Coastal Hydrodynamic Changes Due to Large-Scale Port Development: A Case Study of the Andaman Coast, Ranong Province

Abstract

The Andaman Sea in Ranong Province serves as a major maritime gateway for Thailand, connecting trade routes with foreign countries. However, the development of a large-scale port could impact the surrounding coastal areas. This study aims to analyze the coastal hydrodynamic conditions before and after the port development using a two-dimensional mathematical model applied to the Andaman Sea area in Mueang Ranong and Kapoe Districts. The results indicate that water levels remain similar both before and after the project during the Southwest and Northeast monsoons (-0.3 to 1.1 m MSL), while in the transitional period, they range from 0.0 to 1.12 m MSL. During the Southwest monsoon, post-project current speeds (0.0 to 1.12 m/s) are lower than pre-project speeds (0.08 to 1.20 m/s). In contrast, during the Northeast monsoon, post-project current speeds (-0.1 to 1.3 m/s) are comparable to pre-project speeds (-0.2 to 1.2 m/s). In the transitional season, both pre- and post-project current speeds remain unchanged (-0.1 to 1.3 m/s). The highest current speed is observed between Ko Phayam and the port, whereas the lowest occurs between Laem Phai and the port. Furthermore, the flow direction remains unchanged between pre- and post-project conditions. These findings can inform coastal management planning for port development projects that may affect local fishing routes in the area.