In a novel plan, Phase-II of the Chennai Metro will incorporate tunnels under two water bodies of the city, namely, Adyar river and Chepet lake, reports Times of India.

When Phase-II of the metro will become operational, commuters on board the trains will plunge 20 metres deep under the depths of the Adyar river and Chepet lake while travelling between Madhavaram and Sholinganallur.

To link four stations between Adyar and Chetpet, twin tunnels, stretching up to a kilometre, will be built. Soil testing for the same is currently being conducted, with samples being collected every 15-18 metres and 25-30 metres by drilling a 150mm borehole.

While the Adyar tunnels connect the Adyar junction station and Adyar depot station, those under the Chetpet lake will connect KMC station on Barnaby road with Chetpet station. These four stations form the 45.8km corridor of the 118.9 km phase-2 of the Madhavaram-SIPCOT line.

The two tunnels are part of a priority corridor for which funding is already done. With the tenders are due to be floated by June, the construction work is supposed to start by the year-end.

In phase-1, the CMRL, built two tunnels under Cooum river, between the Central Metro and Government Estate and Buckingham Canal near Central Metro, with a complex arrangement of rings to hold the soil above to prevent water seepage.