Longshore Drift and Groynes
How do Groynes prevent longshore drift?
TKS
By: Saksham Yadav
Longshore Drift and Groynes
Introduction
Aim:
To determine how groynes prevent longshore drift.
The issue:
Longshore drift influences the deposition and erosion of sediments. Waves erode the coast and transport the eroded material along the coastline. Over a period of time, the material will be deposited on a beach or form a larger feature such as a spit. Groynes are structures built at equal intervals along the coastline. Their purpose is to restrict longshore drift, preventing coastal erosion.
Figure 1 - Google Maps
About the location:
The location of the study area is Silver Beach in Kurnell Peninsula, near Cronulla. It is located in the Sutherland Shire, south of Sydney Central Business District (CBD) and just directly south of Kingsford Smith International Airport. The area also has a historical significance as it is near the landing place of Captain James Cook on the 28th of April 1770 in Botany Bay.
Figure 2 - Close up of the study area, Silver beach is located just on the border of Captain Cook Drive
Figure 3 - Captain Cook Monument, taken by Saksham Yadav on 25/2/14 at Botany Bay
Importance of the issue:
Longshore drift is a process by which sediments are transported from one place to another. When this process occurs, beaches, spits and sandbars are accreted over time. If the process of longshore drift is altered by factors such as stronger winds and stronger currents, beach erosion begins at a faster rate and this may result in many serious problems. The main stakeholders of longshore drift are resort owners. They rely on people to visit their resorts and enjoy the beach. However, if longshore drift erodes t...
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... consider some ideas of what can be done to further enhance the management of the coastal issue. Using the research action plan, I aim to acquire a sophisticated understanding of longshore drift, coastal management and implementations of coastal issues, through the research action plan. Most importantly, I will include various diagrams explaining how the process of longshore drift occurs and what implementations it has on coastal environments, accompanied by an explanation of how the issue is being managed, a detailed outline of the geographical processes involved and a discussion of the impacts of the issue and why it is important.
Figure 6 - How longshore drift works (Brief). Source: Classwork image (originally from Google images)
Main Findings
Accompanied by detailed insights into the issue
Geographical processes involved in longshore drift:
Bibliography
See Location Map of the coastline being studied from Herne Bay to Reculver.
Method(data collection) ----------------------- If Long Shore Drift were taking place, I would expect to find: * Deposition of pebbles on one side of any obstruction. This obstruction could be a headland or an artificial barrier such as a groyne.
Investigating the Geographical Processes that are Affecting the Physical and Built Coastal Environment There are three geographical processes that are affecting the physical and built coastal environment, they are; erosion, deposition, and transportation. Erosion is the group of natural processes, including weathering, dissolution, abrasion, corrosion, and transportation, by which material is worn away from the earth’s surface, this is mainly caused by wind, running water, and waves breaking on the coast. Deposition is the depositing something or the laying down of matter by a natural process. Transportation is when sand is moved along the coast by long shore drift. At North Cronulla beach erosion is evident.
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