New drain master plan finalised; aims to handle 3x more rainfall

NEW DELHI: After decades of delay, abandoned drafts, and monsoon chaos, Delhi has finally completed a new drainage master plan — nearly half a century after the last one was prepared in 1976, officials said.

- Snehil Sinha

The ambitious plan, finalised by the Public Works Department (PWD), seeks to build a climate-resilient, technologically advanced stormwater system that can withstand extreme rainfall, rapid urbanisation, and the Capital’s swelling population, officials added.

“The project has been developed with the help of consultants using advanced tools such as ArcGIS, SewerGEMS and SWMM. It integrates the city's drains, water bodies, wetlands and parks to optimise infrastructure and strengthen resilience,” one of the officials cited above said.

Delhi's current drainage system is built to handle just 25mm of rainfall at a time. In contrast, the new network will be capable of managing 65-70mm, officials said. While the city occasionally records extreme spells of 100mm rainfall in a day, such instances are limited to four or five days a year.

“Several days in the last two years have seen over 50 mm of rain in a short period, each exposing the city’s weaknesses.