The Indian Green Building Council has asked the Hyderabad Metropolitan Water Supply and Sewerage Board to restore blocked rainwater-harvesting pits across the erstwhile GHMC area to arrest the falling groundwater table. Hyderabad: Indian Green Building Council (IGBC) has urged the Hyderabad Metropolitan Water Supply and Sewerage Board (HMWSSB) to revive defunct rainwater-harvesting pits to tackle Hyderabad’s declining groundwater table. At a roundtable meeting here on Friday, IGBC national chairman C.