Power > Projects >

Longmire Suspension Bridge Repair

LOCATION:

Longmire, WA

DESCRIPTION :

The Longmire Wooden Truss Suspension Bridge is one of the longest timber suspension bridges for vehicles in the US. Despite its heavy structure, it still moves as you cross it. Built in 1928, this historic bridge needed to be restored in kind to the original specification, using as much local material as possible. Power Engineering Construction replaced the main timber span structure and deck to ensure its continued use as a key entry point to the Longmire portion of Mt. Rainier National Park. The replacement of this remote timber bridge posed numerous concerns as the structure was located in an environmentally sensitive location high above the Nisqually River. The repair called for the use of as much of the existing structure as possible to reduce the impact of the project in this pristine setting and to maintain the historic character of the bridge. The bridge restoration called for shoring the span sequentially, removal and demolition of the old timber framing, installation of new timber trusses, beams, and deck, and reconstruction of the support towers. Power Engineering used equipment large enough to handle the replacement timber, yet light enough to traverse a partially demolished structure. Care was taken to remove only enough timber support to allow work to proceed without compromising the integrity of the overall structure. Safety while working at elevation was paramount, making pre-construction engineering, job planning, and preparation paramount. All demolition was completed using non-sparking tools and no open flame was allowed. This project was completed on time with high marks from the National Park Service.