CHENNAI: In a few years, metro rail commuters would only need a mobile app and a smartcard to seamlessly switch between different modes of local transport as metro rail’s interchange stations will link metro, MRTS, suburban rail and MTC depots at 28 different locations in the city and the suburbs. These stations are coming up in the 118.9km phase-2.People will be able to plan their commute well ahead through the app, which will have information on the routes, modes of transport, timetable and duration of commute. Commuters will be able to move from metro stations to bus depots to MRTS stations through exclusive walkways, skywalks or subways.A metro rail official said these stations are being designed to run one above the other in the elevated corridors to minimise land acquisition. In case of underground interchanges, a smaller station packing all the commuter facilities will come up closer to the existing underground stations. These stations will be linked either through long winding subways underground or skywalks in the elevated corridors. Wherever metros would link bus services , the station entry points are designed to lead commuters directly to the depots and terminuses.“The interchanges are being designed in such a way that commuters would be automatically directed to other modes of transport whether it is MTC or MRTS or suburban. In most of these stations, they would not step out to the main road,” an official said. Construction for phase-2 is likely to begin early 2020 and a 52km stretch is expected to be ready by 2024-25.In phase-2, the stations have been planned in such a way that it would make commuting to the suburbs easier. There will be 11 interchange stations linking MRTS, suburban and MTC between Madhavaram and Sholinganallur. Commuters at Perambur and Chetpet suburban stations or Greenways Road and Thiruvanmiyur MRTS or MTC depots at Aynavaram, Mandaveli or Adyar could easily board a metro train, as stations will be built nearby.A smaller station has been planned on the road opposite Kilpauk Medical College near the existing underground station. These stations would be linked through subway. But stations like Thirumangalam, which is underground now, will be linked to a new smaller elevated station on 100 Feet Road through a ramp or a skywalk. Alandur will have another corridor and a station at 40m height and will be connected through skywalks or walkways.The corridor between Lighthouse and Poonamallee will have interchanges at Nandanam and Vadapalani, which are already connected through metro rail. For instance, Nandanam is along Anna Salai line while in phase-2, a new station will be on a line that goes from west to east. “At Nandanam, we may have a pedestrian subway to link the two underground stations,” an official said.Similarly, commuters boarding metro trains in Madhavaram could switch between two metro stations at Thirumangalam to proceed to airport or to Central.There will be interchanges in suburbs like Alwarthirunagar, Valsaravakkam, Karambakkam, Alapakkam, Porur and Poonamallee as they have high passenger traffic but not public transport facility.