GHMC has the power to demolish encroachments; demand to demolish all buildings on lake beds.
Links:
[1] http://admin.indiaenvironmentportal.org.in/news/aftermath-hyderabad-floods-experts-tell-ghmc-keep-demolitions
[2] http://admin.indiaenvironmentportal.org.in/category/newspaper/deccan-chronicle-telangana
[3] http://admin.indiaenvironmentportal.org.in/category/thesaurus/telangana
[4] http://admin.indiaenvironmentportal.org.in/category/thesaurus/hyderabad-d
[5] http://admin.indiaenvironmentportal.org.in/category/thesaurus/floods
[6] http://admin.indiaenvironmentportal.org.in/category/thesaurus/land-encroachments
[7] http://admin.indiaenvironmentportal.org.in/category/thesaurus/jawaharlal-nehru-national-urban-renewal-mission-jnnurm
[8] http://admin.indiaenvironmentportal.org.in/category/thesaurus/rainfall
[9] http://admin.indiaenvironmentportal.org.in/category/thesaurus/water-resources
[10] http://admin.indiaenvironmentportal.org.in/category/thesaurus/natural-disasters