Delhi runs out of space to dispose of tons of contaminated drain silt
Delhi is facing a major ecological challenge as the city runs out of space to dispose of tons of drain silt extracted during pre-monsoon desilting operations at sites like ITO and the Najafgarh drain. Officials from the Irrigation and Flood Control (I&FC) Department warned that traditional disposal sites have reached saturation, leaving massive quantities of waste-mixed silt with no conventional means of disposal.
The search for alternative disposal methods comes amid an intensified pre-monsoon desilting drive across the Capital. According to official figures, the I&FC department removed 30.91 lakh metric tonnes (MT) of silt from major and supplementary drains this year, up from around 19 lakh MT last year.
Meanwhile, the Public Works Department (PWD) reported that it has completed desilting of 1,900.15 km of drains out of a total network of 2,125.87 km, achieving nearly 90 percent of its target. From the Najafgarh drain alone, which represents the largest single component of the desilting operations, workers cleared 12.7 lakh MT of silt.
The disposal challenge is particularly acute because the dredged material poses contamination risks to the surrounding areas. The I&FC department manages 77 drains, including 22 that empty into the Yamuna river. Nearly 25 of these are mixed-flow drains carrying both stormwater and sewage. The department removed approximately 3.5 lakh MT of silt from these mixed-flow drains, which is heavily contaminated with municipal garbage and other pollutants, making handling and reuse highly complex.
In the past, authorities disposed of silt by strengthening embankments, filling low-lying areas, depositing it at landfill sites, or allowing contractors to lift it for reuse. However, officials stated that these conventional practices have reached a saturation point and are no longer environmentally sustainable.
To resolve the crisis, the I&FC department has invited Expressions of Interest (EOIs) from agencies specializing in legacy waste management, bio-mining, and bioremediation. These agencies will develop scientific methodologies for the handling, processing, disposal, and utilization of the extracted silt. The initiative will also assess the physical and chemical characteristics of the dredged material to ensure compliance with environmental standards set by the Central Pollution Control Board (CPCB), Delhi Pollution Control Committee (DPCC), and the National Green Tribunal (NGT).
