Presentation Abstract

Dam removal on the Elwha River exposed over 280 hectares of valley slope, terrace, and floodplain landforms covered in millions of cubic meters of sediments deposited before and during dam removal. These sediments are either extremely coarse in texture (sands, gravels and cobbles) or very fine (silt and clay) and range in depth from 0.5 to 20 meters. This unprecedented condition dictated an adaptive management approach to revegetation. A seven-year revegetation plan that included over 90 permanent plots monitored annually was implemented to provide management with insight into natural and managed revegetation progress in these distinctly different sediment surfaces. With a focus on the former Lake Mills reservoir, the larger of the two reservoirs de-watered as a result of dam removal, I will present six years of data from the permanent plots showing how sediment texture, planting and seeding influenced all aspects of vegetation recovery.

Session Title

Elwha Ecosystem Restoration: Emerging Lessons from a Comprehensive Project

Keywords

Revegetation, Elwha Reservoirs

Conference Track

SSE4: Ecosystem Management, Policy, and Protection

Conference Name

Salish Sea Ecosystem Conference (2018 : Seattle, Wash.)

Document Type

Event

SSEC Identifier

SSE4-704

Start Date

4-4-2018 2:00 PM

End Date

4-4-2018 2:15 PM

Type of Presentation

Oral

Genre/Form

presentations (communicative events)

Contributing Repository

Digital content made available by University Archives, Heritage Resources, Western Libraries, Western Washington University.

Subjects – Topical (LCSH)

Dam retirement--Environmental aspects--Washington (State)--Elwha River; Sediments (Geology)--Environmental aspects--Washington (State)--Elwha River; Revegetation--Washington (State)--Elwha River--Planning

Geographic Coverage

Elwha River (Wash.); 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

COinS
 
Apr 4th, 2:00 PM Apr 4th, 2:15 PM

Monitoring and adaptation management of revegetation in the former Elwha Reservoirs

Dam removal on the Elwha River exposed over 280 hectares of valley slope, terrace, and floodplain landforms covered in millions of cubic meters of sediments deposited before and during dam removal. These sediments are either extremely coarse in texture (sands, gravels and cobbles) or very fine (silt and clay) and range in depth from 0.5 to 20 meters. This unprecedented condition dictated an adaptive management approach to revegetation. A seven-year revegetation plan that included over 90 permanent plots monitored annually was implemented to provide management with insight into natural and managed revegetation progress in these distinctly different sediment surfaces. With a focus on the former Lake Mills reservoir, the larger of the two reservoirs de-watered as a result of dam removal, I will present six years of data from the permanent plots showing how sediment texture, planting and seeding influenced all aspects of vegetation recovery.