Treasure Island Bridge Replacement
Treasure Island Country Club
Mason County, Washington
Treasure Island is a private island on Puget Sound, about three miles south of Allyn in Mason County. This project involved determining the extent of deterioration in the existing, privately owned 789-ft timber and concrete structure; providing recommendations and design for short-term temporary repairs; and project management and civil and structural engineering services for preliminary and final design, environmental permitting, and construction management of a new bridge. The new bridge is 22 ft wide, 787 ft long, with 16 spans of precast prestressed concrete slab superstructure supported on steel pipe pile substructure.
All substructure removal and construction required in-water work. The entire superstructure is over water. Exeltech obtained the building permit from Mason County, as well as the Hydraulic Project Approval, US Coast Guard approval, and USACE permit with NOAA Fisheries consultation. Exeltech also completed a Biological Assessment under Section 7 of the Endangered Species Act.
Exeltech’s services included construction administration, field inspection, documentation, office engineering, environmental management, and water quality monitoring.