Water for washing and flushing toilets could be in homes across Gloucestershire from next week.
People have been relying on bottled water for drinnking
Up to 350,000 people are still without mains water after a treatment centre at Mythe flooded on Sunday.
A spokesman for Severn Trent said the company expected to begin pumping water from the plant on Tuesday.
It could be a further two weeks before mains water is fully restored, meaning some residents could be without running water for three weeks.
Operations manager Fraser Pithie said: "When the output starts, it's not like the electricity coming back on. It will not be at everyone's house at that time, it will take a number of days longer to fill the system up.
"And when that water arrives at people's taps, it will be 'do not drink'. It will be for sanitation."
It also emerged on Friday that five 18,000 litre water tankers are being taken to locations around the county for residents to collect water from and use for sanitation, on top of collections from bowsers and bottled water deliveries.
Police have said that some bowsers have been targeted by vandals, with 10 confirmed instances of criminal damage.
But the Chief Constable of Gloucestershire Police said he was not aware of any arrests relating to attacks or interference with bowsers.
Officers have received several calls alleging tampering, with one confirmed report of someone urinating in one of the 900 bowsers.
Bowser water should not be drunk without being boiling first.
Dr Tim Brain, Gloucestershire's Chief Constable, added: "Despite the stories that are circulating, the numbers of crimes that we are recording are very few indeed, and in fact at the moment, crime is down across the county of Gloucestershire as a whole.
"However I would say it is important that everybody behaves responsibly, and with care towards their neighbours and the rest of their community. Please do not use water selfishly."
He said the bowsers would be refilled on average, two to three times a day.
"The six million litres that we are supplying the county with every day... is small in comparison with the 120 million litres that is the normal running supply to the county.
"We are quite clearly, however, surviving and indeed as a county going beyond surviving and beginning to cope extraordinarily well with this emergency."