13 during peak hours, congestion cost savings can average 10 to 35 cents per vehicle-mile traveled in urban areas during peak times (Litman, 2011). Another study estimates that shifting from driving to bicycling for 160 annual trips of average length can reduce congestion costs to other road users by approximately 28 cents per kilometer in urban areas and 14 cents in rural areas (SQW Consulting for Cycling for England, 2008). Environment The transportation sector accounts for nearly 28 percent of greenhouse gas emissions in the United States (Bureau of Transportation Statistics) and nearly 50 percent in Washington state (Washington State Department of Transportation, 2009). Shifting trips from driving in single-occupant vehicles to bicycling and walking reduces the use of fossil fuels and per capita air pollutants and greenhouse gas emissions. An Atlanta-based study, for example, found that for each one-point increase on a five-point walkability scale in communities, levels of nitrous oxides and volatile organic compounds (ozone) decreased 6 percent and 3.7 percent, respectively. Researchers also found that residents in the least walkable neighborhoods generated about 20 percent more CO2 emissions than those living in the most walkable areas (Frank). Other studies have demonstrated the costs associated with motor vehicle use by quantifying motor vehicle pollution. For instance, automobile, air, noise and water pollution are estimated to cost the society between two and 15 cents per vehicle-mile (lower in rural areas and higher in urban areas). Todd Litman of the Victoria Transportation Policy Institute (VTPI) suggests a reasonable estimate for the monetary environmental savings of shifting from driving to non-motorized modes is 10 cents per mile for urban, peak-hour driving, five cents for urban off-peak driving and one cent for rural driving (Litman, 2011). Equity and Mobility Benefits Improving bicycling and walking infrastructure can offer significant mobility and equity benefits to people who are unable or choose not to drive. In the quantifying
United States, more than 60 million people are below the driving age, and another 30 million do not drive for other reasons, such as old age, disability, choice and economics. In a typical community, between 20 and 40 percent of residents do not drive. In King County, Washington, around 9 percent of all households do not own a vehicle – approximately 74,000 households (Place, 2011). Moreover, the demographics across the country and within King County are shifting – the proportion of King County residents who are 65 and over is projected to nearly double by 2050 and approximately 22 percent of older adults do not have access to a vehicle or don’t drive. There are different approaches to monetizing the mobility and equity benefits of non-motorized transportation improvements. Litman suggests calculating mobility benefits based on transit subsidies, which provide a estimate of society’s willingness-to-pay to provide mobility for non-drivers. These subsidies average about 60 cents per transit passenger-mile, 30 cents of which is intended to address basic mobility needs for non-drivers (Litman, 2011). Real Estate Benefits Several studies have shown the relationship between property values and proximity to bicycle and pedestrian amenities. Based on both primary and secondary data analysis, the NCHRP 552 research found that an urbanarea home 400 meters closer to an off-street bicycle facility resulted in a net benefit of $510 (Transportation Research Board, 2006). Another study evaluating home values in relationship to WalkScore numbers concluded that for every one point increase in the WalkScore value, there was an associated $500 to $3,000 increase in home value (Cortright, 2009). In San Diego, a report released by WalkSanDiego revealed that neighborhoods characterized as more walkable maintained almost 5 percent more of their property value than those in unwalkable neighborhoods. Studies have also shown walkability and proximity to trails to be a primary factor in homebuyer preference (Litman, 2011). Results from a 2002 National Association of Home Builders and National Association of Realtors survey found that 27 percent of respondents wished they could walk to more
& prioritizing non-motorized transportation investments