For staff at Yorkshire Water, planning for winter begins in September.

This involves making sure sufficient resources are available to tackle higher levels of leakage caused by cold weather.

A few years ago the firm was heavily criticised for its record on leakage, but at the beginning of this year the Bradford-based firm was named as one of only two water companies in the UK - the other being Severn Trent - to reduce leakage in 2012 to 13 when compared to the previous year.

The harsh winter of 2011 led to the company falling short of its leakage target. “It was the worst winter we had seen in more than 20 years,” says the firm’s metering manager Tony O’ Shea.

Latest figures show leakage across Yorkshire at 281 megalitres (a megalitre being equal to one million litres) a day. The company’s target for the time of year is 286 ml/day. “It is a rolling target for the year,” says Tony. “Our actual position this year is very similar to how it was last year. We have roughly the same levels.”

The level beats the target, but, it is is still a significant volume of water, he says. ” Much is being done to further reduce this.”

Yorkshire Water’s end of year (March 31) target is 297ml/day, allowing for cold weather over the next three months and leakage increasing as a result.

The number of leaks increase in winter due to the lowering of the water temperature. “When water gets cold the cast iron pipes contract leaving space around them, causing them to pull out of joints,” explains Tony.

A significant proportion of leaks are associated with joints in the pipe network. “We do get some failure of pipes that break but problems are usually associated with the joints.”

Yorkshire Water’s network - which has 30,000km of customers’ pipes connected to it - has around 17million joints. The majority of pipes are cast iron, which are more susceptible to cracks due to cold than other types. Many are aged between 30 and 40 years but can be as old as 90. A rolling programme of replacement has already benefited many areas of Bradford.

A state-of-the art monitoring system works in tandem with age-old detection methods to tackle leaks as quickly and efficiently as possible, with minimum disruption.

“Data from across the network comes in more regularly than it used to,” says Tony. “It is updated every 30 minutes through telemetry, a highly automated communications process by which measurements are made and data collected at remote or inaccessible points and transmitted elsewhere for monitoring.

“Alarms alert staff to situations that are not normal. An overnight process allows us to identify any discrepancies,” says Tony.

Problems can be narrowed down to a group of pipes. “We locate and fix 99 per cent of these before the customer becomes aware of them,” he says.“The others are leaks that happen fairly dramatically. Customers see them, but often we can get to them and fix them before they are inconvenienced.”

High tech methods of detection include leak noise-detection devices which can pick up sounds caused by small cracks or holes and gas injection. “We inject hydrogen gas and because this is lighter than air it finds its way to the leak or gap and we use a sniffer device to locate it,” explains Tony.

There is still a place for rudimentary testing methods. “Listening sticks continue to be widely used. “Every one of our leakage inspectors has one.” Across the region there are 104 leakage inspectors, supported by 118 field technicians.

“If conditions worsened we would deploy extra staff and if the weather became very extreme we would contract additional repair teams,” says Tony.“There is always another challenge around the corner, but our reporting system and analysis is better than it has ever been,” he adds.

Customers are encouraged to help themselves to reduce the risk of burst pipes in their own supply system by taking preventative measures such as lagging and keeping central heating ticking over. These are outlined on Yorkshire Water’s website, where information is also given as to how to deal with frozen pipes.

Figures from the Association of British Insurers show that a staggering 374,000 claims for damage to homes by frozen pipes were made across the country last year alone, and many people did not realise that they were responsible for pipes on their own property.

*yorkshirewater.com