Complement or Substitute? An Analysis of Bikeshare’s Effect on Transit Ridership in Portland

Abstract

Free-floating bikeshare is a relatively new service in North America but offers significant mobility benefits and intriguing potential for first- and last-mile access to transit. This study of Portland’s Biketown system will explore whether the introduction of bikeshare has a complementary effect for transit ridership, that is: does presence or usage of bikeshare lead to an increase in transit use? Additionally, because Biketown has both docked and free-floating bikes available, this study will examine whether the introduction of free-floating bikeshare leads to higher increases in transit ridership than traditional docked bikeshare. Because the system has gone through a variety of changes to its home area and operating rules, this study completes a longitudinal study of TriMet transit ridership in areas where service has expanded or docking rules have been changed. This study is unique; although many previous studies have explored the usage of bicycles or bikeshare for first- and last-mile transit access, few studies have considered free-floating bikeshare’s relationship to transit.