Obviously, in a project of this size, the designers and engineers had to overcome several major problems.
The site was south facing, sheltered and with a huge crater big enough for 35 football pitches where china clay had been quarried. However, the crater was prone to flooding. Engineers tackled this by devising a drainage system that filters all the water coming onto the site through matting. This is collected in a vast sump (pool) under the site and reused in the biomes.
As the site was an old quarry, there was no soil in which to grow the plants! This was overcome by creating an 85,000 tonne compost
heap, in which composted green waste was combined with china clay waste.