Marine Shoreline Design Guidelines - New Aquatic Habitat Guidelines Performance Assessment and Guidance Document for “Soft” and “Hard” Shore Protection Techniques in Puget Sound

Nearshore habitats are critical habitat for fish and a wide variety of other organisms in the Salish Sea, and have been highly impacted by construction of erosion control structures. Recovery of Pacific salmon, several species of which are listed on the Endangered Species Act, is one current management goal. Soft shore protection has been increasingly applied in Puget Sound, but careful assessment and engineering criteria was lacking. The National Research Council investigated techniques nationally in 2007, with limited information. Additionally, site and drift cell assessment methods have not been previously defined to address these issues. The WDFW, WSDOT, WDOE and other partners who make up the Aquatic Habitat Guidelines group initiated the MSDG, published in 2014. The MSDG was developed to provide a comprehensive framework for site assessment and alternatives analysis to determine the need for shore protection and identify the technique that best suits the conditions at a given site, including where no-action is appropriate. Quantitative data collection and performance assessment, including habitat benefits and impacts, was first completed for 25 case studies to augment other monitoring data. The new data included projects with beach nourishment, large wood placement, bank re-slope and re-vegetation, bulkhead removal, vertical bulkheads, and rock revetments. Case studies were selected to represent a range of physical conditions, drift cell context, and project age (all in place for over 3 years). The MSDG includes chapters on: Stewardship, Site Assessment, Coastal Processes Assessment, Alternatives Analysis, Technique-specific design guidance, Monitoring, and R&D. It is intended for use by designers, regulators, planners, and motivated landowners and contractors. These guidelines are intended to give readers an overview of all of the necessary elements to inform the development of project goals and provide tools to design and evaluate appropriate and environmentally responsible projects for marine shores in the Salish Sea