The minister's visit came after Prime Minister Narendra Modi asked him to personally supervise the work being done along and under the river Ganga. During his visit, Mr Supriyo collected soil from the place and kept it in two utensils. One of which he plans to gift to the Prime Minister, while the other to keep for himself as a memento.
Speaking about his experience, Mr Supriyo, who is the Minister of State for Heavy Industries and Public Enterprises said, "We reached almost the bottom of the Ganga and spent a considerable time (there). It was an exhilarating experience. I salute the engineers and the workers for the heroic work."
Speaking about the safety of the project, he said, "Let me allay any apprehension about the safety. We did not feel uncomfortable inside though we were 32 meters below the river water - that is the sea level." He also said that the latest technology is being used for the project.
The tunnel is being built by South African company Afcons-Transtonnelstroy between Howrah Maidan and the proposed Mahakaran metro station near Writers Building - a heritage site - in Kolkata. The length of the section from Howrah Maidan to the Ganga bank will be 1.7 km.
The corridor is expected to have delays because of many heritage building in its way. Answering a question regarding delays, Mr Supriyo said, "There are three heritage constructions - two synagogues and the Currency Building within 30 meters of the proposed tunnel. But IIT-Kharagpur, in a feasibility study, said the tunnel work and metro movement would not cause any damage to the structures...We are not setting up a time-frame. The Union cabinet is preparing a note to exempt the Metro work. Let's hope for the best," he said.
Thanking Chief Minister Mamata Banerjee for ensuring that encroachments were removed along the route in Phase 1 of the East-West Metro Corridor Project, Mr Supriyo said, "During my chance meeting with the West Bengal CM in 2015 which the media had christened as 'Jhalmuri diplomacy,' I had broached the topic of encroachment and with the intervention of Trinamool leaders it was resolved."
The second phase of the Kolkata Metro is being funded entirely by the central government.