The proposals, announced at the party's annual conference in Brighton, included bringing forward planned Government spending rises on infrastructure and forcing waster companies to upgrade drainage systems.
Other measures include plans to limit building on flood risk areas and ensure that infrastructure for new developments is able to cope with increased flooding in the future.
Liberal Democrat environment spokesperson Martin Horwood said: “With the prospect of greater flooding in the future due to climate change, the Government must start taking flood management seriously.
“Events this summer demonstrated the sheer destructive power that can be wrought by flood water. Instead of cutting the Environment Agency’s budget, ministers should be investing more in flood defences, starting now.
“We must review the continuing development on flood risk areas, which puts many families in jeopardy. Where developments do take place, much more forethought must go into keeping homes dry.”
Following the summer floods that devastated central and northern England the Government announced that the flood defence budget for England and Wales would be increased to £800M by 2010-2011.
However, the Liberal Democrats say this leaves no guarantee for the intervening years and propose an immediate increase.
The party also proposes a statutory duty on the private water companies to review and upgrade drainage in line with the increased needs due to climate change, as well as to maintain drainage systems properly and make pumping stations proof against flooding.