Explainer: Why Mumbai’s Monsoons Turn Into Water Woes

Mumbai: Once again images and videos of roads, railway tracks and even underground metro facing floods due to heavy rain in monsoon is getting viral all over social media again.

#WATCH | Maharashtra: Bhosari area of Pimpri-Chinchwad of Pune district waterlogged, following heavy rainfall here. pic.twitter.com/9wt5B5GmZn

— ANI (@ANI) June 13, 2025

But who is responsible for the monsoon mess?

Across many parts of India, the monsoon has transformed the landscape into a lush, vibrant haven, and people are reveling in the refreshing embrace of rain, enjoying the cool breezes and the rhythmic dance of droplets. Yet, in the heart of the nation’s financial hub, Mumbai, the picture is quite different. As the city’s streets turn into overflowing streams and traffic snarls become more chaotic, thousands of residents find themselves caught in the frustration of relentless flooding and waterlogged roads. While the monsoon smiles kindly elsewhere, Mumbai’s residents battle the storm’s chaos, navigating the streets with patience and hope that the rains will soon ease, bringing relief rather than inconvenience.

The Brihanmumbai Municipal Corporation (BMC) springs into action, installing de-watering pumps in flood-prone areas and manually clearing waste from drains to prevent waterlogging. Despite these efforts, many residents find that it’s too little, too late. Streets that should be free-flowing become flooded battlegrounds, and neighborhoods are submerged in frustration and helplessness. The city’s struggles highlight a harsh reality—despite years of warnings and attempts at mitigation, the impact of heavy rains continues to disrupt life in Mumbai.

This recurring crisis is not unique to Mumbai.

Across India, the story repeats itself each monsoon season, stretching from Delhi in the north to Bengaluru in the south. Roads collapse under the weight of water, drains overflow, and infrastructure buckles under the relentless pressure. Traffic snarls into chaos, halting movement and complicating daily routines for millions.

Each city faces its own battles with nature’s fury, exposing vulnerable urban systems that are overwhelmed every year.

Experts point to the root causes behind this persistent problem: rapid, unplanned urbanization, crumbling infrastructure, and decades of environmental neglect.

These issues have created a perfect storm, leaving cities ill-prepared for the deluge of monsoon rains. Without sustainable and strategic planning, the cycle of flooding, destruction, and frustration will continue, underscoring the urgent need for holistic urban development that can withstand nature’s seasonal tests. Ultimately, these floods are more than just weather events—they are a wake-up call for India’s cities to build resilience and adapt for the future.

Which Factors Lead to Chaos?

A combination of natural factors, outdated infrastructure, unplanned urban growth, and poor governance.

1. Very Heavy Rainfall:
   During the monsoon, which lasts from June to September, Mumbai gets more than 200 mm of rain on average. However, this rain doesn’t fall evenly over the months. Instead, it often comes in sudden, heavy bursts. These quick, intense showers put a lot of pressure on both surface and underground drains, causing water to pond on roads and flood parts of the city.
2. Old and Overcrowded Drainage System:
   Mumbai’s drainage system was built over 100 years ago during British rule. It was designed to handle only 25 mm of rain per hour, which is much less than what the city now receives. A project called BRIMSTOWAD was started about 20 years ago to fix this, especially after a big flood in 2005 that caused many deaths. But the work is still not finished, mostly because of illegal land encroachments and legal issues.
3. Fast City Growth:
   Mumbai has grown very quickly without enough planning. Places like wetlands, open spaces, and mangroves that used to absorb floodwaters have been taken over for buildings and roads. Rivers like the Mithi, which used to carry extra rainwater out to sea, are now narrowed, polluted, and clogged with debris. Buildings made of concrete reduce the ground’s ability to absorb rain, causing more water to flow into the drains.
4. Location and Tides:
   Since Mumbai is on the coast, its drainage network empties into the Arabian Sea. During high tide, especially when it matches heavy rains, seawater blocks the drainage, causing water to back up into the city. During low tide, water drains more easily, but high tide often leads to flooding.
5. Waste in Drains:
   Lots of trash, especially plastic and construction waste, ends up in drains and open sewers. Even moderate rain can clog these drains, causing water to pond and traffic jams in already crowded areas.
6. Climate Change:
   Climate change makes monsoons unpredictable and more extreme. Mumbai now faces sudden, very heavy rainfall instead of steady showers. Rising sea levels also cause higher tides, making flooding worse.
7. Poor Planning and Coordination:
   Different government agencies like BMC, MMRDA, and others work separately, which slows down important projects. Better planning and early warning systems could help keep people safe and reduce flooding. But currently, there is a lack of coordination, making it difficult to fix the problems quickly.