The group, which is battling to survive amid a funding crisis, has proposed increasing spending by £1.1billion and revealed another potential £1.9billion investment in its network as part of new business plans to regulator Ofwat.
The customer, known only as El, had been trying to resolve the issue with her water bill since March last year and had been in contact with Thames Water almost every day
In 2017, millions of litres of raw sewage flooded two rivers in the Gatwick region and investigators found nearly 1,400 dead fish. As a result, Thames Water has been fined £3.33 million.