River Delta Restoration

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This page is a synthesis page to organize information about the ongoing Restoration of Puget Sound River Deltas. The focus is on the chronology of work, pointing to more detailed information on Place pages for individual River Deltas, as well as some information on shift in restoration strategy and Funding mechanisms. A separate page is need to describe Urban River Delta Restoration in the Duwamish Estuary and Puyallup Estuary

Early Activity (1996-2005?)

Initial restoration efforts were opportunistic.

• Spencer Island Restoration in 1994 was among the first large scale restoration actions in Puget Sound, documented in Tanner et al 2002. In the same period of time, acquisition of large parcels by Snohomish County in the lower delta set the stage for latter work. Other small dike breaches in the Snohomish were funded by mitigation at Marysville Mitigation Site and Spencer Island Mitigation Site
• Deepwater Slough Restoration on WDFW land in the Skagit Delta was the first restoration in the Skagit Delta resulting in a mixed use site crossed by dikes as a compromise between restoration and duck hunting interests.
• Restoration planning by the Skagit River System Cooperative, culminating in Greene & Beamer 2005 identified an empirical basis for estuary restoration as a crucial part of Skagit salmon recovery and led to long term support for Skagit Estuary monitoring under the Intensively Monitored Watersheds effort. This body of work from SRSC set the tone for future work in estuaries across Puget Sound.
• The Nisqually Tribe led projects in Red Salmon Slough in the Nisqually Delta began with a mitigation action and a small dike removal.

The First Wave of Broad-scale Delta Restoration (2005-2012?): Quilcene, Skokomish and Nisqually

• Puget Sound Nearshore Ecosystem Restoration Project was a large scale planning project which ran from 2001 until 2015 with the authorization of a feasibility report by the US Congress. It provided a sequence of analysis which described the relevance and loss of large river delta wetlands in Puget Sound, and established "process-based restoration" as a regional goal.
• The Estuary and Salmon Restoration Program was first authorized in the 2006 state capital budget, in response to work by PSNERP, and created a large state resource that could strategically provide multi-million dollar awards to support delta restoration. This funding source began supporting the evaluation of delta restoration effectiveness, and was critical to Nisqually, Skokomish and following efforts.
• Meanwhile Quilcene Delta restoration was quietly advancing by the Hood Canal Salmon Enhancement Group under a series of projects. While smaller and less researched than Nisqually or Skokomish, the Quilcene restoration was part of a leading edge of large scale dike setbacks.
• Skokomish Restoration 2005-2017
• Nisqually Delta restoration remains the single largest restoration action in Puget Sound, and was significant because it was a $15-20M project, funded by federal stimulus spending during the economic collapse of 2008-09 (along with the Elwha dam removals). It was the first "large scale" project, and inspired development of

Shifting Tools and Tactics

• Inspired in part by the Nisqually Refuge Restoration the Puget Sound Acquisition and Restoration large capital projects program, which brought large blocks of state capital funding to bear on river delta projects, reinforcing ESRP as a funder of substantive estuary projects. Before ESRP and PSAR, only federal USACE Continuing Authority Programs provided these levels of funding.
• Wiley Slough Restoration in the Skagit Delta restored flooding, but local farmers claimed that modification of drainage systems caused damages to crops. A culvert failed due to design and construction problems, and shoaling in the delta obstructed drainage pathways. This ongoing conflict refocused attention on the tensions between the operations of agriculture, restoration of tidal flooding, and the cultural divides between fish and farm communities.
• The Skagit Tidegate Fish Initiative was a pivotal regulatory agreement negotiated by NOAA and several parties around trade offs between continued operation of tidegates and recovery of delta rearing Chinook salmon. NOAA agreed to not pursue a claim of "adverse modification of critical habitat under ESA as long as recovery projects continued to be advanced in the system. A credit trading system was developed to track the agreement.
• Skagit Drainage and Fish Initiative, not unlike Skagit TFI, the DFI followed a regulatory conflict over maintenance of drainage ditches with fish access. A shared set of specifications and best management practices have
• Estuary Vital Sign was adopted by the Puget Sound Partnership Leadership Council in ##
• Cereghino 2015 is a report that attempts to assess
• Fisher Slough Restoration was a relatively expensive project per acre, but pioneered multiple benefit work, by upgrading agricultural drainage systems, providing flood control benefits, and working closely with the local farming community.
• Stillaguamish

Restoration of the Lower Snohomish Delta (2015-2023?)

• See Snohomish Estuary

The Challenge of Massive Scale Estuary Restoration: Whidbey Basin

Whidbey Basin Deltas account for 60% of historical vegetated tidal wetlands (Simenstad et al 2011). These systems also form the foundations of remaining Puget Sound Agricultural Production, as well as the core populations of Puget Sound salmonids, including two species listed under the Endangered Species Act.

• A more detailed topic page summarizing restoration monitoring in the Whidbey Basin is found at Whidbey Basin Estuary Restoration Monitoring
• The emergence of Floodplains by Design funding in the state capital budget, and Resilience Funding in the federal budget, followed by increasing focus on multiple benefits in the National Estuary Program's Implementation Strategies work has led to the funding of diverse project elements.
• Farm, Fish and Flood Initiative in the Skagit Delta has been a sometimes controversial approach to restoration project development, because it involves a diverse community in considering the costs and benefits of projects to multiple constituencies. It reviews a large population of projects using a multi-criteria decision process and system wide hydrodynamic modelling.
• Stillaguamish Delta Restoration
• Estuary Implementation Strategy