WOODLAND and meadows will suffer 'very substantial damage' if Weymouth's £84 million relief road is built, a public inquiry was told.

Opponents and supporters gathered at The Heights Hotel, Portland, yesterday at the start of a three-week inquiry into compulsory purchase and side road orders for the scheme.

Work on the relief road - which will bypass Broadwey, Upwey and Dorchester Road by linking Manor Roundabout to the A354 at Ridgeway Hill - is hoped to start in summer 2008 and be finished by Christmas 2010.

Dorset County Council says the scheme will make traffic flow smoothly on the A354 but groups such as Natural England, the Woodland Trust and the Campaign to Protect Rural England claim nature interests will be severely damaged by the road.

Inspector Alan Gray opened the inquiry and said he had already visited most land affected by the proposed orders.

Andrew Tait presented the county council's case and said the A354 was 'inadequate' with drivers frustrated by unreliable journey times leading to a perception that Weymouth and Portland was difficult to access.

He said the relief road would provide a reliable and attractive route for traffic and, while it would require land in the Lorton Site of Special Scientific Interest (SSSI), ecological and other measures had minimised the impact of the road.

He added that there was 'a compelling case' for the orders which were backed by the authority, two district councils, local MPs, businesses, bus companies and the South West of England Regional Assembly.

But Graham Machin, for Natural England, said damage to an Area of Outstanding Natural Beauty and an SSSI would be 'very substantial' and should only be allowed in 'exceptional circumstances'.

He said that the county council had to show there was 'an overriding need', and they had failed to do so.

He added: "No need for the scheme has been identified such as to justify the severe damage it will cause."

Charlie Hopkins, for the Woodland Trust and the CPRE, said the road would cause 'irreversible damage', the scheme's traffic case was weak and other less damaging non-road building alternatives were available.

He added: "There is a general acceptance on all sides that if the road were to be built significant damage would be done to Dorset's natural environment."

He also highlighted the destruction of part of Two Mile Coppice and significant damage to the Lorton Meadows Nature Reserve and said the scheme went against local, regional and national transport policies.

An overview of proposals was then presented by Paul Willis to start county council evidence, who said the A354's poor capacity and reliability hit the local economy and provided inadequate access to employment and development opportunities.

He said there was 'a compelling case' for the scheme which would reduce congestion, improve reliability, meet transport needs, assist economic growth and help measures to support public transport.

Transport expert Craig Drennan gave a traffic and economic evaluation of the scheme which he said would relieve A354 and A353 traffic, reduce Weymouth-Dorchester journey times, cut road casualties, benefit business and considerably improve the footpath and cycleway network.

The inquiry continues.