Construction work on the I-84 Twin Bridges replacement project near Declo, Idaho, has started with demolition of the westbound bridge.
The $17.88 million project will replace the two 1,100-ft bridges crossing the Snake River in Idaho. The bridges were built in 1960 as part of the interstate’s original construction, but are now considered structurally deficient. Each bridge carries about 7,000 vehicles per day.
The new bridges will be slightly longer, featuring wider shoulders, fewer piers in the water and increased vertical clearance for river traffic.
Work will begin with installation of traffic-control signage, which will cause alternating lane closures and shifts in traffic patterns. Throughout construction, traffic on I-84 will be reduced to one lane in each direction and funneled onto a single bridge.
Access to the westbound on-ramp will be limited as construction work enters its beginning stages.
A temporary traffic pattern will be established in early June and a work platform will be erected between the two bridges.
The westbound bridge is expected to be open to traffic in early 2016. Demolition and construction of the eastbound bridge will follow, with final completion of the project expected in spring 2017.
