Gurugram, Aug. 3 -- Nearly 85% of houses and half of residential societies in Gurugram have non-functional rainwater harvesting (RWH) systems, a draft drainage plan by the Gurugram Metropolitan Development Authority (GMDA) has revealed. The findings come as GMDA prepares to revamp the district's drainage system to mitigate recurring monsoon flooding. A senior GMDA official said the authority recently held its first meeting to review the plan and that more discussions are expected. "We will work on the basis of this report and ensure that rainwater harvesting structures are made functional," the official said. The report notes: "Existing recharge wells constructed by individuals in respective plots, by RWAs in common areas, and in public buildings and group housing societies need to be made functional with proper storage capacities for at least one hour and desilting chambers." It found that 85% of recharge pits in individual houses and 50% of those in group housing societies are currently defunct. The plan identifies built-up, vacant, road-covered, and green areas across Gurugram and calculates rainfall runoff in each drainage catchment. "A substantial amount of water can be saved by effectively using RWH systems inside homes and condominiums," the official added, noting that up to 50% of rainwater can be redirected to RWH units, green belts, and ponds if recommendations are followed. For Leg 1 drain (Nathupur to Najafgarh via Palam Vihar), the catchment is 6,599 acres. "Almost 70% of RWH systems in residential areas are not functional," the official confirmed. Some water diversion to green belts has been achieved in the Aravalli area above Golf Course Road. Leg 2 (Chakkarpur to Millennium City Centre) has a 15,457-acre catchment. Leg 3 (Badshahpur drain) is the largest, at 49,302 acres. Officials said enforcement of RWH norms may be strengthened, and 40% of green belts could be regraded to retain rainwater. Increasing pond capacity is also under consideration. RWH compliance is mandatory in plots over 100 sq yards, and installation reports must be submitted to Haryana Shahari Vikas Pradhikaran (HSVP) or the district town planner for possession, officials added....