The £100m sewer tunnel will run between Queen’s Park and Craigton industrial estate via Pollok and Bellahouston parks.

It will be the biggest storm water storage tunnel in Scotland and will improve water quality and reduce flooding issues at key locations in the area served by the Shieldhall Waste Water Treatment Works.

The tunnel will be a major part of Scottish Water’s £250m, five-year programme of work announced in February to upgrade the waste water network in the Glasgow area.

The tunnel will be 4.65m in diameter – big enough to fit a double-decker bus inside – and more than five times as long as the Clyde Tunnel.

Construction is expected to start in mid-2014 and take three and a half years to complete, including preparatory work, mine working consolidation and utility diversion work.

Bidders are believed to include Barhale and Carillion.

Geoff Aitkenhead, Scottish Water’s Asset Management Director, said: “Following the launch in February of our five-year programme of investment to transform the Greater Glasgow area’s waste water infrastructure, we are delighted to be able to confirm this key part of the programme.

“The Shieldhall tunnel will resolve large-scale water quality problems in the River Clyde and its tributaries, provide aesthetic screening to overflows into watercourses such as tributaries of the Clyde and White Cart Water and reduce the risk of flooding in Aikenhead Road and Curtis Avenue in Mount Florida and Robslee Drive, Robslee Road, Robslee Crescent and Orchard Park Avenue in Giffnock.

“The tunnel will increase capacity and alleviate pressure on the existing network by providing additional storm water storage.”

It will be constructed using a specially designed tunnel boring machine which will follow a route from the Queen’s Park area towards Pollok Park.