Three concrete pools at the Olympic aquatics centre are being tested with over 10 million litres of water this week, before being sealed and lined with 180,000 tiles.
The London 2012 aquatics dive pool and two 50m swimming pools are being tested for the 2012 games, which will also be open to the public after the games.
Testing of the dive pool and training pool is complete and the competition pool starts being filled this week.
Work is also underway lining the unique 160m long wave-shaped steel roof, which weighs over 3000 tonnes and rests on just three concrete supports.
The aquatics centre is on track to be complete in summer 2011 ready for test events and after the Games will provide two 50m swimming pools with moveable floors and separation booms, a diving pool and dry diving area for the full range of community and elite use.
ODA Chief Executive David Higgins said: “The aquatics centre is on track for completion in mid-2011 and the sweeping roof that will form the ‘Gateway to the Games’ is now a fixture in the skyline alongside the Olympic Stadium. Testing the pools is major milestone for the construction of the Aquatics Centre which in legacy will provide a range of swimming and diving facilities and become a new London landmark.”