The planned 1.8km-long tunnels are part of United Utilities’ scheme to clean up the long-troubled Salteye Brook in Salford.

Once complete the tunnels will provide sufficient storage capacity during heavy storms to prevent uncontrolled discharges.

The project forms part of a £90m clean-up that will bring back fish to the historic waterway.

Work will begin on the project in early 2015, with the construction of deep shafts.

Tunnelling will then start in the Spring 2015 with an anticipated finish a year later.

The tunnel route  start next to Junction 11 of the M60, passing below and then parallel to the motorway and on into the Eccles waste water treatment works.

The tunnel alignment then heads under the M60 Barton High Level Bridge parallel with the Manchester Ship Canal, then past the Salford City Reds rugby stadium to a new outfall structure at the Port Salford Locks.

While tunnelling is underway, work will begin on a complex outfall structure adjacent to Port Salford Locks on the Manchester Ship Canal.

This part of the scheme is expected to be complete in Summer 2016. The contract also includes M&E packages.

Both tunnels are concrete lined at 2.1m and 2.85m internal diameters.

Matt Crabtree, Costain Water Sector Director said: “The route crosses below the M60 Barton piers, narrowly avoiding raking piles from the bridge pier structures.

“We will continuously use the latest survey monitoring technology in real time to monitor bridge and highway structure movement before, during and after the TBM completes its journey.”