The Tamil Nadu government has granted administrative sanction for the preparatory work on the 21.76-km Koyambedu–Avadi–Pattabiram metro corridor. This approval allows Chennai Metro Rail Limited (CMRL) to begin land acquisition, utility shifting, and other groundwork while awaiting clearance from the Union government.The State government had already approved the project in May and submitted the detailed project report to the Centre. However, the Ministry of Housing and Urban Affairs has also requested a Comprehensive Mobility Plan (CMP) before granting final approval.According to an order issued on 18 August by the Department of Planning, Development and Special Initiatives, CMRL can commence initial activities along the Outer Ring Road alignment. The corridor, fully elevated, will include 19 stations, such as Padi Pudhu Nagar, Golden Flat Junction, Ambattur Estate, Ambattur Station, Ambattur OT, Thirumullaivoyal, Avadi Railway Station, Pattabiram, and Outer Ring Road.The total project cost is estimated at Rs 99.28 billion, of which Rs 24.42 billion has been sanctioned for preparatory work. This funding, provided by the State government as subordinate debt, will cover expenses such as land acquisition, surveys, and utility relocations. Around Rs 1.88 billion will be dedicated to topographic surveys, geotechnical investigations, tree replantation, and traffic management.Residents of Avadi have urged the State to expedite the submission of the CMP to the Centre. Local resident T. Sadagopan stated that thousands commuting from central Chennai to Avadi, Ambattur, and Pattabiram would benefit significantly from faster connectivity, adding that the region’s many Central government institutions also underline the urgency of approval.The new corridor is expected to ease traffic, improve accessibility, and extend metro services to some of Chennai’s most densely populated suburbs.