INDORE (Metro Rail News): Indore Metro has entered a new phase of metro construction with TBM Narmada starting the city’s first underground tunnelling work. The machine will dig the tunnel from Airport Station towards the Bada Ganpati area. The tunnel will run nearly 20 metres below the ground.
Indore Metro has started its first underground tunnelling operation with the launch of TBM Narmada from Airport Station. The development marks the first time a tunnel boring machine has been deployed for underground metro construction in the city.
According to a TOI report, Madhya Pradesh Metro Rail Corporation Limited (MPMRCL) managing director S Krishna Chaitanya said safety, construction quality and technical standards must remain the priority throughout the tunnelling work.
Indore Metro begins underground tunnelling with TBM Narmada
Narmada will construct the underground tunnel from Airport Station of Indore Metro towards the Bada Ganpati area. The machine will operate at a depth of around 20 metres below the surface. The TBM uses Earth Pressure Balance (EPB) Mix Shield technology. As it moves forward, the machine excavates the soil and installs precast concrete segments to form the tunnel lining.
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The technology is designed to support controlled excavation in underground conditions while maintaining the stability of the tunnel as the machine advances. Key specifications of TBM Narmada include:
- Cutting wheel diameter: 6.65 metres
- Total machine length: About 102 metres
- Technology: Earth Pressure Balance (EPB) Mix Shield
- Launch point: Airport Station
- Tunnelling depth: Nearly 20 metres
Machine tested in Thailand before arriving in Indore
The TBM completed its Factory Acceptance Test (FAT) in Thailand on April 25, 2026. It was then transported to Indore, where engineers assembled the machine at the launch site. After assembly and preparations, Narmada was launched from Airport Station to begin the underground drive.
The machine will install precast concrete rings as it progresses. These segments will form the permanent lining of the tunnel behind the cutting head. The underground operation will use several systems to monitor the TBM and the surrounding construction environment. Officials said the tunnelling system includes:
- Continuous monitoring from a control room
- Gas detection and monitoring
- An emergency stop system that can halt the machine within one second
- Precise control of the TBM along the approved tunnel alignment
- Precast concrete ring installation as tunnelling progresses
The focus on monitoring will be particularly important as the machine moves beneath the built-up parts of the city.
A new phase for Indore Metro
The launch of Narmada takes Indore Metro construction beyond elevated viaduct work and into underground construction for the first time.
The Airport-Bada Ganpati tunnel will require the TBM to maintain its planned alignment while operating deep below the surface. The progress of this drive will therefore be an important construction milestone for the city’s underground metro network.
Also Read: Indore Metro Launches First TBM ‘Narmada’ for Underground Construction