Winchester and the alternative to the M3 - Trust Annual Report 1976
The existing A33 would be improved by the widening of carriageways to modern standards where necessary, and the easing of bends to a design speed of 60mph. New grade separated interchanges designed to normal standards for this type of road are provided at Kingsworthy, Easton Lane and Hockley, while the slip roads at the Petersfield road junction are extended and visibility improved.
Hard shoulders are provided sufficiently wide to take a third lane in the future, should traffic volumes rise to require this. In that event intermittent hard shoulders would then be provided except on the Itchen crossing and around St Catherine's Hill.
It is not intended to widen the Spitfire Cutting until such time as traffic volumes may require it. In that event it would be increased on the eastern side to become dual three lane.
Noise barriers in the form of earth mounds or acoustic fences are proposed at Kingsworthy, Winnall, St Catherine's Hill and at certain places at Hockley and Compton. These will be similar to the DoE's mounds, and calculations show that conditions at Kingsworthy, including the school, and at Winnall will be quite as satisfactory as in the DoE proposals. With care during construction, most of the existing trees along the canal can be retained. Any cutting into the base of St Catherine's Hill is well below the line of archaeological interest, and will be covered with vegetation. Calculations show that sound from the road will be marginally less in the alternative scheme than in the DoE scheme, and at a distance considerably less. This is because attenuation due to distance favours the alternative, and reflection from the base of the hill is avoided by careful design.
The canal is untouched, the railway embankment above carries the additional roadworks and acoustic wall. A diversion channel for the navigation near the Hockley interchange can be designed to allow continued use of the navigation if so desired.
Gamier Road is stopped off at Tunbridge, which is untouched, but is linked by a new section across council owned depot land, to Bar End.
The Hockley slip roads include a small roundabout on the A333, which prevents traffic taking a direct and fast route towards Twyford.
The Shawford-Compton section crosses the valley under the railway making less impact than the M3 scheme, and slip roads using the old railway bridge avoid the easy access into Compton as at present. Shawford Common is affected to a very minor degree. Trees are retained wherever possible.
The alternative puts forward a flexible scheme capable of realisation by instalments, and would meet the DoE forecasts should they ever materialise. It is a "fitted" road avoiding the disruption caused by the M3 scheme, While respecting the special environmental qualities of the historic city.