The Chennai Metro Rail (CMRL) system requires multiple depots to stable, maintain, and overhaul its train fleet. The main depots are built as part of the system's different phases.
 

Project Description

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The depots are complex industrial facilities crucial for the entire metro network's operational efficiency and longevity. Key depots in the CMRL project include:

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1. Koyambedu Depot (Phase I): This was the first operational depot for the network, covering approximately 25 hectares. It serves the trains running on the Phase I corridors (Blue Line and Green Line).

2. Wimco Nagar Depot (Phase I Extension): An elevated depot designed to support the northern extension of the Blue Line up to Wimco Nagar.

3. Madhavaram Depot (Phase II): Slated to be the largest facility (approx. 27.8 hectares), this depot will be the main maintenance and stabling hub for trains on Phase II Corridors 3 (Madhavaram to SIPCOT) and 5 (Madhavaram to Sholinganallur). It is designed to handle over 100 trains, including the new driverless rolling stock.

4. Poonamallee Depot (Phase II): A planned depot to serve the trains operating on Phase II Corridor 4 (Lighthouse to Poonamallee Bypass).
    

Scope of a Typical Metro Depot: A depot is far more than just a parking area; it is a full-service rail complex that includes:

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• Stabling Lines: Tracks for parking trains overnight or between operational periods.

• Inspection/Maintenance Sheds: Heavy-duty buildings with inspection pits, elevated tracks, and overhead cranes for routine checks and minor repairs.

• Workshops: Dedicated buildings for major overhauls, wheel profiling, bogie repair, and component maintenance.

• Washing Plant: Automated train wash facilities.

• Administrative & Ancillary Buildings: Control rooms, offices, crew rest facilities, substations, and pump houses.

• Test Track: A dedicated track for testing trains after major maintenance.

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Scope of Involvement for JG Building Group

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JG Building Group played a key role in the development of the Chennai Metro Rail Depot by delivering comprehensive civil, structural, and infrastructure works to support large-scale urban transit operations. The scope of work was executed in alignment with Chennai Metro Rail Limited (CMRL) standards, ensuring safety, durability, and long-term operational efficiency.

Key Scope Areas:

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• Civil & Structural Construction:
  Construction of depot buildings, maintenance sheds, inspection bays, stabling lines, workshops, and administrative facilities.

• Rail Infrastructure Works:
  Development of internal rail tracks, ballastless track foundations, drainage systems, and alignment works within the depot premises.

• Maintenance & Workshop Facilities:
  Execution of specialized structures for train maintenance, washing plants, underfloor wheel lathes, and equipment housing units.

• Utility & Services Infrastructure:
  Installation of underground utilities including water supply networks, sewerage systems, stormwater drainage, and cable duct corridors.

• MEP Coordination Support:
  Civil interface and coordination support for electrical substations, power distribution rooms, signalling rooms, and telecom infrastructure.

• Roads & External Development:
  Construction of internal roads, parking areas, boundary walls, security checkpoints, landscaping, and site circulation planning.

• Safety & Compliance Management:
  Implementation of strict safety protocols, quality assurance systems, and compliance with metro rail construction regulations and environmental norms.
   

Project Outcome:
 

The depot was delivered as a robust, future-ready facility capable of supporting high-frequency metro operations, preventive maintenance, and fleet expansion, contributing significantly to Chennai’s urban mobility infrastructure.