The Najafgarh drain or Najafgarh nalah (nalah in Hindi means rivulet or storm water drain), which also acts as Najafgarh drain bird sanctuary, is another name for the northernmost end of River Sahibi, which continues its flow through Delhi, where it is channelized, and then flows into the Yamuna. Within Delhi, due to its channelization for flood control purposes, it is now erroneously called "Najafgarh drain" or "Najafgarh nullah." It gets this name from the once famous and huge Najafgarh Jheel (lake) near the town of Najafgarh in southwest Delhi and within urbanized Delhi. It is the Indian capital’s most polluted water body due to direct inflow of untreated sewage from surrounding populated areas. A January 2005 report by the Central Pollution Control Board classifies this drain, with 13