This paper describes new capacity and level-of-service procedures for unsignalized intersections approved by the Transportation Research Board's Committee on Highway Capacity and Quality of Service in January 1997. The new procedures will be published in fall 1997, as part of extensive revisions to the Highway Capacity Manual. The procedures represent significant improvements to those contained in the 1985 HCM and the 1994 HCM Update, with changes for TWSC and AWSC intersections. A new procedure for analyzing roundabouts is also included. (A)
Abstract