Post-Monsoon Equilibrium Beach Profiles and Longshore Sediment Transport Rates at Candolim, Miramar and Keri Beaches of Goa, India

Equilibrium profile is one of the concepts in coastal geomorphology which is a result of the balance of destructive versus constructive forces. Two equilibrium beach profile models, viz. Bruun/Dean's twothirds power model and modified Bodge exponential model were used to analyse the measured post-monsoon (winter) beach profiles from three beaches in Goa having varying coastal morphology settings. The major factors that affect the equilibrium beach profile, viz. the median grain size (D₅₀) and the profile shape factor m, which are inversely proportional to each other, have been analysed for their application to the study site. Also, the variation of these two parameters with beach slope and grain size is studied. Longshore sediment transport rates (LSTRs) are estimated at these three beaches from the littoral environmental observations. LSTRs show that during winter months, the net transport is of the order of 10.83 × 10⁶ m³/year (southerly transport) and 9.02 × 10⁶ m³/year (southerly transport) respectively, at Candolim and Keri beaches, whereas it is about 0.62 × 10⁶ m³/year (northerly transport) at Miramar. This article discusses the methods used and results of measurements of beach morphology, LSTRs, analysis of equilibrium profiles and influence of various parameters related to equilibrium profiles.