Puget Sound Nearshore Ecosystem Restoration Project Restore America s Estuaries Conference 2012 Tampa, FL

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1 Restore America s Estuaries Conference 2012 Tampa, FL presented by: Theresa Mitchell, WA Dept. of Fish & Wildlife

2 Nearshore General Investigation

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4 Change Analysis: Comparison of historical and current shoreline conditions Chambers Estuary (Pierce County, WA) Photo of Chambers Creek mouth ca 2011, from Microsoft Bing.

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6 1. Barriers in large river deltas restrict the movement of fresh water and tides. So, what s wrong with the Nearshore? Barriers in large river deltas restrict the movement of fresh water and tides Shorebirds need large river deltas and nearshore wetlands to rest and fuel up as they migrate through Puget Sound to their northerly breeding grounds. 1

7 1. Barriers in large river deltas restrict the movement of fresh water and tides. 2. Small coastal inlets have been blocked off and filled in Small coastal inlets have been blocked off and filled in 2 Salmon need large river deltas, small coastal inlets, and shallow water areas to rest, feed, and hide from predators.

8 1. Barriers in large river deltas restrict the movement of fresh water and tides. 2. Small coastal inlets have been blocked off and filled in Armoring of beaches and bluffs 3. Armoring along beaches prevents and bluffs replenishment prevents sediment of from replenishing beaches and beaches intertidal and areas intertidal areas Bulkheads can prevent sediment from coastal bluffs from reaching the shoreline, resulting in fewer and smaller beaches. 3

9 1. Barriers in large river deltas restrict the movement of fresh water and tides. 2. Small coastal inlets have been blocked off and filled in Nearshore wetlands have been 3. Armoring eliminated along beaches and bluffs prevents sediment from replenishing Loss of nearshore beaches wetlands makes intertidal areas 4 shorelines more vulnerable to the effects of sea level rise because 4. Nearshore wetlands help wetlands absorb energy have been from eliminated storms, waves, and high flows.

10 1. Barriers in large river deltas restrict the movement of fresh water and tides. 2. Small coastal inlets have been blocked off and filled in Shoreline has become shorter, 3. Armoring along beaches simpler, and bluffs and prevents more artificial sediment from replenishing beaches and Loss intertidal of nearshore areas habitat has ecological, economic, recreational, and cultural effects: fewer salmon to catch, fewer clams to harvest, and fewer 4. Nearshore wetlands have been eliminated sandy beaches to enjoy. 5. Shoreline has become shorter, simpler, and more artificial 5

11 1. Barriers in large river deltas restrict the movement of fresh water and tides. 2. Small coastal inlets have been blocked off and filled in Many places are affected by 3. Armoring multiple along types beaches of changes. and bluffs prevents sediment from replenishing beaches and intertidal areas 6 While small scale alterations may be insignificant by themselves, cumulative impacts build over time, compounding 4. Nearshore wetlands have been eliminated the adverse effects. 5. Shoreline has become shorter, simpler, and more artificial 6. Many places are affected by multiple types of changes.

12 PSNERP identified 4 strategies to guide efforts in Puget Sound.

13 Strategy Analysis results can be spatially viewed.

14 Strategy Analysis results can be spatially viewed.

15 What should we do?

16 IDEAS

17 Project Characteristics Project Name Lat & Long Nearshore Database Description Management Measure(s) Increase the acreage of salt marsh and tidal channels through removal of dike material at 2 sites. Tidal channel networks will be partially excavated. Berm or Dike Removal or Modification Channel Rehabilitation or Creation

18 Nearshore Database View spatial extent of project ideas

19 Projects near Seattle, WA Use initial screening tools Seattle

20 Overlay project ideas with strategy recommendations (right action, right place) Coastal Inlet Strategy

21 Verification of project details Recommendation for PSNERP to proceed with 10% design? Yes/No Sufficient description and consistent with strategy(s) and objective(s) Opportunity to restore process to a less degraded state

22 Harper Estuary Restoration Element Restoration Treatment SE Olympiad Drive Remove roadway, culvert, fill, and boat ramp. Debris and Fill Tidal Channels Remove brick clinker piles, relict roadway embankment, and bulkhead Fill linear ditch. Excavate new tidal channels Vegetation Utilities Plant riparian vegetation in disturbed areas. Relocate utilities associated with SE Olympiad Dr.

23 Developed Model to quantify ecological benefits Area* [(Process 2 + Structure + Function)/max score] Used designs to develop cost estimates Performed cost effectiveness evaluation

24 PRELIMINARY IDENTIFIED PROJECTS 19 Recommended Projects Combination of delta, embayment, and beach ~5,300 acres (area of restored process) ~$1.5B total project cost (construction, real estate, PED, monitoring & contingency) meet other program goals (e.g. salmon recovery)

25 Candidate Site Evaluation Criteria Addresses Strategy (contributes towards objectives) Feasibility Technical (Engineering) Social Cost Effective Ecosystem Benefits Risk & Uncertainty

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