Little Falls, Gorham: Reconstruction to a Modern Roundabout

Abstract

Older American traffic circles can typically handle high traffic volumes, but they often have poor safety records. Modern roundabouts are similar to traffic circles in the sense that traffic “circles” around a central island, but many other design concepts differ. The first modern roundabout in Maine was opened to traffic in July 1997. The total accident rate after 16 months of operation is below that which would be expected if the junction had been signalized. There still has not been a single accident with injuries, and the injury rate is expected to stay significantly below that of a signalized intersection. The one-lane design will be able to handle traffic growth for years to come. Vehicle exhaust has been reduced, and delay on the minor approaches has been reduced by approximately 80 percent during morning and afternoon peak hours. In total, the reconstruction will save 5,000 to 10,000 h of travel time annually. This alone will pay for the investment within 5 years.