The Cost of Shade: Cost-Effectiveness of Trees Versus Bus Shelters

Abstract

Shade at bus stops can enhance the thermal comfort of waiting riders and can encourage new passengers, thereby reducing air pollution and traffic congestion. This study used computer simulation to compare the cost-effectiveness of shade provided by metal shelters versus trees at 64 bus stops in Tucson, Arizona. The 40-year projected total future and present values of costs were over 50% greater for shelters than for trees. When differences in the amount of shade provided over time were considered, a 20% cost savings was projected for trees. Expenses for irrigation and pruning accounted for about 95% of all projected tree costs. These findings suggest that trees can be a cost-effective substitute for shelters at bus stops in mid-latitude cities where shade is useful.