Londoners will next year be drinking water from a desalination plant – a type of facility more commonly associated with the arid Gulf region – if the current dry spell continues, Thames Water has warned.

The company, which supplies water and sewerage services to 8.8m customers in the capital and along the Thames Valley, said it would activate its emergency plant based in Beckton to the east of the capital from the turn of the year if the current conditions persist.