The exceptional change in Britain's weather from droughts to flooding is being described as one of the most dramatic transformations in decades.
The analysis from the Centre for Ecology and Hydrology comes as the Met Office confirmed 2012 was the second wettest year since records began.
Professor Alan Jenkins told Sky News the shift from dry to wet conditions in the past 10 months has been remarkable.
"Back in March we were looking at a very dry situation and we were heading into one of the biggest droughts that the south east of England has ever experienced.
"So the wet year of 2012 ... will be based really on nine very wet months rather than 12, so you can imagine that's a lot of rain."
While water companies last summer imposed hosepipe bans on 20 million customers, a very wet December has caused widespread flooding.
But the flood waters are also a sign that our natural water storage underground is full and that any more rain water will go to waste.
With many reservoirs also now topped up, this has led to calls for more storage areas to be built to harvest rainfall more efficiently and stop a repeat of last year's hosepipe bans.
Michael Norton from the Institute of Civil Engineers said: "What is becoming obvious is that we're not storing enough of water to be more resilient during the drought periods, which probably means we all need to be prepared to pay a little more for our water."
Last year the Government organised a drought summit to look at what lessons could be learnt.
Speaking to Sky News, Floods Minister Owen Paterson said plans are being formulated to avoid water shortages in the future.
"That's one of the things we're looking at in the water bill, to see how we conserve water.
"I'm personally very keen on holding more water back in reservoirs and I think that's an issue many people agree on, people are uncomfortable with the amount of abstraction going on, I think there is a case for building more reservoirs."
The Environment Agency has already predicted there will not be any need for hosepipe bans this year.
Recent rainfall has meant south east England has enough water to get through two dry winters without a drought, but other areas including the North West and Wales are more vulnerable.
The unpredictability of Britain's weather means we will need to be better prepared to keep supplies topped up in the future.