## 2 Materials and Methods
### Sampling and Data Collection  
Sampling procedures were conducted using topographic, bathymetric, and metocean measurement methods. Bathymetric measurements were carried out to acquire data on the seabed surface profiles, employing a Single Beam Echo Sounder, an instrument utilizing sound waves for reflection off the water bottom [32,33]. The bathymetric survey was divided into three distinct areas, as depicted in Figure 4. This survey specifically targeted areas along the coastline that suffered severe erosion and locations frequented by ships, rather than covering the entire coastal region. Area-1, which encompasses the outermost zone measuring 1500 m \(\times\) 930 m, featured survey lanes set at intervals of 100 m \(\times\) 100 m. Moving to Area-2, which covered the outer region near the shoreline, it spanned a total area of 543,300 m\({}^{2}\). In this area, the survey lanes were designed with a 10 m spacing along the main lane perpendicular to the shoreline and a 20 m spacing along lanes intersecting the main lane. Area-3 consisted of the bay/pool area with dimensions of 171 m \(\times\) 156 m, and its lanes were configured with a 10 m spacing along the main lane perpendicular to the shoreline and a 20 m spacing along lanes intersecting the main lane. The survey findings for these three areas provided seabed depth data. In Area-1, the seabed depth ranged from 3.55 m to 14 m below the Low Water Spring (LWS). Area-2 showed seabed depths ranging from 0 to 4.75 m below the LWS, while in Area-3, depths ranged from 5.25 m to 9.75 m below the LWS. The maximum seabed depth was recorded at the jetty head in Area-3, measuring 8.95 m below the LWS. Table 1 presents the data pattern of the bathymetric measurement coordinates for each area. In Area-1 and Area-3, 4 boundary points were utilized, whereas Area-2 had a total of 11 boundary points, owing to the survey's adherence to the coastline's shape in that area. Figure 3: Condition of exposed pipeline installations in the Port Area. On the other side, the metocean method was performed to obtain tide, wind, wave, and current data at Pulau Baai Port. The wave and current observation survey employed an Acoustic Doppler Current Profiling (ADCP) instrument, with data collected at hourly intervals for 17 min over a period of 30 days. ADCPs employ the Doppler shift in echoes from pulsed signals within directed acoustic diverging beams to estimate flow velocities, making them suitable for deployment in diverse environments like oceans, rivers, and estuaries for extended durations (several months) to assess flow variability across a broad spectrum of time scales, typically sampling at a few hertz [34]. Tidal observations were conducted using a Valeport Tide Master instrument over the same 30-day period. Wind \begin{table}
\begin{tabular}{c c c c} \hline
**Point Area** & **Boundary Point** & **Easting** & **Northing** \\ \hline \multirow{4}{*}{Area-1} & 1 & 197,610.10 & 9,568,924.32 \\  & 2 & 198,699.66 & 9,569,885.73 \\  & 3 & 199,379.46 & 9,569,251.95 \\  & 4 & 198,204.89 & 9,568,207.89 \\ \hline \multirow{4}{*}{Area-2} & 1 & 198,392.11 & 9,568,323.29 \\  & 2 & 198,505.32 & 9,568,304.53 \\  & 3 & 198,757.12 & 9,568,449.05 \\  & 4 & 198,866.37 & 9,568,481.43 \\  & 5 & 198,892.78 & 9,568,373.67 \\  & 6 & 199,008.25 & 9,568,310.85 \\  & 7 & 199,084.41 & 9,568,307.13 \\  & 8 & 199,190.73 & 9,568,354.56 \\  & 9 & 199,421.73 & 9,568,515.30 \\  & 10 & 199,744.38 & 9,568,913.65 \\  & 11 & 199,376.74 & 9,569,239.29 \\ \hline \multirow{4}{*}{Area-3} & 1 & 199,129.72 & 9,568,040.02 \\  & 2 & 199,275.90 & 9,568,104.75 \\ \cline{1-1}  & 3 & 199,347.36 & 9,567,954.81 \\ \cline{1-1}  & 4 & 199,206.58 & 9,567,886.56 \\ \hline \end{tabular}
\end{table} 
Table 1: Planned boundary coordinates for the bathymetric survey area. Figure 4: Scheme of the bathymetric survey study area locations. data samples were taken from a meteorological station installed at an elevation of 10 Mean Sea Levels (MSLs) within the study area.