The Challenge: When planners and policy-makers look to make new investments in the transportation system, they turn to travel demand models to see what the effects of those investments will be. Because of the wealth of research backing them up, these models do well at predicting how automobile drivers will respond to a new freeway or arterial lane. Those same models, however, have either ignored bicycle trips altogether or treated them simplistically.
Make an impact: A policy-maker seeking to increase active trips has little idea which investment would accomplish that goal, putting bicycle projects at a disadvantage. Information on cyclists' actual routes are needed to determine which routes they prefer and why.
What the findings are about: This brief discusses findings from research in Portland, OR on cyclists related to route choices - determining the attractiveness of paths, bike boulevards and the effect of intersection design, turns and slope. The brief also explains how the research has been incorporated into the regional travel demand model that helps inform regional and local transportation investments.
Key Findings and Recommendations:
Cyclists will go 26 percent out of their way to use a separated path, 18 percent to use a bike boulevard.
Cyclists will detour 16 percent of their trip to avoid a left turn at a busy intersection with no traffic light.
Each additional turn is equal to adding 7 percent of the trip distance.
Metro, the Portland area’s metropolitan planning organization has incorporated the findings into its regional travel demand model. Now, when local governments want to study the impact of a bike trail along a suburban light-rail line, to use one recent example, or to compare a host of improvements to a state highway corridor, to use another, they can run the model to find the most effective way to meet their goals.
Oregon Transportation Research and Education Consortium. Clearing a Path for Bicycling Investments. Portland, OR: Oregon Transportation Research and Education Consortium, 2012. Available from: http://otrec.us.