DORSET'S busiest arterial road is failing and needs £26 million spent on it to bring it up to standard.

Traffic chaos is on the cards for six months while work is carried out on Bournemouth's A338 Spur Road from January 2009.

And narrow Matchams Lane will provide the alternative carriageways during the work.

The Spur Road has been in place for 40 years, replacing the old A338 - now B3347 - between the A31 at Ringwood and Christchurch.

And it is worn out, says Dorset County Council. Cracks are appearing, the smooth surface is breaking up and costly repairs are constantly required.

Funding for the major project should be known by March next year.

Motorists had to endure lengthy tailbacks and delays for about three months earlier this year when, from February, a 40mph limit and contraflow working was put in place for partial resurfacing and drainage repairs.

Each closure brings with it delays, frustration and the increased risk of accidents.

Last winter, warning lights began to flash at Dorchester when the county council realised major road reconstruction was needed to keep the Spur Road up to standard.

Road engineers have examined the situation and tomorrow, the road's condition and budget strategy is to be discussed by the community overview committee.

A report by Andy Ackerman, head of highways client services, says current levels of expenditure on structural maintenance of Dorset's roads are in decline and require an injection of capital.

Just £5.22 million is in the budget during the current year for highways maintenance, the lowest in the South West. Combined with high inflation rates in construction costs, it amounts to a 22 per cent reduction in budget.

To bring more stability, a bid has been made to the county's asset management group for more money.

To exacerbate the situation the "A338 road construction is failing and poses a significant problem for Dorset County Council and for the South East Dorset conurbation", say committee papers.

The dual carriageway requires reconstruction, at current costs up to £26 million, and this is not affordable," the report adds.

If the bid for regional funding is approved, the county council will have to provide 10 per cent (£2.6m) of the cost.

And the report warns that delay will lead to repeat maintenance work, traffic disruption, increased costs to business, increased risk to drivers and the potential for claims against the council.