Enough has been written about a Conservative government that knows its electoral success depends on Britain remaining a property-owning democracy, yet offers nothing beyond token gestures to stop the young being priced out of home ownership. Enough, too, has been said about graduates being overcharged, pensioners soaking up the largesse of the tax and benefit systems, the failure to upgrade infrastructure, the obesity crisis, and all the other problems that can’t be tackled because of half-thought-through Tory prejudices.

Allow me instead to concentrate on the scandal of the privatised water industry. Journalists and academics have been banging on for what feels like an age about an ‘organised rip-off’, to use the words of the usually sedate Financial Times. Few took notice, and that should not surprise you. Causes can appear marginal for years. Politicians see no need to address them. Then, with no warning to those who haven’t been paying attention, they explode.

Last week Michael Robinson of the BBC presented a superb documentary on what Thames Water had done to London and the southeast. Most infamously, the company poured 1.4 litres of sewage into the Thames near Marlow alone, destroying fish and fouling the home lives of river-side residents. The residents were also its customers. Not that Thames Water seemed to care. Water is a private monopoly. Why should it bother itself about the feelings of people who had nowhere else to go? After hearing how managers ignored warnings from workers about persistent equipment failures, Judge Francis Sheridan encapsulated their attitude when he said that the company had presided over ‘a shocking and disgraceful state of affairs’.

As shocking is the way that the former owners of Thames, the Australian bank Macquarie, was able to pass its costs on to the public. Macquarie took on £2.8 billion of debt to buy the company; it then loaded £2 billion of Cayman Islands debt on to Thames Water and its customers, despite giving assurances to the water regulator Ofwat that it would do no such thing. Macquarie has taken its profits. According to Martin Blaiklock, an infrastructure consultant, its investors received returns of 15 to 19 per cent over 11 years — twice the expected level. All it has left behind is a £2 billion debt and a very bad smell.

Now Thames Water is owned by a Kuwaiti investment fund and a Canadian pension fund. Its managers talk the soothing language of customer service and corporate responsibility. But when pressed by the BBC to say that they would not seek to imitate Macquarie and extract rapacious returns from a captive market, they refused to answer the question.

What interest do Kuwaiti and Canadian investment funds, Australian banks and Cayman Islands financiers have in ensuring the quality and affordability of our water? The hopeless regulators have no answers. Since Margaret Thatcher privatised English water companies in 1989, six out of the nine have pulled themselves off the stock market, meaning they do not have to release to their shareholders information that the regulators can scrutinise.

They promised to bring efficiency. Instead they have brought unsustainable levels of debt that, one way or another, the public will have to redeem. Researchers at Greenwich University say that in the past decade, the nine companies have made £18.8 billion of post-tax profits. Far from using the money to make the water system better, they have paid out £18.1 billion in dividends, and financed investment through loading £42 billion of debt on to consumers.

The university estimates the English are paying £2.3 billion more a year in water and sewerage bills than if the utility companies had remained in state ownership. These costs might have been bearable in good times, but as the Brexit-induced fall in the pound pushes real wages back down again, the prices of water, gas and electricity are bound to be political issues. Customers may not be overly keen to subsidise shareholders and lavishly overpaid managers.

I am not surprised that the Conservatives haven’t joined Labour in demanding the renationalisation of the water industry. It would cost about £70 billion, and in any case, Tories don’t nationalise. But why, after the Macquarie shambles, aren’t ministers and the regulators saying that secretive private equity and Middle East funds should not be allowed to control utilities? Why have they allowed Macquarie to move to the National Grid’s gas division? Ofwat is huffing that it has got tough, but it imposes no penalties on managers who break their commitments. After loading Thames Water with debt and flooding the Thames Valley with excrement, its then boss, the unimprovably named Martin Baggs, bagged a 60 per cent pay rise in 2015.

Conservatives claim to believe in the free market. If they did, they would view monopolies as Adam Smith viewed them — as conspiracies against the public interest. They would not care whether the monopolies were public or private. Both give consumers no choice. Both can put their customers’ interests last. But to the Tory mind, a distinction without a difference makes all the difference.

Because water companies are private monopolies, politicians and regulators back away from confronting them with the necessary anger and vigour. If a nationalised industry behaved as Thames Water has, they would be outraged. As it is, the mere fact that the monopolies are private is enough to persuade politicians to stand aside and let a scandal grow. No one will be more surprised than them when it explodes.