Two people were found dead in the west of England, raising to at least eight the number of people to have died as a result of record rainfall.
The pair were believed to have been overcome by fumes from a petrol-powered pump as they tried to remove water from the basement of a rugby club.
Up to 350,000 people in central parts of the country remain without running water after the floods damaged power sub-stations and knocked out sewage systems.
In the past two months, Britain has experienced the highest rainfall since records began in 1766, leading rivers to burst their banks and forcing up to 10,000 people from their homes.
Insurers have said the combined cost of the June and July floods could top £3bn. There is also expected to be a heavy impact on agriculture, with farmers warning that any more rain could affect harvests.
The army is distributing 3m bottles of water a day to people who no longer have access to drinking water.
The deaths follow the disappearance of a teenager from a severely flooded town last Friday and at least six deaths from widespread flooding across northern England in mid-June.
Meanwhile, the flooding has led to fears of bacterial infection as flood waters recede.
The Director of Public Health for Gloucestershire says sanitation is an increasing issue.
Emergency workers need thousands more portable toilets and there are not enough water tankers to distribute water.
There are now warnings of infection from bacteria such as E.coli and salmonella as filthy flood waters recede.
