Table 2 Intersection Design Guidelines

Table 2 Intersection Design Guidelines

Description Terrain

Terrain Classification
Level Rolling Hilly
Approach Speed (mph) 25 25 20

Clear sight distances1

Approach

200 200 150

At intersection

IAW SSD for intersection Road, but not less than 200 ft.
Vertical Alignment - Maximum grade      

New Roads

3% 3% 4%

Existing Roads

6% 6% 8%

Distance (ft)2

100 100 100
Minimum angle of intersection ** 90 0 +/- 10 0 **
Minimum curb radius (ft)      

Local – Local

25 25 25

Local – Collector

30 30 30

Collector – Collector

35 35 35

Collector – Arterial

40 40 40
Minimum centerline offset from Adjacent intersection3

Local – Local

125 125 125

Local – Collector

150 150 150

Collector – Collector

200 200 200
Minimum tangent length
Approaching intersection (ft)
50 50 50

1 For intersection sight distance calculations, the height of the driver’s eye is considered to be 3.5 feet and located 10 feet from the edge of travel way, and the height of object is 3.5 feet.

2 Measured from the centerline/centerline intersection along both the new side street and the new or existing thru-street.

Residential driveways will be considered as local roads and commercial driveways as collector roads.