Line 4 (Chennai Metro)

In 2013, E. Sreedharan emphasized the need for a greater expansion of the 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 received approval 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 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 also been published by CMRL.

Chennai: As many as 19 elevated metro stations may connect Poonamallee in the city with the new greenfield airport planned in Parandur. On Thursday(4.01.24), Chennai Metro Rail Limited (CMRL) submitted the detailed feasibility report (DFR) to state government, recommending an elevated metrorail corridor between the two places via Thirumazhisai and Sriperumbdur over 43.63km, construction of which may cost ₹10,712 crore. The line will be an extension of phase-2 corridor from Lighthouse to Poonamallee covering 26.1km.A CMRL official said metro trains will take passengers inside the terminals at Parandur airport, proposed to be built over 4,500 acres. Passengers may also be able reach the airport quicker as there will only a few stations located every 5km or more between Poonamallee and Parandur.Some of the major locations the metro network is likely to connect with stations include Poonamallee, Nazarathpet Police Checkpost, Chembarambakkam, Thirumazhisai township, Pappanchathiram, Chettipedu, Thandalam, Sipcot Irungattukottai, Pennalur, Sriperumbudur, Pattunool Chatram, Irungulam Industrial Area, Mambakkam, Thirumangalam, Sunguvarchatram, Santhavelur, Pillai Chattiram, Neervalur, and Parandur airport.“For the first 4km or 5km, we may have stations for every one kilometre. The total number of stations may reduce when we prepare the detailed project report,” said a CMRL official. “Once government approves the DFR, we will float tender and appoint an agent to prepare the DPR which may take around six months to get ready,” he said.A release said CMRL recommended metrorail connectivity considering the proposed new airport at Parandur, proposed bus terminus at Thirumazhisai and future growth potential along the corridor.Earlier, during the course of the feasibility study, it was assessed that there was a need for multiple stations in Parandur itself before the line terminates at the new airport because the government is planning to develop an aero city comprising a township with hotels, educational institutions, aviation ancillary units, an MRO (maintenance, repair and overhaul) hub for aircraft.The government had earlier announced a line from Poonamallee Bypass to Sriperumbudur as an extension of phase-2 corridor-4 from Lighthouse to Poonamallee Bypass (26.1km). Parandur was added after the location of the second airport was announced in August 2022 .^[7]

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]).^[8]

v t e Chennai Metro
Legend
Phase II (Line 4)
Lighthouse Kutchery Road Thirumayilai  Purple Line  Alwarpet Bharathidasan Road Boat Club Nandanam  Blue Line  Panagal Park Kodambakkam railway station Kodambakkam Power House Vadapalani  Green Line  Saligramam Saligramam Ware House Alwarthiru Nagar  Red Line  Valasaravakkam  Red Line  Karambakkam  Red Line  Alapakkam Junction  Red Line  Porur Junction Porur Bypass Thelliyaragaram Iyyapanthangal Kattupakkam Kumananchavadi Karayanchavadi Mullaithottam Poonamallee Poonamallee Bypass Poonamallee Depot Nazarathpet Chembarambakkam Thirumazhisai Pappanchatiram Chettipedu Thandalam Irungattukottai Sipcot Pennalur Sriperumbudur Pattunool Chatram Irungulam Industrial Estate Mambakkam Sunguvarchatiram Santhavelur Pillaichatiram Neervalur Parandur