She revealed the watchdog’s helpline was receiving calls from disgruntled householders unable to get vital information from Severn Trent.

The council has previously criticised the company for the poor quality of its customer services.

Customers claim Severn Trent has left them in the dark about when normal supplies will resume.

More than 340,000 people face the prospect of two weeks without fresh water after the Mythe treatment works in Tewkesbury, which normally supplies 26million gallons a day, was engulfed by floods on Sunday.

There are concerns that Severn Trent did not do enough the protect the site.

Cheltenham MP Martin Horwood criticised Severn Trent after bowsers ran dry in the flood-struck neighbourhoods in his constituency.

He said: “Many organisations have come out of the crisis well – notably the emergency services, the military, local radio stations and many individual friends and neighbours who have looked out for the most vulnerable. But Severn Trent today looks like a weak link. The strong impression is that Severn Trent did not have well worked-out plans for how to source bowsers or where to deliver them in the event of a critical interruption to supply.

“I hope Severn Trent will now move heaven and earth to get Mythe pumping station back into service.”

Severn Trent defended its actions, claiming it had “pulled out all the stops”. A spokeswoman said: “We have drafted in as many people as we can and they have been working extra shifts to try to cope. We have an information line with recorded messages which is updated throughout the day and there is information on our website.”

The firm distributed four million bottles of water yesterday with plans for a further five million today.

In addition, 926 bowsers, each holding 2,500 litres, have been set up on streets.

The spokeswoman revealed there were finally plans to pump in extra water supplies, something critics said the firm should have done as soon as the crisis broke.

Last night emergency services were standing by in Bewdley, Worcs, amid fears that part of a waterlogged hillside would collapse and demolish six bungalows below it.

Residents were evacuated on Tuesday night. The bungalows stand between the Severn and the hill, known as Northwood Slip.

In Gloucester, the Red Cross spent yesterday distributing toiletries, sanitary items and bottled water by boat. Temporary defences set up to protect the town’s Walham electricity sub-station – which provides power for half a million homes – were holding firm.

A disaster fund set up for victims of the floods soared past £500,000 last night.

Money will primarily be given to local authorities in affected areas to help vulnerable people rebuild their lives, or to local charities chosen to undertake work on their behalf.

Margaret Lally, British Red Cross Director of UK Services, said: “The fund is needed because we know that in most communities there are vulnerable people who will need extra help to rebuild their lives after these devastating floods.”