Research Roundup — health impacts, Road Diets, & Smart Growth
There are a number of notable new reports out that are worth looking at this week. Here’s a quick summary.
Bicycling health benefits outweigh risks
Dutch researcher Dr. Jeroen de Hartog and his colleagues have published a new study, “Do The Health Benefits Of Cycling Outweigh The Risks?” that concludes that the health benefits of bicycling are “substantially larger than the risks of cycling relative to car driving.” The authors quantify the risks and benefits and determine that the increased physical activity gained from switching from driving to biking lead to “about 9 times more gains in life years than the losses in life years due to increased inhaled air pollution doses and traffic accidents.”
Road Diets decrease crashes
The Federal Highway Administration released a study (PDF) using data from the Highway Safety Information System (HSIS) that shows that reducing four lane roads to three lane roads with center turning lanes and bike lanes in both direction can improve safety without reducing annual average daily traffic (AADT) volumes for roads with under 20,000 AADT. (For more on road diets, here’s the classic Road Diet reference, PDF, by Dan Burden.)
Measuring the impact of mixed use development on traffic generation models
Ken Barfield from the Natural Resources Defense Council (NRDC) has a recent post on the way new models of traffic generation from mixed used development projects are re-shaping zoning requirements. The gist of it is that land-use policies can impact actual traffic generation, but up until now that hasn’t been taken into account in the formulas planners have used. This has resulted in excessive road and parking supply. In response, the Environmental Protection Agency commissioned a study to improve the method by which they estimate the impacts of mixed use designs on traffic.
…the new Safe Routes to School guide (PDF) on implementing the program in low-income schools and communities, and…
… the Alliance for Biking & Walking’s Guide to Complete Streets Campaigns.