The primary objective of this project is to increase the amount and quality of salt marsh habitats available to juvenile salmon in Admiralty Inlet. In order to achieve this we will evaluate the feasibility and impact of multiple habitat restoration strategies in the western lobe of Deer Lagoon. Restoration strategies will be assessed using hydrodynamic models that will simulate water surface elevations and erosion/deposition. These models provide us with an analytical tool that can be easily communicated to the local community and stakeholders. We plan on using this tool as a major component of our local community and stakeholder outreach effort.

A series of dikes has truncated tidal influence in the western lobe of Deer Lagoon, limiting its value as habitat for juvenile salmon. These dikes have resulted in the loss over 450 acres of potential salt marsh and mudflat habitat in the western lobe of Deer Lagoon. These dikes have also degraded ~100 acres of existing salt marsh on their seaward side, through decreased tidal prism. The reduction of flushing power (sediment transport capacity) from lost tidal prism has decreased the width and depth of the opening of the lagoon, as well as decreasing channel depths throughout the remnant marsh. The depth of tidal channel entrances into salt marsh complexes has been shown to be a key aspect of connectivity for juvenile salmon between these systems and higher energy habitats found outside the marsh. Our project will forecast the physical response of the lagoon system to a variety of restoration strategies. We will work with a qualified consulting firm to develop a hydrodynamic model of the site that will simulate wetting and drying (water surface elevations) and sediment transport. Due to the homes and public infrastructure located adjacent to Deer Lagoon, it will be necessary to model a range of restoration strategies in order to determine how each affects water surface elevations in the remnant and historic areas of the lagoon during storm events. Sediment transport modeling will be used to determine gains in habitat value by examining responses of the lagoon to each restoration strategy. Understanding erosion/deposition patterns in the lagoon will inform our restoration design and will tell us if we need to incorporate anti-erosive measures at the lagoon mouth opening. The results of this modeling effort will be presented to the local community for public input. Wild Fish Conservancy will partner with Island County in a comprehensive public outreach effort for Deer Lagoon, including public meetings and opportunities for input and response from local citizens and landowners with property adjacent to the lagoon. These public meetings will provide a forum for introducing the preferred restoration action at the site and for presenting expected outcomes of all potential restoration actions at the site, including a "no action" alternative.

Deer Lagoon is known to host non-natal populations of juvenile salmon including: chinook, coho, pink, and chum. Fish-use studies conducted by the Wild Fish Conservancy along the western shoreline of Whidbey Island have documented extensive use of nearshore habitats by both wild and hatchery origin juvenile chinook, including CWT recovery from chinook populations tagged in the major rivers of the Whidbey Basin, the Hood Canal, and central Puget Sound.