Langsford Road Living Shoreline
The Biodiversity, Sea - Level Rise, and Living Shoreline Opportunity at the Langsford Road Marsh
What is erosion?
Erosion is the wearing away of soil, rocks, and sand, causing damage to the marsh and the species that live there. This can happen naturally, but with higher tides, erosion occurs at a much greater rate. Melting glaciers in Greenland and Iceland are causing sea-levels to rise as well, and this can also increase erosion. This issue causes the loss of land and vegetation, as well as damage to property and habitats.
Image Credit: Mae Richardson
Sea Level Rise Predictions
These sea-level rise projections are based on greenhouse gas emissions and the increased melting of ice sheets. 1.6 feet by 2100 is already set in stone for the future. However, the most likely scenario is 3.9 feet by 2100. This implies that greenhouse gas emissions will peak around 2040, and then they will start to decrease. On the other hand, if nothing is done to decrease greenhouse gas emissions, it is possible that there will be 6.1 feet of sea-level rise by 2100. These numbers demonstrate the importance of starting to reduce our greenhouse gas emissions.
(1 meter = 3.28 feet )
Hard Structures
Hard structures and living shorelines, despite their immense differences, both have some level of benefits and drawbacks. Hard structures control erosion by blocking wave energy from hitting the land, which prevents flooding. Hard structures are the best for locations that don’t have an established shoreline ecosystem, such as Kennebunk beach. Unfortunately, they’re are mostly short-term due to their lack of resilience and inability to grow and adapt to their surrounding environment. They’re mainly made out of concrete, which cracks and breaks down. Because of this, hardscapes require costly repairs every 6-15 years, depending on its size, material, and amount of wave and wind energy it’s facing. This can be seen with the recent sea wall renovation on Gooch’s Beach in Kennebunk. This demonstrates why hard structures are financially and physically ineffective in preventing erosion and guarding the essential infrastructure against sea level rise.
Image Credit: Rowan Pow
Living Shoreline
A living shoreline is also an erosion control method that stabilizes a shoreline and preserves the natural state of the ecosystem. Living shorelines are made out of natural materials that can help take carbon dioxide out of the atmosphere, if constructed with living plants. These plants stabilize the shoreline and combat sea-level rise by trapping sediment (accretion). This builds up the previously-eroding shoreline to help combat the effects of sea level rise. The natural shoreline provides habitats for native species. While these are great benefits, living shorelines can have their drawbacks as well. A limitation of living shorelines is that they can only be used in low wave energy areas, ideally a marshland, and can be expensive when first installing them. However, in the long run, they will not need repairs because they become a part of the land, which is better financially in the long run.
Image Credit: Maine Geological Survey
Citations
Interactive sea-level rise scenarios for Maine coasts.
“Climate Change: Global Sea Level: NOAA Climate.gov.” Climate Change: Global Sea Level | NOAA Climate.gov, 25 Jan. 2021
Global and Regional SLR Scenarios for the US Final - Tide
Reyes, Pia De Los. “The Impact of Coastal Erosion on Seaside Communities.” One Green Planet, One Green Planet, 7 Oct. 2021
“Living Shoreline Academy .” Module 2 - Coastal Erosion