Issues Relating to the Geometric Design of Intersections

This paper presents five issues, or topics, that the author suggests be addressed in the design of intersections. These are: 1) turn trajectory of vehicles; 2) the radii connecting the curb, or edge of pavement, of the two intersecting roadways; 3) intersection area; 4) the inclusion of deceleration/turn lanes; and 5) visibility of the intersection to approaching drivers. It is also to be noted that a driveway serving private development is an intersection. Therefore, the intersection of a private driveway with a public roadway should be treated the same as the intersection of two public roadways. Moreover, the intersection of two on-site circulation roadways should be given similar attention [2004 ‘Greenbook’, p. 729].