Concrete factory
Concrete factory
The construction of the storm surge barrier was so large-scaled and complicated that it could not be left to one single building contractor. No single building contractor could promise that the dam could be finished for a fixed price and within a certain period of time. Therefore, a so-called ‘framework contract’ was drawn up, consisting of a general framework which could be filled up in a later stadium. In 1977, the Ministry of Waterways and Public Works concluded a contract with the Oosterschelde Storm Surge Barrier Building Combination (in Dutch: ‘DOSbouw’). This combination was formed on September 1st, 1976 by eleven building contractors:
· Ballast-Nedam Groep Inc
· Bos Kalis Westminster Group Inc
· Baggermaatschappij Breejenhout PLC
· Hollandse Aanneming Maatschappij BV
· Hollandse Beton Maatschappij PLC
· Van Oord-Utrecht PLC
· Stevin Baggeren PLC
· Stevin Beton en Waterbouw PLC
· Adriaan Volker Baggermaatschappij PLC
· Adriaan Volker Beton en Waterbouw PLC
· Aannemerscombinatie Zinkwerken PLC

Some of the ships that were used during the construction, were owned by the combination (‘Jan Heymans’ and ‘Johan V’). Other ships were built under the authority of the Ministry of Waterways and Public Works (the condensation pontoon ‘Mytilus’, the mat installer ‘Cardium’, the lifting ship ‘Ostrea’ and the mooring pontoon ‘Macoma’). DOSbouw was located at the port in Burghsluis and was removed after the completion of the barrier on the 30th October 1986. The purchase of building materials remained outside the contract and was directly arranged with the suppliers from within and outside the country. A separate framework contract was concluded with the Combination of Construction Companies Oosterschelde (also called ‘Ostem’), for the construction of the closure materials, such as the slides.