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• Thames Water supply ‘on knife-edge’

When Sarah Bentley and Sarah Albon met at Beckton sewage treatment works in east London, the choice of location was designed to underline Thames Water’s predicament.

The site is Europe’s largest sewage treatment operation, with Grade II-listed parts of the site dating to the 1860s. It is now connected with the new Thames Tideway super-sewer, but insiders say several parts of the site are simply crumbling. The site is also riddled with asbestos.