Shannon Point Revetment Removal Feasibility and Restoration Alternatives
Presentation Abstract
Coastal Geologic Services assessed the feasibility of removing nearly 800 ft of large boulder rock and fill from the intertidal. The rock revetment was an apparent abandoned railroad causeway cut from bedrock and filled along the intertidal portion of a bluff backed beach just south of Shannon Point in Anacortes, Skagit County, Washington. This restoration project was previously identified in a restoration prioritization report by CGS (2008) as a high priority for habitat benefit, but removing approximately 2,500 cubic yards of boulder and fill from the beach presents many challenges. Several issues needed to be considered and flushed out if this project was to proceed smoothly. These issues included, variable ownership within and surrounding the project area, balancing full restoration goals of project proponents with cost effectiveness and future trail options for Parks, and foreseeable permitting requirements such as method of removal – over land or by barge, the nature of a small wetland area confined between the base of the bluff and the rock revetment, and slope stability. The range of issues to investigate and address here are representative of the challenges associated with nearshore restoration feasibility projects throughout the Salish Sea. Background data investigation and site assessment determined the feasibility of removal actions and informed restoration alternatives. Site access was secured by the project proponents. Site assessment included several visits to the site for reconnaissance, topographic survey and rock quantities estimate, and detailed slope stability assessment. Three restoration alternatives were produced including: 1. Full Restoration entailing removal of all revetment rock and fill, 2. Full Rock Revetment Removal, and 3. Partial Rock Revetment Removal. Maneuvering through challenges presented in the feasibility stage of the project to the recommended restoration alternative and design (currently in process) for Shannon Point will be the focus of this presentation.
Session Title
Session S-02G: Reimagining Shorelines
Conference Track
Shorelines
Conference Name
Salish Sea Ecosystem Conference (2014 : Seattle, Wash.)
Document Type
Event
Start Date
1-5-2014 5:00 PM
End Date
1-5-2014 6:30 PM
Location
Room 6C
Genre/Form
conference proceedings; presentations (communicative events)
Contributing Repository
Digital content made available by University Archives, Heritage Resources, Western Libraries, Western Washington University.
Subjects – Topical (LCSH)
Shorelines--Washington (State)--Anacortes; Restoration ecology--Washington (State)--Anacortes
Subjects – Names (LCNAF)
Coastal Geologic Services; Shannon Point Marine Center
Geographic Coverage
Salish Sea (B.C. and Wash.)
Rights
This resource is displayed for educational purposes only and may be subject to U.S. and international copyright laws. For more information about rights or obtaining copies of this resource, please contact University Archives, Heritage Resources, Western Libraries, Western Washington University, Bellingham, WA 98225-9103, USA (360-650-7534; heritage.resources@wwu.edu) and refer to the collection name and identifier. Any materials cited must be attributed to the Salish Sea Ecosystem Conference Records, University Archives, Heritage Resources, Western Libraries, Western Washington University.
Type
Text
Language
English
Format
application/pdf
Shannon Point Revetment Removal Feasibility and Restoration Alternatives
Room 6C
Coastal Geologic Services assessed the feasibility of removing nearly 800 ft of large boulder rock and fill from the intertidal. The rock revetment was an apparent abandoned railroad causeway cut from bedrock and filled along the intertidal portion of a bluff backed beach just south of Shannon Point in Anacortes, Skagit County, Washington. This restoration project was previously identified in a restoration prioritization report by CGS (2008) as a high priority for habitat benefit, but removing approximately 2,500 cubic yards of boulder and fill from the beach presents many challenges. Several issues needed to be considered and flushed out if this project was to proceed smoothly. These issues included, variable ownership within and surrounding the project area, balancing full restoration goals of project proponents with cost effectiveness and future trail options for Parks, and foreseeable permitting requirements such as method of removal – over land or by barge, the nature of a small wetland area confined between the base of the bluff and the rock revetment, and slope stability. The range of issues to investigate and address here are representative of the challenges associated with nearshore restoration feasibility projects throughout the Salish Sea. Background data investigation and site assessment determined the feasibility of removal actions and informed restoration alternatives. Site access was secured by the project proponents. Site assessment included several visits to the site for reconnaissance, topographic survey and rock quantities estimate, and detailed slope stability assessment. Three restoration alternatives were produced including: 1. Full Restoration entailing removal of all revetment rock and fill, 2. Full Rock Revetment Removal, and 3. Partial Rock Revetment Removal. Maneuvering through challenges presented in the feasibility stage of the project to the recommended restoration alternative and design (currently in process) for Shannon Point will be the focus of this presentation.
