Householders in the South are to be hit with the largest increase in water bills this year.
Thames Water will see the biggest percentage rise in water and sewerage bills with an increase of 5.5%, leaving households with an average bill of #354, according to the industry regulator Ofwat.
Southern Water bills will rise by 5.3% with an average payment of #449 while households supplied by Wessex Water will face an average bill of £478 - an increase of 4.9%.
Last week Ofwat announced proposals to change the way it regulates the water and sewerage sectors to ensure more sustainable water use.
The regulator also welcomed a report on the Draft Water Bill, which has identified potential benefits of £2 billion by changing the way water is managed.
Ms Finn said: "There are longer-term challenges if we are to continue to keep bills down.
"Unpredictable rainfall and population growth in areas where water is already stretched means we need to get better at managing and sharing our water. If we don't, customers will lose out.
"Our proposed changes, combined with recommendations in the Draft Water Bill, mean there is a total of £3 billion worth of benefit on the table for customers if we make the right changes.
"We cannot afford to stand still if our water supplies are to remain both affordable and sustainable in the decades to come."