Cape Town, South Africa, may become the first modern city in the world to run out of water. This headline is being strewn across news networks around the world. Time is ticking toward ‘Zero Day’ - a day in April when the Cape is set to run out of water.
Cape Town residents are now restricted to 50 liters of water per household per day and this figure is soon to be halved.
Professor Mike Muller, the former Director-General of the Department of Water Affairs and Forestry (1997-2005) released a report in June 2017 named: Understanding the origins of Cape Town’s water crisis. He wrote:
“The water crisis that has confronted Cape Town this summer should be of concern to all professional engineers in the field of water management. How was such a critical situation allowed to develop in one of South Africa’s largest cities?”
The history
Ever since the colonization of the Cape by Dutch settlers in 1652 crippling droughts have been experienced. Between 1699 and 1732 it became clear that the Cape was moderately arid. Some excerpts from the Precis of the Archives of the Cape of Good Hope read:
October 29, 1699: The grain-crop suffering from drought. Rain wished for. Bad harvest feared.
January 29, 1700: The Governor refers to the poor harvest, caused by floods and succeeding droughts; the consequent want of grain here, and the necessity of making provision for supplies.
May 7, 1700: All the farmers are complaining of drought, as the ground is too hard to plough without rain, and the cattle for want of pasture is very poor and dying. Prayer should be made to Almighty God to preserve us from a third bad harvest, as our condition would otherwise be very miserable.
January 13, 1702: The south-easter blowing still (from before New Year, with slight pauses), causing the destructive drought to continue.
The word ‘drought’ is written 15 more times in the first volume of the Precis of the Archives of the Cape of Good Hope. In 1711 there was a drought. In 1713 after five months of no rain it finally came in March. In 1714 drought struck again. In 1725 there is another reference to a severe drought which again would produce a bad harvest.
Farmers had the same problems back then that they have today: devastating droughts followed by incredibly destructive storms and crops that either fail or are poor.
The situation has, however, changed over time - a change which further burdens already stretched resources. The population in the Western Cape has grown exponentially in recent years, exacerbated by migration to this southernmost tip on the African continent. And the city of Cape Town has borne the brunt. There is an estimated metropolitan population of between 3.5 and 4 million people with a population density (back in 2016) of 1,530 people per square kilometer. The population in Cape Town in 1955 was a mere 705,000.
A solution which factors in burgeoning growth is needed urgently. The water shortages today are dire; little seasonal rain in their 2017 winter have seen dam levels fall to desperately low levels – they are currently sitting below 30% and already potentially tainted.
The Eastern Cape’s dams are also in trouble as the drought bites there too. Experts believe that if the Cape experiences three years of seasonal rains they may be back on track.
In the interim what can engineers do to solve the crisis?
Prof Mike Muller goes on to write that if the Cape had wanted to avoid these latest water restrictions the government should have imposed technological ‘interventions’ in a timely manner.
There is a flurry of activity now, but the overarching question is: Can engineering save the Cape from its water crisis in time – enough to satisfy the daily city consumption of 580-million liters?
The Mayor of Cape Town, Patricia De Lille, has acted to contribute to the solution; she has called upon major drilling companies in the country to drill in “prime locations” to access aquifers she says could produce 150-million liters per day.
The drilling engineers will access these ancient water reserves that have been untouched for millions of years, says Mayor De Lille. Engineers and scientists will then ensure the water is potable before introducing it into the water supply. Work has started in the Cape Flats Aquifer.
This is likely to be a short term solution – once the water has been harvested the aquifers may struggle to replenish themselves - especially if the drought continues.
With the conservation of water being key, intelligent water pressure management technology has been implemented in the Cape. It will prove to be an efficient way of preventing damage to existing infrastructure and ensure that people do not use more than is necessary in these tough times. The City of Cape Town put out a statement saying:
“Not only does pressure management generally lower consumption by reducing the rate at which water flows to properties, it also reduces leaks and pipe bursts by better ensuring that pressure remains within levels that the pipework can tolerate, and reduces the rate of loss from leaks and bursts. At all times, careful consideration will be given to ensure minimal disruption to the water supply in affected areas.”
University of Cape Town Future Water Institute’s Dr Kevin Winter spoke to Talk Radio 702 about the aquifers. He believes that if the locals could reduce their water consumption to below 450-million-liters per day, it would be a significant saving. He also suggests that treated effluent get injected into the aquifers to assist with their recharging.
If and when the storms come the storm-water must be trapped and fed into the aquifers too.
Finally and long-overdue, three new desalination plants will be implemented in the Cape. For residents who have been subjected to water restrictions for quite some time now, it may be too little too late, but at least they offer a sustainable solution.
Works Cited
“Drilling on Cape Flats Aquifer Starts as Cape Town Dams Dry up in Drought.” News24, 11 Jan. 2018, www.news24.com/SouthAfrica/News/drilling-on-cape-flats-aquifer-starts-as-cape-town-dams-dry-up-in-drought-20180111.
“EDITORIAL: Parched Cape Runs out of Time.” BusinessLIVE, www.businesslive.co.za/bd/opinion/editorials/2017-10-30-editorial-parched-cape-runs-out-of-time/.
Muller, Mike. “Understanding Cape Town's Water Crisis.” By Mike Muller :: SSRN, 5 July 2017, papers.ssrn.com/sol3/papers.cfm?abstract_id=2995937.
“Precis of the Archives of the Cape of Good Hope : Cape of Good Hope (South Africa). Archives : Free Download & Streaming.” Internet Archive, 1 Jan. 1896, archive.org/details/precisofarchives01capeiala.
http://worldpopulationreview.com/world-cities/cape-town-population/
