People in Kent and Sussex asked to use water only for essentials after outages.
South East Water says demand has jumped owing to extreme heat but stops short of compulsory measures.
South East Water has asked members of the public to use water only for essential purposes after demand surged on Monday to 100m litres more than average.
After water outages for hundreds of homes across Kent and Sussex over the last three days during record temperatures, the company has asked customers to use water only for drinking, washing and cooking.
