Nearly a mile long and 40 metres below the ground, a tunnel boring machine made its way through to the terminal pumping station in the deepest open excavation in the city’s history.

The Belfast Sewers Project involves upgrading the existing sewers and increasing the storm water capacity to prevent the risks of flooding.

Up to four million gallons of storm water will be able to be stored in the new tunnel reducing the risk of severe flooding to the greater Belfast area.

Katharine Bryan, chief executive of Northern Ireland water, said: “NI Water has a massive programme of water and wastewater infrastructure investment underway.

“This involves an investment of million pounds every working day in schemes which will benefit homes and businesses. I am delighted that we are well on track to bring such large scale benefits to the city.”

Completion of the Belfast Sewers Project is scheduled for 2009 and is a joint venture with contractors Morgan and Farrans Construction.

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