Why in news?
Mumbai received over 300 millimetres of rainfall in a single day in August 2025. The downpour caused the Mithi River to swell to almost four metres and forced the evacuation of hundreds of residents from low‑lying areas. The incident highlighted the river’s degraded condition and its role in the city’s flooding.
About the river
- The Mithi River is a seasonal stream that functions as a stormwater drain for Mumbai. It flows through the suburbs of Powai, Saki Naka, Kurla, Kalina, Vakola, the Bandra–Kurla Complex, Dharavi and Mahim.
- The river originates from the overflow of Vihar Lake and receives water from Powai Lake about two kilometres downstream. After flowing roughly 18 kilometres, it empties into the Arabian Sea at Mahim Creek.
Features and issues
- Variable width: The river is about five metres wide in its upper reaches and widens to 70 metres near Mahim after desilting following the 2005 floods.
- Pollution hotspot: The Mithi carries untreated sewage, industrial effluents and solid waste. Encroachments along the banks contribute to its poor water quality.
- Reduced flood capacity: Years of siltation and encroachment have decreased the river’s ability to carry floodwaters, increasing the risk of waterlogging during heavy rains.
Restoring the Mithi River requires improving sewage treatment, relocating encroachments and integrating riverfront development with flood‑management planning.