Thames Water has been left racing to secure cash once again after its investors withdrew a £500 million funding lifeline that was due at the end of this month. Britain’s biggest water supplier is blaming regulator Ofwat for making its plan “uninvestible”, but has faced accusations of trying to “blackmail” the regulator into accepting its demands to hike customer bills by 40%. Here we look at what is behind the latest funding crisis at the utility giant and what it means.