and there are serious questions about its future, as it is billions of pounds in debt. 0ur environment correspondent, jonah fisher, has more. a stretch of river near gatwick airport once popular with local anglers. full of dead fish. this was the aftermath of the sewage spill in october 2017. investigators counted more than 1400. the realfigure is likely to have been much higher. the fish died when raw sewage was pumped out of this water treatment facility. it was a mistake but in court the environment agency listed a catalogue of errors thames water had made both before and after the spill. warning signs were ignored, infrastructure was inadequate and, infrastructure was inadequate and, in the days after the incident, britain s biggest water company deliberately misled investigators.