CHENNAI: With Union home minister Amit Shah presiding virtually over the groundbreaking event of the 118.9km phase-2 metro rail project on Saturday, construction began with an excavator digging the earth for an underground station at Villivakkam. It will be among the few stations to be built in tough soil conditions.
A total of 23 tunnel boring machines (TBM) are expected to work in tandem to construct tunnels covering 42.6km for the phase which, with 128 stations along three corridors, is estimated to cost Rs 61,843 crore and is expected to be ready by 2026.
At Villivakkam, officials said, work has begun to relocate units of a Chennai Metrowter sewage pumping station, where Villivakkam metro station would be built under a densely populated area. Villivakkam is among the five stations between Retteri and Nathamuni on corridor 5 from Madhavaram to Sholinganallur, which has thick hard rock formations where building tunnels and stations could be an engineering challenge and pose a risk of slowing down work. Other locations identified with rock formations are KMC to Chetpet on corridor-3 and Nandanam to Panagal Park on corridor-4.
As stations start to take shape, tunnelling will begin in several locations at the same time as CMRL has split the underground section into small portions for awarding separate contracts to prevent delays. Officials said at least 15 TBMs will be operated at the same time to construct twin tunnels covering 26.7km on corridor 3, four TBMs each in 10.1km underground line of corridor-4 and 5.8km underground line on corridor-5.
During the launch of the project, chief minister Edappadi K Palaniswami requested Shah to intervene for early approval and Centre’s participation in the project with 50:50 equity sharing model. “Centre has suggested to provide only 10% cost as grant instead of providing 15% as share capital. Since Centre’s grant will affect the present share-holding pattern and such grant is also revenue expenditure, we have been requesting it to consider the support as share capital, which is taken as capital expenditure with a sharing pattern of 50:50 between Centre and state,” Palaniswami said. The CM also said the 9km phase-1 extension from Washermenpet to Wimco Nagar is expected to be commissioned in January 2021.