Effect of artificially dumped material on the configuration of Baina beach, Goa

Abstract

The change in beach topographic features along with variations in particle size distribution of beach sediments from Baina, at three selected stations, with special amphasis on the effects of dumping of dredged material from Mormugao harbour on the beach, have been studied. The study has revealed that at station 1, located at the dumping point of the dredged material, 70 m due to the dumping operations, and (ii) a runnel extending up to 250 m on either side of the dumped spot has formed. In general, the beach experiences cut from May to July and fill from September to March. Before dumping operations, the sediments of the beach at all the 3 stations hsd their mean grain size in medium sand class and moderately well sorted to moderately sorted with symmetrical or negatively skewed distribution. After the dumping operations, the sediments at stations 2 and 3 remain in the same class limits, whereas the samples at station 1 are in fine sand. class, poorly sorted and very negatively skewed. These flndings indicate that there is very slow littoral movement existing along the beach. Further, if any foreign material with different texural characteristics is dumped on this beach, the material is not likely to move appreciably along the beach nor does it influence the neighbour in and regions much.