Gururgram, April 24 -- The Gurugram Metropolitan Development Authority (GMDA) is set to use drone surveys to identify illegal pathways and sewage discharge points along the 26km Badshahpur drain (Leg-3), from Ghata to Sector 99 via Vatika Chowk, as part of a plan to curb pollution, remove unsafe access routes and ease pressure on the city's stormwater network, officials said on Thursday. Following complaints about informal access routes linking areas upstream of the Gadauli culvert with settlements such as Ramprastha, Behrampur and Badshahpur, the GMDA has decided to deploy drones to identify and seal unsafe pathways along the Badshahpur drain, which ultimately flows into the Najafgarh drain. Meanwhile, the Municipal Corporation of Gurugram (MCG) will act against sewage discharge points from nearby commercial establishments in Sectors 66, 67 and 69, officials said. A senior GMDA official, who did not wish to be named, said several of these unauthorised pathways double up as access points for illegal sewage connections from nearby residential colonies. "Such connections discharge sewage directly into the drain network. In many cases, concrete slabs placed on drain embankments increase the risk of overflow and pose a safety hazard," the official said. Officials added that encroachments along a 6km stretch between Dhankot and Basai on Leg-3 will be removed, after which grilles will be installed to improve safety. "An estimate for repair work along the Leg-3 drain will be prepared soon. The aerial survey will enable geo-tagged mapping of polluted stretches and help seal unsafe access points," the official added. Authorities are also planning diversions to manage overflow. In March and April, two high-level meetings were held among civic agencies to discuss measures to tap 55 million litres per day (MLD) of untreated effluent flowing into Leg-3 and the Sohna elevated road drains. "Illegal sewage connections from commercial establishments in Sectors 66, 67 and 69 are being sealed. Tenders have also been floated for desilting work and for deploying pump sets to manage wastewater in the area," an MCG official said. Officials said an internal sewer line being laid up to the Dwarka Expressway, which will be connected to the master sewer line by June 30, is expected to reduce pressure on Leg-3's stormwater channels. The MCG is also likely to divert wastewater from five under-tapped discharge points along the Gadauli culvert upstream, two near Behrampur, and one each near Ullawas and Ghata villages during this period. Officials said water quality tests of the Leg-3 drain conducted in January recorded biochemical oxygen demand (BOD) levels of 90 mg/l. Around 30 diversions of illegal discharge points are planned by June....