The motorway is formed on embankment throughout, apart from one very small cutting, with the height maintained at 2 metres minimum above ground level. A total of 1,500,000 cu. m of fill, generally bunter sandstone, was imported, including the granular drainage blanket to the base of the embankments.

Immediately to the east and west of Goole - Thorne Road (A614) the route crosses the course of the old River Don and here recent alluvial deposits in the form of peat and soft organic clay of up to 7 metres thick were present. These included up to 4 metres of soft silty clay (warp) at the top. Because consolidation settlement of about 1.0 metre could be anticipated it was decided to surcharge this area under an advanced earthworks contract in order to obtain the majority of the settlement prior to constructing the motorway and diversion of the A614. This was successfully carried out using colliery waste from Moorends Tip near Thorne in a contract awarded to French and cost £354,509 and commenced in November 1972 and was completed in May 1973.

Of the eight bridges on the contract, all of which were founded on piles driven to the underlying sandstone, the most interesting was the Interchange bridges at Rawcliffe and the Viaduct over the Goole Canal and the Dutch River. There was also a railway bridge carrying the motorway over the Pontefract-Goole line.

Langham West, East and South Interchange Bridges. These three bridges are identical and carry connecting roads over the motorway. They are curved in plan and have four continuous spans of 35m, 40m, 40m and 35m, and are 14m wide. Each deck is a single box spine beam with cantilevers and consists of post-tensioned pre-cast reinforced concrete segmental units supported on reinforced concrete piers and skeleton abutments.

The method of construction was novel in that the units for each bridge, prior to stressing, were supported on a temporary embankment as "falsework". This method was adopted as the most economic means of overcoming the poor ground conditions and the then predicted settlement in the area. Each embankment was constructed well in advance of placing the units and was monitored regularly for settlement. The units were supported on reinforced concrete plinths with provision for jacking each unit to its correct position prior to making up the in situ joints between the units. Following post-tensioning the embankment "falsework" was removed. The units were manufactured by Faircloughs.

Langham Viaduct carries the M18 motorway and a connecting road over the Goole Canal and the Dutch River on and eight span simply supported structure. The spans are 18m, 30m, 5 at 25m and 18m and the deck varies in width from 42m to 52m. The decks consist of pre-cast pretensioned concrete 'M' beams with an in situ reinforced concrete slab. The 30m span has additionally transverse reinforced concrete diaphragms. The structure is supported at its ends on reinforced concrete skeleton abutments and in the intermediate positions on piers formed of reinforced concrete portal frames, two of the piers were founded in permanent cofferdams within the tidal river.