Is it not a good time to re-nationalise the water companies (Watchdog accuses water groups of retaining £800m excess, 14th October)? It is hard to regulate natural monopolies, like public utilities, water in particular. With reduced corporation tax and lower borrowing costs water companies have benefited greatly resulting in the £800m windfall as reported by the NAO. Some of these companies are also publicly listed, such as United Utilities, Severn Trent and Pennon Group, paying generous dividends. Water companies should follow gas suppliers (albeit belatedly) and start passing on savings to consumers, or the government should threaten to nationalise partly, some of the companies, as Ofwat, the regulator seems to have not been able to do its job properly.