The length of the coastline in West Bengal is 220 km with a coastal zone [stretching from LTL to 500 m (as CRZ) inland and up to the landward extension of the successive series of older sand dune stretching up to Orissa Coast Canal in the western part; and LTL to Dampier-Hodges line, which serves as the boundary of the Sundarban Biosphere Reserve, also sensu stricto physiographically] of about 9,630 square km. The coastal zone supports an approximate population of 7 million.
Based on tidal amplitude only, West Bengal coast can be sub-divided into two different coastal environments namely (Figure 1):
1. The macro tidal (tidal range > 4 m) Hugli estuarine plain characterized by a network of creeks encompassing the islands with spectacular mangrove vegetation and off-shore linear tidal shoals from Sagar Islnd to the border of Bangladesh to the east.
2. Meso tidal (tidal range 2 – 4 m) Medinipur (Digha-Sankarpur-Junput) coastal plain to the west of the Hugli estuary with rows of sandy dunes separated by clayey tidal flats from Sagar Island to Orissa border to the west.
Figure 1: Location map of West Bengal coast. Erosional shores are outlined in blue, accretional areas in red.
This contrasting physical nature of the West Bengal is also reflected in the coastal resources east and west of Hugli estuary.