Evolving Fishing Harbour Layout Using Mathematical Models

Fisheries sector is a powerful sector for employment generation as it stimulates growth for a number of subsidiary industries, most importantly it is the source of livelihood for a large population in India. A fishing harbour, intended to provide better landing and berthing facilities to fishing craft requires feasibility studies that consist of Hydrodynamics, sediment transport, Shore line changes and Wave tranquility studies. Wave propagation studies play a very important role in deciding the orientation and length of the breakwater in fishing harbour layout. The Mathematical model study is one of the tools to help in finalizing the most suitable harbour layout for inventive and cost-effective solution. The present paper describes a case study for the proposed development of a fishing harbour at Thrikkunnapuzha, Alappuzha district in Kerala state for finalization of layout from wave tranquility considerations using mathematical model techniques. Two-dimensional mathematical model MIKE-21 SW has been used for the wave climate transformation from offshore region to near-shore region. The model provides the Incident wave conditions in the near-shore region, which are likely to affect the harbour basin area. MIKE-21 BW model has been used for wave propagation in the near shore region and inside the fishing harbour basin. Based on the findings of MIKE-21 BW model simulations which are carried out for four different fishing harbour layouts for the incident wave direction from SSE, South, SSW, SW, WSW, West and WNW, the predicted safe berthing operation in terms of number of days in a year are found out. It is observed that there are appreciable differences in the layouts with concern of hydraulic aspects such as permissible wave height in the harbour basin. Based on the minimum non-operational days, easy manoeuvring of boats and other coastal phenomena like tidal hydrodynamics and littoral drift, etc., suitable layout is suggested. Thus it can be stated that for assessing the wave tranquility, mathematical model is the reliable technique for determining the fishing harbour layout.