Line 4 (Chennai Metro)

E. Sreedharan, in 2013, stressed on the need of a greater expansion of Chennai metro network by undertaking subsequent phases. In July 2016, the then Chief Minister J. Jayalalithaa announced that Chennai Metro Phase 2 would be 104 km long and have 104 stations.[1] In July 2017, in a suo motu statement in the State Legislative Assembly, an extension in Phase II, involving an extension of Line 4 from Lighthouse up to Poonamallee, with the Madhavaram–Sholinganallur and Lighthouse–Poonamallee lines intersecting at Alwarthirunagar was announced, making Phase 2 116.1 km long.[2] The key focus for Phase 2 is to connect the northern (Madhavaram, Redhills) and southern parts (Siruseri, Sholinganallur) and the east parts of Chennai (Light house, Mylapore) to the western parts of Chennai (Porur, Poonamallee).

The present estimate for the phase 2 stands at Rs. 63,000 crore and approval received from the state government. Foundation stone for phase 2 was laid on 20 November 2020 by Union Home Minister Amit Shah and construction for the phase from Poonamallee to Power House of Line 4 commenced on 1 June 2021.[4][5]  Addressing an event in Chennai, Prime Minister Narendra Modi on Sunday 14 February 2021 said the Centre has set aside Rs 63,000 crore in this year’s Budget for the second phase of Chennai Metro totaling 116.1 km, which is one of the largest projects sanctioned for any city in one-go.[6] The map and list of stations for all 3 lines of Phase 2 has been published by CMRL.

Feasibility study to extend the Phase 2 by 93 km undergoing. DPR for 15.3 km Blue line 1 extension pending approval from the state government. [7] [8] Phase 2 is expected to be completed by 2028.[9] Phase 2 will have 138 trains with three coaches, making a total of 414 coaches.[10]

The stations in phase II will be smaller at 300 m (980 ft) compared with 220 m (720 ft) in phase I. Phase II will have three depots, namely, Madhavaram (30 hectares), SIPCOT (10 ha [25 acres]), and Poonamallee (20 ha [49 acres]).[11]