In March 2013, the Victoria Transport Policy Institute released a new report, “Toward More Comprehensive and Multi-Modal Transportation Evaluation”, which critically evaluates the conventional transportation policy and project evaluation practices and identifies ways in which these processes might be improved.
The author, Todd Litman, suggests that the whole transportation sector is under-going a paradigm shift; from one in which mobility is the goal with automobile travel speed as the major performance indicator; to one in which accessibility (i.e. people’s ability to reach desired services and activities) is the goal with a variety of factors being used as performance indicators which must be balanced.
Conventional transportation planning processes, Litman explains, begin with travel surveys that collect information on travel activity to estimate travel demands. Typically, these surveys under-estimate non-motorized travel because they exclude short trips, off-peak trips, non-work trips, travel by children, and recreational travel. They also tend to ignore the non-motorized links between motorized trips. For example, a transit trip does not indicate if a person cycles, walks or drives a motorized vehicle to the transit stop. Several studies indicate that non-motorized travel is typically three to six times more common than these travel surveys suggest.
According to Litman, conventional evaluation processes use automobile oriented indicators to measure the performance of transport systems such as traffic speeds, congestion delays, and roadway level-of-service. These indicators are used in economic evaluation models to estimate the value of roadway expansions on travel time and vehicle operating cost savings. Missing from these processes are: consideration of alternative modes of transportation such as walking and cycling; and accessibility of services and amenities particularly for those who live on low incomes and those who do not drive because of age or physical or mental ability.
When transportation systems are evaluated for accessibility, Litman reports that the evaluation process considers a broader array of issues such as: traffic network connectivity; land use accessibility (i.e. how close are services and amenities to homes and workplaces); and comfort, safety, affordability and integration of a multi-modal system. A multi-modal evaluation process requires detailed information on travel activity and demands. It needs to reflect the travel patterns of children, the elderly and those who live on low incomes, as well as the average commuter. It needs to include latent demands for alternative modes of transportation such as walking, cycling and transit, and the barriers to these modes of transportation. This evaluation process also requires models that can evaluate accessibility to services and amenities by various modes of transportation and the impact that transportation and land use planning decisions and policies can have on all members of a community.
For more information on multi-modal transportation evaluation systems, see this 20-page report at: http://www.vtpi.org/comp_evaluation.pdf
Prepared by Kim Perrotta, Executive Director (Volunteer), Creating Healthy and Sustainable Environments (CHASE) Kim Perrotta/LinkedIn