The Boston Street Bridge (Lower Custer-Way Bridge) over the Deschutes River is the only non-railroad or trail bridge in Thurston County over 100 years old.
A strong multimodal network relies on safe and functional bridges for all modes. The Federal Highway Administration requires all public bridge owners to inspect and report on bridge condition once every two years. 97% of Thurston County bridges are in fair or better condition.
Of the local bridges, four are in poor condition, including three on the Chehalis Western Trail (former railroad bridges) and one over Percival Creek.
The 93rd Avenue Bridge over I-5 in Tumwater was struck by an over-height load in 2015 and underwent repairs in 2017. Such low I-5 overpasses are considered functionally obsolete