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The dam was built in 1953. Engineer J. van Overeem developed among other elements the pontoon sections with which the caissons were assembled. For the Waal River dam, 26 sections were used, resulting in a caisson of 230 meters in length (the width of the River), 9 meters high and 30 meters wide. For both the Rhine and IJssel Rivers, 10 sections were needed. The necessary testing was conducted at the Waterloopkundig Laboratorium (hydrology lab) in Delft, using a scale model of 1:10, with a single actual pontoon section in the lock next to the dam at Lith aan de Maas. In the event of the threat of war, the caissons would be sunk on top of a previously prepared asphalt sill in the river bottom. The caissons fitted exactly between two abutment piers, which were connected by multiple buttress dams to the high ground (winter dike). Both the buttress dams and the caissons were equipped with moveable gates which had to be systematically closed after the caissons were sunk. The project was substantially completed within the year, and identified as Plan D (Plan Deventer): the dam at Olst. In 1953 the entire IJssel Line was fully operational.