Thames Water began developing a desalination capacity at the Beckton site as early as 2003. The government's planning inspector recommended approval of the East London plant in 2007. Thames Water was given the go-ahead to develop the plant on the north bank of the Thames at Beckton that will desalinate up to 140Ml of brackish water a day.
The pilot plant takes water from the Thames, removes grit and grease and discharges it into a buffer tank.
From here it passes through a series of filters before reaching reverse osmosis membranes.
Here, saline water will be pushed over the membranes to remove the salt, allowing pure water to filter through.
Desalination is an energy intensive process and engineers at Beckton hope to use waste salt water to drive electricity turbines. This could help replace some of the energy lost in the desalination process.
The plant will be 100% powered by renewable energy, said Thames Water. The main energy source would be bio-diesel but the utility said it was also investigating whether some of the fuel could come from reprocessing used cooking fat and oil from homes, restaurants and takeaways.
In May 2008, the Mayor of London, Boris Johnson, dropped objections to the proposed plant at Beckton.
In 2004, previous Mayor Ken Livingstone directed Newham to refuse permission for the plant.
Thames Water appealed against the decision, and a Public Inquiry was held in 2006. The planning inspector dismissed the Mayor's arguments and recommended the project should go ahead. Livingstone launched a legal challenge to the decision, which was due to reach the High Court in May 2008.
Pipelaying works were due to begin in the Bushwood E11 area from Monday 4 August 2008. Thames Water expected them to be finished by the end of September 2008.