Two drinking water lakes of Hyderabad - Osman Sagar and Mir Alam, were studied for their chemistry for two years (1977-78). Mir Alam, the older of the two, showed higher silicate content. Dissolved component formed 91-27% of the total silicate content in these lakes.
Links:
[1] http://admin.indiaenvironmentportal.org.in/feature-article/chemistry-two-freshwater-lakes-hyderabad-india-silicates
[2] http://admin.indiaenvironmentportal.org.in/category/author/k-satya-mohan
[3] http://admin.indiaenvironmentportal.org.in/category/journal/pollution-research
[4] http://admin.indiaenvironmentportal.org.in/category/thesaurus/water-pollution
[5] http://admin.indiaenvironmentportal.org.in/category/thesaurus/lake-pollution
[6] http://admin.indiaenvironmentportal.org.in/category/thesaurus/lakes
[7] http://admin.indiaenvironmentportal.org.in/category/thesaurus/osmansagar
[8] http://admin.indiaenvironmentportal.org.in/category/thesaurus/water-quality
[9] http://admin.indiaenvironmentportal.org.in/category/thesaurus/andhra-pradesh
[10] http://admin.indiaenvironmentportal.org.in/category/thesaurus/hyderabad-d