Water Resource
In Sikkim, the role of water resources in the environment is paramount. It is recognized that water is a scarce and precious natural resource to be planned, developed and conserved in an integrated and environmentally sound basis. In doing so, the preservation of the quality of environment and the ecological balance are also of prime consideration. The Teesta is the major river system in the state.
Source: State of Environment Report 2007, ENVIS Sikkim
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Ratey Chu is a river in the Indian state of Sikkim that is the main source of water for the state capital, Gangtok. Ratey Chu emerges from the glacier-fed lake Tamze at an elevation of 3,800 metres (12,500 ft) above sea level. Ratey Chu is tapped for drinking water at an elevation of 2,500 metres (8,200 ft). From this tapping point or water supply head work, water is transported for 17 kilometres (11 mi) to the Selep Water Treatment Plant site.
» Water Quality of Ratey Chu (water source of Gangtok) 2007 to 2015 
» Also see: Overveiw of Ratey Chu Watershed