DESCRIPTION
Based on the results of a 5-year post-construction monitoring effort, adaptive management is needed to ensure resiliency of the Stillaguamish estuary and Port Susan Bay Preserve.This project will assess potential actions related to increasing channel and freshwater connectivity across the restoration site and select a preferred alternative for preliminary design sufficient to initiate the permitting process.
The Nature Conservancy’s Port Susan Bay restoration site (PSB) sits along the mainstem of the Stillaguamish River where the river meets the sea. The 150-acresite is critical estuary habitat for fish species such as Chinook, Chum, pink, and Coho salmon as well as Bull trout, Cutthroat trout, and Steelhead. SRFB funds were used to evaluate adaptive management options to enhance ecosystem processes and fish habitat at PSB. Scientific tools including an allometric channel analysis (Hood 2019) and 2D hydrodynamic modeling were used to develop three restoration design alternatives (see Preliminary Design Report, Port Susan Bay Restoration Project, 2020). A preferred alternative was selected that provided a cost- effective method to achieve the project’s goals. Local stakeholders including a Technical Advisory Committee provided important suggestions that helped the team refine the restoration design. A PSAR Capacity grant provided support for additional modeling to ensure that TNC’s restoration design would align with future restoration an adjacent property owned by the Stillaguamish Tribe. A 60% Preliminary Design Report was completed and the permitting process has been initiated.
