Case Studies III: Skokomish River Ecosystem Restoration Washington State

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1 University of Massachusetts - Amherst ScholarWorks@UMass Amherst International Conference on Engineering and Ecohydrology for Fish Passage International Conference on Engineering and Ecohydrology for Fish Passage 2016 Jun 21st, 3:00 PM - 3:15 PM Case Studies III: Skokomish River Ecosystem Restoration Washington State Nancy Gleason U.S. Army Corps of Engineers Follow this and additional works at: Gleason, Nancy, "Case Studies III: Skokomish River Ecosystem Restoration Washington State" (2016). International Conference on Engineering and Ecohydrology for Fish Passage This Event is brought to you for free and open access by the The Fish Passage Community at UMass Amherst at ScholarWorks@UMass Amherst. It has been accepted for inclusion in International Conference on Engineering and Ecohydrology for Fish Passage by an authorized administrator of ScholarWorks@UMass Amherst. For more information, please contact scholarworks@library.umass.edu.

2 SKOKOMISH RIVER ECOSYSTEM RESTORATION WASHINGTON STATE Fish Passage 2016 Presenter: Nancy Gleason Mason County Skokomish Indian Tribe US Army Corps of Engineers

3 Overview Study Area Importance for Restoration Key Problems for USACE Focus Evidence for Problem Recommended Solution 2

4 Project Location: Lower Skokomish River Basin North Fork Mainstem South Fork Confluence Hunter Creek Weaver Creek

5 Significance Federal Interest Institutional Significance Technical Significance Public Significance Puget Sound estuary of national significance (EPA) Four ESA-listed salmon species represented in six unique populations 2 runs of salmon are already extirpated from the system Skokomish Tribe U&A Fishing Areas NMFS Essential Fish Habitat Skokomish River is largest source of freshwater to Hood Canal Salmon keystone species; indicators of overall ecosystem health Wetlands support unique flora and fauna; base of food chain habitat USFWS Biological Sampling Report critical limiting factors in the Skokomish River Basin Skokomish Watershed Action Team (SWAT) Puget Sound Partnership / Puget Sound Action Agenda Salmon Recovery Funding Board grant awards 4

6 Problems Unnaturally constricted river valley due to human structures Loss of natural floodplain functions & processes Loss of habitat quantity and quality Barriers to fish passage Lack of habitat complexity Lack of pools Degraded wetland & floodplain habitats Lack of woody debris Lack of riparian cover & vegetation 5

7 The Critical Problem

8 The Critical Problem

9 The Critical Problem

10 Evidence for Problem Excessive sedimentation with multiple causes: some natural, some human Salmon spawning river miles restricted to lower half of range due to subsurface flow No access to large wetland rearing habitat Declines in fish populations started same year as subsurface flows started

11 Recommended Plan Recommended Plan: Directly restores habitat for Federally listed salmonid species Improves quantity, quality, and complexity of habitat for multiple species Acres restored: 277 Total project first cost: $20 million Federal share: $13 million BUILDING STRONG Non-Federal share: $7 million + $10k annual O&M

12 Recommended Plan Features Confluence Levee Removal Benefits Restores year-round fish passage for ESA-listed species Alleviates a mile-long channel constriction Allows fish access to spawning grounds 11 11

13 Recommended Plan Features Wetland Restoration at River Mile 9 Benefits Reconnection and restoration of high-value forested wetland Provides spawning, incubation, rearing, and over-wintering habitats 12

14 Recommended Plan Features Wetland Restoration at Grange Benefits Reconnection and restoration of high-value forested wetland Provides spawning, incubation, rearing, and over-wintering habitats 13

15 Recommended Plan Features Side Channel Reconnection Benefits Provide refuge and rearing habitat for fish during high flows Expand the prey base for birds and mammals 14

16 Recommended Plan Features Upstream Large Woody Debris Benefits More frequent and deeper pools for spawning, rearing, and refuge habitat for juvenile and adult salmon Improves habitat complexity in the channel 15

17 Thank you! Nancy Gleason