Most of the water for Bangalore is imported by BWSSB from the Cauvery River, which is over 100 kilometers south of the city. The water is drawn from a reservoir near the village of Thorekadanahalli. To meet the increasing demand, the "Cauvery Water Supply Scheme" was undertaken by BWSSB in three stages to supply 540 MLD of water.
Links:
[1] http://admin.indiaenvironmentportal.org.in/feature-article/energy-audit-bwssb-bangalore
[2] http://admin.indiaenvironmentportal.org.in/category/journal/active-conservation-techniques
[3] http://admin.indiaenvironmentportal.org.in/category/thesaurus/cauvery
[4] http://admin.indiaenvironmentportal.org.in/category/thesaurus/urban-water-supply
[5] http://admin.indiaenvironmentportal.org.in/category/thesaurus/energy-efficiency
[6] http://admin.indiaenvironmentportal.org.in/category/thesaurus/energy
[7] http://admin.indiaenvironmentportal.org.in/category/thesaurus/bangalore-t