Dirty Downstream Ganges: What Fate is Waiting?

The Hugli estuary, in the extreme western part of the lower Gangetic delta in the downstream region is a major estuary of the tropics. It is adjacent to the highly urbanized city of Kolkata, Howrah and the newly emerging Haldia port-cum-industrial complex. The selected sampling station (marked in yellow square) is 2.8 km off Sagar island (the triangular big island on the middle of the map), which is almost at the confluence of the Hugli estuary and the Bay of Bengal (Figure 1). This area has been selected as the test bed of the present study owing (i) presence of multifarious industries that are the point sources of zinc, copper and lead (ii) continuous plying of fishing vessels and trawlers that use antifouling paints for conditioning, whose main ingredients are zinc, copper and lead (non-point sources) (iii) presence of brick kilns, industries and thickly populated city of Kolkata, Howrah and the Haldia port-cum-industrial complex that serve as the primary sources of carbon dioxide at the local level and (iv) a major navigational channel in the region