Speed limit determination of fishing boats in confined water based on ship generated waves

Ship generated waves (SGW) can cause bank erosion, disturbance to moored boats and bad impact on the environment especially in confined water. One of the important vessel parameters that will affect the SGW is the speed of the boat. The speed limit determination for fishing boats in confined water will be discussed which can be used as a reference to decide the maximum boat or ship speed. The confined water of Mersing River has been chosen for the current study. This river is a busy river located in Johor in the southeast area of Peninsular Malaysia. The limited speed is needed in this river because the river is restricted to many boat activities. The typical boat particulars in Mersing River are 14.05 m in length, 4.35 m in breadth and 1 m in draft. The field experiment has been conducted with several scenarios considering the speed and tidal conditions. The results of the experiment were used to determine the maximum energy of SGW in this area. By using trendline characteristics, the formula of maximum energy was generated by considering the speed of the boat. The Brisbane River Criteria in Australian River has been selected due to the same characteristic with Mersing River. Hence, the reference for allowable energy was defined in this study. By using this river criteria, the limit of the boat speed was provided for all tidal conditions (ebbing, slack and flooding), and it was found that the allowable speed as the speed limit in the Mersing River is 5 knots. This will reduce bank erosion, disturbance to moored boats, environmental impacts and energy consumption. Moreover, the generating process of the formula can be a reference to get the speed limit at particular area as the river in other areas.