While Cape Town could be over the worst of its water crisis by 2019, residents and businesses in Johannesburg, Ekurhuleni and Tshwane must prepare for a dry and uncertain decade ahead. Good rains left the Highveld’s dams full at the end of summer. But those dams, which together comprise the Vaal system, will have to supply the rapidly growing population in Gauteng and surrounding provinces until 2025. That’s the earliest that the Polihali Dam, centrepiece of Phase 2 of the Lesotho Highlands Water Project, can be completed. It took just a minor drought in 2015-16 and a heatwave in 2016-17 to provoke panic as restrictions were introduced and water supplies were throttled in many urban areas. If we have a repeat of such a dry period over the next eight years, our growing population and their growing demands will make sure it feels much worse. But if we suffer a serious drought in the areas that feed the Vaal system, Cape Town’s crises will look like a picnic. An important management pr...