The Doel plant was originally designed for a 10,000 year flood of 9.13 m TAW (Tweede Algemene Waterpassing). The highest measured level was 8.10 m TAW during the North Sea flood of 1953. The site was filled to 8.86 m TAW during construction and fitted with a seadyke of 12.08 m TAW. The other dykes around the site have a height of 11 m TAW. Probabilistic studies performed after Fukushima showed the height of a 10,000 year flood had slightly increased to 9.35 m TAW, 22 cm higher than the studies performed in the 1960s. The highest possible tsunami is lower than 0.5 m. During post-Fukushima stress tests a dyke failure with a water level of 10.2 m was simulated. Due to the presence of bulkheads and pedestals in the buildings no safety functions were endangered.
