Southeastern Water said in a statement: “While we acknowledge that the climate is changing, this year we have seen an exceptional combination of extreme weather events that have had a significant impact on our business operations and financial performance.
“While we have made every effort to meet our stringent performance targets and stringent environmental commitments that go beyond our statutory obligations, extreme weather events had a significant impact on our performance last year.”
The company said it had dealt with the driest conditions in Kent since records began in 1836, and the lowest rainfall in Sussex since 1911.
Last month, South East Water imposed a hose pipe ban on customers.
Chief executive David Hinton said the company had little choice after drinking water demand hit “record levels” in June, similar to last year’s drought.
More than 4,000 customers in Rotherfield, Mayfield, Tunbridge Wells, Crowborough and Wadhurst were without water in June.
Meanwhile, some families in Kent and Sussex faced similar problems in December due to cold weather, which the company said caused pipes to burst.