The Sagar Island,located north of the Bay of Bengal,intercepts the flow in the Hoogly estuary that comprises a network of several estuarine distributaries and creeks,which is considered to be one of the largest estuar...The Sagar Island,located north of the Bay of Bengal,intercepts the flow in the Hoogly estuary that comprises a network of several estuarine distributaries and creeks,which is considered to be one of the largest estuarine systems in the world.The Hooghly River experiences a tidal range in the order of about 4 m,due to which the tide-generated currents drive the sediments which are continuously set in motion.The temple,Kapil Muni(21°38'15.35"N,88°4'30.56"E)is located on the south-western side of Sagar Island,where an annual religious festival and rituals with about a million pilgrims is conducted.The pertinent erosion problem at a rate of about 5 m/year is prevalent at the site has considerably reduced the beach width,thereby,resulting in reduced space for religious as well as recreational activities along the coast.A novel cross-section for the proposed submerged reef using geosynthetic materials is designed considering the different sitespecific,environmental,and socio-economic conditions.The submerged reef can effectively be devised to redistribute the current circulation pattern and trap the sediment for beach restoration.The performance of such a structure depends on its geometrical and structural characteristics,the location of the reef(i.e.)the water depth at the toe,distance from the coastline,wave-structure interaction,sediment transport and local morpho dynamics.The aforesaid criteria were optimized using a numerical model which predicted the average residual velocity in the site to be in the order of about 1 m/s.Owing to logistical constraints geosynthetic materials had to be employed.The detailed design of such a system arrived through numerical modelling and field measurements are presented and discussed in this paper.展开更多
文摘The Sagar Island,located north of the Bay of Bengal,intercepts the flow in the Hoogly estuary that comprises a network of several estuarine distributaries and creeks,which is considered to be one of the largest estuarine systems in the world.The Hooghly River experiences a tidal range in the order of about 4 m,due to which the tide-generated currents drive the sediments which are continuously set in motion.The temple,Kapil Muni(21°38'15.35"N,88°4'30.56"E)is located on the south-western side of Sagar Island,where an annual religious festival and rituals with about a million pilgrims is conducted.The pertinent erosion problem at a rate of about 5 m/year is prevalent at the site has considerably reduced the beach width,thereby,resulting in reduced space for religious as well as recreational activities along the coast.A novel cross-section for the proposed submerged reef using geosynthetic materials is designed considering the different sitespecific,environmental,and socio-economic conditions.The submerged reef can effectively be devised to redistribute the current circulation pattern and trap the sediment for beach restoration.The performance of such a structure depends on its geometrical and structural characteristics,the location of the reef(i.e.)the water depth at the toe,distance from the coastline,wave-structure interaction,sediment transport and local morpho dynamics.The aforesaid criteria were optimized using a numerical model which predicted the average residual velocity in the site to be in the order of about 1 m/s.Owing to logistical constraints geosynthetic materials had to be employed.The detailed design of such a system arrived through numerical modelling and field measurements are presented and discussed in this paper.
