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Figure 5.5 Overview of a regional bathymetry that includes the proposed site between Tg. Kapal and Tg.Ayam. The study area is highlighted.

5.1.2.2 Waves

The study area is located in the southern stretch of the state of Johor facing the Strait of

Singapore in an area with limited fetch that does not allow the generation of significantwaves by local winds. Most wave energy reaching the site propagates from the South East

China Sea and, similar to the wind conditions, waves are affected by the monsoon

conditions.

Wave modelling was carried out in the study area and results are presented in Figure 5.6

and Figure 5.7 for NE and SW monsoon conditions respectively. It can be observed during

NE monsoon conditions that waves are predominantly travelling from the NE. However,

Tg. Penyusop and the Ramunia sand banks (on the southern end of the east facing

shoreline) tend to impose some of energy dissipation as the waves tend to refract and also

break. In spite of these energy losses, it is observed that some wave energy is able to reach

the study area during these monsoon events.

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Figure 5.6 Predicted wave field during NE monsoon conditions as predicted by the wave model.

During SW monsoon conditions waves travel from the SE but the exposure of the coastline

during these events is limited due to the sheltering effect introduced by the islands

(especially Bintan Island) to the south east end of the Strait of Singapore as shown in

Figure 5.7.

Figure 5.7 Predicted wave field during SW monsoon conditions as predicted by the wave model

Due to the conditions of the area as described for both NE and SW monsoon periods,

waves propagate from the South East China Sea and following the natural coastline tend to

refract due to the counter of seabed and rotate and re-orientate so that they reach the site

from the east-south east. A wave rose based on model results south of the study area is

presented in Figure 5.8, which clearly illustrates that most wave energy occurs from the E-

SE direction. These wave conditions are extracted on the offshore area south of the study

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Independent Deepwater Terminal at Pengerang, Johor Chapter 5

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site. In the shallow nearshore areas waves will further reduce and rotate due to refraction

and wave breaking. As it can be observed typical wave heights do not exceed 1 m.

Figure 5.8 Computed wave rose south of the study area.

5.1.2.3 Water Levels and Currents

The area offshore the proposed site is located in the Strait of Singapore that connects the

South East China Sea (SECS) with the Malacca Straits. These two water bodies tend to

observe different tidal conditions with diurnal pattern (one tidal peak and low a day) in the

SECS and semidiurnal on the Malacca Strait. As a result, the study area is in a transition

zone that observes a mixed tidal pattern. Measured water levels just offshore the sites are

presented in Figure 5.9.