Restoration in Lower Plaquemines Parish: Maximizing Co-benefits for Protecting Critical Infrastructure and Communities through Ecosystem Resilience
Plaquemines Parish is located in the Greater New Orleans region of Louisiana and is home to several coastal communities, highly valued oil and gas infrastructure, and marsh, tidal, and riverine ecosystems. The region is acutely vulnerable to tropical storms, land subsidence, sea level rise, and increasing temperatures, which has amplified concerns about potential impacts on coastal habitats, communities, and industries, including fisheries and oil and gas. To protect its $50 billion worth of energy infrastructure in the region that is at risk to sea level rise and wave-induced erosion, the Shell Oil Company requested that the Water Institute of the Gulf create a community engagement planning process to advance nature-based solutions and build community resilience. This project will protect critical energy infrastructure, restore and enhance habitats and ecosystem functions for commercial fisheries and wildlife, and sequester carbon.
The lower Plaquemines Parish is home to several coastal communities, habitats, and industries such as fisheries and oil and gas. The region is vulnerable to several climate and non-climate factors, including sea level rise, storms, erosion, and habitat alteration. The lower Plaquemines Parish has the highest rate of land subsidence and sea level rise of all the parishes in Louisiana. Efforts to protect communities and infrastructure from coastal hazards within the parish have altered important coastal processes that protect communities (e.g., sediment accretion of beaches, draining of wetlands). There is increasing recognition in the area that protection and restoration efforts need to include nature-based options, such as building marshes, marsh terraces, ridges, and river siphons, rather than hard infrastructure solutions that can be cost-prohibitive and ineffective over the long term. In addition, ongoing activities such as the ongoing dredging maintenance of the Mississippi River undertaken by the U.S. Army Corps of Engineers (USACE) may be leveraged to support nature-based efforts. The dredged material is usually deposited offshore or in a designated disposal area nearshore.
In addition to ecosystem services at risk from climate change (e.g., fisheries, recreation, shoreline buffering capacity), there is highly valued oil and gas infrastructure that may be damaged with projected sea level rise and wave erosion, including the Shell Oil Company’s $50 billion worth of energy infrastructure in the region. Shell approached The Water Institute of the Gulf to partner on a project to develop nature-based solutions that build community resilience while using the USACE dredged material to restore wetland habitats. The Water Institute led a public engagement process to incorporate community input into the design of restoration projects, and are now leveraging private and public funding to implement solutions that are agreeable to diverse stakeholders.
The restoration project was designed to explore synergies and efficiencies for maximizing benefits from funds invested by state, federal, local, non-profit, and research partners. The goals of the project are threefold: (1) to maximize restoration efforts for the local community and project partners; (2) to leverage a federal funding opportunity through USACE Beneficial Use of Dredged Material (BUDMAT) program; and (3) to engage the U.S. Fish and Wildlife Service and the Louisiana Department of Wildlife and Fisheries. If these goals are fully implemented, the project will be able to maximize habitat creation, restoration, and maintenance and protect critical infrastructure.
In order to provide restoration options for the community to consider, The Water Institute developed an Integrated Biophysical Model in Delft3D (Basinwide Delft3D) and an Integrated Compartment Model (ICM). These numerical models assess the ability of proposed projects to respond to projected environmental and climate variables and are especially suited to run long-term future scenarios (i.e. water flow, water height, and salinity). The Water Institute also used resources from the National Oceanic and Atmospheric Administration, and bathymetry and vegetation datasets. Carbon measurements from these models and datasets allow for the comparative assessment of potential carbon storage potential between different projects. Shell is interested in creating verified carbon credits in a blue carbon marketplace (e.g., for sequestering carbon in a restored marsh) to offset emissions occurring through regular operations. Another financial benefit of the blue carbon market is that these offsets can be sold in the voluntary carbon market, which could help cover the cost of monitoring and maintaining the project over time. In addition to modeling, The Water Institute held public meetings and conducted outreach to determine adaptation and restoration options. After The Water Institute developed a series of options, the project team identified key stakeholders to participate in a series of workshops designed to gather community perspectives and identify locations where restoration efforts could best reduce vulnerability and increase resilience in the parish.
Workshop participants were guided through specific prompts, such as:
- Identify places of high social, cultural or economic value;
- Describe problems or threats that stakeholder groups and communities face;
- Describe potential nature-based solutions to be included in the Coastal Master Plan;
- Identify nature-based solutions for specific sites;
- Categorize the desired outcomes that motivate projects in different sites; and
- Identify specific benefits or constraints associated with the implementation of different solutions.
Outcomes from this exercise were documented, allowing for the collection of a range of local knowledge to inform key issues and concerns for the future development and monitoring of projects. Forty-five project ideas were identified from the workshops.
The qualitative data gathered were incorporated into a geospatial dataset, allowing researchers to compare local input with existing assessments of proposed ecological restoration projects. The proposed restoration projects aim to maximize sediment retention and allow for a controlled freshwater and sediment flow to build land with minimal impacts to riverine industries and estuarine fisheries. Some of the co-benefits of proposed restoration projects identified by the stakeholders include:
- rebuilding habitats and reducing vegetation loss;
- controlling hydrology and preventing salinity intrusion;
- providing storm surge protection and land building benefits for the community, infrastructure, natural resources, and ecotourism; and
- improving quality of life, estuarine longevity, wildlife population maintenance, protection of infrastructure, and enhancement of river navigation.
The Water Institute helped the community select a suite of projects to be considered for funding through the Louisiana Coastal Management Plan program. The state is looking to include model projects for its 2023 Coastal Master Plan, particularly those that address issues related to sea level rise and subsidence and provide risk reduction benefits at the community or regional scale. The Plaquemines Parish government, on behalf of the full partnership involved in the restoration project, submitted the final outputs of the local knowledge workshops to the Coastal Protection and Restoration Authority for consideration. The entire project will most likely be funded through a patchwork of private, federal, state, and local funds. A number of partners are involved in this project including the Barataria-Terrebonne National Estuary Program, Louisiana Sea Grant, Plaquemines Port Harbor, and Terminal District, Plaquemines Parish Council, tourism businesses, and local fishing and seafood business task forces.
Outcomes and Conclusions
A recent challenge has been a slowdown in work due to the COVID-19 pandemic, resulting in a delay in project implementation. Limited staff capacity is also a barrier for when working with parishes, but The Water Institute and partners work closely to build trust and engage the community. Community outreach was key in determining restoration options and selecting projects for implementation. The project timing also coincided with a critical need to protect oil and gas infrastructure, providing support from both industry and the community. If full funding can be secured, the project could be completed in about a year. The next steps include expanding this effort to additional Louisiana parishes, focusing on urban flooding, green infrastructure, and public-private partnerships for co-benefits in restoration and resilience.
Sims, S.A., Braddock, K.N., and Gregg R.M. (2021). Restoration in Lower Plaquemines Parish: Maximizing Co-benefits for Protecting Critical Infrastructure and Communities Through Enhanced Ecosystem Resilience. [Case study on a project of The Water Institute of the Gulf]. Product of EcoAdapt’s State of Adaptation Program. Retrieved from CAKE: Retrieved from CAKE: https://www.cakex.org/case-studies/restoration-lower-plaquemines-parish-maximizing-co-benefits-protecting-critical-infrastructure-and-communities-through-ecosystem-resilience (Last updated October 2021)