Decreasing vehicle travel lanes for pedestrians to cross,
Providing room for a pedestrian crossing island,
Improving safety for bicyclists when bike lanes are added,
Providing the opportunity for on-street parking,
Reducing rear-end and sideswipe crashes, and
Improving speed limit compliance and decreasing crash severity when crashes do occur.
"Roadways with Average Daily Traffic (ADT) of 20,000 or less may be good candidates for a road diet and should be evaluated for feasibility. It has been shown that roads with 15,000 ADT or less had very good results in the areas of safety, operations, and livability."
"Driveway density, transit routes, the number and design of intersections along the corridor, as well as operational characteristics are some considerations to be evaluated before deciding to implement a road diet. Road diets can be low cost if planned in conjunction with reconstruction or simple overlay projects, since a road diet mostly consists of restriping."
from CenterLines, the e-newsletter of the National Center for Bicycling & Walking.