The Effects of Commuter Rail on Population Deconcentration and Commuting: A Salt Lake City Case Study

Joanna Ganning, University of Utah


The Wasatch Front is a rapidly growing metropolitan area situated in a region with natural features that extraordinarily limit growth. The Wasatch Front Mountains constrain growth on one side while the Great Salt Lake and the Oquirrh mountains constrain the other. Among the nation’s worst winter inversions occur along the Wasatch Front, whereby high-pressure weather systems trap the air, and all the pollution added by humans, in the valley. The inversions produce red air quality days and significant health consequences for sensitive populations. Furthermore, the water supply issues facing the arid American Southwest encourage conservation and suggest wisdom in promoting density. Part of the region’s efforts to manage growth and natural resources has included a focus on developing a transit system comprised of local and regional bus systems, TRAX (light rail Salt Lake County), the Sugar House Streetcar, and FrontRunner, a commuter rail system connecting urban centers along the Wasatch Front. While research has long suggested that highway infrastructure supply increases infrastructure demand, the effects of a regional commuter rail system like FrontRunner on commuting patterns and urbanization remain under-studied. Accordingly, our central research question is: Does regional commuter rail replace long commutes by car, thus creating a sustainable, integrated urbanized region, or does it facilitate further suburbanization and increase vehicle miles traveled along the route? 

Our study will use census Longitudinal Employment-Household Dynamics (LEHD) data on worker origin and destination from 2002 through 2012, as well as FrontRunner on-board surveys provided from the Utah Transit Authority (UTA). Analysis will combine the descriptive and econometric methods from related literature (Eichler 2011) and previous work done by the PI (e.g., Ganning, Baylis and Lee, 2013; Ganning and McCall 2012). These methods rest on commuting, business, and demographic data sets such as those available from LEHD and the UTA. By addressing the research questions posed below in this proposal, this project addresses two of NITC’s current themes: making the best use of data and analytical tools, and taking long-term action to reduce emissions. While we are hard-pressed to think of a metropolitan area in the U.S. where these objectives are more pressing than the Wasatch Front, we also seek to create generalizable research findings that will enable researchers and practitioners to make sound decisions regarding transit in other regions. 

Project Details

Project Type:
Project Status:
End Date:
January 31,2016
UTC Grant Cycle:
Tier 1 Round 3
UTC Funding:

Other Products

  • How Effective Is Commuter Rail in Spatially Pairing Supply and Demand for Commuting Infrastructure? Salt Lake City Regional Case Study (PRESENTATION)
  • How Effective is Commuter Rail in Spatially Pairing Supply and Demand for Commuting Infrastructure? (PRESENTATION)
  • accepted to Regional Studies (PUBLICATION)