The Aqua Line 3 of the Mumbai Metro,[5] also known as Colaba-Bandra-Seepz Line, is a part of the metro system under construction in Mumbai, India.[6][7] When completed, the 33.5-km long line will be the first underground metro line in Mumbai and will be operated by MMRC.[8] The metro line will connect Cuffe Parade business district in the extreme south of the city to SEEPZ in the north-central[9] with 26 underground and one at-grade station.[10] The track width is standard gauge. The cost of this corridor is estimated at ₹30,000 crore (US$3.8 billion). Line 3 is expected to reduce road congestion, besides reducing the load on the Western Line between Bandra and Churchgate.[11][12]
The project is being implemented by the Mumbai Metro Rail Corporation Limited (MMRCL). The line starts at Cuffe Parade, will run through Nariman Point, Churchgate, CSMT, Girgaon, Worli, Dadar, Mahim, Bandra-Kurla Complex, Santacruz (East) and past the domestic and international terminals of Mumbai Airport, through Andheri MIDC and terminates at SEEPZ.[11][13] The 33.5 km, Rs. 23,136 crore project involves five major entities - MMRCL (Mumbai Metro Rail Corporation Limited), Padeco, MMRDA, CREC (China),.[14] Major (65%) funding for the project was received through a soft loan of Rs. 13,235 crore from JICA (Japan International Cooperation Agency) with the rest provided by the exchequer through the Government of India and Government of Maharashtra.[15][14][16]
The section of the line between Bandra Kurla Complex and Dharavi stations includes a 170 metre long twin-tunnel passing under the Mithi river. One of the tunnels was completed in March 2020.[17] This will be the second under-river metro rail tunnel in India after the tunnel underneath the Hooghly river on Kolkata Metro Line 2.[18]
The construction of this metro route faced hurdles from environmentalists and activists lodging numerous PILs over cutting of trees in various region accompanied with a larger protest in Aarey over the carshed construction. PILs were either dismissed or didn't succeed as both the Supreme Court and the Maharashtra High Court cited the importance of the metro project.[19][20]
An extension of the line has also been proposed to extend the line by 2.5 km to Navy Nagar from Cuffe Parade. As per the initial plan, Cuffe Parade was planned to be the first station of the line; however, after extension, the first station will be Navy Nagar. There are 26 stations planned earlier, which will be 27 stations on the line after the extension. The extension on metro line 3 will cost an additional ₹2,301 crore.[21][22]
