Coastal Erosion
Wave action and flooding in coastal areas can wear down or carry away rocks, soils, and/or sands along the coast resulting in coastal erosion. Coastal storms that include large waves, storm surge, potentially in combination with high tides, create more damaging conditions to the coastline and any built structures that exist on the coastline. Seasonal changes occur due to late summer/fall hurricanes and winter storms. Coastal storm events often devastate barrier islands, which buffer the main coastlines from the storm energy. Rising sea levels and increasing intensity and frequency of coastal storms are making coastal erosion worse.
The videos explain how coastal erosion occurs and highlights the many ways damage is occurring to human infrastructure.
Drone video of extreme coastal erosion along Pacific Beach near San Francisco, CA.
Extreme coastal erosion along the shorelines of Lake Michigan in northern Indiana.
Great perspective on the problems and potential solutions along the coastline of South Carolina. (Watch the first few minutes for an introduction.)
Exercise 3 – Coastal Erosion
Use the resources below to answer the following questions:
- Coastal Erosion | U.S. Climate Resilience Toolkit
- Definitions of coastal terms – Coastal Wiki
- Watch the videos
- Coastal erosion is the wearing away and transportation of material away from one section of a coastline. T/F
- Coastal erosion removes material from the shoreline and redistributes it to other parts of the coastline. T/F
- Coastal erosion can also occur gradually over a long time due to sediment deficits. T/F
- Coastal erosion is reversible. T/F
- What is the main cause of erosion along a coastline?
- This feature along the coastline offers the best protection to the mainland from coastal storms.
- How do tropical storms impact coastal erosion?
- What is the estimated value of property loss each year due to coastal erosion in the US?
- These two coastlines of the US are experiencing the highest coastal recession.
Coastal Engineering
Coastline erosion around the world, particularly in large cities, is often at considerable risk due to coastal erosion. The erosion is often mitigated using a combination of coastal structures that can arrest the loss of sediment, redirect wave energy, or redirect the flow of sediment along coastlines.
Exercise 4 – Coastal Engineering
Use the resources below to answer the following questions:
- Coastal Protection and Mitigation | Coastal Processes, Hazards, and Society (psu.edu)
- beachnourishment.wcu.edu
- Watch the videos
- What are the two types of strategies used to reduce or stop erosion along coastlines?
- These erosion mitigation strategies are cost-effective in the long run. T/F
- These erosion mitigation strategies help reduce coastal erosion permanently. T/F
- Identify the different methods below that represent hard mitigation strategies.
- Identify the different methods below that represent soft mitigation strategies.
Coastal Protection Using Hard Structures (psu.edu) shows different types of hard structures. Use Google Earth to navigate to the geographical locations shown below (Latitude (N) and Longitude (W)) and identify the different coastal erosion and protection structures in the area.
- 32.7692852 -79.9288478
- 32.7304813 -79.8359377
- 32.6787736 -79.8941089
- 32.686272 -79.8863391
- 25.7629516 -80.1274675
- 25.8053492 -80.1225144
Now navigate to Folly Beach County park at this link on Google Earth, and answer the following questions:
- What type of coastal structure is installed here?
- Which side of this structure is accumulating sediment?
- Which side of this structure is losing sediment?
- Based on the gain and loss of sediment next to the structure, what is the direction of longshore drift?
Using beach nourishment data for South Carolina, answer the following questions:
- Move your mouse cursor on the map and identify which coast of the US has the highest beach nourishment episodes.
- Move your mouse cursor on the map and identify which US state has the highest beach nourishment episodes.
- How many different episodes of beach nourishment have occurred in SC?
- What is the approximate cost (in 2020 cost) of all these beach nourishments (round off to the nearest million)?
- What is the approximate cost (in 2020 cost) of Folly Beach nourishments (round off to the nearest million)?
- What is the primary funding source for these beach nourishment projects?
- Explain if this source of funding may be reasonable. Give one each of Pro and Con rationale.
- Consult the US Climate Resilience Kit and list two non-structural solutions to stabilizing coastlines such as Folly Beach.
