Erosion On Beaches

The Basics

Most Puget Sound beaches have low to moderate erosion rates; few are in high-erosion zones. These are mostly places with heavy winds and high waves, such as the western side of Whidbey Island and some south-facing beaches. Sand spits, which are made of fine sediment deposited by the currents, can also be subject to heavy erosion and flooding.

What Should I Know?

Factors that can increase beach erosion:

  • Increased wave action due to armor on neighboring property
  • Removal of beach vegetation
  • Onsite beach armoring causing scouring

On beaches, native plants and drift logs help dissipate wave energy. Without the interference of bulkheads and seawalls, beaches will usually erode gradually but will also be replenished by sand and sediment from nearby bluffs and beaches. This process provides healthy habitat for species ranging from insects to salmon to orcas.

Ironically, bulkheads can lead to more rapid erosion of beaches in some cases. While these structures can provide some erosion protection on your property, they contribute to overall beach loss by reducing the sediment supply. And when waves reflect off a bulkhead, they scour the area at its base and on adjoining beaches. Over time, an entire stretch of beach will become coarser, with less sediment and more gravel. The bulkhead could also eventually crack, tilt, or collapse.

What Should I Do?

You can reduce erosion risk on your beach by following proven management practices—such as ensuring that rainwater and roof runoff are diverted away from slopes, leaving trees and vegetation intact, adding native plantings, and building stairs and trails in a way that allows for natural erosion but doesn’t aggravate it.

A qualified coastal professional can evaluate erosion risk on your beach and suggest measures you can take to protect your property.

“The onsite visit was a real eye-opener. You can read about shoreline management and even study about it, but unless things are physically pointed out nothing really changes. The changes we are making will definitely improve the quality of our shorelines on Hood Canal.” —Steve Levette, Madrona Homeowners Association

On Beaches


  • Divert rainwater and runoff away from slopes
  • Leave native trees and vegetation intact
  • Add native plantings
  • Build stairs and trails to allow for natural erosion


  • Remove native trees and vegetation
  • Build trails straight down to the beach