Kolkata will soon have an underground Metro under the river Hooghly
Kolkata will soon have an underground Metro which will pass through tunnels many feet under the Hooghly.
• Tunnel dug 30 metre underground
• Depth of water in Ganga here is 5.13 metre
• Total distance between impervious layer and river is 13 metres
• Total length of track is 16.6 km
• Automatic train with no driver. Can be driven remotely too
• Type of track is ballastless
• Underground track is 10.8 km
• Alignment issues sorted in 2015
• Type of gauge is standard gauge 1,435
• Will connect Howrah and Sealdah — the busiest railway terminals in West Bengal
• Number of tunnels is two
• Six air-conditioned coaches in each train
• Number of passengers per train will be around 1,000
The first transportation tunnel of India is ready and the second will soon be completed.
A transportation tunnel is unique to India because never in the history of the country has a tunnel been made beneath a flowing river.
The tunnel has been made 30 metres under the river, just a few metres away from the famous Howrah Bridge, built last century to connect Howrah and Kolkata.
There are not even roads under a river in India but this is a technological marvel, where trains will chug out of the platform every two and a half minutes.
‘It will be connecting two main terminals: Howrah and Sealdah — each of which has a footfall of about 10-12 lakh passengers per day,’ said Satish Kumar, managing director of KMRCL.
He added: ‘These types of tunnel-boring machines, which we call ‘earth pressure balancing tunnel boring machines’, have been used for the first time in eastern India,’
Another interesting point is that more than 10 lakh tonne of mud has been dug out for the construction of this tunnel.
The TBMs were used for the first time in eastern India. The entire stretch of the first tunnel, 16.6 km long, is finished. However, the second tunnel has yet to be completed.
Of the entire length, 10.8 kms is underground and around one kilometre is beneath the river at both ends.
‘For tunnelling below the river, the water tightness, waterproofing, and the design of gaskets were the major challenges, because the tunnel is being constructed for a service of 120 years, so we cannot afford any water leakage during service,’ said Kumar.
Tunnelling work cannot be carried out for too long, so much work was done – for almost an year – prior to machines and equipment being shifted to the location for final implementation and execution of the plan.
The material used has measures to help protect it in quakes in seismic zone 3, in which Kolkata falls.
The use of the standard gauge makes it a unique one. It is the latest technology that has been used to ensure that the tracks have sharp curves, keeping in mind that this tunnel passes under a lot of heritage buildings.
The heritage buildings had to be protected, and the work was not supposed to stop even for a day in these buildings.
Puja Shukla, a local resident said: ‘I think it’s a good thing which is happening, because the Metro is the cheapest and the fastest form of transport, used by a large number of people which will also hopefully ease traffic on the surface.
This will be very beneficial in connecting people from all over Kolkata.’
Source : http://www.dailymail.co.uk