A major milestone has been reached on a £17 million environmental project in Paisley.

A Microtunnel Boring Machine (MTBM) has started work to build a one mile-long waste water tunnel/sewer as part of the scheme, which will improve the water quality and natural environment in two local rivers.

Contractors Amey will develop the large diameter interceptor sewer, starting at Bridge Street car park and going across the Watermill Hotel car park and Lonend before going along Saucel Street, beneath Saucelhill Park and the railway line near Canal Street Station, Espedair Street, Rowan Street and Kilncroft Lane/Neilston Road.

The 'Abbey' MTBM was launched at one of the 15 shafts along the tunnel route and will install the first third of the tunnel. The structure will be 1200 milimetres in diameter, while two other machines will install the second and third stretches of the tunnel, which will be 1500 milimetres and 1000 milimetres in diameter.


Removing around 45 – 50 tonnes of earth per day, the tunnel will be installed by the pipe jacking method with individual sections of concrete pipe installed sequentially and jacked into position to the rear of the MTBM once the machine has removed the soil. It will be installed mainly in mudstone and siltstone. Overall, the new stretch of sewer will have a diameter of up to 1.5 metres and will be installed at depths of between 4m and 20m.

Brian Boland, the project manager, said: "We are delighted to have reached this milestone on the project, after a lot of preparatory work, and to have lowered the tunnel boring machine onto position at the launch chamber.

"Once it was assembled below ground, the machine was presented to the rock face and has now started its work on boring through the earth and installing the pipe. After four years of planning this project, in liaison with the Scottish Environment Protection Agency (SEPA) and Renfrewshire Council, it is great that the tunnelling proper is now under way."

The £17m project also includes the installation of Combined Sewer Overflows (CSOs) in the town centre, reducing the frequency of spills from the sewer network into the Espedair Burn and White Cart Water in storm conditions.

The investment is part of Scottish Water's £250m, five-year programme of work to improve river water quality and the natural environment and tackle flooding across the Greater Glasgow area.

Work on the project started last October and is expected to take two years to complete.

(LM/MH)