In India, there is a selection of filtration and separation technologies that can be productively applied to resolve many of the water issues.
Links:
[1] http://admin.indiaenvironmentportal.org.in/feature-article/filtration-technologies-options-and-opportunities
[2] http://admin.indiaenvironmentportal.org.in/category/author/tom-tschanz
[3] http://admin.indiaenvironmentportal.org.in/category/journal/everything-about-water
[4] http://admin.indiaenvironmentportal.org.in/category/thesaurus/water-treatment-technology
[5] http://admin.indiaenvironmentportal.org.in/category/thesaurus/water-supply