Mission

The overarching goal of the Elkhorn Slough Tidal Wetland Project (TWP) on the central California coast is “to conserve and restore sustainable estuarine habitats in the Elkhorn Slough watershed through the application of an ecosystem-based management approach."

Specifically, the TWP seeks to enhance understanding of different conservation strategies and select preferred actions to achieve its vision for “a mosaic of estuarine communities of historic precedence that are sustained by natural tidal, fluvial, sedimentary and biological processes in the Elkhorn Slough watershed as a legacy for future generations.”

Objectives

Within the scope of the overarching goal, the TWP has three more-focused objectives:

• Conserve the existing highest quality estuarine habitats and native biodiversity by aiming for a more natural rate of habitat change.
• Restore and enhance the estuarine habitats of Elkhorn Slough. Aim for the natural distribution, extent and quality of Elkhorn Slough habitats with special emphasis on habitats with the highest loss rates.
• Restore and enhance the natural processes (hydrologic and geomorphologic) of Elkhorn Slough and its watershed to sustain a more stable and resilient estuarine system. Emphasize the roles of natural sources, transport, circulation, filtration and storage of water and sediment.

Seventeen planning principles were articulated by the Strategic Planning Team during the Tidal Wetland Project planning process to guide the effort’s decision-making, including:

• Keep a watershed perspective.
• Consider of the widest array of potential approaches.
• Accommodate economic interests and activities.
• Minimize the need for ongoing maintenance.
• Adapt management.
• Prioritize projects that could improve water quality.

Lead Organizations

Key Parties

The Elkhorn Slough Tidal Wetland Project (TWP) on the central coast of California has enlisted over one hundred individuals from different interests and areas of expertise to facilitate its science-based multi-stakeholder effort to restore important salt marsh habitats in Elkhorn Slough.

In addition to the Elkhorn Slough National Estuarine Research Reserve (NERR), which is owned and managed by the California Department of Fish and Game (DFG) in partnership with the National Ocean and Atmospheric Administration (NOAA), and the Elkhorn Slough Foundation, representatives from the following agencies and organizations participate in the TWP:

• California State University-Monterey Bay
• US Geological Survey
• University of San Francisco
• University of California-Davis
• Moss Landing Marine Laboratories
• Monterey Bay National Marine Sanctuary
• Monterey Bay Aquarium Research Institute
• California Department of Fish and Game-Monterey
• Moss Landing Harbor District
• US Army Corps of Engineers-San Francisco County
• California Coastal Conservancy
• California Coastal Commission-Central Coast
• US Environmental Protection Agency
• County Board of Supervisors
• University of San Francisco
• The Nature Conservancy
• Regional Water Quality Control Board-Central Coast
• National Marine Protected Areas Center (NOAA)
• Ocean Conservancy
• California Department of Parks and Recreation
• Union Pacific Railroad
• Stanford University
• Point Reyes Bird Observatory
• Cabrillo College
• Philip Williams and Associates Ltd.
• H.T. Harvey and Associates
• Bay Modeling

The Elkhorn Slough Tidal Wetland Project on the central California coast was initiated to reduce tidal scour and restore critical eroding salt marsh habitats in a manner that minimizes impacts on diverse ecosystem components, is based on the best available science and supported by a wide range of community interests.

The effort is managed by staff at the Elkhorn Slough National Estuarine Research Reserve (NERR) - jointly operated by the National Oceanic and Atmospheric Administration (NOAA) and the California Department of Fish and Game (DFG) - in partnership with a Strategic Planning Team and Science Panel.

• Core project team members include the TWP Coordinator from the NERR, NERR Research Coordinator, NERR Reserve Manager (from DFG), NERR Geographical Ecologist, Executive Director of the Elkhorn Slough Foundation (ESF), a senior scientist and a policy analyst from the Monterey Bay Aquarium Research Institute, and Director of the Ocean and Coastal Policy at the Nicholas School of the Environment at Duke University (formerly the Director of the Coastal Ocean Values Center of the Ocean Foundation). NERR staff members oversee the project’s administration and implementation, and serve as liaisons between the reserve, the TWP’s institutional participants, subcontractors and other stakeholders.
• The Strategic Planning Team is the primary decision-making body for the project comprised of representatives from regulatory and resource management agencies, conservation organizations, scientists, local government officials, marine-focused strategic planners, social scientists, landowners and harbor and boating interests. This group is responsible for developing criteria for habitat goals for the estuary, attending or jointly holding meetings with the Science Panel, providing input on background materials, and evaluating and prioritizing management strategies.
• The Science Panel reviews scientific information and provides the Strategic Planning Team with guidance on technical matters and is comprised of a broad spectrum of disciplinary and interdisciplinary experts who are knowledgeable of biological, ecological, hydrodynamic, geological and physiochemical processes, some of whom have previous experience with estuarine restoration.
• Working groups comprised of members of the Strategic Planning Team and Science Panel convene on matters of ecology, outreach, monitoring, hydrodynamics, conceptual modeling, modeling advising, historical ecology, ecosystem-based management and the Parsons Slough restoration option. The groups are currently being reorganized and new groups are now being formed.

Other important players in the EBM effort include the Elkhorn Slough Foundation (ESF) and various contracted institutions and consultants. In addition, NERR docents, local community members and peer reviewers participate. Authority to make management decisions and implement project plans varies among TWP participants. The SPT is the decision-making body for the TWP, but it serves more of an advisory role to the TWP participants with actual jurisdiction or land ownership in the area (i.e., DFG and ESF). 

The Elkhorn Slough watershed in central California has a history of environmental initiatives. Beginning in the 1980s, the slough was designated as an ecological asset by federal and state agencies. At this time, strategic land acquisitions were made for conservation purposes by the Elkhorn Slough Foundation, The Nature Conservancy, and others. In the 1990s, erosion and nutrient runoff from steep hillside farms adjacent to the slough became a top environmental priority.

The US Department of Agriculture and the Elkhorn Slough Foundation conducted community outreach and education to increase environmental awareness of better land use practices amongst farmers and the visiting public, and together with Sustainable Conservation they developed a one-stop regulatory program for permitting that facilitated farmers’ voluntary implementation of conservation measures on their land.

In 1999, The David and Lucile Packard Foundation awarded funding to The Nature Conservancy to develop a conservation plan for Elkhorn Slough. Through a process that involved more than two dozen stakeholders, a plan was drafted that identified coastal marsh habitat as a critical resource within the watershed, and it identified loss and conversion of marsh habitat, and contamination and sedimentation of remaining marshes, as major threats to the ecosystem.

In 2002, staff at the Elkhorn Slough National Estuarine Research Reserve (NERR), which is jointly operated by the California Department of Fish and Game (DFG) in partnership with the National Oceanic and Atmospheric Administration (NOAA), acknowledged the scale and complexity of the slough’s environmental issues and the need for coordinated input and action from scientific experts, resource managers and community members. Building on past efforts to preserve and restore the ecosystem, the NERR and partners wrote a proposal to the NOAA Coastal Impact Assistance Program for resources needed to initiate a stakeholder-driven science-based process that would develop a coherent and comprehensive vision for the slough and address the spectrum of threats impacting the wetland.

The proposal was approved; however, its budget was significantly scaled back from several million dollars to approximately $2-300,000. As a result, NERR staff scaled the project down and chose to prioritize the threats they perceived to be the most urgent and unaddressed, and that were within their capacity to mitigate given existing resources. They chose to focus, for the time being, on restoration options that will address tidal scour and loss of salt marsh habitat.

The Ecosystem

Elkhorn Slough is the largest tract of tidal salt marsh outside of the San Francisco Bay remaining in California today.The slough itself is a 2,690 acre (10.9 km²) wetland that extends 7 miles (11.3 km) inland from Monterey Bay in central California, which provides important resources to more than 780 species of resident and transient wildlife species, including a disproportionate number of rare, threatened, or endangered species.

In 1979, the National Oceanic and Atmospheric Administration designated 1,439 acres (5.8 km²) of the slough as a member of its National Estuarine Research Reserve program, and since that time large investments have been made in the area for conservation purposes.

The watershed encompassing Elkhorn Slough and nearby Moro Cojo Slough covers approximately 30,292 (122.6 km²) acres and is largely undeveloped with a quarter of the land adjacent to the slough in cultivated agriculture.

The Moss Landing Harbor, located at the entrance of the slough, is one of the most active fishing ports in the state and the area has become an increasingly popular destination for outdoor and nature-based recreational activities.

Several marine research institutions are located in and around the slough, and three highways and a main north-south coastal railroad intersect the waterway. In addition, the largest electricity-generating power plant in California is located at the slough’s mouth.

Threats

In the past, Elkhorn Slough was heavily impacted by erosion and nutrient run-off from steep hillside farms. Through outreach efforts to local farmers, conservation easements and the development of a one-stop regulatory permitting package that enabled farmers to implement voluntary conservation measures on their land, these issues have largely been mitigated.

Today, the slough is considered one of the most threatened ecosystems in California because of the magnitude of its tidal scour and rate of salt marsh habitat loss. Ninety percent of the historic salt marsh area is predicted to disappear by 2050 if no action is taken.

The tidal erosion and marsh loss threats have been attributed to alterations of tidal flow and sediment supply, traced back to 1947 when the mouth of the slough was relocated for the construction of the Moss Landing Harbor. In addition, historical diversion of upland riversforagricultural purposes has reduced downstream flow of fine sediment that traditionally replenished the estuarine plain.

Complementing past efforts to preserve and restore land in and around Elkhorn Slough on the central California coast, the Elkhorn Slough Tidal Wetland Project (TWP) was initiated in 2004 to re-establish important salt marsh habitats in a manner that minimizes impacts on the ecosystem as a whole, is based on the best available science and supported by a variety of community interests.

Strategies employed in the process include:

• Consideration of Alternative Actions: To select the best strategy for habitat restoration, four alternative projects were developed simultaneously, which provided stakeholders with options and allowed the project team to weigh the benefits, drawbacks and tradeoffs of each approach.
• Investigation of Similar Cases: The project team investigated restoration projects in areas addressing similar threats, which enabled them to learn from related initiatives’ experiences.
• Using Locally-Derived Data to Inform Predictions:The multi-stakeholder project team conducted physical, biological and socio-economic studies that enhanced their understanding of the ecosystem and informed their predictions for future conditions of the slough under each restoration scenario.
• Pilot Project Implementation and Adaptive Management: In 2009, a small restoration option was chosen as the most politically and financially feasible given current circumstances. In addition to slowing the rate of salt marsh loss, it will serve as a learning opportunity for future, potentially larger-scale restoration efforts and it will be adaptively managed over time.
• Public Consultations: To inform the public about the TWP, the impetus for it and its objectives, and to allow stakeholders to provide input on potential restoration strategies, the TWP team held several community meetings and led field tours of the slough.
• Use of Visuals to Convey Complex Ideas: To convey complex ideas and explain the ecology of the estuary and potential restoration options to non-technical audiences, conceptual models, Geographic Information System (GIS) maps, and diagrams were used during public consultations and TWP Strategic Planning Team meetings.
• Internet as a Communication Tool: The internet and Elkhorn Slough National Estuarine Research Reserve’s website were used as fora for sharing information and products generated by TWP team members, which helped ensure management transparency and allowed community members to provide input. Data from tide stations and the Land/Ocean Biogeochemical Observatory network were also made available on the website. In addition, the general public is informed of TWP progress, and working partnerships and relationships formed through the TWP process are sustained, through monthly project bulletins sent via email to over 600 people.
• Marine Protected Areas: To facilitate conservation of key estuarine resources, three marine protected areas (MPAs) were established in and around Elkhorn Slough in 2007 as part of the Marine Life Protection Act Initiative, which is creating a state-wide network of MPAs in fulfillment of the Marine Life Protection Act (1999). The MPAs in and around Elkhorn Slough – the Elkhorn Slough State Marine Reserve, Elkhorn Slough State Marine Conservation Area and the Moro Cojo Slough State Marine Reserve – were established along with 27 other MPA’s in the central California coast region as part of this MLPA initiative, not as part of the TWP directly.

The Elkhorn Slough Tidal Wetland Project (TWP) on the central California coast was initiated to restore critical eroding salt marsh habitats in a manner that minimizes impacts on a variety of ecosystem components, is based on the best available science and supported by a wide range of community interests. 

As of June 2009, a restoration project was chosen that will both slow the rate of marsh loss and serve as a learning opportunity for future restoration projects. A low sill – water control structure – will be constructed at the entrance of the Parsons Slough complex, a component of Elkhorn Slough.

Before, during and after the sill’s construction, water quality, biological community composition, marsh habitats and erosion rates will be monitored and subsequent data will be combined with input from scientific advisors and the community. This information will then be reviewed by project team members and relevant resource managers.

The design of the sill will serve as a baseline structure that will be compatible with future additions in height and the degree of tidal restriction, which will enable the project team to carefully evaluate the trade-offs of further tidal restriction over the course of several years and, specifically, assess the sill’s impacts on sediment loss, water quality and wildlife in Parsons Slough.

This incremental approach will provide an opportunity to gradually restore a portion of Elkhorn Slough while updating expectations of outcomes for potential larger restoration options based on measured changes.

The Elkhorn Slough Tidal Wetland Project (TWP) on the central California coast was initiated to restore important subsiding salt marsh habitats in a manner that minimizes impacts to the ecosystem as a whole, is based on the best available science and supported by a range of community interests.

This effort is building on three decades of past environmental initiatives in the area. Past efforts mitigated the impacts of erosion and nutrient runoff from steep hillside farms adjacent to the slough and strategically acquired land for conservation purposes. Since initiation of the TWP in 2004, project team members and the community have come together to discuss their visions for the system and explore strategies for restoring important salt marsh habitats.

Much progress has been made towards attaining a better understanding of the Elkhorn Slough ecosystem as a variety of studies have been conducted on the area’s hydrology, nutrient and sediment dynamics, wildlife populations and socio-economic values, which helped parameterize models being used to make predictions of future conditions in the slough under different restoration scenarios.

In 2009, a decision was made to proceed with the construction of a water control structure at the entrance to the Parsons Slough complex, a component of Elkhorn Slough. The structure will allow adaptive management and will inform future considerations of larger restoration options. Construction will soon be underway.

In addition, the TWP has joined other EBM initiatives in creating an EBM network on the US west coast of the United States, and knowledge gained regarding EBM implementation is being shared with interested parties through a variety of venues. 

The Tidal Wetland Project in Elkhorn Slough on the central California coast was initiated to restore critical eroding salt marsh habitats in a manner that minimizes impacts on a range of ecosystem components, is based on the best available science and supported by a wide range of community interests

It has been facilitated by five key factors:

• History of Multi-Objective Management: Estuary management has historically been focused on multiple objectives, and consideration has often been given to the interactions between systems and of human influences on the resources due to the nature of the landscape as an interface of land and sea and hub of human activities, respectively. As a result, the EBM effort in Elkhorn Slough developed organically.
• Small Scale: The size of the Elkhorn Slough ecosystem has made the TWP manageable relative to larger estuaries because there are fewer stakeholders to engage and many of them have a history of interacting with one another.
• Local Marine Science Research Institutions: The TWP has benefitted from its proximity to several world-class marine science research institutions. The area is relatively data-rich and local scientists have contributed significantly to discussions regarding the health of the slough, restoration strategies and potential outcomes of different restoration scenarios.
• State Legislation: Elkhorn Slough is in a region that supports holistic management approaches as the state of California has led the country in passing legislation encouraging marine ecosystem-based management approaches.
• Grant Funding: Grant funding has made the EBM effort at Elkhorn Slough possible as it has been the primary means of support for the Tidal Wetland Project to date.  

The Elkhorn Slough Tidal Wetland Project (TWP) on the central California coast was initiated to restore important subsiding salt marsh habitats in a manner that minimizes impacts on a range of ecosystem components, is based on the best available science and supported by a range of community interests. 

The TWP’s efforts have been challenged by a number of issues:

• Complexity: The complexity of wetland ecosystems caused by high environmental variability and scientific uncertainty have made it difficult to establish an understanding of baseline conditions in the slough and make predictions for future conditions under each alternative restoration scenario. The complexity of administrative activities associated with managing a multi-stakeholder effort is also challenging because participating individuals represent different and sometimes contradictory objectives and are operating on different timelines, so contributions of input, data and resources may be out of sync.
• Balancing Tradeoffs: Project team members have struggled with evaluating tradeoffs between different ecological goals and stakeholders’, sometimes conflicting, objectives.
• Dealing with Uncertainty: While Elkhorn Slough is relatively data-rich, knowledge gaps remain regarding ecosystem functioning and viability of restoration options in the face of climate change. Such uncertainties complicate discussions of tradeoffs and selection of management actions.
• Integrating Natural and Social Science: The integration of natural and social science data has been tricky as few mechanisms are currently in place within the TWP to incorporate disparate types of information.
• Lack of Authority: While some of the TWP participants have authority over land within the project area, no single entity has the authority to authorize the construction of a new ocean inlet or sill at the Highway 1 bridge because these projects cross multiple jurisdictional boundaries. Consequently, restoration options may be limited to TWP participants’ properties and large scale efforts may not be feasible.
• Funding Constraints: Limited, unsustainable grant funding has constrained the TWP’s ability to address ecosystem threats beyond the prioritized issue of salt marsh habitat loss, and its dependence on grant funding limits its capacity to capitalize on opportunities when they present themselves and ensure project activities will be sustained in the long-term.

The Elkhorn Slough Tidal Wetland Project (TWP) on the central California coast was initiated to restore important salt marsh habitats in a manner that minimizes impacts on diverse ecosystem components, is based on the best available science and supported by a wide range of community interests. 

Through the TWP process, project team members have learned:

• It is important to have a coordinating agency and local research capacity: It is important to have a non-profit or coordinating agency established as the nucleus of the effort, and having local scientific capacity to thoroughly study the area is critical.
• Bureaucrats facilitate implementation: While scientific involvement is essential, having a process driven by scientists can be difficult since many prefer to avoid advocacy and risk. Implementation of the TWP has been facilitated by hiring bureaucrats.
• Acknowledge uncertainty: Being upfront about uncertainty is important to ensure stakeholders are not surprised by unexpected outcomes, which could compromise trust.
• Some research should precede other research: While initiating both natural and social scientific studies simultaneously enabled the TWP multi-disciplinary team to learn from each other, the social scientists found that their research on environmental services and policy considerations would have been bolstered if the ecological data had been collected beforehand. 
• Personality is important: The personalities of participants greatly influence the trajectory and dynamics of the effort. A diplomatic leader that respects each stakeholder and validates their concerns facilitates the process by enhancing legitimacy, and having a close-knit group of people who are already committed to the place ensures dedication to the project and likelihood of continued interactions.