According to figures released today (January 14) the cold December led to nearly double the number of customer calls.

The firm’s chief operating officer, Steve Shine, said the number of calls were ‘astonishing’ as 103,000 were handled – up 78% on the 58,000 received in December 2009.

Around 80,000 of these calls were about either burst supply mains on the company’s network or frozen pipes on customers’ properties.

Sustained freezing temperatures since November has led to a near fourfold increase in bursts and leaks on Thames Water’s 20,000-mile network of water mains.

Mr Shine said: “The number of December calls to our customer service team directly reflects the operational challenge we face in sustained cold weather.

“Water in our reservoirs and pipes cooled down to below 1.5C (degrees Celsius) at the end of December, the coldest we have ever recorded at that time of year, way under the average of 7C.

“When water drops below 5C our pipes, especially the century-old cast-iron ones, contract and break more.

“But when the weather warms up, which it has done since the New Year, our problems don’t disappear.

“That’s because water in our reservoirs, which are very deep and wide, takes several weeks to level with air temperature.”

Luke Walsh

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