Report by ITV News Meridian's Charlotte Briere-Edney
Thames Water says it's doing everything it can to fix leaks, responsible for losing more than 600 million litres of water a day - that's almost a quarter of all the water it supplies.
In Oxfordshire, substantial leaks have been reported by residents - who say Thames Water are just not acting quickly enough.
The criticism comes as the Reading-based company warns it's planning to introduce a hosepipe ban 'in the coming weeks'.
Residents told ITV Meridian that Thames Water should fix leaks before imposing a hosepipe ban, with one saying the response from the company has been 'pathetic'.
Speaking to ITV Meridian, Cathryn Ross from Thames Water said: "We need it (hosepipe ban) because it's been unprecedentedly dry.
"We've had a hugely hot July, which has come after a dry spring and a dry winter. We've had less than 65% of the rainfall we would usually get, so our water resources are running very low.
"We're going to take a decision on the hosepipe ban next week, as we are legally required to consult before we introduce the ban, so we're looking at around two weeks before it comes in.
"We do understand people's concerns about leaks, and we know we absolutely need to do our bit. We are doing that - we are fixing more than 1100 leaks every week.
"Leakage will always be with us as we have 20,000 miles of pipes. But we do recognise, particularly with climate change and the shortage of water, we need to take leakage seriously.
"With climate change we are getting more water where we don't want or need it, and then having enough water when and where we do need it."