depends on the traffic volume, speed, degree of access, and available right-of-way. On
major streets with numerous business drives, a median consisting of an additional
lane, striped as a continuous two-way left turn lane, is appropriate. A solid 6-in-high
(0.15-m) lane concrete median may be used in low-speed areas (where the design
speed is 40 mi/h (64 km/h) or less) and where an all-paved section is desired and a
wider median cannot be justified. Barrier medians are normally recommended for
urban facilities when the design speed is over 40 mi/h (64 km/h). However, care must be
exercised when barrier medians are used on expressways with unsignalized at-grade
intersections because of sight distance limitations and end treatments of the barrier.