BOISE
-- Traffic impacts for Idaho 21 drivers east of Boise are expected to begin
Monday (July 19) on a project to improve safety for motorists and wildlife. ITD
believes construction of a wildlife underpass will help reduce the number of
large game/vehicle collisions along the scenic byway.
Idaho 21 will be reduced to a single, signalized detour lane starting at 8 a.m.
at approximately milepost 18.2, about a half-mile north of the Mores Creek
Bridge. Before the underpass is constructed, crews must build a paved diversion
road for traffic to move through the narrow two-lane corridor.
Drivers are cautioned to watch for trucks entering and exiting the highway. The
speed limit is reduced to 35 mph in that area. Traffic signals at either end of the
project will control the 650-foot, single-lane detour around the work zone. The
lane detour will stay in effect until early October while crews excavate the
existing roadway and construct a new 75-foot bridge to allow wild game animals
to cross under the highway.
The location of the underpass was selected because of its historic road-kill
numbers and known migratory routes.
Each year there are 75-100 vehicle collisions with mule deer and 5-10
collisions with elk, costing the state an estimated $750,000 to $1 million in
insurance claims, deductibles, medical expenses, disability leave, lost
wildlife resources, and manpower and equipment for carcass removal.
McAlvain Construction is the contractor. The cost of constructing the underpass
and surrounding fences is $756,000. Work should be completed by early
fall.
ITD reminds drivers to slow down in the work zone, watch out for construction trucks moving in and out of the roadway, and pay close attention to traffic signs and signals. Motorists also are encouraged to plan ahead and dial 5-1-1 or visit 511.idaho.gov for information on the state highway or interstate system.