Consumers in Wales felt 'badly let down' after thousands of homes were left without water following the Beast from the East, according to the Consumer Council for Water.
They found that a lack of emergency water supplies and poor communication from some water companies made life 'needlessly more difficult' for those left without water.
More than 20,000 customers across England and Wales were without water for four hours or longer. The study also found that three quarters of households and businesses did not receive any alternative emergency supplies of water.
The water watchdog is now calling for companies to act on its findings and improve communication with customers.
Welsh Water said the scale of the Beast from the East was 'unprecedented'