Mariners Cove Eelgrass Transplant & Dredge for Mariners Cove Beach Club; Whidbey Island, WA: 2018 – Present

Mariners Cove is a residential community whose marina requires periodic dredging to maintain access. As part of a larger contract with Mariners Cove’s residential community to facilitate dredging permits and mitigation, Marine Surveys & Assessments developed and implemented an eelgrass (Zostera marina) management and mitigation plan, which consisted of multiple Submerged Aquatic Vegetation (SAV) surveys to ensure minimal habitat impact, including eelgrass bed delineation and density surveys, reconnaissance for eelgrass transplant sites, transplant site selection, and a baseline transplant/reference site eelgrass density survey. Using the best available scientific methods, eelgrass within the dredge footprint was transferred to the adjacent pre-determined transplant site in a single day/tidal cycle to minimize stress on the transplanted eelgrass and to maximize the success of the transplanting efforts. MSA wrote the Eelgrass Transplant and Monitoring Plan and is currently conducting post-transplant monitoring surveys to ensure that eelgrass density meets the survivorship criteria.

Before dredging, MSA supervised sediment coring; completed a sediment Sampling Analysis Plan (SAP); conducted a Chemical Analysis; and produced a Sediment Characterization Report (SCR), a Biological Evaluation (BE), a Water Quality Monitoring Plan, and a Dredge & Disposal Plan. Permits handled by MSA for this project include a JARPA, a State Environmental Policy Act (SEPA) analysis, a DNR Right of Way permit (ROW), an Island County Conditional Use Permit (CUP), and a Master Land Use Application. The dredge spoils were utilized as beach nourishment along the upper beach northeast of the channel entrance, where it was determined that the sediment placement would enhance existing forage fish spawning habitat and perpetuate continued sediment input farther down the shoreline, following the natural coastal processes of the net shore-drift cell. Forage fish spawning surveys were conducted along the beach prior to the dredge spoils placement. MSA worked with regulators to develop a survey protocol for the subsequent monitoring that is occurring to track beach elevations and help bolster understanding of sediment transport following beach nourishment.