Huge underground water pipe cleaned
15 Sep 2011
Engineers have set to work cleaning giant water pipes in a tunnel 90ft under the River Mersey and the Manchester Ship Canal in Liverpool.
The pipes run about 400 metres through the tunnel, part of the Vyrnwy Aqueduct, and supply nearby homes with millions of litres of water every year.
United Utilities workers are cleaning the entire aqueduct which runs from Lake Vyrnwy in Wales all the way to Prescott treatment works just outside Liverpool city.
The cleaning operation is expected to last until 2020.
United Utilities's John Butcher said: "Everyone is familiar with the Mersey road and rail tunnels but the Mersey water pipe tunnel has a considerably lower profile. When engineers built the original tunnel back in 1881, they used pioneering compressed-air techniques to stop the structure from collapsing under the weight of river water. Even so, it required three attempts before they finally got it right."
Copyright Press Association 2011