Restoration In Louisiana Research Articles

Leveraging co-production within ecosystem restoration to maximize benefits to coastal birds

Coastal Louisiana's ecosystems are threatened by anthropogenic factors exacerbated by climate change induced sea-level rise. The 2010 Deepwater Horizon oil spill resulted in injuries and deaths to coastal birds in Louisiana, and the ongoing loss of habitat has limited the potential for successful nesting of resident birds throughout the coast. Habitat loss is being addressed through increased large-scale ecosystem restoration as a result of settlement funds from the Deepwater Horizon oil spill. To further inform bird restoration in Louisiana, an avian restoration guidance document (Guidance for Coastal Ecosystem Restoration and Monitoring to Create or Improve Bird-NestingHabitat, 2023) was developed to maximize restoration benefits for coastal breeding birds while also achieving broader habitat restoration objectives. The developed restoration guidance was co-produced by subject-matter experts and professionals, including avian experts, engineers, and coastal restoration project managers. The result of this cross-disciplinary effort was specific and targeted guidance that presents designable habitat features that are in the control of project engineers and are also important high-value bird nesting habitats (e.g., shoreline access, elevation heterogeneity and edge habitat). For the first time in Louisiana, defined nest-site characteristics and monitoring approaches are readily available to inform ecosystem restoration project implementation. The restoration document specifically emphasizes bird species that breed and nest in coastal habitats in Louisiana, and restoration managers can use these guidelines to explicitly incorporate bird nesting habitat features into coastal restoration planning, design, and implementation. In developing this guidance, many knowledge gaps and data needs were identified specific to engineering and project design, enabling the research community to frame research questions around specific coastal restoration questions. The co-production of science model applied here for avian resources is applicable to a wide range of other living marine resources that may benefit from large-scale ecosystem restoration and is an example of the benefits of working relationships, communications, and common goal setting.

Restoring human freedoms: from utilitarianism to a capability approach to wetland restoration in Louisiana’s coastal master plan

Coastal restoration is being undertaken globally to address and avoid the losses caused by rising relative sea levels and other forms of coastal ecosystem degradation. Restoration decision-making is increasingly considering its social impacts, but how social factors should be incorporated in decision-making is a matter of debate. Multi-criteria approaches are promoted for their ability to overcome problems associated with monetary valuation of nature. Louisiana’s coastal restoration program has been promoted as a good example of a multi-criteria approach. This article engages in a critical examination of the wetland restoration program contained in Louisiana’s 2017 Coastal Master Plan (CMP). The principles that underlie decision-making, and how these principles are deployed through decision tools and metrics, constitute an implicit utilitarianism. This utilitarianism, in spite of the use of multiple criteria, recreates problems commonly associated with monetary valuation, namely, it creates poor distributional outcomes and fails to account for non-economic values of nature. The study argues that these problems can be overcome with a systematic use of the capability approach. This would involve the development of an evaluative framework that prioritizes the freedoms of the worst-off, and translation of this framework into a series of metrics compatible with planning models and tools. The paper closes by outlining some challenges to achieving a capability approach in Louisiana’s CMP.

Tradeoffs in habitat value to maximize natural resource benefits from coastal restoration in a rapidly eroding wetland: is monitoring land area sufficient?

Louisiana contains nearly 40% of estuarine herbaceous wetlands in the contiguous United States, supporting valuable ecosystem services and providing significant economic benefits to the state and the entire United States. However, coastal Louisiana is a hotspot for rapid land loss from factors including hurricanes, land use change, and high subsidence rates contributing to high relative sea‐level rise. The Coastal Protection and Restoration Authority (CPRA) was established after major hurricanes in 2005 to coordinate coastal restoration in Louisiana and develop the Louisiana Coastal Master Plan. The LA Coastal Master Plan uses numerical modeling of multiple scenarios to select a suite of restoration projects based on maximum land area created and flood reduction (as proxies for ecosystem value). Using potential value to aquatic, terrestrial, and social resources, our work compared habitat value of shallow open water areas to emergent wetland. While potential resource benefits varied by emergent wetland salinity type and emergent wetland versus water, they were similar, suggesting that restoration planning based primarily on wetland land area may not achieve the maximum possible ecosystem benefits. After nearly 20 years of integrated restoration planning in coastal Louisiana, a reassessment of restoration planning decision drivers may be beneficial to ensure maximum benefits from coastal restoration. As a result of the Deepwater Horizon oil spill, settlement funds will be a major support to coastal restoration in Louisiana for many years. Assessing potential habitat value to multiple natural and social resources in Louisiana has potential to maximize synergy with large northern Gulf of Mexico restoration programs.

Geomorphologic change and patchy mud infilling in a sandy dredge pit in eastern Ship Shoal, Louisiana shelf, USA

To restore degraded barrier shorelines of the Mississippi River Deltaic Plain of Louisiana, sand is dredged from borrow areas in estuaries and continental shelves. The dredge pit in South Pelto Blocks 12 & 13 on eastern Ship Shoal used for Caminada-Moreau Headland restoration project is one of several sand dredge pits for barrier island restoration in Louisiana. Ship Shoal Sand Complex is in a sand-dominated, energetic, continental shelf environment. During energetic events, transient mud can blanket Ship Shoal, and then bypasses the shoal and deposits in deeper water. In this study, we collected and interpreted a suite of geophysical data from South Pelto Dredge Pit which is located in water depths of ∼9 m on eastern Ship Shoal. Repeat bathymetric survey data show that South Pelto Dredge Pit is presently infilling at an average rate of approximately 27,480 m3/year, which is slower than the predicted rate presented by an earlier numerical model. Side-scan mosaic maps indicate low-backscatter (muddy) sediments were transported into this pit and deposited in many patches within two years after dredging. The seabed inside this pit became smoother over time and the slope of the pit walls became gentler. Infilling of the South Pelto Dredge Pit seem to be controlled by sediment availability, which is volumetrically dominated by (a) far-field fluvial suspended sediment, (b) the adjacent seabed sediment resuspended by tides, waves, and currents, but presumably less impacted by (c) hurricanes or tropical storms during our study period of 2017–2018. The South Pelto Dredge Pit thus displays a unique mixing and redistribution of cohesive mud and non-cohesive sand. Initial spatial control on sediment infilling appears to be dictated by micro-bathymetry on the pit bottom created by the dredging activities. Bathymetric, side scan and grain-size data all indicate that mud was prone to deposit in the troughs.

Hydrodynamics, sediment transport, and water quality of two contrasting dredge pits on the Louisiana shelf

Sediment is needed for coastal restoration in Louisiana and is often excavated offshore from mud-capped and sandy dredge pits. To better understand the post-dredging effects on hydrodynamics, sediment transport, and water quality, two tripods were deployed at sandy Caminada pit and mud-capped Sandy Point pit in summer 2018 and 2019, respectively, and profiling data were collected during a total of 34 casts in 2018 and 2019. The results reveal similarities and differences between pit and adjacent waters and are used to compare two pits. Tropical storm events were observed during each deployment which provided insight concerning the effects these storms have on dredge pits. Water masses inside Caminada pit were relatively stable and sluggish which resulted from the pit's deep depth and location. Sandy Point dredge pit was highly impacted by the Mississippi River plume due to its proximity, which effectively stratified the water column in summer 2019, affecting ventilation near the seabed. Strong winds, taller waves, higher shear stresses, elevated turbidity and increased dissolved oxygen were generally found during the passages of tropical storms over both pits. Comparing with outside tripod station, the inside station of Caminada pit experienced a longer duration of low dissolved oxygen in bottom waters. Water mass movements and oxygen consumption from resuspension of pit bottom are likely key mechanisms driving oxygen dynamics. Our results provide observational data for future studies on post-dredging morphologic change, marine communities, and oxygen dynamics of dredge pits on the Louisiana shelf and other coastal dredge areas worldwide.

Strategies to improve implementation of adaptive management practices for restoration in coastal Louisiana

Natural resources of coastal Louisiana support the economies of Louisiana and the whole of the United States. However, future conditions of coastal Louisiana are highly uncertain due to the dynamic processes of the Mississippi River delta, unpredictable storm events, subsidence, sea level rise, increasing temperatures, and extensive historic management actions that have altered natural coastal processes. To address these concerns, a centralized state agency was formed to coordinate coastal protection and restoration effort, the Coastal Protection and Restoration Authority (CPRA). This promoted knowledge centralization and supported informal adaptive management for restoration efforts, at that time mostly funded through the Coastal Wetlands Planning, Protection and Restoration Act (CWPPRA). Since the Deepwater Horizon (DWH) oil spill in 2010 and the subsequent settlement, the majority of restoration funding for the next 15 years will come through one of the DWH mechanisms; Natural Resource and Damage Assessment (NRDA), the RESTORE Council, or National Fish and Wildlife Foundation –Gulf Environmental Benefit Fund (NFWF-GEBF). This has greatly increased restoration effort and increased governance complexity associated with project funding, implementation, and reporting. As a result, there is enhanced impetus to formalize and unify adaptive management processes for coastal restoration in Louisiana. Through synthesis of input from local coastal managers, historical and current processes for project and programmatic implementation and adaptive management were summarized. Key gaps and needs to specifically increase implementation of adaptive management within the Louisiana coastal restoration community were identified and developed into eight tangible and specific recommendations. These were to streamline governance through increased coordination amongst implementing entities, develop a discoverable and practical lessons learned and decision database, coordinate ecosystem reporting, identify commonality of restoration goals, develop a common cross-agency adaptive management handbook for all personnel, improve communication (both in-reach and outreach), have a common repository and clearing house for numerical models used for restoration planning and assessment, and expand approaches for two-way stakeholder engagement throughout the restoration process. A common vision and maximizing synergies between entities can improve adaptive management implementation to maximize ecosystem and community benefits of restoration effort in coastal Louisiana. This work adds to current knowledge by providing specific strategies and recommendations, based upon extensive engagement with restoration practitioners from multiple state and federal agencies. Addressing these practitioner-identified gaps and needs will improve engagement in adaptive management in coastal Louisiana, a large geographic area with high restoration implementation within a complex governance framework.

Ecosystem restoration in Louisiana — a decade after the Deepwater Horizon oil spill

Louisiana has a long history of coastal management and restoration actions with multiple projects implementing common approaches. Traditionally, most of the restoration efforts have been ongoing in Louisiana by state and federal agencies through the Coastal Wetlands Planning, Protection and Restoration Act (CWPPRA). These activities are now being expanded significantly through additional funding and implementing entities such as the Resources and Ecosystems Sustainability, Tourist Opportunities, and Revived Economies of the Gulf Coast States (RESTORE) Act of 2012 Council, National Resource and Damage Assessment (NRDA) through the Louisiana Trustee Implementation Group (LA TIG), and the National Fish and Wildlife Foundation (NFWF). Considering a broader ecosystem or landscape context for implemented restoration projects can provide a framework for emphasizing commonality of restoration goals. Such a framework allows for multiple benefits of restoration efforts to be quantified, including prioritized natural resources, ultimately assessing the effectiveness of large-scale restoration efforts in coastal Louisiana. Three disasters have completely changed the trajectory of Louisiana’s coastal resto- ration and protection program. Hurricanes Katrina and Rita (2005) compelled the state to take serious note of the vagaries of nature, especially high-energy events like hurricanes, and to develop a comprehensive/robust coastal protection and restoration plan. Five years later, the Deepwater Horizon (DWH) oil spill exposed the fragility of the Louisiana coast but at the same time penalty monies provided much needed funding to implement the state’s coastal protection and restoration plans. This paper provides a high-level assessment of project implementation and makes the case that Louisiana could move quickly in the implementation of various restoration plans because robust and comprehensive restoration plans were previously developed and are available. Here, it must be appreciated that for the first time, dedicated funding is available not only for regional programmatic monitoring to implement adaptive management, but also for development of the art and science of restoration. It is also suggested that for efficient and cost effective implementation of Louisiana’s Coastal Master Plan federal agencies must work in tandem with the state/CPRA who not only bring the most comprehensive plan but expertise along with institutional knowledge to the table.

Overview of statewide geophysical surveys for ecosystem restoration in Louisiana

The System Wide Assessment and Monitoring Program (SWAMP) was implemented by the Louisiana Coastal Protection and Restoration Authority (CPRA) to develop an Adaptive Management Implementation Plan (AMIP). SWAMP ensures that a comprehensive network of coastal data collection/monitoring activities is in place to support the development and implementation of Louisiana’s coastal protection and restoration program. Monitoring of physical terrain is an important parameter of SWAMP. For the first time a systematic approach was adopted to undertake a geophysical (bathymetric, side-scan sonar, sub-bottom profile, and magnetometer) survey along more than 5,000 nautical miles (nm) (excluding the 1,559 nm currently being surveyed from west of Terrebonne Bay to Sabine Lake) of track-line in almost all of the bays and lakes from Chandeleur Sound in the east to Terrebonne Bay in the west. This data collection effort complements the regional bathymetric survey undertaken under the Barrier Island Comprehensive Monitoring (BICM) Program in the adjacent offshore areas. This paper describes how a study of this magnitude was conceptualized, planned, and executed along the entire Louisiana coast. It is important to note that the initial intent was to collect bathymetric data only for numerical modelling for ecosystem restoration and storm surge prediction. Geophysical data were added for oyster identification and delineation. These first-order data also help comprehend the regional subsurface geology essential for sediment exploration to support Louisiana’s marsh and barrier island restoration projects.

Coastal monitoring and data management for restoration in Louisiana

The Coastal Protection and Restoration Authority (CPRA) of Louisiana was created after the devastating hurricanes of 2005 (Katrina and Rita) and is responsible for planning and implementing projects that will either reduce storm-induced losses (protection) or restore coastal ecosystems that have been lost or are in danger of being lost (restoration). The first task of the CPRA board was to develop Louisiana’s first Coastal Master Plan (CPRA 2007), which formally integrates and guides the protection and restoration of Louisiana’s coast. The System-Wide Assessment and Monitoring Program (SWAMP) was subsequently developed as a long-term monitoring program to ensure that a comprehensive network of coastal data collection activities is in place to support the planning, development, implementation, and adaptive management of the protection and restoration program and projects within coastal Louisiana. SWAMP includes both natural-system and human-system components and also incorporates the previously-developed Coastwide Reference Monitoring System (CRMS), the Barrier Island Comprehensive Monitoring (BICM) program, and fisheries data collected by the Louisiana Department of Wildlife and Fisheries (LDWF) in addition to other aspects of system dynamics, including offshore and inland water-body boundary conditions, water quality, risk status, and protection performance, which have historically not been the subject of CPRA-coordinated monitoring. This program further facilitates the integration of project-specific data needs into a larger, system-level design framework. Monitoring and operation of restoration and protection projects will be nested within a larger hydrologic basin-wide and coast-wide SWAMP framework and will allow informed decisions to be made with an understanding of system conditions and dynamics at multiple scales. This paper also provides an update on the implementation of various components of SWAMP in Coastal Louisiana, which began as a Barataria Basin pilot implementation program in 2015. During 2017, the second phase of SWAMP was initiated in the areas east of the Mississippi River. In 2019, development of SWAMP design was completed for the remaining basins in coastal Louisiana west of Bayou Lafourche (Figure 1). Data collection is important to inform decisions, however if the data are not properly managed or are not discoverable, they are of limited use. CPRA is committed to ensuring that information is organized and publicly available to help all coastal stakeholders make informed, science-based decisions. As a part of this effort, CPRA has re-engineered its data management system to include spatial viewers, tabular download web pages, and a library/document retrieval system along with a suite of public-facing web services providing programmatic access. This system is collectively called the Coastal Information Management System (CIMS). CPRA and U.S. Geological Survey (USGS) are also developing a proposal to create an interface for CIMS data to be exported to a neutral template that could then be ingested into NOAA’s Data Integration Visualization, Exploration and Reporting (DIVER) repository, and vice versa. DIVER is the repository that the Natural Resource Damage Assessment (NRDA) program is using to manage NRDA-funded project data throughout the Gulf of Mexico. Linking CIMS and DIVER will make it easier to aggregate data across Gulf states and look at larger, ecosystem-level changes.

Turning a tragedy into large-scale barrier island restoration in Louisiana: A three-project case study

Louisiana has successfully utilized the proceeds from the fines imposed for the Deepwater Horizon incident to significantly jump start barrier island restoration as identified in the Coastal Protection and Restoration Authority (CPRA) of Louisiana Coastal Master Plan (CPRA 2017). The Riverine Sand Mining/ Scofield Island Restoration (BA-40) project was the first to be implemented through a commitment of remaining funds in the initial emergency protective berms’ construction budget formulated into the Berms to Barrier Islands plan. The berm/ restoration conversion at Scofield Island was the first to utilize this funding mechanism. The Caminada Headland Beach and Dune Restoration–Increment II (BA-143) project was funded through the National Fish and Wildlife (NFWF) Gulf Environmental Benefit Fund and capitalized on a prior project constructed to the west completing the beach and dune restoration of the entire headland. Lastly, the Caillou Lake Headlands Restoration (TE-100) project was funded through the Natural Resource Damage Assessment (NRDA). The TE-100 project restored the entire degraded beach and dune system backed by a created marsh habitat to complement a prior restoration effort. Scofield Island is located west of the active Mississippi River bird’s foot delta in Plaquemines Parish, Louisiana. A primary objective of this project was the excavation and delivery of Mississippi riverine sand for beach and dune restoration; a first in our nation’s history. Multiple design and construction challenges arose requiring the CPRA, consulting team, and construction contractor to adapt. Construction of the beach and dune component of this project required approximately 22 miles (mi) of pipeline and four booster pumps along a sediment pipeline corridor that crossed two hurricane protection levees, went underneath two highways and a navigation channel, traversed the Empire Waterway, crossed Pelican Island, entered the Gulf of Mexico, and extended to Scofield Island. The restoration footprint length was approximately 2.4 mi, total volume placed was approximately 3.5 million cubic yards (MCY), and the benefit equaled 510 restored acres (CEC 2014). The pipeline corridor has subsequently been utilized for two other restoration projects, Shell Island East Berm Barrier Island Restoration (BA-110) and Shell Island West NRDA Restoration (BA-111). As a first in Louisiana’s restoration history, the Caminada Headland Beach and Dune Restoration–Increments I and II (BA-45 and BA-143) utilized sand dredged from Ship Shoal, an Outer Continental Shelf (OCS) sand resource located approximately 26-38 mi from the restoration areas. The 13.3 mi long headland was restored with approximately 3.7 MCY for BA-45 and 5.5 MCY for BA-143 from the borrow area (CEC 2015 and CEC 2017). A combination of cutterhead dredge/scow barges and hopper dredges were used to construct the project. A key goal of this project was restoring and protecting the fragile ecosystem which provides critical habitat for nesting shorebirds. The headland is of critical importance in serving as a defense of our national energy infrastructure. The western portion of the headland directly protects Port Fourchon, one of the nation’s most important energy ports. Caillou Lake Headlands (TE-100), known locally as Whiskey Island, is centrally located in the Isle Dernieres chain and it is a remnant of the single, larger Isle Dernieres (Last Island), which was segmented into multiple smaller islands by a major hurricane in 1856. The project included restoring the beach and dune along approximately 4.5 mi while simultaneously creating a marsh platform along approximately 5,500 feet (ft) utilizing 10.4 MCY of sand from the borrow area (CEC 2018). The borrow area lies within Ship Shoal OCS Lease Block 88 located over 10 mi along the conveyance corridor offshore of Whiskey Island. This project represents the largest barrier island restoration project to date in terms of volume per linear foot of shoreline with an average density of over 441 cubic yards per linear foot (CEC 2018).

Designing an environmental impact bond for wetland restoration in Louisiana

Coastal regions and deltas around the globe are seeking financing for resilience projects to cope with more frequent extreme events, sea-level rise and land subsidence. Interest is growing in natural infrastructure that generates multiple ecosystem services including flood risk reduction. The growth of the conservation finance market represents an opportunity to support these investments, but there is a need for pilot transactions that align incentives across private and public entities, along with rigorous performance metrics for natural infrastructure linked to resilience outcomes. We test the feasibility of the Environmental Impact Bond (EIB) model to address these challenges. An EIB is a form of Pay-for-Performance debt financing where investors provide upfront capital to implement a project and are repaid according to the degree to which desired environmental outcomes are achieved. We evaluate this concept for wetland restoration projects identified in Louisiana’s Coastal Master Plan by developing a site selection procedure and designing a multi-stakeholder transaction tied to restoration outcomes. Based on our proposed model we conclude that an EIB could be used to accelerate restoration and increase the net benefits of wetland investments, aligning incentives of the investors and payors around metrics of wetland sustainability.

Institutionalizing Coastal Restoration in Louisiana After Hurricanes Katrina and Rita: The Importance of Advocacy Coalitions and Claims-Making in Post-disaster Policy Innovation

Why do disasters sometimes lead to the creation of innovative, new policy frameworks? People often assume that this happens because disasters cause people to understand environmental problems in new ways. However, this case study of changes in Louisiana’s coastal land management policy after Hurricanes Katrina and Rita in 2005 tells a different story. After the hurricanes, state and federal legislators passed several laws that created a framework for comprehensive coastal restoration, replacing the haphazard and poorly funded approach that preceded the storms. This policy innovation occurred because the hurricanes created an opportunity to enact ideas developed by a coalition of coastal scientists, environmental attorneys, and local businesspeople during the previous three decades. Without the long-term work of this advocacy coalition, policy innovation would probably not have occurred. The case study presents the history of coastal restoration policy in Louisiana and explains how this history illustrates models of policy agenda setting from political science and environmental problems construction from sociology. In turn, these models provide a key to interpreting other examples of post-disaster policy change.

Coastal Restoration as Contested Terrain: Climate Change and the Political Economy of Risk Reduction in Louisiana

Although many studies have examined the effects of structural factors and institutional interests on risk estimation practices, little is known about the political dynamics surrounding divergent responses to risk reduction measures. This article examines the political economy of risk reduction, using a case study of Louisiana's coastal restoration planning and decision‐making process. Specifically, the article draws on documentary evidence, long‐term ethnographic field observations, and semistructured interviews to investigate the proliferation of risk conflicts and disputes surrounding the 2012 Louisiana Comprehensive Master Plan for a Sustainable Coast, the latest long‐term risk‐reduction plan to slow coastal erosion and achieve a sustainable coast. As I point out, coastal restoration in Louisiana is contested terrain where a variety of contentious groups struggle to influence and control debates over climate change risk and coastal erosion risk reduction. By examining the proliferation of contested risk definitions and risk reduction strategies in Louisiana, I aim to provide new insight into the organizational and institutional forces that shape positions on risk, the political‐economic forces that create and allocate risk, and the social construction of community identity and culture through risk debates.

Challenges of ecosystem restoration in Louisiana – availability of sediment and its management

Abstract. Human intervention has impaired the Mississippi River’s ability to deliver sediment to its delta wetlands, and as a consequence acute land loss in coastal Louisiana has resulted in an unprecedented ecocatastrophe. To mitigate this degradation, an unparalleled restoration effort is underway. For this effort to be successful and sustainable, various sediment input mechanisms must be integrated, including: building appropriate sediment-diversions; beneficially using the millions of cubic metres of sediment dredged annually from navigational channels; harvesting deposits of sand and suitable sediment from the river and offshore; and related sediment management activities that are compatible with other uses of the river. A comprehensive sediment management plan has been developed to identify and delineate potential sediment sources for restoration, and to provide a framework for managing sediment resources wisely, cost effectively, and in a systematic manner. The Louisiana Sediment Management Plan provides regional strategies for improved comprehensive management of Louisiana's limited sediment resources.

Public perceptions of wetland restoration benefits in Louisiana

AbstractKim, T-G., and Petrolia, D. R. 2013. Public perceptions of wetland restoration benefits in Louisiana. – ICES Journal of Marine Science, 70: 1045–1054. We conducted a referendum-style contingent-valuation survey to investigate public perceptions of wetland restoration benefits including storm protection, ecosystem services, and recreational benefits and to analyse willingness to pay (WTP) for large-scale coastal restoration in Louisiana. Results of the ordered probit and binary probit models indicate that the public perceives both a strong relationship between increased wetland loss and an increased storm risk and a substantial likelihood of increased storm-protection benefits from wetland restoration. However, respondents expressed that they were less likely to believe the improved storm reduction benefits from restoration when they perceived a high frequency of category 3 or greater storms. Additionally, we found that hurricane protection benefits were the most important factor explaining WTP for wetland restoration for preventing expected future land losses in coastal Louisiana.

Registration of Sea Oats Cultivars ‘LA12‐201’, ‘LA12‐202’, and ‘LA12‐203’

Sea oats (Uniola paniculata L.) is a perennial grass native to the Gulf of Mexico and Atlantic coasts that is commonly used to stabilize beaches. Three sea oats cultivars with excellent plant vigor, plant spread, and enhanced stem counts before and after major hurricanes were developed from seeds collected from natural growing areas of the United States: ‘LA12‐201’ (Reg. No. CV‐265, PI 665050), ‘LA12‐202’ (Reg. No. CV‐266, PI 665051), and ‘LA12‐203’ (Reg. No. CV‐267, PI 665052). LA12‐201, LA12‐202, and LA12‐203 are clonal cultivars that were tested in unreplicated and replicated field trials for 3 yr and compared with ‘Caminada’, an ecotype adapted to the north‐central coast of the Gulf of Mexico that is used extensively for beach restoration in Louisiana. LA12‐201 and LA12‐202 were as vigorous, dense, and tall as Caminada before and after a major hurricane, except on one evaluation date when both were denser and taller than Caminada. LA12‐203 was as vigorous, dense, and tall as Caminada on all evaluation dates. Amplified Fragment Length Polymorphism (AFLP) analysis of LA12‐201, LA12‐202, LA12‐203, and Caminada indicated that the three sea oats cultivars are genetically distinct. Due to their proven performance before and after major hurricanes, LA12‐201, LA12‐202, and LA12‐203 are recommended for beach restoration projects in the northern Gulf of Mexico coast.

A water and sediment budget for the lower Mississippi–Atchafalaya River in flood years 2008–2010: Implications for sediment discharge to the oceans and coastal restoration in Louisiana

Summary The Mississippi is the largest riverine system in North America and one of the most engineered rivers in the world. The challenges of studying the Mississippi River are due to its complex sediment–water dynamics and the multi (and often competing) uses for its resources. Flood control and navigation are primary factors that control how the river is managed. A third factor is the use of river resources, namely water and sediment, for nourishing the degrading coastal wetlands of the states of Louisiana and Mississippi. As such, these factors must be fully considered and coordinated while investigating and developing techniques to harness the sediment resources of the River for coastal restoration. This paper presents a detailed suspended sediment budget analysis for the lowermost Mississippi and Atchafalaya River systems for the flood years of 2008, 2009, and 2010. Data were derived mainly from Federal and State of Louisiana measurements of water discharge and suspended sediment load at (1) monitoring stations along the river channel and (2) boat-based measurements made during specific project studies at natural passes and man-made channel diversions. The present study was focused on flood years 2008–2010 to (1) minimize the influence on the budgets of a historical decline in sediment loads carried by the river as observed by previous investigators and (2) take advantage of recent improvements in the monitoring network. The results show that both the Mississippi and Atchafalaya distributary pathways were efficient at sequestering suspended sediments, particularly the larger (sand) size fraction. Approximately 44% of the total Mississippi + Red River suspended load (80% of the sand) reaching Old River Control structures split between the distributaries was sequestered upstream of the Gulf of Mexico by overbank storage and channel bed aggradation. Increases in bed aggradation in the Mississippi distributary are linked to a loss of stream power associated with man-made and natural exits upstream of the Gulf of Mexico. This further decreased the water and suspended sediment load reaching the deep water Gulf distributary exits in FY08–10 to 46% (water), 19% (total suspended load), and 1.4% (suspended sand). These patterns of sediment storage and delivery have major implications for channel dredging and river sediment diversions planned for Louisiana coastal restoration.

Freshwater river diversions for marsh restoration in Louisiana: Twenty-six years of changing vegetative cover and marsh area

[1] The restoration of Louisiana's coastal wetlands will be one of the largest, most costly and longest environmental remediation projects undertaken. We use Landsat data to show that freshwater diversions, a major restoration strategy, have not increased vegetation and marsh coverage in three freshwater diversions operating for ∼19 years. Two analytic methods indicate no significant changes in either relative vegetation or overall marsh area from 1984 to 2005 in zones closest to diversion inlets. After Hurricanes Katrina and Rita, these zones sustained dramatic and enduring losses in vegetation and overall marsh area, whereas the changes in similar marshes of the adjacent reference sites were relatively moderate and short-lived. We suggest that this vulnerability to storm damage reflects the introduction of nutrients in the freshwater diversions (that add insignificant amounts of additional sediments), which promotes poor rhizome and root growth in marshes where below-ground biomass historically played the dominant role in vertical accretion.

New Approaches to Sediment Management on the Inner Continental Shelf Offshore Coastal Louisiana

Abstract Coastal restoration in Louisiana requires clean sands for beach and dune restoration, whereas mixed sediments are required to rebuild marshes. The Louisiana coastal erosion problem is especially dire because it occurs on several fronts with the narrowing and overtopping of barrier islands and loss of back barrier bay and interior marshlands. Coastal restoration efforts in Louisiana depend on emplacement of sediment to build up barrier island and deltaic systems. Discovery of usable sediment is thus a vital factor in restoration efforts because up to 80% of some restoration project budgets can be allocated to exploration, exploitation, and emplacement of sediment. Because this cost is directly proportional to the distance of borrow sources from the project area, the cost-effectiveness of barrier island restoration and marsh creation depends on locating sufficient sediment volumes that are suitable for placement on beaches and dunes and for creating marshes. The restoration of Louisiana's barrier i...

Capturing Carbon Market Value from Coastal Wetland Protection and Restoration in Louisiana

Capturing Carbon Market Value from Coastal Wetland Protection and Restoration in Louisiana