November 21, 2018
An assumption exists that improvements in bicycle and pedestrian infrastructure will result in decreased carbon dioxide emissions due to decreased driving but not many studies have been conducted to date to confirm this hypothesis, until recently.
A recent study from New Zealand found a 30 percent increase in active travel as a result of bicycle and pedestrian infrastructure improvements. Infrastructure improvements were also found to be linked to a 1 percent reduction in distance traveled by motor vehicle with a commensurate 1.6 percent reduction in carbon dioxide emissions.
The group used odometer readings recorded through New Zealand's licensed vehicle administration system over a three-year period in control and intervention areas to estimate impacts of infrastructure improvements on vehicle miles traveled and emissions. The researchers also conducted in-person household interviews in both groups to determine the socioeconomic characteristics and travel behaviors to estimate impacts on active travel.
Though the reductions in vehicle miles traveled were modest, this study represents one a few attempts to measure the impact of bicycle and pedestrian infrastructure investments on carbon dioxide emissions reduction. It also confirms bicycling and pedestrian improvements encourage communities to engage in healthier behaviors such as biking and walking.