This model became the foundation for an interactive trail demand calculator that allows users to estimate trail use. Our model and the TDC was informed by a literature review of trail demand models and key informant interviews. From there we collected data and developed a model that can reasonably estimate trail demand. To create the calculator we summarized trail qualities by census tract or block group and hosted map layers on an ArcGIS web map. We applied our model within a spreadsheet that allows users to input values for trail qualities and are returned with an estimate for trail demand. Our capstone produced two regression models that measure the effects of variables on trail use by estimating the coefficients and created an interactive TDC to populate the models and therefore produce estimates of trail demand. In turn, these coefficients are what forms the basis of our trail demand calculator. The complete model uses 8 variables, which includes demographic variables like population density and median income, geographic qualities like tree cover, slope of the trail, and proximity to water, and activity-based information like density of food and accommodation jobs. The reduced model uses 7 variables, omitting the trail slope variable. We learned from testing the calculator that slope is difficult to approximate without specialized software and knowledge. This raised concerns that results would be skewed by erroneous slope values being input into the calculator. Removal of slope from the regression model resulted in a slight but acceptable decrease in explanatory value for the model. To aid with the mathematics that undergird the calculator and reduce error from inputting data, we created an online-hosted spreadsheet with the coefficients and demand model equations embedded to provide TDC users with an estimated SADT value. The calculator is accompanied by an ArcGIS web map that summarizes and layers the data for each variable. TDC users can reference the web map to collect their inputs for the calculator.