Earlier this summer the Delta Stewardship Council’s Delta Science Program’s Brown Bag seminar series presented three talks focused on habitat restoration to demonstrate how historical knowledge, natural processes and integrated planning and modeling will be critical components of reconciling the Delta to achieve the coequal goals and sustain the Delta as place. These noontime talks were part of the Joint Brown Bag Series sponsored by the Council, California Department of Fish and Wildlife’s Ecosystem Restoration Program and the State Water Resources Control Board’s Surface Water Ambient Monitoring Program.
“Together these talks covered considerable ground on the past, current and future Delta, how to plan for restoration, and quantify the effects of these projects in support of services society expects the Delta ecosystem to provide ,” said Rainer Hoenicke, Deputy Executive Officer of the Council’s (Council) Delta Science Program.
Lessons from the historical Delta
Using the past to inform current and future conditions was the general concept supporting the talk by Senior Scientist Robin Grossinger from the San Francisco Estuary Institute entitled Delta Landscape Metrics: Creating a Spatial Framework to Inform Restoration Planning. The Delta Landscape Project provides a landscape-scale perspective on restoration opportunities and recommendations founded on a sound understanding of the ecological functions that existed in the Delta prior to substantial human modification.
Historical data from the Delta Historical Ecology Study provide essential information on how the Delta system tends to function in response to physical processes and the conditions to which native species are adapted. This research provides a quantitative spatial framework to understand the physical environment and how it has changed over time and helps to inform restoration efforts which can be focused to enhance ecosystem function.
“Many are working on this challenge of how do we really do ecosystem restoration in the Delta,” Grossinger said. “That’s a tough assignment given the incredible transformation of the system over the past 100 years; it’s almost unrecognizable and yet we’re trying to create ecosystems and functional landscapes.”
The Delta Landscape Project will:
1. Define target ecological functions
2. Identify associated system attributes (spatial metrics)
3. Quantify landscape change metrics
4. Describe subregional potential (restoration opportunities based on physical drivers)
5. Create Conceptual Operational Landscape Units (the units characterize the combination of physical drivers and ecological functions)
6. Produce restoration guidelines and potential performance metrics
“Many of us are wrestling with the challenge of how do we make relatively small projects add up to functional systems over time,” Grossinger said. “The Delta Landscape Project, funded by the Ecosystem Restoration Program through the California Department of Fish and Wildlife is attempting to provide some of the tools to help us address that challenge.”
Lessons from the Cosumnes
Knowledge of the historic ecosystem provides a clearer understanding of the underlying ecological processes of a site or region and, with the incorporation of an adaptive management plan, can be used to develop restoration plans that have a higher chance of success. In the second talk of the series, Dr. Joshua Viers, associate professor from UC Merced, presented Ecosystem Quantification - Insights from Three Decades of Process-Based Restoration of the Cosumnes River Floodplain.
The Cosumnes River is the only river in the Sierra Nevada without a large dam and the only tributary of the Sacramento-San Joaquin River system that retains quasi-natural flow regimes. These flow characteristics have been the basis for a series of experiments focused on natural processes that return floodplain environments recently utilized for agriculture into active riparian ecosystems. The Cosumnes River Preserve was established in 1987, but a levee breach two years before put a natural force into motion that established an “accidental forest” and started a wave of research that continues to this day.
“That forest was the paradigm shift,” Viers said. “Wow; we could actually let rivers do the work; let rivers bring in the substrate, nutrients in the water and the germinates in order to establish some things from a horticultural perspective. Cosumnes is a scientific proving ground,” he added. “It’s of sufficient size to be meaningful, but small enough to be manageable from a scientific context – a bit of a sandbox.”
The processes studied at the Cosumnes Preserve represent complex biophysical interactions that shape the landscape and help reestablish early successional vegetation, generate habitat, and reconnect local hydrology.
“It provides an unprecedented opportunity to examine how rivers are intended to function from a fluvial and hydrological standpoint,” Viers said.
This research demonstrates that variable seasonal floods across flat agricultural floodplains can shape a topographically complex environment which provides a mosaic of conditions important for aquatic and terrestrial organisms. The goal of mimicking the dynamic processes and ecological functions characterized in these experiments has become the model for alluvial floodplain restoration in the region and can be a guiding principle for restoration throughout the Delta and its lower watershed.
Creating a ‘hub’ between projects
At the intersection of these two talks is the proposed Delta Restoration Hub. Campbell Ingram, Executive Director of the Delta Conservancy, discussed the Delta Restoration Hub – An Integrative Approach to Delta Restoration. The Hub concept is being developed by the Delta Restoration Network (DRN) and intends to address the challenges and integration needed to design and implement restoration projects to meet the coequal goals.
“The Hub will be a ‘situation room’ where people and resources are brought together to plan, model and develop restoration projects of varying sizes and level of connectivity across the Delta,” said Chris Enright, Senior Engineer with the Delta Stewardship Council and participant in the DRN.
Ingram posed the question, “What are we fundamentally trying to solve with the Hub?” and then answered it by highlighting what he sees Delta restoration planning currently lacking:
• Landscape-scale vision – The ability to really look at the landscape scale and make sure that all the ecological complexity, the current land use, agriculture and the communities in the Delta and the flood protection system are being accounted for.
• Sufficient, early engagement with the Delta community.
• Models, data inventory, and synthesis tools to support analyses, information sharing, and adaptive management.
• A standing expert restoration design team to: support timely, property-scale restoration planning; develop long-term restoration visions for restoration opportunity areas (which include combined physical drivers and ecological functions); and consider the Delta-wide effects and cumulative impacts of restoration projects over time.
A goal of the Hub is to address these issues and increase the collective ability to look across the landscape and make sure environmental complexity, current land use, and Delta communities are accounted for as habitat and ecological functions are restored. A sub-group of the DRN is developing funding mechanisms to support a three-year pilot demonstration Hub program. Ingram envisions offering restoration design services at no cost to individual project proponents. According to Ingram, the Hub will help ensure that best available science and adaptive management are incorporated into project designs thereby speeding up the overall restoration process and reducing costs.
“When viewed together, the path forward in the Delta will require the knowledge, insights, and integrated landscape perspectives presented in these three talks,” said Garrett Liles, Brown Bag coordinator and an environmental scientist in the Council’s Delta Science Program. “Although achieving a functioning reconciled future Delta and coequal goals will be difficult, it can happen if collaboration and best available science are the guide.”