In the absence of the Beckton plant, Thames Water will have to rely more on households to reduce their consumption. He has already asked bill payers to let their lawns turn brown and their cars stay dirty ahead of a planned ban on hosepipes in the capital.
“Payers will rightly question the value for money they have seen from the significant investment in this plant,” said Karen Gibbs of the Consumers Water Council.
Industry experts say Thames Water opted to place the facility in an estuary, where it hoped to reduce operating costs because seawater, mixed with fresh water from the Thames, would be less salty and therefore less difficult to process.
But the company failed to take into account that the water would be at different salinity levels at different times of the day, making the plant unreliable for producing a constant supply of potable water.
Even when the plant is operational, it will produce less potable water than Thames had originally planned. The plant was originally intended to produce around 150 million liters of water a day, enough for 900,000 Londoners, but was forced to revise the estimate down by a third earlier this year.
“This adjustment was made on the basis of experience and to avoid creating unrealistic expectations about the output that could be achieved over a sustained period,” a Thames Water spokesman said.
The impetus for the east London plant had been the 2012 London Olympics, which led to concerns that an influx of people during the hot summer months could be disastrous for the water supply of the city.
But the initial plans proposed in 2004 were blocked by Ken Livingstone, then the Labor mayor of London, who argued the plant was unsustainable and unnecessary, despite the city being in one of the most water-stressed parts of the country.
When Boris Johnson became mayor in 2008, the plant was given the green light, and construction was completed two years later.
Thames Water had originally planned four more, but there is little sign of plans for a new plant.
It’s an experience recently replicated in Hampshire, where Southern Water was forced to abandon plans for a desalination plant last year. The area will be the first in the UK to be under a hose ban, which starts on Friday.
The plant had been opposed by green groups, environmentalist Chris Packham and Julian Lewis, the local Labor MP.