Conserving and Restoring Critical Habitats

The Alabama Comprehensive Living Shorelines Monitoring Program was funded as part of the 2015 Funded Priorities List through the RESTORE Act. Awarded to the Dauphin Island Sea Lab and the University of South Alabama in 2021, this program aims to accomplish two main objectives. First, the program seeks to assess the efficacy of currently funded (and implemented) projects. Second, the program endeavors to develop and test standardized monitoring protocols that can be used to assess the performance of future living shorelines projects in the State and beyond. After receiving approval for the monitoring plan in early 2022, the teams commenced with their measurement campaigns. Our interdisciplinary team of scientists and engineers are monitoring 15 metrics across eight unique living shorelines projects in Alabama, most having paired controls nearby. The project sites cover a range of salinity regimes, wave energy exposures, shoreline characteristics, and reef/breakwater types. Measurement frequencies range from continuous to annual depending on the specific metric. While all sites will have measurements across all 15 metrics for multiple time periods, we are monitoring three of the eight sites more intensively. For example, we are continuously measuring water levels, wave characteristics, currents, bed levels, and water quality parameters at these so-called "sentinel" sites. These sentinel sites include Swift Tract, Salt Aire, and Northeast Point aux Pins. This presentation will provide a comprehensive overview of the monitoring program: the 15 monitoring metrics, the eight study sites and their controls, and the measurement frequency. We will provide specific examples of monitoring results that demonstrate the value of this program, as well as a summary of the positive impacts the program will have on the implementation of future living shorelines projects.

Natural shorelines provide ecosystem services that are integral to maintaining healthy and resilient coastal ecosystems and communities. However, anthropogenic and environmental stressors are reducing the extent of natural shorelines and, thus, their capacity to provide critical ecosystem services. Small-scale private property owners own an overwhelming majority of waterfront property in coastal Mississippi and Alabama. Therefore, environmentally-focused management of private shorelines can provide large-scale benefits. Unfortunately, the most common shoreline management strategies for private property owners are hardened structures (e.g., bulkheads and seawalls) that are known to impair coastal ecosystems. An alternative to hardened shorelines is living shorelines, which are a collection of shoreline stabilization techniques that incorporate natural materials such as native shoreline plants. To facilitate shoreline stewardship, the Mississippi-Alabama Sea Grant Living Shorelines Program and its partners began producing guidance documents, offering technical assistance, and conducting trainings for private property owners and contractors. Throughout these interactions, property owners and contractors have expressed their potential barriers to living shoreline adoption and needs (living shoreline research, communication, supplies, cost-share, and training). In this presentation, we will discuss the lessons-learned from activities as well as the status of addressing those barriers.

The Point aux Pins Living Shorelines Project is located along the northeastern portion of Point aux Pins. Funded under the Deepwater Horizon Oil Spill Early Restoration Framework Agreement, and implemented by the Alabama Department of Conservation and Natural Resoruces- State Lands Division, the project aims to offset injuries to primary and secondary productivity through the placement of a living shortelines breakwater. The project also has a secondary goal of reducing the rate of erosion through reduction of wave height and energy. The project consists of 15 breakwater segments that contain 39 wave attenuation units (WAUs) each. The WAUs were installed in the Fall of 2020 and the implementation of a 5-year post construction monitoring plan was initiated in Fall 2021. To date, 3 years of monitoring has been conducted for ADCNR by Stantec and DISL, with Monitoring Report being produced each year. This presentation will provide an overview of the project, the monitoring approach, and the monitoring results to date.

Natural shorelines are essential to maintaining a healthy ecosystem, but erosion accelerated by anthropogenic stressors greatly decreases the health of natural shorelines. Living shorelines are an alternative to shoreline hardening that protect and restore natural shorelines. However, many property owners and project designers do not know how to determine the best living shoreline solution for their location. To address this issue, the Virginia Institute of Marine Science created a living shoreline suitability model (LSSM) to inform living shoreline design recommendations in specific locations. This model has been applied to many waterbodies throughout the US, including the northern Gulf of Mexico, and uses data inputs such as fetch, land use, and bathymetry to categorize the shoreline. The LSSM uses fetch to calculate wave energy and classify the shorelines as "low, medium, or high" energy. However, many protected waterways (channels and rivers) have small fetch but high boat traffic, which has the potential to lead to under designed shoreline recommendations from the LSSM. To improve the recommendations produced by the model in restricted waterways, we collected wave energy data using low-cost wave gauges throughout Biloxi Bay and will incorporate this data into the LSSM. Differences in shoreline management recommendations between the fetch-based LSSM and in situ wave energy measurement-based LSSM will be quantified and analyzed. This data will be used to create a more accurate representation of the shoreline and improve living shoreline recommendations.

Coastal wetlands are essential for protecting shorelines from erosion, rising sea levels, and storms while also improving water quality and providing habitats for wildlife. In the northern Gulf of Mexico, these wetlands face significant threats from accelerated sea level rise, stronger storms, and ongoing erosion, leading to substantial land loss. This study aimed to determine the optimal depth of sediment addition, known as thin layer placement (TLP), to support the survival of Juncus roemerianus (Black Needle Rush) in this vulnerable region. Over nine months, 84 experimental units were monitored in a controlled pool environment that simulated Gulf tidal conditions, with two phases: Phase I allowing plant establishment and Phase II testing their response to different TLP depths. Results showed that Juncus roemerianus could tolerate sediment additions up to 8 inches, with these plants showing recovery and continued growth. However, at sediment depths of 10 inches or more, the plants experienced significant stress, leading to decline, with the 14-inch TLP depth causing complete burial and no recovery. In contrast, control units and those with 6-inch TLP exhibited the best performance, with high survival rates and strong growth in both shoots and roots. These findings provide crucial insights for coastal restoration efforts, suggesting that sediment additions should not exceed 8 inches to maintain healthy plant growth. This knowledge can guide more effective and sustainable shoreline restoration, extending the life of living shorelines and offering a cost-effective alternative to expensive hard structures, ultimately ensuring better protection for coastal communities.