United Utilities has reached a significant milestone in its Vyrnwy Aqueduct Modernisation Programme (Vamp), which aims to upgrade 139 kilometers of pipe infrastructure that serves nearly one million customers across Cheshire and Merseyside. This ambitious eight-year project, which commenced in 2022, is designed to enhance the region’s water supply system, stretching from the company’s water treatment works at Oswestry to Prescot.
The Vyrnwy Aqueduct, operational since 1892, consists of three parallel pipes that transport water from Lake Vyrnwy in Wales to Merseyside, supplying approximately 12% of the raw water for the North West. Each day, the aqueduct delivers up to 210 million liters of drinking water to communities in Cheshire and Merseyside.
As part of the modernisation, two of the original cast iron pipes will be lined with state-of-the-art polyethylene materials. This upgrade not only ensures the water remains safe and high-quality but also eliminates cast iron deposits that can cause minor discoloration. This method aligns with United Utilities’ commitment to maintaining high drinking water standards in the region.
To further enhance efficiency, United Utilities has set ambitious water-saving targets for contractors Avove and OCU, focusing on reducing the project’s carbon footprint. Innovative engineering solutions are being employed to tackle complex segments of the aqueduct, including areas with challenging bends and urban congestion.
One of the standout technologies being utilized is the “pipe pusher,” capable of pushing nearly two kilometers of piping at once—more than double the 900 meters achievable with traditional methods. This innovative approach minimizes the need for extensive excavation and reduces community disruption.
Additionally, United Utilities has introduced a technique known as air pigging for the upgrade of the third pipe, which works on larger sections up to 42 inches (1,067mm) in diameter and 2.6 kilometers long. This method employs a steel bitumen lined pipe to remove over 100 years’ worth of manganese and iron deposits that have accumulated since the aqueduct's installation. Compressed air is utilized to force the lining through the pipe, and this process is repeated using “pigs” with different scouring covers to ensure a snug fit for the liners.
Air pigging is not only quicker but also appears to be more effective than traditional jetting while using considerably less water, according to United Utilities. Given the expansive scope of the Vamp, a staggered construction approach has been adopted, digging at intervals of 800 meters to maintain a continuous water supply while future-proofing the infrastructure.
This modernisation initiative is a significant investment in the region’s water supply system and underscores a commitment to sustainable and effective water management practices in North West England. The regional delivery manager for the Vamp expressed satisfaction with the progress made on this extensive and innovative project, which spans a vast area of the region.
“We’re really pleased with progress on this extensive and innovative project, which spans such a huge part of our region. We have trialed and tested new technology, worked with local authorities and stakeholders to manage timelines, and engaged with landowners and occupiers in more than 70 areas of privately owned land,” the manager stated. “We continue to engage with the local community from the full stretch between Malpas and Prescot, and we’re pleased to say that overall, they have been very welcoming and understand why it needs to happen.”
The manager also highlighted the collaborative efforts with construction partners Avove and OCU, stating, “What we have achieved just in the first three years of this programme is due to the incredible effort from all of the team. We are continuously learning and adopting new approaches as we progress.”
To keep the public informed, United Utilities has launched a dedicated website where updates on the project, images of its progress, and the benefits—both short and long-term—can be accessed at any time.
As the project accelerates into its final three-year phase, United Utilities extends gratitude to its customers, constituents, and communities across Cheshire and Merseyside, emphasizing their commitment to a stronger, greener, and healthier North West.
In addition to the Vamp, United Utilities has partnered with Groundwork, Cenergist, and various business water retailers to conduct water efficiency visits to organizations across the North West. These efforts have led to the identification and repair of leaky taps, toilets, and showers, resulting in a remarkable savings of 3.8 million liters of water daily—enough to fill one and a half Olympic-sized swimming pools.
Alice Denholm, Water Efficiency Delivery Manager at United Utilities, explained, “The North West is one of the rainiest areas in the UK, and we know that saving water isn’t always something people think about in the same way they do about saving energy. But water is a precious resource, and we can all play our part in saving it one drop at a time.”
Denholm highlighted the ambition to help as many organizations as possible reduce water use and save money. “To help us achieve this, we worked with several water retailers across the region. They did a great job engaging with their customers to encourage take-up,” she added.
Among the participating retailers was Water Plus, whose Head of Technical Water Efficiency, Scott MacIndeor, stated, “It’s been brilliant to be involved in this, drawing on our experience in this area with customers, engaging more than 3,600 businesses and public sector locations, so they become more water efficient and make financial savings.”
As United Utilities continues its commitment to improving water services and efficiency, the organization remains focused on innovative practices to secure a sustainable water future for the North West region.
