The Public Works Department (PWD) is likely to finalise a detailed project report for a drainage master plan for Delhi by the end of June, an official said on Wednesday.
According to the city’s current and future needs for an effective drainage system, the Delhi government has been working on a new drainage master plan since 2021.
The PWD has divided the city into three basins — Najafgarh, Barapullah, and Trans-Yamuna — and hired consultants to redesign the drainage network.
As part of the plan, these consultants have analysed factors like slopes, depressions, and the existing old and incapable infrastructure to improve drainage efficiency, he said. While desilting is handled by multiple civic bodies, the PWD maintains 2,064 km of storm water drains along all the main roads, covering almost 55 per cent of the city’s entire drain length of 3,740.31 km. The PWD is the nodal agency on drainage in the city.
Delhi’s last drainage master plan was prepared in 1976 when the population of the city was just 60 lakh. According to rough estimates, the population has now gone up to around two crore.
In 2023, 308 water logging hotspots were identified by the traffic police due to several factors like unprecedented rainfall; and lack of proper drainage which led to backflow of water and stagnation at these locations.
“After the DPR is approved by the government, the agency starts the process of inviting tenders from private companies to carry out the work on the ground,” the officer said.
The original drainage master plan was prepared by IIT-Delhi in 2018 which largely identified that rapid unplanned urbanisation, shallow groundwater level and low elevation are some of the major reasons resulting in frequent flooding problems in the city.
However, this report was rejected by the previous government as “generic” in nature and a fresh master plan preparation process was commenced.
Last year, the Delhi High Court suggested that only a single agency should be involved in the management of storm water drains in the city. Earlier, the IIT-Delhi report had identified the involvement of multiple departments in drain management as a problem.
In 2023, unprecedented rainfall caused flooding, with the Yamuna River reaching a record-high flood level of 208.66 metres, surpassing the previous record from 1978. This caused widespread flooding, further highlighting the urgency of improving the city’s flood management systems. As part of pre-monsoon preparations, the PWD has already started desilting work of drains in a phase-wise manner.
