Water, Sewage & Effluent November December 2018 | Page 37

Water Sewage & Effluent November/December 2018 innovations historically dependent on one single water source type, namely surface dams fed by run-off. Even if this means a series of dams like Cape Town or a complex system of water transfers like Gauteng, such cities still depend on one type of supply and that is rainfall. Therefore, our water provision remains extremely vulnerable. So, when droughts ‘sneak up’, there will be problems, and as the hunger stones predict, a fair amount of hardship and weeping. The lesson from other parts of the world, and now also from Cape Town, is that any city or area must plan and manage a portfolio of water sources. That means investing in a more diversified water supply such as underground sources, desalination, and water re-use. Water planners need to look 35 www.waterafrica.co.za an inscription dating back to 1616, which reads: “Wenn du mich sieht, dann weine” (if you see me, then weep). A fellow hunger stone in Germany commemorates numerous droughts going even further back in history, and the message is no less dire: “If you again see this stone, so you will cry; so shallow was the water in the year 1417.” Fortunately, the human race has been able to reduce hunger through scientific and engineering developments over the past centuries. But, despite water being stored in dams and having sophisticated water supply systems, we are still vulnerable to droughts as the past few years have acutely proven. South African towns and metropolitan areas such as Cape Town and Nelson Mandela Bay (Port Elizabeth) are I n an interesting opinion piece by Terry Mackenzie-Hoy in Engineering News, debating climate change (and without participating in that dispute here), I refer only to his mentioning of the inscribed boulders in the Czech Republic, known as Hunger Stones. Hunger Stones’ historical messages would normally remain hidden below the water line of the Elbe River. However, as the water level dropped due to a severe Central European drought, the sinister rocks and the words inscribed on them have been exposed once again. These boulders typically have a date that recorded when the water of the river was at that particular level, and sometimes an inscription was added. The oldest and most famous of these landmarks, simply known as Hunger Rock, contains