The contract for construction of a new 5km CSO storage tunnel to alleviate flooding in the south of Glasgow, Scotland, is confirmed as design-build.
Representatives of Scottish Power gathered in Germany to accept the 4.7m diameter Herrenknecht EPBM that will begin excavating the 5km Shieldhall CSO tunnel in Glasgow next year (2016).
The machine, which will now be disassembled and transported by sea to Scotland, has been procured by the Costain/Vinci JV that expects to complete on site preparatory work by the Spring of next year (2016).
“It was great for members of the Shieldhall tunnel team to see the TBM up close and personal for the first time and appreciate just how big and complex it is,” said Paul Kerr, Scottish Water’s General Manager of Capital Investment.
Tunnelling on what will be Scotland’s largest ever CSO tunnel is scheduled for completion in 2017.
Project owner Scottish Water told TunnelTalk that a procurement process for engaging a contractor for the £100 million (US$150 million) project began in October last year (2012). A spokesman declined to reveal what stage the process had reached, or give details of prequalifiers, but confirmed that its engaged design consultant is CH2M Hill and that the tunnel will be segmentally lined.
The 4.65m diameter TBM-bored tunnel, which will run between Queen's Park and Craighton Industrial Estate to the south of the city, is part of a £250 million five-year package of publicly funded measures to upgrade the aging wastewater infrastructure in Scotland's biggest city. Construction is expected to last three-and-a-half years, with a scheduled start date of mid-2014. The TBM will launch from a shaft in Queens Park and work northwards under Pollock County Park and the M77 motorway, with the alignment finishing near the M8 (Fig 1).
The project is the largest investment in the Glasgow sewage network since Victorian times. The new CSO tunnel will transfer combined sewer overflows and provide stormwater storage capacity in the event of heavy rainfall.
"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 flood events in a number of areas that have been prone to them," said Geoff Aitkenhead, Scottish Water's Asset Management Director. "The tunnel will increase capacity and alleviate pressure on the existing network by providing additional storm water storage."