Section 5: Driveway AngleAnchor: #i1067459
Two-way driveways should intersect the roadway at an angle of ninety degrees unless it is determined that a lesser angle will provide satisfactory traffic operations for the highway. Just as it undesirable for two roadways to intersect at highly skewed angles, it is undesirable for most driveways to intersect the roadway at a large skew. When a skew angle forces drivers to deal with a turning angle that is much less than or greater than 90 degrees, drivers will have greater difficulty turning their heads to scan the through roadway for an adequate gap, and more distance and time is required to complete an acute angle turning movement. Research has shown that the intersection angle of driveways should not be skewed from 90 degrees by more than 15 to 20 degrees. Suggested limiting values of two-way driveway angles are:
- Anchor: #FXWWTVUU
- Private Residential Driveway: 75 degrees; Anchor: #UMTFUCPA
- Commercial Driveway: 75 degrees; A commercial driveways expected to have a volume of 400 vehicles per day or two or more trucks/large vehicles in a one-hour period must be designed as a public driveway; Anchor: #KPDHPDTB
- Public Driveway, Service Driveway and Field Driveway: 80 degrees.
The angle of intersection between the centerline of a one-way driveway and the edge of pavement of the public roadway may be between 45 and 90 degrees. Engineering judgement should be used when selecting an intersection angle for one-way driveways based on field conditions and sight distance viewing angles (i.e., right-turn entry-only, right-turn exit-only, left and right-turn entry-only, or left and right-turn exit-only).