Significance of Wave and Tide Induced Circulation in Development of a Fishery Harbour

Abstract

Waves and tide play important role in the design of a harbour layout. A fishing harbour located at Kerala Coast influenced by tidal currents and wave action due to its shape was studied using 2D mathematical model. The nearshore currents are mainly governed by action of waves. The wave induced currents in the area are mainly in southward direction along the coast. The effect of waves and tidal currents has caused sedimentation inside the harbour. The response of the harbour with respect to variation in tidal heights, currents and wave actions has been studied to optimize the port layout. In this paper, hydrodynamic circulations in the vicinity of the harbour mouth and in the harbour basin resulting due to the combined effect of waves and tides has been studied to assess sedimentation in the region. The layout, which causes minimum circulation in the vicinity of harbour area, is recommended as it is likely to cause lesser sedimentation in the region. A substantial savings in the cost of harbour layout was achieved by reducing the breakwater lengths by 620 m, which provided same effectiveness in restricting sedimentation in the harbour.