Caledonia Water Alliance (CWA) has successfully tunnelled below the Dumfries to Kilmarnock railway line as part of Scottish Water’s £120M water supply investment programme.
CWA used a tunnel boring machine (TBM) to drive the 130m long, 1,500mm diameter tunnel below the rail line in just under a month.
Scottish Water described the tunnel as the “missing link” in a 21km stretch of the water main from the Amlaird Water Treatment Works to the Highlees reservoir near Dundonald in East Ayrshire.
The TBM was launched from a 3.5m deep shaft on one side of the railway on 30 April and arrived in a 16m deep reception shaft on the other side this week.
“We are continuing to make good progress with the project and this latest piece of work to install the tunnel was a very important part of that,” said CWA senior construction manager Sean Lavin.
“We are delighted to have completed the work under the railway, which involved a lot of careful planning and close liaison with Network Rail and Scottish Water Special Services, who deal with land, environmental and planning issues.
“We carried out detailed site investigation work, including the drilling of vertical boreholes to analyse the geology before the tunnelling started, and some intricate work using hi-tech equipment to construct the tunnel and install this stretch of the new water main.”
Scottish Water has said that the new expanded network will enable it to provide customers with greater security of supply and to respond more effectively to operational issues such as burst water mains and minimise disruption to customers.