The Mithi River bed lies 9.57 meters above the railway line. The structure travels through layers of brecciated basalt rock and slush beneath the river’s flow.
According to Mumbai Metro Aqua Line 3, train service has started on the Dharavi to Acharya Atre Chowk segment, with trains traveling to Kotak BKC Metro station.
According to One India, this 9.77-kilometer section, which has six stations, should be prepared for commercial operations by March 2025, pending safety inspections and certifications.
According to a project official, testing runs up to Acharya Atre Chowk have been successfully finished. Social media users also posted a video of the trial runs that featured the stations. Phase 2A includes this development. By the end of 2025, the last section, which stretches to Colaba, should be finished. The trip from JVLR to Acharya Atre Chowk will take around 39 minutes once it is fully operational.
Significant obstacles were encountered during the project, especially when building beneath the Mithi River. There were no prior examples to follow, and this was the first attempt at such work in this kind of soil.
Between the Bandra Kurla Complex (BKC) and Dharavi stations, there is a twin-tunnel stretch of the railway line that runs beneath the river. The New Australian Tunnelling Method was applied, and successive excavation was carried out using tunnel boring machines (TBMs) called Godavari 3 and Godavari 4.
The 3-kilometer twin tunnel segment passes beneath an enlarged body of water for about 2 kilometers, including 500 meters below the Mithi River, which is currently active. Custom-made earth balance devices were employed to address these issues by preventing ground settlement, controlling water seepage, and guaranteeing stability.
A unique gasket system was created for this location to stop water intrusion. Watertightness is ensured by mushroom-type gaskets found in precast concrete segment rings. Furthermore, a layer of hydrophilic gaskets improves the joints’ waterproof integrity by expanding when exposed to water.
Dharavi station, located next to Kotak BKC station, is positioned 18 to 18.5 metres underground. The six stations on this stretch are:
- Dharavi
- Sitaladevi
- Dadar
- Siddhivinayak
- Worli
- Acharya Atre Chowk
