It is not only just the Ulsoor Lake which is polluted.
Links:
[1] http://admin.indiaenvironmentportal.org.in/news/35-citys-lakes-are-highly-polluted-finds-kspcb-study
[2] http://admin.indiaenvironmentportal.org.in/category/author/bosky-khanna
[3] http://admin.indiaenvironmentportal.org.in/category/newspaper/deccan-herald-bangalore
[4] http://admin.indiaenvironmentportal.org.in/category/thesaurus/karnataka
[5] http://admin.indiaenvironmentportal.org.in/category/thesaurus/lake-pollution
[6] http://admin.indiaenvironmentportal.org.in/category/thesaurus/state-pollution-control-board-spcb-0
[7] http://admin.indiaenvironmentportal.org.in/category/thesaurus/bangalore-t
[8] http://admin.indiaenvironmentportal.org.in/category/thesaurus/drinking-water
[9] http://admin.indiaenvironmentportal.org.in/category/thesaurus/irrigation
[10] http://admin.indiaenvironmentportal.org.in/category/thesaurus/water-pollution