A resource for shoreline property owners
An adequate setback with native trees and shrubs would
have helped protect this house from erosion. This bulkhead is ineffective
against upland erosion.
All repairs, replacements and new structures for shoreline protection whether it is anchored logs,
rip rap walls, bulkheads or any other device designed to slow or stop erosion,
requires a permit from the County.
State And Federal Requirements
The Washington Department of Fish and Wildlife & the Army Corp of Engineers
have additional permit requirements. Both use the
Joint Aquatic Resources Permit
Application (JARPA) form.
San Juan County Erosion 101:
- We have a very slow overall rate of erosion in the Islands. Much of our shoreline is rocky and is resistant to erosion.
- Native shoreline trees and shrubs help slow erosion and stabilize banks and
bluffs. When trees do fall into the water, they provide important nutrients,
shading, and habitat.
- Bluffs are rare in SJC and provide essential beach sustaining sediments. Natural
erosion is important for healthy shorelines.
- Bluffs are in a state of constant erosion. Rates of erosion will differ. All bluffs will have periodically large erosion events.
- Sediments are transported along the shore in what is called a drift cell:
- Begins at a site where erosion is producing sediment.
- Sediments continue to move along the shoreline within the transport area.
- Ends at a site where sediments are deposited, known as an accreting shoreline.
- Your property is a part of this dynamic shoreline process and should be a factor
in how you choose to develop.
Hard shore armoring was the traditional means of protecting
against erosion, but there are preferred new alternatives.
Bulkheads have documented negative impacts:
Experience has shown that
bulkheads may not resolve erosion issues; in fact they may create additional problems.
- Increased erosion on the landward side of the bulkhead can become unmanageable in some circumstances for property owners.
- As wave action continues along the altered shoreline beaches often lose their fine sands.
The resulting dead-pan beach, one of larger gravel and cobblestone, is less enjoyable.
- The loss of fine sediments is associated with the loss of forage fish spawning habitat.
Forage fish are essential to the diets of juvenile salmon.
- Bulkhead construction, ongoing maintenance and repairs are expensive.
What alternatives exist to address erosion on my property?
- Soft-shore armoring techniques are a professionally designed method of shoreline protection.
- Engineered to mimic the natural functions of beach processes.
- May include the utilization of native vegetation, large woody debris, beach nourishment (added
sands and sediments).
- Studies indicate their effectiveness in protecting the shoreline from erosion while promoting restoration of habitat.
Eroding beach on Blakely Island before restoration.
- Blakely photos courtesy of Jim Johannessen
Restored by Coastal Geological Services using soft shore
armoring techniques.
If you think your property is experiencing erosion consider:
This property appears to have had a large erosion event, possibly due to upland drainage issues.
- Is the bluff/bank presently stable?
- Are there signs of past instability (landslides)?
- Can you determine when the last landslide occurred?
- Is the bluff toe subject to wave attack?
- What is the nature and frequency of wave attacks?
- Is the shoreline in front of the bluff eroding or accumulating sands?
- What are the soil moisture and ground water conditions?
- What is the rate of bluff retreat?
- What materials comprise the bluff?
- What is the angle of the bluff?
- What vegetation is present?
- Is there surface water drainage over the bluff on the property or adjacent to the property?
- Is the property large enough for your purposes?
- Can the property be developed successfully without initiating or aggravating erosion?
- Would a greater setback of structures from the edge be safer?
To help you answer these questions, consider contacting a coastal geologist or
coastal engineer.
Resources:
How do I get information about my parcel?
- San Juan County's parcel search
provides basic information and aerial views of your property.
- The Washington Department of Ecology's Coastal Atlas offers aerial views of
coastline properties and GIS information about vegetation and habitat, slope stability and a variety of other physical and ecological features.