September 13, 2025: The Brihanmumbai Municipal Corporation (BMC) has submitted a Rs 12,705 crore proposal to the National Disaster Management Authority (NDMA) to tackle Mumbai’s recurring flood problems. The plan includes 26 interventions designed to strengthen the city’s drainage infrastructure and improve its resilience to climate change.
Of these, 22 are structural measures such as constructing sponge parks, bioswales, permeable pavements, sluice gates, and pumping stations. For instance, a sponge park worth ₹200 crore and a bioswale costing ₹100 crore have been proposed to naturally absorb and filter stormwater. Sluice gates, with an allocation of ₹2,000 crore, are expected to regulate water flow during high tides.
Explaining the approach, a senior civic officer said, “Slow rainfall creates maximum percolation, but high rainfall doesn’t allow smooth percolation of water because the surface of Mumbai has become so impervious with time that the accumulated rainwater that doesn’t percolate gets accumulated on the surface and creates waterlogging. Therefore, our target is to increase Mumbai’s percolation capacity.”
Another official added, “Creation of bioswales and sponge parks is a cost-effective measure. Once they become operational, the percolation capacity of Mumbai’s surface will increase. Even if we can increase the percolation by 10 per cent, then it will reduce the overall waterlogging in Mumbai by a significant margin.”
Four non-structural interventions have also been included, such as an early flood warning and a cloudburst monitoring system costing ₹300 crore. “The idea behind setting up such a facility is to have an advanced warning system equipped with sensors,” an officer said.
The NDMA has sought clarifications before forwarding the proposal to the Ministry of Home Affairs. “The first step of implementing this project is to carry out an overall hydrological study of Mumbai,” a civic officer explained. Expert institutions like IIT and VJTI will assist in this process.
Source: The Indian Express
