Storm damage is now totalling more than £21 million and it may increase after further storm damage during the weekend.
The cost of immediate repairs will be £3.5 million with long term work costing £17.8 million, according to Cornwall Council.
Both these figures are set to rise in the coming days and weeks as detailed inspections of damaged areas are carried out by structural engineers and Cornwall is affected by further periods of strong winds and heavy rain.
Cornwall Council has welcomed the commitment from the Prime Minister to do whatever it takes to help communities in Cornwall which have been badly affected by the recent storms.
The Government has also announced changes to the Bellwin scheme which reimburses local authorities for the costs of dealing with emergencies and the Council is now seeking an urgent meeting with Ministers to discuss the practicalities of what Cornwall needs.
Cornwall is one of the areas which has been worst affected by the recent severe weather, with significant structural damage to buildings, harbours and flood defences.
Cornwall Council Leader John Pollard had already called on the Government to provide more financial support for Cornwall and he is welcoming both the offer of support from David Cameron and the changes to the Bellwin scheme.
“We have long been highlighting the unfairness of the current threshold to large unitary authorities like Cornwall and have been lobbying strongly for a change in the rules,” said Mr Pollard.
“I am pleased that the Government has now recognised this and we are asking for an urgent meeting with Ministers to clarify just what this will mean.
“We have also welcomed the announcement of the additional £100 million for flood works and are looking forward to ensuring that Cornwall gets the funds it needs to repair the damage done."
Under the current Bellwin scheme local councils can apply to be reimbursed for a proportion of the costs incurred from the immediate actions they have taken in connection with a disaster or emergency.
There are, however, strict criteria for applying for funding which are based on a percentage of the council’s overall budget.
This means that a large unitary council like Cornwall has to spend at least £1.4million before it can apply for financial support.
The level of financial support is also currently limited to 85 percent of the threshold – leaving councils to meet the remaining 15 percent costs from their own budgets.
Communities Minister Brandon Lewis has now announced that the Bellwin grant will be paid at 100 percent above the threshold and the eligible spending period will be extended until the end of March.
The Minister also announced that the threshold for applying for funding would be reduced for all County Councils and Unitary Authorities although there is no detail on the new level.