Table 6.9. Medians for GRIP Corridors (Rural Arterials)

Median

ADT
(Base Year)

ADT

(Design Year)

Design Speeds < 45 mph

5- lane section (flush median)

< 18,000

< 24,000

20-ft. raised median (1)

> 18,000

> 24,000

Design Speeds > 45 mph

44-ft. depressed median

n/a

n/a

Note:(1) If there are minimal impacts associated with a wider median, the use of a 24-ft. raised median is preferred.