Water Week 2022
With rain falling again in many parts of South Africa, people are likely to think that any crisis is over.
If dam levels are increasing, why should everybody keep on saving water?
Why do we have to save water?
The fact is that in South Africa, and in many other parts of the world, water simply is not available in abundance anymore. If we look at the water that we have, and the changes that are taking place around it, it becomes clear that we cannot waste any water, any longer.
How much water is there?
Water covers 70% of the earth’s surface, but almost all of it (96.5%) is salty. Found in the oceans, this is not water that we can drink (unless it’s treated with expensive desalination processes). Only about 3.5% of the earth’s water is fresh; most of this is trapped in glaciers (about 68%); and, around a third is underground. The last 2% is in rivers, lakes and streams. There’s also some water in the atmosphere (clouds). According to NASA, if you put all the freshwater together, it would form a ball of about 1 400 kms wide.
This amount of water has remained fairly constant, recycled endlessly up and down the atmosphere, through plants, rivers, animals and people (the water cycle). According to some studies, the water you drink is over 3.8 billion years old, at least.
Most of this water is found in a few places, like the Amazon basin, Canada and Alaska. Paradoxically, these are places where there are relatively few of the earth’s nearly 8 billion people. South Africa itself is seen as a water-scarce country. Our average annual rainfall is only 495 mm, about half of the world average. The United Nations Economic Commission for Africa notes that since 1990 South Africa has shifted from being “water stressed” to be a country of water scarcity. According to the commission, South Africa will experience the 9th lowest levels of water availability per person in Africa by 2025.
So, though there is a lot of water on the planet, it is distributed unevenly, and mostly in places where there are not many people. Additionally, South Africa is not privy to a large share of this water.
Some water sources for our future
According to the National Water and Sanitation Master Plan, re-use of effluent is becoming more cost effective as technologies have improved. Effluent is the liquid that is discharged after a processing step, usually from an industry, water purification works or a waste water treatment plant. Already, treated effluent from wastewater and acid mine drainage (AMD) is being used to supplement water supply and this can be expanded considerably. As the cost of desalination decreases with advances in technology, desalinated water (from the sea, brackish groundwater and waste water) makes increasing economic sense. While the use of desalinated sea water is only financially feasible for coastal areas, it will free up surface and groundwater for upstream and/or inland use where water is currently transferred to coastal areas. Water quality and quantity can be further improved through planning for, restoring and maintaining ecological infrastructure such as strategic water source areas and wetlands. These are currently under-protected and often in poor condition. Investing in ecological infrastructure is often a cost-effective method for enhancing and supporting investment in built infrastructure.
Did you know : South Africa is the 39th ‘driest’ country in the world
Every day, more and more people
The total number of people currently living on the planet was estimated at 7.7 billion in April 2019. It took over 200 000 years of human existence to reach 1 billion, but in only the last 200 we became a group of 7 billion strong. Yet, the amount of water that everybody needs to share, stayed the same.
Yet more people, will have to compete
for even less water
These people are not spread evenly across the planet. Most live in urban areas (towns, cities and suburbs) – already more than half (55%) and by 2050, 68% of us will choose to make our homes there.
Translated into numbers, the amount of people on the move towards cities are staggering. According to the United Nations’ (UN’s) World Urbanization Prospects Report for 2018, the rapid increase in the urban population entails a growth of 751 million people in 1950, to 4.2 billion in 2018. Projections add 2.5 billion people more to the planet’s urban population by 2050. Almost 90% of this growth is taking place in Asia and Africa.
In South Africa, the highest growth is taking place in Gauteng, which grew with 3 392 495 people between 2008 and 2018. To put it in perspective, Gauteng is now adding an extra Soweto every five years (the population of Soweto in 2016 was 1 480 000).
In the process, everybody needs a home, water and sanitation. It shows. According to the United Nations, water use has grown at more than twice the rate of opulation increase in the last century.
In South Africa, according to forecasts by the Institute for Security Studies, we will demand 17% more water than is available by 2030. This gap between supply
and demand is unlikely to close, even if we are able to implement all plans to find more water, like opening desalination plants, pumping more groundwater and using less water.
In many places, water pollution is rampant, and South Africa is no exception. According to the National Water and Sanitation Master plan, between 1999 and 2011 the extent of main rivers in South Africa classified as having a poor ecological condition increased by 500%. Some of these rivers have been pushed beyond the point of recovery.
This has direct consequences for the water we all rely on. Further fuel to the flame is added by droughts, which will always be part of the South African climate.
How much water do we have?
The combined storage capacity of large dams is in the order of 31 000 million m³. We can also potentially access about 4 500 million m³ of groundwater per year, though we are only making use of 2 000 and 3 000 million m³ at the moment. There are also about 5 000 registered dams throughout the country, most of which are small (less than 12m) and are used by farms and municipalities. At the moment (by March 2020), the country’s reservoirs were at 60% capacity, storing a volume of 21 189.3 m³.
Because of how we get our water (through rain) and distribute it (via dams and transfer schemes), the answer to how much water we have in South Africa always comes in rainfall amounts, and dam levels.
South Africa has less water per person than Botswana & Namibia
As mentioned, our rainfall varies widely, but the average total runoff (water that flows over the land after rainfall, instead of being absorbed into groundwater or evaporating, for example) that the country receives per year is about 49 000 million m³/a. We can’t capture and store all of this. Our surface water can reliably provide us with about 10 200 million m³ each year.
The Department of Water and Sanitation announced that sporadic rainfall during the summer had supplied enough water for basic use in Gauteng, KwaZulu-Natal, Mpumalanga, North West, Free State and parts of Northern Cape. However, it did not rain enough to break the drought in Eastern Cape and parts of Northern Cape.
Gauteng recorded the highest dam levels at 98.1% and the highest volumes of water stored in its reservoirs. This was followed by Northern Cape at 90.2% and Mpumalanga at 75.2%. The Western Cape stood at 44.1%, but this was expected to be boosted by heavy winter rains that would hopefully start in late May. Limpopo, again, has seen regular rainfalls that have increased the province’s dam level from 46% in the past four months to 68.4%. Yet, we will not be able to meet our ever-increasing demand for water, if we keep on relying on the rain, and the surface water that results from it.
Where does our water come from though?
If you think it’s from your tap, think again. Instead, the simple act of turning the faucet to get running water is only the small end result of an intricate water delivery system, far removed from the rain that falls outside your window.
About 45% of the water in South Africa comes from rivers shared with neighbouring countries.
Where your water comes from, and how it gets to you, depends on the place where you live and the systems that the people that manage it put in place. In many parts of Central Asia, for example, water is captured in permanent glaciers, and in the summer season, the melting ice fills the main rivers. In Saudi Arabia, about 50% of drinking water is from the sea (desalination). We depend mainly on surface water, says media liaison for the Department of Water and Sanitation, Sputnik Ratau. In South Africa, we are heavily dependent on rainfall to replenish these rivers and dams, as well as groundwater. This has had vast consequences to our country, the places we call home, and our ability to make a living there.
Water supply in South Africa
South Africa has an arid to semi-arid climate, with an average rainfall of 465 mm each year (about half the world average). This number paints only a small part of the picture of water availability in the country.
When, and where that rain falls varies greatly. All but the south-western and southern regions of South Africa rely on summer rainfall. The rainfall is also heaviest in the east, and decreases as you go west. In fact, about 50% of South Africa’s water resources originate from only 10% of our land. These ‘high water yield’ areas are like water factories, and contribute significantly to the overall water supply of the country, supporting the growth and development of places far away.
According to the Department of Water and Sanitation’s National Water and Sanitation Master Plan, South Africa’s dependence on surface water will proportionately decrease over the coming decades. The plan states that by 2040, treated acid mine drainage and desalinated seawater will make a significant contribution to South Africa’s water mix. In the future, we will make more use of groundwater, in an effort to reduce our reliance on the water above ground.
Not only is the rain distributed unevenly over the landscape and through the year, but it can also fluctuate over the long term. Droughts don’t often occur over the whole country at once but there are years when the entire summer rainfall region is affected.
Because of this, we are a country that stores, and moves water to where and when it is necessary. Our large dams can store up to two thirds of the country’s total annual runoff, and most of our large rivers are now heavily used and regulated in order secure a water supply.
By moving water from catchments where there is a lot of water, to those where there are not enough, we can mine, farm and build cities, where it would otherwise not have been possible. In this way, many of our major cities and industrial developments are actually located far away from the water necessary for it to function. Gauteng, and the Nelson Mandela Bay Municipality and surrounds, are two good examples.
Our water is too dirty
Water pollution in South Africa is rampant. Agriculture, runoff from irrigation, industrial effluent and discharges from mining and human settlements all contribute to our water quality problems.
According to the DWS South Africa’s water crisis is also caused by insufficient water infrastructure maintenance and investment, unequal access to water and sanitation, deteriorating water quality, and a lack of skilled water engineers.
According to statistics from the DWS, about 56% of the more than 1 150 municipal wastewater treatment works and 44% of the 962 water treatment works in the country are in a poor or critical condition and in need of urgent rehabilitation and skilled operators. Some 11% of this infrastructure is completely dysfunctional.
The results are showing in our renowned natural environments. Between 1999 and 2011 the extent of main rivers in South Africa classified to be in a poor ecological condition increased by 500%. Some rivers have been pushed beyond the point of recovery.
Fifty percent of South Africa’s wetlands have been lost, and of the remaining 3.2 million hectares, one third are already in a poor condition.
Winter says we do not have to look farther than our coastlines for more proof. Here, the high number of threatened amphibians is a reflection of the price of high density developments and the impact of pollution flowing via our rivers inland towards our seas.
