The mission

United Utilities Group PLC (UU), manages the regulated water and waste water network in North West England which includes Cumbria, Cheshire, Greater Manchester, Lancashire and Merseyside which have a combined population of nearly 7 million.

A build-up of manganese and iron was present in four lengths of water main. Due to inaccessibility of the areas identified traditional cleaning methods such as swabbing or air scouring were likely to prove very difficult if not impossible. One particular length of pipe was even deemed “uncleanable” by United Utilities.


Key requirements:

  • Keep water usage to a minimum
  • Minimise customer disruption
  • Remove sediment build-up within the pipes

The results

Ice Pigging™ was proposed over traditional cleaning methods due to its ability to easily flow through changing pipe diameters, bends and fittings without requiring any excavations. Once inserted into the pipe, the ice pig catches and carries all sediment along to the outlet point. This particular operation was carried out overnight and the total length of pipe cleaned was 1517m of 225-300mm diameter pipeline.

  • Average volume of water used: 1.25 x pipe volume
  • Main returned to service in 2 hours
  • Total volume of sediment removed: 96.7kg
We are really impressed with the standard of work, level of professionalism and all round well done for the job.
John Cott , Project Manager | United Utilities