As of Wednesday night, 10,000 properties continued to have no water supply.
Lynn Parker, Ofwat’s senior director for enforcement, said: “The last six weeks have been miserable for businesses and households across Kent and Sussex with repeated supply problems.
“We know that this has had a huge impact on all parts of daily life and hurt businesses, particularly in the run up to the festive period.
“That is why we need to investigate and to determine whether the company has breached its licence condition.”
