Salish Sea Ecosystem Conference

Shore armor removal for nearshore restoration

Shore armor, such as bulkheads, rock revetments, and seawalls can negatively impact ecological function and impair nearshore processes in coastal systems. Recent mapping conducted by CGS for the ESRP Beach Strategies project estimated that armor is present on 29% of Washington shores of the Salish Sea, and this value likely underestimates the actual presence of armor in some regions. When functioning as nature intended, Salish Sea shores provide vital foraging, refuge, and rearing habitat for juvenile salmonids and many other species. Negative impacts of shore armor include reduced sediment input from feeder bluffs that is needed to sustain down-drift beaches and spits, direct burial of the backshore and sometimes the intertidal beach, and altered wave and sediment transport dynamics. Together these impacts result in a simplification of the shoreline, reduced beach width, and loss of nearshore habitat area. In many cases shore armor has been found to be unnecessary and alternatives to hard structures do exist; under these circumstances shore armor and coastal structures can be removed and the beaches and bluffs of the coastal system returned to their natural, functioning state. Several case studies of recent, successfully implemented shore armor removal projects will be outlined, featuring project identification, prioritization, assessment, feasibility, design, construction oversight, and monitoring, with a focus on lessons learned. Project sites have varied between high wave energy settings to protected low wave energy sites. The talk will also cover the needed partnerships between agencies and organizations to complete these projects, some of which have taken four or more years to complete. We are currently designing 19 bulkhead removal projects—showing that these projects are happening at an increasing rate.