M3 (Hansard, 27 February 1990)

§ Mr. Parkinson

My right hon. Friend the Secretary of State for the Environment and I have decided that the published proposals for the final section of the M3 around Winchester to replace the heavily congested bypass should go ahead.

The decision follows two lengthy public inquiries conducted by independent inspectors nominated by the Lord Chancellor. Both inspectors considered the relative merits of the published scheme for a cutting across Twyford down and several alternative routes put forward by objectors, including those for routing the motorway in twin-bored tunnels under the down and for building the motorway on the line of the existing bypass.

Because of the adverse effects on the Winchester water meadows and residential areas of the city, the inspectors recommended that western routes following the line of the existing bypass should not be built. They endorsed the Department's novel proposals for removing the bypass completely and restoring the area to link the historic and recreational areas of the water meadows and St. Catherine's hill.

The inspectors were impressed by the alternatives for twin-bored tunnels under Twyford down. We too were attracted by the concept of tunnels which would have reduced the amount of land required from the east Hampshire area of outstanding natural beauty, the St. Catherine's hill site of special scientific interest and the two scheduled ancient monuments on Twyford down.

However, we agree with the inspectors that twin-bored tunnels would not be without environmental problems. The two tunnels, each large enough to take three lanes of motorway traffic and a hard shoulder, with portals on either side of Twyford down, would be prominent features in the area of outstanding natural beauty and emphasised by the necessary lighting. There would be considerable problems in disposing of vast quantities of surplus rock, and a tunnel scheme would be less efficient for local traffic distribution.

Such tunnels would be at the forefront of tunnelling technology, and the time necessary to design and construct them would delay seriously the completion of this much-needed section of motorway. Also, because of the innovative nature of the tunnels, the estimated costs of such a scheme varied widely at the inquiries. The 1987–88 inspector concluded that a tunnel solution would cost about £92 million more than the published scheme.

Both the inspectors concluded, and we agreed with them, that the advantages of a tunnel scheme would not 140W outweigh the substantial additional costs and the extensive delay in completing the M3. We have decided, in accordance with the recommendation of the two independent inquiry inspectors, that the published proposals are the right solution to the urgent need to replace the heavily congested Winchester bypass which has been the subject of considerable debate for almost 20 years.