It's a pity that Helen Zille chose desalination as an example of an area where governments are innovation-shy.

There is a small company in the Western Cape that, some years ago, had some useful patents on desalination. They are now largely outdated because, yes, technology advances.

But technological advances have not yet reduced the cost of desalination to the point that it is competitive with the alternatives available to Cape Town - such as groundwater from the Table Mountain aquifer or a top-up of Voelvlei from the Berg River.

Indeed, a careful analysis of the decision-making record to be published later this month will show that the immediate cause of the Cape Town crisis was the decision of politicians and senior officials to override expert advice because they knew best. I could call it colonial ignorance but it is actually part of a global trend to argue against physical reality, epitomised by that man in the USA. So perhaps it is just normal Capetonian arrogance?