Erosion
Erosion is a natural and essential process in the Salish Sea
that helps shape and maintain the region’s dynamic shorelines.
Over time, wind, waves, tides, and rainfall gradually wear away bluffs and banks, depositing and transporting sediment along nearby shores. This constant movement of material nourishes beaches, builds spits, and supports the formation of marine & nearshore habitats. Without erosion, many of the Salish Sea’s beaches would not exist or would slowly shrink over time. While often viewed as destructive, natural erosion plays a critical role in sustaining the coastal ecosystems and recreational spaces that define this unique marine environment.
Erosion is a natural process
Erosion is a natural and essential process in the Salish Sea that helps shape and maintain the region’s dynamic shorelines. Over time, wind, waves, tides, and rainfall gradually wear away bluffs and banks, depositing and transporting sediment along nearby shores. This constant movement of material nourishes beaches, builds spits, and supports the formation of marine & nearshore habitats. Without erosion, many of the Salish Sea’s beaches would not exist or would slowly shrink over time. While often viewed as destructive, natural erosion plays a critical role in sustaining the coastal ecosystems and recreational spaces that define this unique marine environment.
Feeder Bluffs are Beach Builders
Feeder bluffs play a key role in building and maintaining local beaches by providing sand and gravel through natural erosion. Protect your property by keeping structures away from the bluff and managing runoff with vegetation to prevent erosion and support wildlife habitat.
Human Drivers of Erosion
While erosion is a natural and necessary process to maintain habitats and species, rates can also be accelerated by our actions.
Feeder Bluff Examples Map
This interactive map shows various feeder bluffs and other coastal landforms around the Puget Sound.
Drift Cells
Most beaches within the Sound and Salish Sea lie within littoral or “drift” cells. While there may be seasonal changes in the directional movement of sediment, the dominant direction of transport within a particular cell is determined by the net long-term transport of sediment along segments of the shoreline. These are formed by a variety of factors including wind, sediment supply, and sediment sinks. This can lead to different beaches gaining or losing sediment over time. Beaches with no net transport are often found within pocket beaches and are usually associated with rocky shorelines. Long stretches of hardened and modified shorelines will also be designated as having “no appreciable drift due to the lack of sediment supply lost to the armoring. Due to the complex coastlines of the Salish Sea, drift cells here can vary greatly. There are over 800 drift cells in Washington State! (Source: Shore Friendly; Shipman 2008)
Find the drift cell direction and other features for your beach on the Department of Ecology Coastal Atlas.
Managing Erosion
Managing erosion in a natural way focuses on working with coastal processes rather than against them. Instead of relying on hard structures like seawalls or bulkheads—which can disrupt sediment flow and worsen erosion elsewhere—natural erosion management uses softer, more adaptive approaches. These include planting native vegetation to stabilize bluffs, restoring sediment to absorb wave energy, managing surface water flow and drainage appropriately, and allowing space for shorelines to shift gradually. In some areas, removing unnecessary shoreline armoring can help beaches recover and improve habitat for fish, birds, and other wildlife. By supporting these nature-based strategies, communities around the Salish Sea can protect property and infrastructure while preserving the natural beauty and ecological health of the coast.
Shore Friendly Living Video: Managing Shoreline Erosion
Resources
Yard Waste and Steep Slopes
Improper yard waste disposal on steep slopes can destabilize bluffs, smother vegetation, and trigger landslides—learn why this common practice is risky and how to manage steep terrain safely.
Landslide Warning Signs and Triggers
Washington experiences hundreds to thousands of landslides each year, causing significant damage to roads, property, and the environment. Discover the causes, warning signs, and resources available to help reduce landslide risk and protect your community.
Managing Erosion as a Shoreline Landowner
Scroll to page 26 and beyond to better understand the natural processes driving erosion and how to safely manage it on your shoreline property.
