The Flood Re scheme subsidises insurance premiums for homes on flood plains through a £180m tax on everyone else’s home insurance.
However, the BBC reports that Committee on Climate Change (CCC) says the costs of the scheme are three times greater than its benefits.
The Department for Environment, Food and Rural Affairs said Flood Re made insurance available and affordable.
The CCC, an independent body set up to advise the government, is calling for the tax on everyone’s premiums to be reduced.
It says that in addition to this, cash should help prevent flood damage rather than be paid to people to clean up after a flood, it says.
Around half a million homes will have their insurance capped under the plan, but the committee says the insurance industry calculates that only 200,000 of these recipients would genuinely struggle to afford insurance without the support.
It says the cost of Flood Re breaks normal government spending rules because it offers negative value for money.
The chair of the CCC’s adaptation sub-committee, Sir John Krebs, told BBC News: “Flood Re is set to subsidise many hundreds of thousands of households more than the estimated number that might struggle to afford cover in the free market.
“This makes Flood Re needlessly expensive.Managing flood risk will always be the best way of securing affordable insurance in the long term.
“A transition should be achieved by helping high-risk homes become more resilient.
“There is a risk that Flood Re will be counter-productive to the long-term management of flood risk in the UK, as it largely removes the financial incentive for households to take steps to avoid being flooded.
“As a consequence, the industry levy funding the scheme could spiral.”
Flood Re was set up in June 2013 by ministers in collaboration with the Association of British Insurers (ABI).
The CCC says Flood Re should be building awareness because many householders in high-risk homes have no idea they are living on a flood plain.
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