Metro’s big leap across river (Times of India 19 June 2011)

NEW DELHI: The third phase of the Delhi Metro, which will connect Mukundpur with Yamuna Vihar, will throw up a number of firsts. At 55.69km, it will be the longest alignment on the Metro network and will have around 10 interchange stations — the most so far. Its two stations, Hazrat Nizamuddin and Mayur Vihar Phase I, will be over 4.5km apart — the longest stretch on the network. And to top it all, a new station will be constructed above the existing Mayur Vihar I station to integrate the two lines.
A Delhi Metro Rail Corporation spokesperson said, "The stretch between the two stations will be the longest on the entire network. It will be built on a bridge spanning the Yamuna."
The Hazrat Nizamuddin station, which will be underground, will provide easy access to the nearby Nizamuddin
At the other end, the line will integrate with the Mayur Vihar Phase I station. And as part of this integration, a new station will be constructed above the existing one.
The corridor will arch over towards Trilokpuri, going over the present Dwarka-Noida alignment.
Officials admit the 4.5km stretch from Hazrat Nizamuddin to Mayur Vihar will be another challenging piece of engineering in the Metro project. The official said, "We plan to use segmental launching technology, which was also used for the bridge after Yamuna Bank station on the Dwarka-Noida corridor." The bridge will span 602.8m across the river. According to officials, this technology involves pulling up segments using launchers.
DMRC officials say that the pillars, or piers as they are called, will be anchored in the riverbed.
"These will be built using well foundation technology that will enable the groundwater to recharge as well as rainwater harvesting," added the official.
On the piers, metallic strips with gauge marks will also be put up to indicate the flood level. The stretch will run between the Delhi-Noida toll road and Nizamuddin flyover, over the Zone 'O' of the Delhi Development Authority (DDA).
Incidentally, the zone has strict building norms, with the DDA refusing non-green projects in the area in the past. But Delhi Metro officials said that permission wasn't expected to be a problem, as transport solutions were allowed under the current norm in the zone.
The Hazrat Nizamuddin and Mayur Vihar Phase I
stations are expected to cater to residents of a large number of nearby colonies, including Nizamuddin East, passengers coming from the Nizamuddin railway station and Sarai Kale Khan ISBT, apart from Mayur Vihar, Pratap Nagar, Patparganj, Shashi Garden, Maharaja Agarsen College and Acharya Niketan.