Marham's importance to Norfolk's economy could be far greater than previously estimated, it emerged last night.

Council economists reckoned the base was worth �120m - looking at the salaries of military and civilian personnel who work at the base, almost 70pc of whom live in towns and villages across Norfolk.

But a draft report by specialist consultants, seen by the EDP, calculates its gross value to the county's economy at �208m.

Further studies will be carried out before a fuller version of the Economic Impact of Marham report is made public.

Experts will look at how much money earned at the base finds its way from wage packets to local businesses.

They will also consider the impact of the base's closure, if ministers decide to move the Tornado fleet and the planes' maintenance north of the border.

The draft warns that where bases are situated in rural areas 'it is unlikely that the ecomonies would have the same level of employment and expenditure in their economy through other means'.

Norfolk can speak from bitter experience on that score. The county is still reeling from the loss of RAF Coltishall and RAF Neatishead, in 2008.

Just a fifth of the jobs the bases provided have been replaced since their closure.

Marham is one of Norfolk's 10 largest employers, with 10pc of jobs in the west of the county depending on the base.

Nearly 70pc of staff and hundreds of civilian contractors live off the base, supporting the economy across the whole of Norfolk.

Salaries for military and civilian personnel average �35,000 and �20,000 respectively, with Marham providing a rare source of skilled and well-paid employment in an area where 15pc of the workforce have no qualifications.

Spin-off employment, through contracts awarded to Norfolk businesses, is believed to generate a further �15m a year and support 300 jobs in the county.

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