Construction of the bridge started immediately after the creation of the PFI in 1988. It was designed by German civil engineer , with the UK's Halcrow Group acting as category 3 check engineer, employer's agent and engineering adviser. The two main caissons supporting the bridge piers were constructed in the Netherlands. Each caisson was designed to withstand a bridge strike of a ship weighing up to 65,000 tonnes and travelling up to The bridge deck is about high, and it took a team of around 56 to assemble its structure. During construction of the approach road, a World War II bomb was found in its path, which required closure of the entire crossing.