The Phase-III Metro expansion will not only be the largest but one of the most challenging for the DMRC. Its network will run through congested lanes of East Delhi,under railway lines and below existing routes.
For the first time,four tunneling stretches will pass below the underground lines,posing a major construction challenge. In Phase-II,only one new corridor crossed below an operational corridor at Connaught Place.
The underground stretch from Sarojini Nagar to INA on the Mukundpur-Yamuna Vihar corridor will pass below the underground section of the Jahangirpuri-Huda City Centre line at INA. The Janakpuri West-Botanical Garden corridor will cross existing routes at two locations.
The underground stretch from Indira Gandhi Domestic Airport (T2) to Vasant Vihar will pass below the underground section of the Airport Express Link near the Indira Gandhi Domestic Airport. The stretch from Hauz Khas to Panchsheel Park will pass below the underground portion of the Jahangir Puri-Huda City Centre stretch at Hauz Khas.
The stretch from Mandi House to ITO on the Central Secretariat-Kashmere Gate corridor will pass below the underground section of the Noida-Dwarka corridor at Mandi House.
The construction at these locations is being done using sophisticated equipments to ensure that Metro operations on both the routes are unaffected due to the crossovers. The passage from the both tunnels new and old will be smooth and without any disruption, the official added.
The proposed new corridors will cross operational corridors at 14 different points. While 10 of these will be under operational stretches,four will be elevated above operational viaducts. Elevated viaducts have not crossed each other so far in the Metro network.
The tunnels are going to pass under railway tracks at Palam and Tilak Bridge. Near Nizamuddin Metro station,tunnels will be made in an area of high groundwater level. The tunnels will be made under high-rise buildings,flyovers along Ring Road and important locations, the official said.
Sites in East Delhi will pose another challenge. The Mukundpur-Shiv Vihar corridor will travel through congested pockets like Trilokpuri,Kalyan Vas,Vinod Nagar,I P Extension,Anand Vihar,Karkarduma,Welcome,Seelampur,Jaffrabad and Maujpur.