The leading lobby group for boaters on the Broads has accused the waterways' governing body of a 'smash and grab raid' on boat toll money.

Although money raised through private boat licence fees is ring-fenced by law to be spent on maintaining the waterways and patrolling them, the Broads Authority is proposing to increase the amount of the tolls budget used to meet its general overheads such as management and administration costs by �250,000.

Broads Authority chief executive John Packman told the Norfolk and Suffolk Boating Association's (NSBA) annual meeting that, up to now, the authority's national park grant had paid for a large proportion of its administrative and support services.

But in light of a projected 30pc cut in government funding, and with the authority already having to make massive savings, including a significant reduction in its staff, it had been recognised that navigation expenditure would need to bear a fairer share of these costs.

The controversial proposals will be discussed at a meeting of the authority's navigation committee on Thursday.

NSBA chairman Mark Wells said he could see no justification for any increased support from the navigation budget towards overheads from its existing level of �440,000 that had previously been accepted by the authority.

He warned: 'It puts progress on dredging at risk and toll payers have been paying high toll increases for years so the 30-year backlog in dredging can be tackled.'

Mr Wells said the NSBA members who had attended the meeting at the Assembly Rooms in Norwich had struggled to follow Dr Packman's reasoning.

He said: 'It seems to me like a smash and grab raid to featherbed the authority rather than face up to the cuts it should be making. At a time when the authority will be getting smaller and doing less, it is taking money that should be 100pc protected.'

Mr Wells said the association's view was that any increase in toll contributions to overheads would be contrary to the 2007 Broads Act and they would be taking appropriate advice.

Peter Horsefield, chairman of the Broads Society, echoed Mr Wells' concerns and said the issue would be discussed at their next meeting.

He said in a slimmed down Broads Authority, overheads ought to be going down, so it was puzzling why the navigation budget was being asked to contribute more to the general pot.

Dr Packman highlighted the fact that navigation would account for a higher proportion of the work of the future slimmed down authority and that was a further justification for increasing its contribution to general costs.

He said: 'A group of five members, three of whom are boat owners, have devised what they consider to be a fair and transparent system of allocating shared costs. This is in line with the legal requirement that income from boats has to be spent on navigation, and the agreement we have with the Royal Yachting Association which sets out how expenditure is accounted for.

'I am surprised that the NSBA has taken such a hostile reaction to these proposals. As always, the members of the Broads Authority try to strike a middle line on these matters which is fair to all interests.'

He gave a firm pledge that the authority would continue with its current plan to remove 50,000 cubic metres of sediment from the navigation area every year over the coming five years.

Dr Packman also countered NSBA criticism of the authority's decision to combine navigation and conservation ranger operations, arguing that it would bring greater flexibility and cost savings in equipment and vehicles.