Section 118(5) in Kolkata Municipal Corporation Building Rules, 2009
(5)No kitchen, bathroom or water closet shall be permitted in any basement unless there is proper drainage arrangement. If permitted, such kitchen, bathroom or water closet shall be placed against an external wall of the basement, which shall also be the external wall of the building, and shall be adequately lit and ventilated. Detailed plans showing arrangements for drainage including pumping system shall be submitted in such cases.
