Britain deployed army personnel, lifeboats and a military helicopter on Sunday to rescue people trapped by floods that have deluged parts of the country in the wake of Storm Desmond.

Thousands of homes and business were affected by the heavy rains and strong winds that battered Britain over the weekend, with one death reported in London after a man was blown into the path of a bus, police said.

Hardest hit were Cumbria and other parts of northwest England, where towns and villages were flooded with water that reached waist height in some places.

"The thoughts of the whole country will be with the people in Cumbria and the northwest who have suffered so terribly from the devastating storms this weekend," Prime Minister David Cameron said in a statement.

"The government is doing everything it can to help those who have seen their homes flooded -- and to try and prevent further damage."

Some residents trudged through the waters carrying their possessions, including pets, while others were helped onto dinghies and even a canoe crewed by volunteers.

Many elderly flood victims moved up to the second floor of their homes and leaned out of their windows as they waited for help.

In Cumbria, the torrents caused the historic Pooley Bridge to collapse, and police said two others had also been "washed away".

Tens of thousands of homes in northern England could be without power for days after flooding at an electricity substation, the BBC reported.

By Sunday evening Britain's Environment Agency website still carried flood warnings for more than 130 areas, mostly in the northwest, including 46 warnings of "severe" floods that could pose a threat to life.

"There remains a risk of further flooding in some areas and the Environment Agency continues to warn communities in northern England to be prepared today and tomorrow," said Environment Secretary Elizabeth Truss.

She said data from a rain gauge in Honister, Cumbria, suggested a record amount of rain had fallen in the area over the 24-hour period between Friday and Saturday evening.

Cameron is expected to chair a meeting of the government's emergency COBRA committee on Monday to coordinate a response to the crisis.

Desmond is the fourth named storm to hit Britain in recent months.

Around one in six properties in England are at risk of flooding, the government says, and experts say the risk is growing in correlation with climate change.