Spring clean for Tiverton water main
Tiverton's trunk main is to get a spring clean - using ice crystals.
South West Water will be carrying out planned maintenance on the water network from 11-14 April.
Over time very low levels of iron and manganese present in all water supplies build up on the internal surfaces of water mains. If these are disturbed due to a sudden change in flow or pressure (caused by a burst main, for example) customers may notice their water appears discoloured.
To avoid this inconvenience, South West Water periodically removes any build-up in a controlled and planned way.
An ice solution, similar in consistency to a Slush Puppy or granita drink, will be pumped into the isolated water main. Once a suitable plug of ice has been introduced it is driven along the pipe by water pressure - the same water that would normally be flowing in the pipe. The plug of ice is driven at a speed that's most effective at removing any deposited minerals.
Operations manager Jason Harvey explained: "The process makes use of the characteristics of ice crystals in a water solution to essentially scrape off and then encapsulate any deposited minerals within the plug of semi-solid ice.
"The plug of ice is driven through the main until it reaches a pre-planned exit point - normally a fire hydrant. The ice is collected and removed off-site for appropriate disposal.
"During the whole process the quality of the water in front, within and behind the ice plug is carefully monitored.
"Once the cleaning team are completely satisfied the level of clean has been achieved and the water has returned to its normal excellent quality, the pipe will be returned to service."
Around 250 customers will be given advanced notice of the interruption to their supply, which will last for up to a maximum of four hours. Customers are advised to fill a jug or two of water to tide them over.
The water supply should quickly return to its normal excellent quality following the cleansing operation, but if customers notice any change in appearance or taste they are advised to run their kitchen tap for a couple of minutes.
There's more information about the ice crystal cleansing process here.
