Western CEDAR Elwha nearshore ecosystem restoration: dam removal and shoreline armor removal

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Western Washington University
Western CEDAR
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Elwha nearshore ecosystem restoration: dam
removal and shoreline armor removal
Jamie Michel
Coastal Watershed Institute, United States*!-)%-)#(%,#/!34!,7!4%23(%$).34)454%/2'
Anne Shaer
Coastal Watershed Institute, United States!..%3(!:%2#/!34!,7!4%23(%$).34)454%/2'
Dave Parks
Crescent Environmental, United States#2%3#%.4%.6)2/.-%.4!,'-!),#/-
Chris Byrnes
Washington Dept. of Fish and Wildlife, United States(2)382.%3$&77!'/6
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Elwha Nearshore Ecosystem Restoration:
Dam Removal and Shoreline Armor Removal
Jamie Michel and Anne Shaffer, Coastal Watershed Institute; Chris Byrnes, Washington Department of Fish
and Wildlife; Dave Parks, Washington Department of Natural Resources
Salish Sea Ecosystem Conference 2018

Dams Alter Sediment Supply
Former 210’ tall Glines Canyon Dam
Removal Completed August 2014
Former 105’ tall Elwha Dam
Removal Completed August 2012

Pre Dam Elwha River Delta
1908
Historical Changes to Estuaries, Spits, and
Associated Tidal Wetland Habitats in the
Hood Canal and Strait of Juan de Fuca
Regions of Washington State. PNPTC, 2006

Sediment Starvation Exacerbates Erosion and
Results in ¾ Mile of Armor
1956

Continued Erosion Despite Armor
2011
Photo: USDA Farm Service Agency

Approximately 20,000,000 cubic meters
of material behind dams*- approximately
60% is sand/ silt, 40% is gravel/cobble
15 ft
Photos by John Gussman
Lake Mills August 2012
*80% from Lake Mills
A. Ritchie, ONP, J. Bountry and T. Randle, BoR)

2009
2015
River Delta Expansion

Derelict Armor Inhibits Beach Formation Process

Elwha Nearshore Restoration
Chronic Sediment Starvation Results in Loss of ~20 acre Estuarine Lagoon
Shoreline transition from sand/gravel to cobble/boulder substrate
Derelict armor adversely impacts estuarine/nearshore dependent species
-Spawning
-Foraging
-Migrating

Freshwater Bay Deposition

Beach Lake Erosion
2015
1950
(Photo: US National Archives)

Elwha Nearshore Restoration Project
Multiple Mobilizations to
remove exposed abandoned
shoreline armor from
3 acres of tidelands along
¾ mile of beach in front of
Conservation Property,
Tribal Reservation and
Private Landowner.

Beach Lake Acquisition and Restoration Project
Phase I Armor Removal Demobilization
8/19/2016

Beach Lake Acquisition and Restoration Project
Increase of LWD Recruitment and Retention

Beach Lake Acquisition and Restoration Project
1/4/2017 (+4’ MLLW Tide) Material Exposed After Winter Erosion. Note the armor
and concrete panels on beach, but also the armor extending out to -2’ MLLW.
Project is permitted and funded for multiple phases of armor removal to continue to
mobilize as armor emerges.

Sand Engine Technique in Holland
Stive, M.J.F.; de Schipper, M.A.; Luijendijk, A.P.; Aarninkhof, S.G.J.; van Gelder-Maas, C.; van Thiel de Vries, J.S.M.; de
Vries, S.; Henriquez, M.; Marx, S., and Ranasinghe, R., 2013. A new alternative to saving our beaches from local sea-level
rise: the sand engine. Journal of Coastal Research, 29(5)
2013
1970’s
1990’s
2011
Completion of 20 M cubic
meter Sand Engine in 2011

Beach Lake Acquisition and Restoration Project
Monitoring Metrics
-Newly Emerged Armor
-Beach Topography
-Beach Sediment Size
-Forage Fish Spawning
-Beach Wrack
-Invertebrates
-Fish Use
-LWD

Project Supporters and Collaborators
2 Grade
Excavation and
Development

Questions/What’s Next?