Impact of Mudbanks on Coastal Dynamics

Abstract Mudbanks are a major morphological feature which has a very close and direct impact on coastal dynamics. This paper is an attempt to study the impact of mudbanks on coastal dynamics. The coastal stretch of south of Alleppy coast extending from Kayamkulam inlet to Alleppy Pier is considered. Over the past so many decades this coast has been witnessing the formation, dissipation, migration and disappearance of mudbanks continuously at several locations along the coast. Local information on the appearance/disappearance of mudbanks at various locations along the coasts during the recent years has been collected and discussed. The impact of mudbanks on the coastline dynamics along selected locations of Alleppy coast has been studied through GPS shoreline mapping, satellite images and presented. The study discusses the recent mudbank occurrence along Alleppy coast against those reported in the past and their significance in coastal dynamics. It is understood that the shoreline changes and erosion/accretion process are significantly controlled by the occurrence, non-occurrence mudbanks that form along the coastal sector. If mudbanks occur constantly for a few years at a particular location beach continuously accretes and disappearance /migration of mudbanks accelerates erosion. It is also observed that the beach sediments accumulate in the mudbanks region and its north and severe erosion is found along the coastal stretch south of the mudbank. Developing a solid knowledge of this local phenomenon would benefit in positioning fishing harbours and implementing coastal protection measures effectively.