Chennai: Metro commuters can expect shorter waits and less crowding on peak-hour trains by 2028, as Chennai Metro Rail Limited (CMRL) plans to induct 28 new six-car trains on its phase I network. This will reduce train frequency to three minutes on corridor one (Airport-Wimco Nagar) and 4–5 minutes on corridor two (Chennai Central-St Thomas Mount), replacing the current arrangement where trains run every 6 to 12 minutes on some sections and often operate as short-loop services — such as between Washermenpet and Alandur — rather than covering the full stretch.CMRL’s 54km phase I has seen rising ridership, pushing current infrastructure to its limits. “Anticipating a surge in demand following commissioning of phase II by 2026-27 and the extension of corridor one to Kilambakkam, CMRL is upgrading its fleet and operations,” said T Archunan, director (projects), CMRL.By 2028, corridor one is expected to carry up to 13,900 passengers an hour in a direction, while corridor two may take about 5,600 during peak hours. To manage this, CMRL will transition to a combined fleet of 80 trains by 2028 — 52 existing four-car sets and 28 new six-car sets.To support six-car operations, infrastructure upgrades are planned at 21 underground stations. Nineteen of these require electrical integration for Platform Screen Doors (PSDs) — glass doors on platforms that open only when trains arrive — and some need full platform extensions and fresh PSD installations. Elevated stations such as those at Guindy, Alandur, Airport, and CMBT will also receive new PSDs, as per tender documents. These retrofits are being planned to meet 2036 demand in one phase, avoiding repeat work later.Depots too are being scaled up. The Koyambedu and Wimco Nagar depots will see new stabling lines, upgraded washing plants, inspection bays, and MP (machinery and plant) capacity to handle the expanded fleet.Commuters say it’s high time CMRL added more trains — 2028 already feels too late. “During morning peak hours, it’s so crowded near the doors that boarding or getting off is a struggle, and it can get risky. Bags or clothes sometimes get caught in the automatic doors,” said D Ramakrishnan, a resident-activist from Adambakkam.