Almost 8,000 homes and businesses were flooded in 2012, as the UK was battered by repeated heavy rain, storms and floods.
Defences protected almost 200,000 properties, but with spending on such measures falling at a time when floods are predicted to get worse with climate change, the government has come under fire for cutting the flooding budget.
England and Wales experienced 10 separate flooding events between April and December after widespread drought gave way to the wettest summer in a century, with unusually high rainfall totals and river levels around the country.
At the end of April, parts of Devon and Cornwall saw more than 24 hours of continuous rain, while in late June, Honister in Cumbria saw 200mm (eight inches) of rainfall in one day, the Environment Agency said.
In July the River Axe at Weycroft Bridge in Devon was 3.58m (11.7ft) high, its highest level on record, and in September the River Ouse in York reached its second highest recorded level, as the most intense September low pressure system for 30 years moved slowly across the UK.
Coastal flooding hit Weston-super-Mare in October and Cornwall in December.
Through the year, nearly 200,000 homes received a flood warning from the Environment Agency's free flood warning service, and the agency said 199,632 homes were protected from floods by defences.
But spending on flood defences fell in the last financial year, the first full year since the spending review, from £354 million on new projects in 2010/2011 to £259m in 2011/2012.
The amount spent on maintenance also fell, from £172m to £156m last year.
The devastation repeatedly wrought on the country prompted the Treasury to provide another £120m in November for defences over the next couple of years, focusing on places where they would have the greatest economic benefit.
But in the summer, the government's advisory body on adapting to climate change warned there was a funding gap of almost £1 billion opening up between what is needed to keep properties protected and what is being spent in the next few years.
Floods are likely to become more common as the climate changes and increases the chances of extreme weather, and the Environment Agency has warned it needs a year-on-year increase of £20m for flood defences on top of inflation to maintain the current level of protection.
But flood defence spending is 12% below what it was in the last spending review period, with a gap opening up of £860 million between what has been pledged for 2011-2015 and what is needed to keep the same number of properties protected.
Around 610,000 properties will be at significant risk of flooding by 2035 without action, four times more than if there was increased investment in flood defences and more careful planning of new housing in the flood plain, the climate advisers have warned.
Shadow environment secretary Mary Creagh said: "This year's floods have shown how short-sighted the government was to cut investment in flood defences by £95m a year, leaving homes and businesses unprotected.
"Flooding is the biggest threat the UK faces from climate change, yet even after a mini U-turn in the Autumn Statement the government will still be spending less on flood defences next year than in 2008.
"Every £1 invested in flood defences saves £8 later and provides much-needed construction work.
"What a shame ministers have wasted two years looking for shovel-ready infrastructure projects while 294 flood schemes have been postponed or cancelled."