WALES’ largest water company has been told to improve its performance by the Consumer Council for Water (CCWater) after complaints from its customers more than doubled in the space of a year.

Problems caused by more rigorous debt collection, a new billing system and poor communication with some customers, sparked a 115 per cent rise in written complaints to Dwr Cymru Welsh Water during 2015/16 – the biggest increase of any water company across England and Wales.

But there was good news for customers of Dee Valley Water, which saw complaints fall for a fifth successive year, this time by nearly 13 per cent. Severn Trent, which serves a small number of customers in Wales, emerged as one of the industry’s best performers with complaints having fallen almost 28 per cent in the past year.

Tom Taylor, Chair of the Consumer Council for Water’s Wales Committee, said: “We are disappointed the good progress Dwr Cymru Welsh Water had made in recent years has been undermined by such a sharp rise in complaints.”

“The company has identified the steps it needs to take to put things right with its internal systems and communication with customers, but we will be watching closely to make sure these changes deliver significant improvements.”

Across the whole water industry in England and Wales written customer complaints fell marginally by 0.5 per cent last year, down from 106,693 to 106,196.

The number of telephone calls customers had to make to water companies to resolve issues also fell broadly in line with written complaints.

But ten water companies, including Dwr Cymru Welsh Water, bucked the overall industry trend and reported a rise in complaints.

CCWater has asked Dwr Cymru Welsh Water to provide it with a report by the end of October 2016 explaining what progress it has made in reducing contact from customers.