Water complaints drop by 12% in England and Wales
Complaints from customers to water companies in England and Wales fell by 12% last year, the fourth annual decline in a row.
There were 163,027 written complaints - by letter, fax or email - in the 12 months to the end of March, the Consumer Council for Water (CCW) said.
However, there was not a uniform dip across the country.
Seven of the 23 water and sewerage companies reported a rise in consumer gripes compared with the previous year.
"While most companies have made clear efforts to improve their service, there are still some that need to take action to address their high complaint levels," said Tony Smith, the watchdog's chief executive.
"Water is currently a monopoly industry, but companies must not rest on their laurels and assume that they can get away with delivering poor service. Today's consumer expects more than that and we will continue to support them in demanding a consistently good level of service across the country."
South East Water was ranked as the worst performing company when complaints were compared to its customer base.
It received 147 complaints per 10,000 customers, a rise of 59% on the previous year.
Steve George, customer services director at South East Water, said: "Our responses to customer inquiries were delayed in the early part of last year, leading to higher numbers of customers contacting us, which can often then become classified as a complaint.
"We are pleased that our service has returned to the improving trends we had been working hard to deliver. We can reassure our customers of the efforts we are making to fix their issues, quickly and first time."
Other companies in the area - Thames Water and Southern Water - also saw a rise in complaints.
The biggest improvement was at Dwr Cymru Welsh Water, which saw a 58% drop in complaints. Wessex Water saw a reduction of 40%, while United Utilities witnessed a dip of 31%.
Complaints across England and Wales remained higher than the lowest level on record, although not all of these complaints proved to be justified. On average, there were 53 complaints per 10,000 customers.
Typically, customers initially complain to their local water company, before about one in 10 take their dispute to the CCW. The watchdog said it secured compensation and bill reductions of £2.3m during the year.