I came across this site today whilst looking for Bidston Airfield.http://www.iht.org/motorway/page1.htm
Found some nice articles on the M53 and M56. I vagely remember the 56 extension.(http://www.iht.org/motorway/m56haplea.htm
"In the 1960's, Vauxhall Motors decided to build a car factory at Hooton, Ellesmere Port, on the site of a disused airfield. However, the existing road access was totally inadequate.
A new road network was required within the immediate area, to serve the development. Not only was it essential for the supply of raw materials, and as a reasonable means of access for employees, but it was required also for the delivery of finished vehicles to markets in all parts of the country and abroad.
The site was close to Ellesmere Port itself, at the western end of the Manchester Ship Canal, and near to the Docks at Birkenhead and Liverpool.
In particular, access was needed to the A41, the major road between Chester and Birkenhead.
In view of the employment which the factory would bring to the area, the Cheshire County Council was keen to assist in the development. Following negotiations with the Company it was agreed that a new dual two-lane carriageway road would be constructed from a junction with the A41 at Hooton, and a junction with the A5032 immediately north of Ellesmere Port, both of which would be grade separated. The latter would link directly into the site of the new factory and its cost would be met by the Company.
Both the factory and the 2½ mile long road, known initially as the 'Hooton Industrial Road', were built concurrently by the same Contractor.
Although primarily serving the needs of the factory when completed in 1968, it soon became apparent that there was an expanding need for even better facilities. It was decided, therefore, to extend the road southwards, through Ellesmere Port for a further 2½ miles, as far as the A5117 and to provide grade separated junctions. On completion of this section, in the summer of 1975, and upgrading to a dual two-lane carriageway standard, the whole length was designated as the M531, the first 'county motorway' in Cheshire.
Meanwhile, in 1965, G Maunsell and Partners, the firm of Consulting Engineers, was appointed by the Ministry of Transport to carry out a location study for a new route serving the Wirral Peninsula generally. It was to commence from the southern end of the second Mersey Tunnel (Wallasey-Liverpool), at Bidston, and terminate in the Hooton-Sutton area."
"The design of the Woodchurch Interchange was unusual and, at that time, the only one of its type in the country. It is, in effect, a three-level interchange fitted into a two-level site, by having an elongated roundabout with rising gradients. Features controlling the design were the limited headroom under, and in close proximity to, a railway; the Fender River flood water levels; a nearby block of flats; and the limited availability of land due to new development."