Thames Water’s owners only have themselves to blame for the writedowns | Nils Pratley

“We continue to view Thames Water as a long-term investment,” said the Universities Superannuation Scheme (USS), the £75bn pension fund for UK academics, as it wrote down the value of its stake in the Thames’ parent by nearly two-thirds, or almost £600m. Top marks for cheerfulness, but it’s a line that recalls the old joke about the definition of a long-term investment: a short-term investment gone wrong.

USS and Canadian pension fund Omers, the other late arrival on Thames’ register in 2017 (they replaced the departing Macquarie and its co-travellers), surely cannot have…