Chapter 6 - Cross Section Elements

6.8. Medians

6.8.2. Arterial (Non-GRIP) Medians

The required medians for arterials (non-GRIP) with posted speeds or design speeds less than or equal to 45 mph are described in Table 6.8.

Table 6.8. Medians for Non-GRIP Arterials with Posted Speeds or Design Speeds < 45 mph
Median	ADT (Base Year)	ADT (Design Year)
5- lane section (flush median)	< 18,000	< 24,000
5-lane section (flush median) (1)	< 18,000	> 24,000
20-ft. raised median (2)	> 18,000	>  24,000
Notes: (1) The project shall be designed to incorporate a future 20-ft. raised median or preferably a 24-ft. raised median depending on impacts. Right-of-way shall be purchased for footprint determined by raised 20-ft. or 24-ft. median typical section. The need and implementation of a raised median section shall be determined by monitoring of accidents and traffic volumes on a five-year cycle by the Safety Engineer in the GDOT Office of Traffic Operations. (2) GDOT prefers the use of a 24-ft. raised median if there are minimal impacts associated with a wider median.

 

Raised medians shall be constructed on multi-lane facilities at intersections that exhibit one of the following characteristics:

• high turning volumes relating to 18,000 ADT (base year) and 24,000 ADT (design year)
• accident rate greater than the state average for its classification
• excessive queue lengths (as determined by District Traffic Engineer) in conjunction with excessive number of driveways

All arterials with design speeds greater than 45 mph will require:

• A 24-ft. raised median with a sloped curb (Type 7 curb-face), which will require a 2-ft. additional paved shoulder offset from the edge of travel to the edge of the gutter (4-ft. inside shoulder width from the edge of travel to the face of the curb).
• A 44-ft. depressed median or a positive barrier system depending upon functional classification, the type of development along the corridor, type of access management and right-of-way impacts.

All multi-lane facilities with three or more lanes in each direction shall include positive separation of opposing traffic using a median. The type of median required shall depend on guidelines stated above.

All rural multi-lane roadways interchanging with an interstate highway shall have a raised median for a minimum distance of 1,000-ft. from the ramp termini or the first major intersection. A median break may be provided in accordance with GDOT’s access guidelines, which are described in this Manual in Chapter 3. Design Controls.