Sea Defences
Pantai Morib has 3 major sea defences: mangroves, a sea wall and a revetment. We only looked at the sea wall and revetment in close detail. Below are the 3 sea defences with annotations, along with a detailed analysis of the functions and uses such as: posotive/negative aspects of each, the effectiveness, appearance, problems and sustainability.
Concrete Revetment
- As you can see in figure 1, the first sea defence we observed was the reinforced revetment directly in front of a hotel, on the beach (it is also adjacent to the promenade).
- Square blocks are made out of concrete and tesselate to create a reinforced revetment. Concrete is quite strong but isn't the best material to beat erosion.
- It takes form as a gentle slope to lessen the power and forces of the waves, and allows the water to flow back to sea. This is due to the fact the wall goes with the motion of the wave.
- The concrete blocks have holes in them, which weaken the waves and drain away some of the water, so that the wave runs up and then down the concrete.
- There is also a short, vertical concrete wall with a angled edge at the top of the revetment to reflect the wave's destructive power back to the sea if there is a very high tide or in a stormy weather.
Figure 1: Concrete Revetment directly in front of hotel.
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Sea Wall
- As you can see in figure 2, the second defence we observed was a sea wall along the sides of the promenade, which protects the restaurants and recreational facilities behind it. how sustainable?
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Figure 2: Sea wall at the promenade.
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Mangroves
- Even though this was not one of the sea defense we were focusing on, mangroves are an excellent natural sea defense.
- Mangroves are crossroads where ocean, freshwater, and land realms meet. Mangroves act as a natural sea defence.
- They help protect the coast agaisnt natural hazzards such as: storms, tsunamis and coastal erosion.
- They reduce: wave impact, storm surges, floods, tsunamis and lessens damage by absorbing wave energy.
- The dense roots of manroves help build soils. Above ground roots slow down water flows, encouraging deposition of sediments and reduce erosion.
- Build up of soils, increase thickness of soil, which maybe critical as sea level rises.
Sketch Map of Pantai Morib (Bird's Eye View)
Figure 3: Sketch map of Pantai Morib from a bird's eye view.