Utilities firm must submit quarterly reports to watchdog detailing its progress

Thames Water has blamed the beast from the east and last summer’s heatwave after recording the highest number of water company complaints last year.

Britain’s largest water firm topped the list of complaints in the last financial year, according to the Consumer Council for Water (CCWater).

Thames recorded the most complaints per 10,000 customers between April 2018 and March 2019, up 10% from the previous 12 months. As one of the worst performers it will be forced to submit quarterly reports to CCWater detailing its progress.

The company said it had struggled to repair the “unprecedented” damage caused by the cold snap in early 2018 and meet the spike in demand during last summer’s heatwave.

Other companies in England and Wales taken to task by CCWater include Hafren Dyfrdwy, Northumbrian Water and its sister company, Essex and Suffolk Water.

Tony Smith, the chief executive of CCWater, said: “Far too many customers are having to waste their time and suffer the frustration of disputing unclear or inaccurate bills.

“In the autumn we’ll be bringing the whole industry together to try and improve the standards of billing, as well as demanding a significant fall in the complaints made to the four poor performers named in our report.”

The four worst performers were an exception in an industry where customer complaints are falling, CCWater said

Kelly Macfarlane, Thames’s customer experience director, said it regretted the impact of its “unacceptable” customer service.

She said the supplier had already cut its complaints by 10% since April after giving more than 2,000 people specialised training and investing in a new website and billing system.

In a boardroom showdown earlier this year, Thames sacked its chief executive, Steve Robertson after he failed to turn the company around.

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Thames was given a dressing down by the regulator for not doing enough to tackle the leaks in its water network, which services 15 million people across London and the Thames Valley.

Claire Sharp, a director at Northumbrian Water, said the figures were disappointing but it was confident the results reflected “a very temporary setback” while it invests in better customer service.

A spokesman for Hafren Dyfrdwy, the Welsh division of Severn Trent created in July 2018, said the company was aware there had been some issues for customers and apologised to everyone affected. “We’re confident they’ll see a much stronger performance now and in years to come,” the company said.