Three Valleys Water is replacing the worn-out sections of the old cast iron water mains (some of which are 70 years old) with new plastic pipes, to reduce the number of burst mains. The work is being carried out by three of our contractors, namely Balfour Beatty, Hollerans and Enterprise.
How will we replace the water mains?
A number of techniques can be used to replace the water mains. We select the technique most appropriate for the local environment and in terms of minimising impact on the community. The four main techniques used are as follows:
Pipe Bursting
A plastic pipe is pulled through the existing iron water main, breaking the original pipe as it moves along. Pipe bursting means that we can position the new water main, exactly where the old main was and do not have to dig a trench.
Lining
A plastic pipe is pulled inside the original pipe that has already been cleaned. The type of lining will either be a loose or close fit depending upon the size of pipe that is required.
New Lay
Where necessary we shall install the replacement pipe using conventional trenching. This involves excavating a long trench usually alongside the old water main, into which the new pipes are laid.
Directional Drilling
Directional Drilling uses a steerable cutting head to drill a pilot bore underground to establish the line that the new pipe will take. When this pilot bore is completed the new polyethylene pipe is pulled back through the pilot bore to complete the installation.
Our aim when choosing the technique used is to minimise our impact on local residents, businesses and commuters.
