Access control may be exercised and established by statute—through zoning ordinances, driveway controls, and turning and parking regulations—and by geometric design. Control by statute is used where full access control or a high degree of access control is required. Direct driveway connections may be prohibited, and at-grade intersections may be allowed only with major crossroads. This may be employed for a major urban arterial.
Zoning can control the type of property development adjacent to the roadway, and thereby influence the amount and type of traffic generated in the area. Property uses can be limited to those that attract very few people, excluding those that would generate significant volumes of traffic during hours of peak movement. Zoning regulations can require off-street parking provisions as a condition for permit approval.
Driveway controls can be effective in preserving the functional character of the roadway. On arterials in built-up urban areas, it is important to establish minimum spacing requirements for driveways, as well as the minimum distance from a driveway to the nearest intersection.
An example of geometric design to control access is the use of a frontage road to provide indirect access of abutting properties to a major arterial. Also, the use of a raised concrete median strip in the center of the road can effectively prohibit left turns into or out of driveways.
