MOST of us associate burst pipes with severe cold in winter, but prolonged warm weather can also lead to problems.

“In summer, as the ground dries up and compresses the pipe, and customers use more and more water, creating more pressure on the pipes,” explains Joe Hands, Yorkshire Water’s north west area service delivery and leakage manager. “With older pipes, this can create bursts.”

He adds: “We have more customer contact in summer, due to leaks and bursts.”

The network is made up of 32,000km of Yorkshire Water-owned pipes and 30,000km of customers’ pipes. Joe covers an area stretching west from Bradford to High Denton near Kirby Lonsdale on the edge of the Lake District, across to Harrogate and into the Yorkshire Dales, and east across the North York Moors to Whitby.

Yorkshire Water has almost halved the amount of leakage since 1995 and the company plans to reduce it by another ten million litres a day by 2020.

This is as a result of increased leakage detection through various techniques, run alongside a programme of pressure management. Total leakage is estimated as the sum of distribution losses plus leakage from customer-owned supply pipes.

Over the past five years the network’s total leakage figure is an average of 280 megalitres a day - around 112 Olympic-size swimming pools - below the target of 297 set by the water regulator Ofwat. That figure is being reduced over the five year period beginning in April 2014.

“It is a challenge but one which we will do our best to meet - it has been steady over the past few years, and we have been well within the target,” says Joe. “The regulators drive us hard on leakage - it demonstrates our efficiency as a business.”

In Bradford district 85 per cent are cast iron and are between 50 and 80 years old. The remaining 15 per cent of pipes have been replaced in materials including durable plastic and steel.

“We have one of the oldest networks in Europe,” says Joe. “Cast iron pipes are prone to changes in temperature - as it gets colder the material in the iron shrinks causing the pipe to contract and the ground around it to move. This weakens its structure - miniscule holes can enlarge, leading to bursts."

He adds: “The contraction of a pipe with no holes can also cause bursts.”

The optimum conditions for water pipes, creating minimal problems, is, says Joe “overcast, mild weather.”

“The older pipes are being replaced on a rolling programme,” says Joe, “It is carried out to ensure minimal impact on customers. We are just completing work in Ilkley and Keighley.”

By 2020, Yorkshire Water will have invested £75 million to replace 226km of water mains.

Various leak detection methods are used. The network has within it thousands of logging device, or ‘nodes’ - wireless technology that gathers data. They can record how much water is running through pipes, how much water is being used by customers and how much is unaccounted for. This way staff can calculate whether there may be a leak.

“It lets us know back at headquarters, where our analysts direct people working out in the field,” explains Joe.

“Reducing and stopping leaks is one of our biggest priorities. We are focused on leakage and on reducing its impact on customers.”

Customers are encouraged to report leaks if they spot one, or if they think they may have one - sometimes due to an unusually high metre reading at their property.

“Our customers react quite quickly. Often the first we hear about a leak is when a customer contacts us to tell us about it.”

Pulses or signals can also be transmitted along pipes, with any changes indicating a possible escape of water. “We also use gas injection,” says Joe. In these cases, a combination of nitrogen and hydrogen gas is injected into the mains. If there is a leak, the gas will then escape from the faulty areas of the pipe. A gas detector is then used to help find the source of the problem.

Alongside high-tech detection methods, techniques dating back centuries continue to be used, and are still effective. Rudimentary-looking listening sticks transmit leak noise to the listener through vibrations from below ground.

Working day and night, leakage teams do not only respond to reports of escaping water - they pro-actively search for leaks and attend to them as quickly as possible..

*For more information visit yorkshirewater.com Leaks can be reported by contacting Yorkshire Water’s free leakline number 0800 573553.