Slate Creek Bridge

The new Slate Creek Bridge spans the beautiful and pristine Salmon River in central Idaho. Construction of the bridge started in spring 2010 with the purpose of replacing the older bridge, which no longer met highway safety standards. The project confronted several challenges, including that of not disturbing the river’s pristine waters during construction.

To prevent any turbidity from disturbing the water while the piers were excavated, for example, a special platform was set in the river, rather than driving piles into the riverbed. This allowed for easy removal of debris.

The old bridge was carefully removed after first containing the piers in trench boxes while removing the old slabs with a slab trap. Finally, new girders had to be installed with two specialty cranes weighing 300 and 250 tons.


Idaho Transportation Department


Custer County, ID