Queen Elizabeth Olympic Park sits on what is termed a 'brownfield site', meaning that the land was previously used for industrial buildings. It also means that there might be contamination of the land and water left over from the factories.
This was certainly true on this land, which had been used for factories making paint, chemicals, dyes and other smelly and possibly poisonous products. To make the Olympic site, the organisers arranged for a massive cleanup operation to clear out the waterways. Over 3,500 holes were drilled into the earth to test each area for pollution.
There was also the 'soil hospital' - two giant machines that could test, analyse and treat the soil on site to remove contamination. The hospital successfully treated over 1.7 million cubic metres of earth, which now forms the surface layer of the park.
Landscaping teams used this soil and the crushed remains of the old industrial buildings to change the shape of the land, making some areas higher to prevent flooding. But they also used natural methods of dealing with floodwater, leaving two low-lying areas in the north park to act as natural 'wetlands bowls' to fill with water when the rivers start to rise.
Next: Planning a Park
