Chennai Metro Rail Limited (CMRL) will begin tunnelling from Kolathur station to Srinivasa Nagar in the second week of December, as part of Phase II Corridor 5. The 1,000-metre stretch was scheduled to start in September but was delayed after residents protested the proposed underground construction and CMRL changed the work sequence. The first tunnel boring machine is expected to reach Srinivasa Nagar by July 2026; the second is expected a couple of weeks later. Tunnelling is estimated to take about seven months. The first 600 metres comprise decomposed rock interbedded with clay, followed by 400 metres of grade IV rock strata. The preceding stage, from Kolathur ramp to Kolathur station, began in February and had covered 246 metres by August. Corridor 5 runs 47 km from Madhavaram to Sholinganallur and includes a 5.8-km underground section. It is the longest corridor in Phase II, whose network spans 118.9 km. Retteri, Kolathur, Srinivasa Nagar and Villivakkam are on Corridor 5.

Two pits left uncovered after underground drainage repairs in Ward 24, Srinivasa Nagar, on Vayalur Road, are endangering pedestrians and motorists. Corporation workers dug three pits last week to fix sewage leaks but covered only one. In the past two days, two motorists fell into the open pits and were injured, and three vehicles were damaged. The pits contain stagnant water, causing a foul smell and attracting mosquitoes. Residents also report that streetlights have been non-functional for over a month and say repeated complaints have brought no action. Ward 24 Councillor Shopiya Vimala Rani said she would instruct workers to cover the pits immediately and resolve the streetlight problem by Tuesday.

Puzhal is one of five lakes providing drinking water to Chennai. Sewage from Ambattur, 13 km away, enters the lake because several areas in the zone lack underground sewage network (UGD). Underground drainage work was promised to commence October 2025 but has not started. Sewage from stormwater drains enters a rainwater canal along Manal Odai Road that was built to carry floodwater to Puzhal lake from Lenin Nagar, Saraswathy Nagar, Padmavathy Srinivasa Nagar and others. About 450 families either discharge sewage into stormwater drains or use lorries. Metro Water had planned to construct the underground sewage system and water supply network in left-out areas and streets through the Ambattur area office, but the board later changed the decision to implement through headquarters. A detailed project report has been prepared for the network in left-out areas.

Chennai Metro Rail Limited has commenced Phase II expansion with three corridors totalling 118.9 km, funded by Asian Development Bank, Japan International Cooperation Agency, New Development Bank, and Asian Infrastructure Investment Bank.

Corridor 5 runs 47 km from Madhavaram Milk Colony to Sholinganallur, passing through Koyambedu, Porur, and Alandur. It comprises five underground and 39 elevated stations. The 7.8 km underground section with twin 3.9 km tunnels from Kolathur Ramp to Nathamuni Ramp includes five underground stations, executed by Tata Projects Limited.

Four tunnel boring machines (TBMs) named Kurinji, Mullai, Marutham, and Neithal will be deployed. TBM Kurinji was launched first, boring 246 meters from Kolathur Ramp to Kolathur Station (upline), expected to complete in June 2025, then be relaunched 1.06 km towards Srinivasa Nagar. TBM Mullai will arrive by end of March 2025 and bore 603 meters adjacent to Villivakkam Railway Station towards Villivakkam Bus Terminus. Remaining TBMs will launch based on site readiness.