A bypass will be built on farmland to ease congestion on the north west's busiest A road.

Highways Agency chiefs have unveiled the final proposed route for a new dual carriageway connecting the M56 and M6, which will help drivers get between Greater Manchester and Cheshire more easily.

The £130m project is being carried out to ease major traffic jams on the A556 Mere road – which has been named Britain's most congested rush-hour route.

Nearly two-fifths of the 50,000 vehicles that use it each day are lorries. Five people have died on the road and there have been 200 crashes in recent years.

The scheme will take traffic away from luxury homes in Mere and Bucklow Hill.

Mohammed Swapan, Highways Agency project manager, said: “This announcement is a step forward to delivering these vital improvements which will help reduce congestion, make journey times more reliable and increase road safety for the thousands of drivers who use the A556 every day.”

Two alternative bypass routes were drawn up for the A556 after new motorway plans were axed by then transport secretary Alistair Darling in 2003.

The government announced a preferred route for the new route following a public consultation in 2008.

Now the agency has completed the jigsaw by unveiling an amended option for the final one-third of a mile between Mere Hall and the M6 at Over Tabley.

The proposals had altered after plans to widen the M6 were shelved. A consultation took place between September and December last year.

The final section, which takes the route west of Mere Hall through open farmland and to the west of Tabley Parish Hall, completes the overall outline of the road.

Bosses at the agency say there will be further consultations when more detailed proposals are drawn up. Work could start in 2013 and the route could open by 2015.

The A556 is the only non-motorway section of the strategic road network linking north Cheshire and southern Greater Manchester with the West Midlands and the South.

The existing road will be closed south of Old Hall Lane, but commuters on that road will be able to access the new route at a new junction with the A50 north-west of Mere.

An environmental statement will now be drawn up on the proposals.