Mumbai's ₹13,000-crore flood plan: How it will become a 'Sponge City'

Maharashtra Chief Minister Devendra Fadnavis announced a Rs 13,000-crore master plan for integrated flood mitigation during the assembly session on Wednesday, incorporating traditional methods of drainage improvement along with measures based on natural elements aimed at solving the chronic flooding issue in Mumbai, particularly in the low-lying regions of the city.

According to a senior official of the BMC, the proposal has been submitted to central government officials and National Disaster Management Authority (NDMA) officials who have given their in-principle approval and a detailed project report is currently being prepared after having discussions with NDMA officials.

The flood mitigation plan is on par with the Rs 13,984 crore Coastal Road project and the funding will be as follows – 40% through National Disaster Response Fund, 30% from Maharashtra government and 30% by the BMC.


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The blueprint has been in the making for over a year now as the first NDMA meeting took place on March 12, 2025, and it was followed by site inspections and then a presentation by Union Home Minister Amit Shah after which in-principle clearance was obtained.

additional municipal commissioner Abhijit Bangar said, "The plan proposes a mix of engineering and ecological interventions, with exact locations to be finalised through the DPR. Key measures include upgrading storm-water drains to handle rainfall exceeding 55 mm per hour in vulnerable stretches and at locations where multiple nullahs discharge into a single drain, expanding pumping capacity in flood-prone areas such as Mahul and Mogra, and taking up the next phase of the Mithi river improvement project. Nature-based interventions include detention-infiltration tanks, bio-retention parks, sponge parks and permeable pavements to reduce surface runoff and improve groundwater recharge."

The project is not limited by standard flood-control methods and introduces nature-oriented methods aimed at decreasing water runoff and increasing groundwater supply. According to officials, permeable pavements will be introduced, which can absorb 12-15% of the rainwater and thus prevent its accumulation in flat areas. In addition to that, this method will be beneficial for the trees planted in the vicinity of the roads. Pipes installed underground known as detention-infiltration tanks will store rainwater for some time until it permeates the soil. The project also takes into account the problem arising from plastic waste accumulating in the drainage system. As officials say, the use of interception systems and longitudinal nets is likely to prevent trash floating on the surface from blocking stormwater channels.

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While authorities assert there is no magic solution to flood elimination, they point out that targeted measures with the assistance of scientific modeling and modernization of drainage systems can considerably reduce the amount of flooding taking place in Mumbai.