May 23, 2011
-- The multi-million pound project will see the contractor and project management team from Morrison Black & Veatch Joint Venture (MBV) creating a new waste water network. Explains Alastair Graham, Senior Project Manager at Scottish Water: “This project is part of an investment programme designed to help protect local coastal waters and rivers. Combined sewer overflows (CSOs) have traditionally provided an important failsafe to prevent storm water and domestic sewage from backing up and causing floods following heavy rainfall, however, the new waste water network will provide an equally efficient but much more environmentally friendly solution to this issue.”
The project has been divided into three parts: WP6.1 (Kilmarnock)
, WP6.2 (rising main from Gatehead up to and including a new inlet works at Meadowhead WWTW) and WP6.3 (Irvine). Within WP6.2, 4.5km of 1000mm PE pipe will be laid under largely arable land in the rural areas surrounding the Meadowhead WWTW, while 2km of 900mm PE pipe will be installed between the Drybridge Rail crossing (trenchless crossing) and Meadowhead WWTW. GPS has supplied the entire PE piping requirement for this project under an existing framework agreement with Scottish Water and all sizes have been supplied in SDR26 to accommodate the flow rates and durability required by the specification.
The pipe installation in the arable land areas of the project will involve straightforward excavation of open trenches and lengths of the PE pipe will be welded together and lowered into the trench, which will then be backfilled. In the areas below Irvine and Kilmarnock, the installation will be much more challenging as existing services will have to be diverted and where services are very congested or there are rivers or dual carriageways, the contractor will construct tunnels. Within the tunnelled areas, the PE pipe will be substituted for ductile iron pipe and these sections will be joined to the PE pipe using flange connectors.
Adds Stewart Cochran from MBV: “This is a complex installation but, once completed in 2012, it will provide a durable and environmentally responsible approach to managing waste water levels following heavy rainfall.”