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Cleaning pipes by ice pigging

We are principally employing a technique called Ice pigging to clean the majority of the trunk main network.

Ice pigging involves isolating a relatively short section of pipe by turning off valves at each end. Water is then displaced to make room for ice solution to be injected. Once the ice solution is in place a valve is then re-opened. This then helps to compact and drive the ice through the pipe, removing any sediment as it goes. The ice is then flushed safely from the main and the water is sampled before the main is returned into supply.

This cleaning method offers a huge benefit to our customer’s in that it involves less excavations and causes less traffic disruption than traditional cleaning techniques. A further benefit is that the majority of this work will be carried out during the night which significantly reduces all forms of disruption to homes, commuters and businesses.

The Ice pigging process

What happens on the day?

Ice Pigging Process - Step 1

Step 1

The two large articulated vehicles contain the Ice solution (think very large Slush puppy) that is pumped into an isolated section of main via the blue hoses that run from the vehicles to a hydrant stand post.

Ice Pigging Process - Step 2

Step 2

The Ice solution (10m³ to 25m³) is injected via the hydrant stand post into the isolated section of main. During the injection phase the mains pressure is continually monitored to ensure there are no bursts as a result of this activity.

Once all the Ice solution is pumped into the main, an upstream valve is opened, allowing the upstream pressure to push the Ice all the way to its exit point – up 1600m away.

Ice Pigging Process - Step 3

Step 3

The Ice exit point is carefully and continually monitored to ensure the procedure is completed successfully.

Ice Pigging Process - Step 4

Step 4

The Ice flushing process is designed specifically to remove any of the harmless sediment from the water main that may have accumulated over many years of service. This sediment is diverted into large tankers so it can be disposed of in the most environmentally friendly way.

Ice Pigging Process - Step 5

Step 5

When the sediment has been removed, the main is flushed for a further calculated period of time to ensure it continues to meet with our stringent water quality standards before it is returned to service.

  • Will my water supply be affected?

    Occasionally customers may receive discoloured water as a result of cleaning activities. Affinity Water will be constantly monitoring the local network to reduce the impact that discolouration may have.

  • What should I do if my water supply is discoloured?

    Discoloured water is not harmful to health. You should run the first mains-fed tap in your house at a normal rate for up to 30 minutes. Metered customers who experience discoloured water as a result of this work should ring our customer centre on 0800 521 660, as you may be given an allowance on your bill.

  • If my water is discoloured, is it safe to use my appliances?

    Washing machines and dishwashers should only be used if your water supply is running clear.

  • Will I be notified if my water supply will be turned off?

    We will notify you of any planned interruptions to your water supply.

  • How can you help someone who needs special assistance?

    We have a database of customers who have specific water requirements, if you are concerned please contact us on 0800 521 660, and we will make arrangements to help you.

  • Will my water pressure be affected?

    We aim to carry out the majority of work during the night to reduce impact to customer, during cleaning works some customers ay experience changes to the pressure at their taps. If your supply is to be interrupted you will be given 48 hours notice.

  • Will my water quality be affected?

    Some customer may notice a slight change to the taste or odour following cleaning works, in the extremely unlikely event that you should experience a change in the quality of your water, please contact us on 0800 521 660.