what remedies were most effective in slowing down the erosion of the beach? What are the drawbacks to those remedies?

Ways to prevent beach erosion : Groyne, Offshore breakwater structure, Artificial headland. Disadvantages of each have been given below

Explanation:

Beach Erosion is of sand around coasts, it displaced to some other places.It can lead to flooding, building loss.

Ways to prevent beach erosion are :

1. Groyne  : A coastal structure - of wood, rock, bamboo - constructed perpendicular to the coastline from the shore into the,  sea to trap longshore sediment transport or control longshore currents.

Disadvantages : Erosion downdrift risk, more structure & more maintenance needed, Local scours at structures' toes

2. An offshore breakwater structure : is built in the near shore zone, parallel to the shore and serves as a wave absorber. It helps reducing wave energy by serving as a wave absorber.  

Disadvantages : Large, difficult to build & design structures, vulnerable to strong wave action

3. Aritificial Headland : It is a structure constructed to promote natural beaches, as it plays role of a artificial headland. It is relatively easy to construct and little maintenance is required

Disadvantages : Relatively large structure, Poor stability against large waves

The density of water is 1 g/cm cubed and in order for the pebble to sink its density has to be greater than the density of water and in order for the twig to float its density has to be less than the density of water

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