Is a Living Shoreline the answer to Coastal erosion and Coastal flooding?

Living shorelines are a nature-based solution that can help combat coastal flooding, rising sea levels, and shoreline erosion. However, what exactly is a living shoreline? It uses native marsh vegetation to control erosion (Mitchell & Bilkovic, 2019). It typically involves grading, adding fill, and constructing an offshore structure made of unconsolidated rock, natural fiber logs, or created oyster reefs to reduce wave energy (Liu et al., 2019). It is an example of biomimicry and green infrastructure. However, it is important to note that gray infrastructure (such as seawalls, bulkheads, levees, and rock revetments) can negatively impact the natural migration of organisms across intertidal landscapes and affect hydrodynamic and sediment transport processes (Mitchell & Bilkovic, 2019).

Many coastal areas in the US, including Maryland, Massachusetts, New Jersey, New York, Virginia, and Florida, use living shorelines to combat erosion (Safak et al., 2020). Living shorelines also have regenerative properties that can adapt to moderate changes in coastal topography (Safak et al., 2020). However, there are some challenges in restoring salt marsh grasses, mangrove trees, and reef-building oysters in urbanized estuaries due to frequent vessel traffic and altered energy climates (Liu et al., 2019). Wetland plants and reef-building species require low-energy conditions to thrive, which can be challenging to achieve in these environments.

While a living shoreline can benefit coastal ecology and help prevent shoreline erosion, experts need more confidence in gray infrastructure to prevent erosion and flooding of coastal lands. Scientific literature reviews indicate that hard infrastructure is vulnerable to high-energy waves and has durability and maintenance cost issues in the long term. Therefore, coupling green and gray infrastructure can help take advantage of both types of coastal infrastructure. Green infrastructure, such as living shorelines, can aid nutrient retention and habitat enhancement, while hard infrastructure cannot. However, gray and green infrastructure will be required to combat climate change and protect coastal ecosystems worldwide.

Furthermore, a hybrid living shoreline called gabions and groins has been developed to address these challenges (Liu et al., 2019). This design comprises brush-filled breakwalls and the use of gray infrastructure in urbanized areas (Liu et al., 2019). Coastal erosion and flooding are becoming more frequent and dangerous due to rising sea levels caused by global warming and climate change. Experts agree (Liu et al. (2019); Safak et al. (2020); Mitchell & Bilkovic (2019); and Myszewski & Alber (2016)) that climate change has altered weather patterns, increasing hydrodynamic stress and high wave energy eroding coastal shorelines. Large and small sea vessels also affect wave attenuation and energy, contributing to the shoreline's topography changes (Safak et al., 2020).

To this end, coastal areas in the United States are experiencing shoreline erosion and flooding due to climate change, endangering communities and infrastructure. The rising sea level is causing shoreline erosion and coastal flooding, making marshes more susceptible to storms. It is a consensus that living shorelines will have a crucial role in flood control, maintaining water quality, sequestering carbon and nutrients, and providing habitats for fish, shellfish, and wildlife. Further, living shorelines will aid in combating erosion by using marsh plants to improve ecological function. LS are environmentally friendly solutions and are considered effective in enhancing coastal resilience and protecting communities from the effects of rising sea levels.

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