Hanamgond, P.T., 2024. Morpho-dynamics of Malvan-Devbag Beach, Maharashtra, West Coast of India. In: Phillips, M.R.; Al-Naemi, S., and Duarte, C.M. (eds.), Coastlines under Global Change: Proceedings from the International Coastal Symposium (ICS) 2024 (Doha, Qatar). Journal of Coastal Research, Special Issue No. 113, pp. 240-245. Charlotte (North Carolina), ISSN 0749-0208.

The coastal length of Maharashtra is about 720 Kms which is almost 10% of the Indian coast. The beaches here are micro-tidal (0-2 m tidal range) with semi diurnal tides. The present study area- the Malvan-Devbag beach stretching about 15km, is a barrier beach along the south Konkan coast region of Maharashtra state. The coastal region here is hilly, narrow highly dissected with transverse ridges of the Western Ghats, and at many places extending as promontories into Arabian Sea. The shoreline is very irregular, associated with features like cliffs, notches, promontories, sea caves, embayments, submerged shoals and offshore islands. The morpho-dynamics at 7 locations, on monthly, seasonal and annual scale during June 2008 to July 2010 indicated dominating erosion during May/June (approach of monsoon) and reach the peak during monsoon (July/August). The beach starts regaining during September and develops fully by May with well-developed berm(s). The algebraic sum of volume change showed overall gain. It is observed that the longshore currents (both northerly and southerly) occur in the range of 0.2 - 1.0 m/sec; and majority of the currents are in the range of 0.2-0.4 at all the locations with the predominance of northerly currents. Sediment samples were collected across all the locations at 10m interval. The sediment size varies between medium to very fine, majority being fine, well sorted to moderately sorted. In general, the sediments of the study area are deposited under moderate to high-energy turbulence conditions. The CM patterns indicate moderate to high energy conditions of deposition. The sediment movement paths differ between station to station. In general, the alongshore sediment paths show northerly sediment transport during all the seasons. The cross-shore sediment movement shows cyclic behavior i.e., during monsoon it shows offshore transport and during fair-weather it shows onshore transport. This corroborates the general trend of West Coast beaches and supports the growth of the beach during the fair-weather season.