8.1.9 Medians

The ultimate freeway section should be initially designed to reduce the adverse impact to highspeed and high-volume traffic resulting from construction in multiple phases when feasible. Several benefits can be realized from initially constructing the ultimate section such as:
  • Lower levels of traffic handling and traffic shifts;
  • Minimal temporary pavement and interim transitions;
  • Construction and inflation cost savings; and
  • Plans to accommodate future bridge columns and other appurtenances.
Under those circumstances where future additional lanes will be provided in the median area,
the usual median width of 24-ft should be increased by the appropriate multiple of 12-ft in anticipation of a future need for additional lanes.
 Provisions should be made for any future need for managed lanes such as high occupancy vehicle lanes in the median.
On freeways where median barrier is used, the horizontal alignment must be checked for adherence to the stopping sight distance criteria accounting for any restriction caused by the barrier. See
Section 4.10.15
for additional information on median design for freeways.
See
Section 17.9
for additional information on emergency freeway median crossings,