On the orders of Lieutenant Governor T.S. Sandhu, the Delhi Development Authority (DDA) has conducted a specialized operation to remove over 10,000 metric tons of accumulated silt and waste from a major underground trunk outfall drain in Rohini. This endeavor is expected to enhance stormwater flow, mitigate waterlogging, and bolster drainage infrastructure in Rohini and its neighboring areas. The project targeted a 4.095 km-long trunk drain comprising three to five parallel pipes with a diameter of 2200 mm and a total underground pipe length of approximately 16.50 km, featuring 75 inspection chambers.
The underground pipelines in the drain had been significantly obstructed over time due to continuous wastewater flow and heavy silt deposition, leading to a reduction in their carrying capacity. Traditional desilting methods were ineffective due to the confined nature and large diameter of the pipelines. To address this issue, the DDA utilized high-capacity Super Sucker and Jetting Machines. The process involved high-pressure water jetting to loosen compacted silt, which was then extracted using powerful vacuum suction equipment. The operation was meticulously carried out in a planned and phased manner with strict adherence to safety protocols.
The primary goal of this initiative was to restore the drainage network’s carrying capacity, ensuring smooth stormwater flow during the monsoon season and minimizing the risk of waterlogging in the region. The trunk drain serves as a conduit for water and discharge from Sectors-20, 21, 22, and 23 of Rohini, as well as portions of Kirari and Begumpur, making it a crucial drainage pathway in the area. The DDA has already completed desilting activities in the East, South, and North Zones, with final stages of work underway in the Narela, Rohini, and Dwarka Zones. Delhi was divided into six operational zones – East, South, North, Narela, Rohini, and Dwarka – to facilitate efficient implementation, enabling focused planning, close supervision, and timely execution of the projects.
This year’s desilting efforts have showcased the DDA’s increased capacity and improved planning, with more than 57,000 metric tons of silt already removed compared to around 33,380 metric tons removed during the previous year’s pre-monsoon drive.
