<P> For restoring the minimum environmental flows, it is difficult to identify nearly 100 Tmcft storage reservoirs in the hilly region of Ganga basin in India as the river is flowing through steep valleys . Already big storage reservoirs like Tehri and Ramganga are constructed at feasible locations . However the water of Manasarovar Lake located in China can be diverted to the upstream of Kanpur barrage (117 m msl) via Girijapur Barrage (129 m msl) located at 28 ° 16 ′ 21" N 81 ° 05 ′ 09" E ﻿ / ﻿ 28.27250 ° N 81.08583 ° E ﻿ / 28.27250; 81.08583 across the Ghaghara / Karnali river which is a tributary of Ganga river flowing from Tibet / China and Nepal . </P> <P> Manasarovar Lake's surface area is 320 square kilometres (120 sq mi) and its maximum depth is 90 m (300 ft). It holds more than 100 tmcft water in its top 13 meters depth . At present it is overflowing into nearby Lake Rakshastal which is a land locked salt water endorheic lake . The annual water inflows from the catchment area of Manasarovar lake located at 4,590 metres (15,060 ft) above msl, can be diverted by gravity to the Karnali River basin of China through a 15 - kilometre long tunnel . </P> <P> The diverted water available continuously can be used in China for hydroelectric power generation where the head drop available is in excess of 800 meters over a 40 km long stretch . This would be a joint project of China, Nepal and India for controlling river water pollution and making the Ganga river live and flowing throughout the year . With the diversion of Manasarovar lake water to Ganga basin, Lake Rakshastal would turn into a Soda lake with further increase in water salinity which is useful in abstracting the water - soluble chemicals on commercial scale . </P> <P> The fresh water inflows into Manasarovar lake can be augmented further substantially by gravity diversion of the inflows available from the major catchment area of Rakshastal lake to Manasarovar lake by constructing an earth dam isolating northern tip of Rakshastal lake where it is fed by its substantial catchment area and also connected to the Manasarovar lake . </P>

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