In the early 2000’s, the British Department for Transport was faced with a growing demand for handling container shipping around London. A proposal by Dubai Port (DP) World was approved for the construction of a completely new port and logistic park at the former Shell Haven site on the northern shore of the Thames, some 40 km east of London.
Construction of the fully-automated London Gateway deepwater container port was a highly complex and large scale undertaking, carried out as a ‘design-and-build’ project in which Dredging International (hydraulic works) teamed up with Laing O'Rourke.
Design requirements included the reclamation of a port platform and logistic park with an annual capacity of 3,5 million TEU; a 2,7 km long quay wall for ULCS’s of 397 m long, a draught of 15,5 m, and a capacity of 14.500 TEU containers each.
Deepening of the Thames over a distance of 100 km, widening the navigation channel to 300 m and bringing it to a depth of minus 14,5 m to minus 16,5 m compared with the previous minus 10 m.
The construction resulted in very impressive figures: dredging volume amounted to 27 million m³; reclamation for the port platform required no less than 18 million m³; a total of 150,000 tonnes of armour rock layer was used as slope protection; and 46,000 m² of fibrous open asphalt mattresses (FOSA) were installed as scour protection. Since the project yields an excess of 3 million m³ of material, commercial partnerships have been concluded for the supply of important quantities of gravel to third parties. These deliveries were carried out by DEME’s marine aggregates company DEME Building Materials (DBM).
The material that was dredged from the Thames and from a deepwater maneuvering and berthing area, was used to reclaim 92 ha of land from the river, and to raise 80 ha of existing land for the port development and the platform construction.
Prior to the main reclamation works, cross bunds were constructed in order to reduce currents and to limit the outrun of fine material in the river for environmental reasons. The front bund was a temporary element to allow and protect the construction of the quay wall. In stage 1 of the project, a temporary bund protection with limited design life was installed on the front bund as well as on the cross bund. Permanent bund protection was provided on the Stage 2 front bund and western cross bund.
The slope protection consisted of an armour rock layer and a filter rock layer on top of a geotextile. Since significant erosion of the seabed was feared, scour protection was installed consisting of fibrous open asphalt mattresses (FOSA).