RETARDATION OF FLOOD AND IMPROVEMENT OF FLOOD PASSING CAPABILITY OF CHENAL ARE THE NECESSARY CONSTRAIS TO LIMIT THE SENDIMENT DEPOSITID AT AN ESTUARIES OF RIVERS IN THE MIDDLE REGION OF VIETNAM

Abstract

The Central region, a long- narrow stretch of country, is one of the areas which have been permanently devastated by such natural disasters as successive typhoons, violent floods and those with solid silt leading to river mouth alluvial swamps. Several of the immediate measures to limit the damage caused by natural disasters are: 1. Stopping the uptake deforestation with a view to controlling generated sweeping floods. It also means restoring the bio- surface strata, reducing erosion as well as solid silt, and thus limiting the alluvial capacity of river mouths. 2. There are many localities with “horizotal” river mouths which, under the multi-facet influence of high tide-violent typhoon- and heavy flood complex, are in danger of river- mouth alluvion. It is, therefore, necessary to periodically clear the waterways, to enhance the capacity to carry thin silt of the water, reducing river- mouth alluvion.