9/28/2015
Reed Hollinshead
ITD Communication
208-334-8881
reed.hollinshead@itd.idaho.gov
Lewiston's Spalding Bridge repair wins national award for environmental efforts
LEWISTON - The Spalding Bridge repair project in Lewiston was presented with an American Association of State Highway and Transportation Officials (AASHTO) President's Award for environmental stewardship yesterday (Sunday, Sept. 27) at AASHTO’s annual meeting in Chicago.
This marked the fifth AASHTO President’s Award the Idaho Transportation Department has won in the past six years. The AASHTO President's Award is considered one of the highest honors that can be given to a state transportation department.
ITD’s Spalding Bridge Project, completed in early fall 2014, saved a critical 1,200-foot bridge over the pristine Clearwater River, while also enhancing habitat for threatened fish species such as bull trout, Snake River Basin steelhead, and Snake River fall Chinook salmon, in addition to other rare species such as Westslope Cutthroat trout.
Click here for a picture of the bridge.
The
Clearwater River is one of the most scenic rivers in the United States.
It contains robust populations of fish and wildlife, and provides a
rich history. The Middle Fork of the Clearwater River was one of the
first rivers designated under the U.S. Wild and Scenic Rivers Act.
Anglers and paddlers from all over the world travel to experience the
Clearwater’s thriving fisheries, thrilling whitewater and spectacular
scenery.
The project involved a fast-moving body of deep water
that runs at an average 15,300 cubic feet per second, requiring ITD to
develop innovative mat-placement techniques. The water moves too fast
for divers, so ITD developed unique solutions involving GoPro cameras,
time-lapse photos, and aerial monitoring from a drone to ensure proper
placement of A-JACKS mats. A-JACKS is an articulated riprap technology
that provides armoring protection for bridge foundations and piers.
Crews
placed nearly 400 concrete A-JACKS mats, weighing 2,700 pounds each, on
the riverbed to provide armor against erosion. The voids in the mats
provided a support system for the river gravel and improved fish
habitat.
Click here for a picture of the A-JACKS mats underwater, and crews setting the mats near the bridge pier.
The
bridge, built in 1962, was rated among the top 10 most scour-critical
bridges in the state — at risk of failure due to erosion. The A-JACKS
technology helped ITD complete the project ahead of schedule and under
budget. Because of heavy river flows, had this project not been done, the
bridge could have failed, resulting in injury, loss of life, and
destruction of critical habitat for bull trout, Chinook salmon, and
steelhead—all threatened species. This technology provided substantial
environmental benefits to the marine life and to the Nez Perce Tribe,
who rely on the fish for sustenance.
ITD coordinated with the
Nez Perce Tribe’s employment rights office and the Idaho Department of
Fish and Game, and obtained permits from the Environmental Protection
Agency (particularly the 401 permit). One-half of the crew working on
the project were Nez Perce Tribal members.