Circulation & sedimentation processes in and around the Aguada bar

Abstract

An attempt is made to gain some insight into the complex processes of the estuarine and bay circulation and sediment transport and deposition responsible for the formation and maintenance of the Aguada bar - a navigational hazard near the mouth of the Mandovi estuary. A schematic pattern of water circulation in the bay and the estuary entrance is arrived at through studies on the float trajectories and the sediment distribution in and around the bar. It is suggested that the higher wave activity and the large volume’ of sediment laden river discharge during the south-west monsoon result in truncation of the bar followed by a general shallowing of the surrounding region. The flow pattern for the fair weather season suggests a gradual building up of the bar through 2 circular cells of water movement in the bay near the mouth of the estuary. The interaction of refracted and diffracted waves with the flood and ebb currents, over the shoals, is also discussed.