27 May 2010
Engineers from United Utilities are this afternoon (Thursday May 27) making final preparations to repair the 36" valve at the centre of the recent water supply problems in the Wirral.
The work has already involved isolating power lines, preparing two temporary stop valves and excavating a series of trenches up to nine metres deep.
This afternoon specialist teams are installing extra equipment, including a booster pump to help maintain local water supplies while the work is under way.
There is no intention of shutting off water supplies while the work takes place. The giant super tankers which have been used to maintain water supplies to the local area over the last few days will continue to pump clean, chlorinated water into the mains. Other tankers will also continue their important work maintaining water levels at Gorsehill Service Reservoir.
The valve, which is inside an underground chamber on open land opposite Upton railway station, appears to be broken in a closed position.
In order to work on it safely, a mile and a half long section of pipe needs to be shut off at both ends, between the two temporary stop valves, and the water inside it drained away into a local brook.
United Utilities has been working with the Environment Agency to make sure releasing the water does not affect the brook. The brook will be lined with straw bales to prevent erosion of the banks and de-chlorination equipment will be installed to remove chlorine from the water. Chlorine is the disinfectant used to keep water clean in the supply network.
A total of 1.4 million litres of water needs to be discharged into the brook in a slow and controlled way over a period of about 10 hours. This process is expected to begin later this evening.
Valve repairs will follow, after which the main will be re-filled. The main will then need to be emptied and re-filled a further time to make sure drinking water is the best possible quality.
The entire process is expected to take until the early hours of Sunday morning.
Scott Beard, Regional Water Network Manager, said: "This is a critical stage in our restoration project. It is a complex job and we have made a lot of very detailed preparations to get ready for it. From start to finish it will take more than two days but there are no short cuts we can take. We want to restore the water mains network to its normal operation so that those customers who are still suffering from intermittent pressure get the high-quality service they are used to and deserve.
"It is just possible that some residents in Upton, Frankby, Woodchurch and Beechwood may notice slightly less pressure or a slight change in the colour of their water during times of high demand, such as breakfast and teatime, during this period. However the booster pump we have installed should help prevent this from happening."
United Utilities has confirmed that compensation will be paid to those affected by the incident and to customers in Moreton, Leasowe, and Wallasey areas of Wirral who were affected by a water loss incident last week.
ends
CAPTION: Engineers installing the new temporary stop valve near Prenton, which will be vital to isolate the faulty valve, which is a mile further along the water main near Upton.