On Friday July 27, the 2012 Summer Olympics held its spectacular opening ceremony in London. The four billion viewers of these Games are also treated to arguably the most sustainable Olympics with distinctive venues and innovative use of concrete. More than 45,000 construction workers, construction companies, engineering and architectural companies were responsible for creating the amazing, green venues, including the Olympic Stadium which is one the most sustainable buildings ever, featuring:

• Capacity of 80,000 to be reduced to 25,000 from the lightweight innovative design;

• Concrete produced on site, using recycled content and with the raw materials being supplied to the site by rail contributing to a 42 percent reduction in carbon emissions compared to the average concrete used in the UK; and

• 230,000 cubic feet of crushed concrete, recycled from other parts of the Olympic Park, placed on top of the ground, creating a solid base for the stadium’s construction.

The Aquatics Centre, an iconic part of the ‘gateway' to the Olympic Park, features:

• A stunning wave-like roof, 525 feet (160 m) long and 262 feet (80 m) wide which weighs more than 2,880 tons resting on just two concrete supports at the northern end and the second one at a single wall at the southern end, which have been built with over 20,000 tons of concrete;

• 1,200 piles of reinforced concrete in the foundation – mostly tension rather than compression – to offset the probability of a 'buoyancy effect," (when pools are left empty);

• Ground granulated blast furnace slag, a byproduct of steel production, added to reduce the necessary cement content by 50%; and

• A 2,953 ton concrete bridge built to span and protect the tunnels which have been dug to run power lines beneath the site. 

While the’ "Bird’s Nest" and other Beijing Olympic venues are unused empty shells, many of the London venues will be deconstructed, dismantled and reused after the Olympics are finished. The London 2012 organizers hoped to build a sustainable legacy as well as a sporting one.