This paper describes the innovative breakwater design and construction methodology for a new 400-foot-long breakwater at the Naval Air Station (NAS) Whidbey Island Fuel Pier located on Whidbey Island in Washington State. The breakwater was designed to enable construction within the challenging and highly restrictive existing conditions, environmental requirements, and construction scheduling constraints. The use of precast concrete construction was maximized to enable demolition of existing features and new construction within the permitted 7-month "fish window" from July 15, 2015 to February 14, 2016. Other environmental constraints included the exclusive use of concrete piles, a limited number of piles overall, use of an impact hammer and jetting only for pile installation, avoidance of eel grass areas, and no use of a vibratory hammer for pile extraction or installation. Further, a functional breakwater was required to be in place by the beginning of the storm season on October 15, 2015 in the form of either a permanent installation or temporary shelter. The breakwater comprises precast prestressed concrete vertical and batter piles, precast concrete wave panels, and cast-in-place concrete pile caps. Restrictions on the number of piles required carefully optimizing the design of vertical and batter piles to balance the requirements of wave loads and seismic loads for long slender piles and cohesive soils. This project showcases design innovation and optimization resulting from the partnership between the design-build contractor and designer for an environmentally sensitive site that is home to at least four endangered species: salmon, southern resident killer whales, marbled murrelets (birds), and bull trout.
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