The Sahibi or Sabi River originates in Jaipur District of the state of Rajasthan. After passing through Alwar District in Rajasthan and Gurgaon District in the state of Haryana it enters Delhi near Dhansa.
In the earlier years, the discharges in Sahibi used to moderate till the same reached Delhi. Due to interception of Jahajgarh and other jheels and the under ground reservoirs of Rajasthan and Haryana,very little quantity of water used to enter Delhi. Due to land developments and improvement in Drainage system in Haryana, it is seen that every year, the quantity of water entering Delhi increased and the Najafgarh Jheel areas started remaining under water for the full year. To check this entry of water in Delhi, the bund and regulator at dhansa were constructed in the Year 1964 and the same year there had been an unprecedented heavy flood in Sahibi which caused breach in Dhansa Bund and resulted in submergence of most of areas of Najafgarh Block in deep waters.
Instances of heavy flood in Sahibi have been in the years 1967 and 1977. Though the flood of 1967 did not make any damage in Delhi area but 1977 flood created even worse position than 1964, when even the far off colonies of Delhi like Janakpuri, etc. were threatened by the flood waters.





This is now the famous najafgarh drain which is the 60% cause of all pollution in river yamuna.