Water Mains Cleaning

Ice Pigging™ is the fastest and safest method of cleaning drinking water pipes:

Fastest – because water mains cleaning with Ice Pigging™ can be up to 200 times quicker than legacy methods. It takes hours not weeks, allowing continuity of the mains water supply.
Safest – because there are no excavations and no high-pressure pipe cleaning, meaning a low risk of leaks or damage to infrastructure. Afterwards, drinking water is free from discolouration too.

Using our unique ice slurry system, Ice Pigging™ can clear several kilometres of main in just a few hours, cleaning pressurised pipes far more thoroughly than flushing alone, as this video shows …

The process

Drinking water pipes need cleaning for several reasons but the most frequent if when a customer complains of mains water discolouration. Occasionally when a trunk main’s flow is reversed, many years of accumulated sediment will be suspended, leading to increased turbidity or lack of clarity, potentially affecting thousands of consumers. Another reason is when there is an older infrastructure. With many water systems having elements that are up to 100 years old, trunk main deterioration is now becoming an issue – leading to increased pipe debris. Changes to the network like overhauls, changing flow rates, bursts and valve operations. Biofilm build-up can lead to many issues like an increase in bacteria levels and a loss of chlorination levels which indicate that the mains need cleaning.

Reasons to clean drinking water pipes:

Discoloured water

Turbid water causes many complaints. Sediment removal from water mains is fast and easy with Ice Pigging™. This discolouration, or turbidity in the water is normally caused by overhauls, network changes, bursts, or flow reversals disturbing sediment accumulated over the years.

Clean drinking water pipes for flow reversal

Knowing in advance if water mains are to be used in reverse flow, it’s prudent to clean them first to avoid turbidity in drinking water. Ice Pigging™ can thoroughly clean many kilometres of pipe in a few hours.

Water pipe debris removal

Debris in water pipes can be caused by sediment entering the water at treatment plants or even physical degradation of older pipes. The unique Ice Pigging™ system removes all debris, quickly and cost-effectively.

Remove biofilm from water mains pipes

Biofilms are organic and inorganic material normally found in patches on the inside of pipes. They’re responsible for a wide range of water quality and operational issues. Ice Pigging™ is by far the most effective way of removing biofilm.

Improving water quality

The overall quality of water (including taste, odour and clarity) will be greatly improved by the removal of debris, biofilm, chlorine residuals and other contaminants. Only Ice Pigging™ can offer a fast, low-risk cleaning service in hours, not weeks.

Our mains pipe cleaning service

Ice Pigging™ can clean many kilometres of pipe overnight. Our fully crewed trucks deliver our service to many water companies throughout the UK. The Ice Pigging™ water mains service is fast, painless and low-risk.

Ice Pigging™ is far more effective than other pipe cleaning methods and because of our ice slurry’s unique formulation, it’s not stopped by reduced diameters, bends, unions or control valves along the main.

This is what to expect when you engage with our Ice Pigging™ service:

Isolate the main The main is isolated by closing valves upstream and downstream of the section to be cleaned.

Insert the ice The ice slurry is pumped into the pipe via a fire hydrant or similar fitting. A ‘pig’ of ice is formed, with the displaced water discharged at the outlet fitting.

Open upstream valve The ice is pushed along the pipe using the natural pressure in the network. To do this, the upstream valve is opened and flow at the outlet hydrant is used to control the speed of the ice. As the ice flows through the pipe it passes over every surface and collects sediment or wipes biofilm as it passes.

Collect Ice Pig™ Water in front of the pig is discharged normally. Temperature at the outlet point warns of the arrival of the ice, which allows the sediment laden ice to be collected separately in a tanker if desired.

Flush and return to service The pipe is then flushed to the appropriate standard and promptly returned to service. The process is efficient, rapid and exceptionally low risk.

All operations are carefully monitored in real-time by our specialist engineers using our Flow Analysis System.

Ice pigging vs traditional pigging

Don’t confuse Ice Pigging™ with other types of pigging to clean water pipes. With those, a solid or foam ‘pig’ is pushed through for sediment removal or addressing a pipe blockage. Unlike ice pigging, they cannot cope with small radius bends or different diameters of pipe. Essentially these ‘solid’ devices are mainly for sediment removal in straight pipes and do not have the flexibility of ice pigging that never gets stuck.

Ice Pigging™ is normally the fastest and most cost-effective way to restore clean drinking water.

Time: Several kilometres of trunk main can be cleaned in 2-3 hours, distribution pipes take only minutes - Minimum disruption to supply.

Cost: Highly cost effective at a whole project level.

Ease: Ice is inserted and ejected using existing hydrants, no network modifications are required. Pig flows through all pipe diameters, fittings, and topographies.

Low risk: Exceptionally low risk – if ever the ice gets stuck, it will simply melt.

Effectiveness: A physical clean is undertaken rather than just a flush. Quantifiable results show the amount of sediment removed from the network.

Environmental Benefits: The Ice is harmless to public health - no harmful chemicals are required.

Ice pigging vs water flushing

Water flushing is ineffective compared to Ice Pigging™ in most cases. Our tests have shown that our process is far quicker too. It uses less water than hot or cold water flushing and is low-risk compared to other methods as if the ice pig gets stuck, we simply wait for it to melt. The whole process is environmentally-friendly and typically no excavations are required.

Ice pigging is not only used for sediment removal; it also removes biofilm, thus greatly improving the quality of clean drinking water.

Case Study: Water main flow reversal required ice pigging

“The pipe was cleaned over two nights with the main isolated for only 6 hours in total, resulting in no customer disruption and over 323kg of material removed from the two sections. Ice Pigging™ has allowed the company to reverse flows in a pipe which previously, would have been impossible at such short notice.” Welsh Water

The Issue: main flow reversal

A reservoir was being taken out of service. As a result, the flow needed to be reversed on a trunk main serving around 9000 consumers. Reversals represent a significant change to the balance of a network and sediment can easily be suspended, resulting in discoloured water. The client decided to clean the pipe prior to undertaking the flow reversal in order to effect sediment removal.

The Solution: overnight ice pigging

SUEZ cleaned 2.5km of water mains which were DN400 cement lined ductile iron pipes. The ice pigging took place over two nights, with the main isolated for just three hours each night. There were minimal enabling works required and no excavations. Post cleaning disinfection wasn’t required, and the mains were directly returned to service without disruption to clean drinking water.

The result: mains water system cleaned with no service disruption

Sediment removal resulted in over 323kg of material recovered.
Biofilm and debris were removed at the same time resulting in better water quality.
The water flows were reversed at short notice.
No customer disruption reported.

The Ice Pigging™ team have 90 years of experience developing and delivering this award winning, patented technology across a variety of sectors worldwide. If you want to know how Ice Pigging™ can solve issues with your pipework systems and processes, save you money and make your cleaning processes more efficient, get in touch.