Tuesday, August 6, 2019
The Water Crisis In South Africa
The Water Crisis In South Africa South Africa is currently facing a water crisis. Our sources are scarce and they are constantly being polluted and exploited by unsustainable practices in areas such as agriculture and industry. Unless realistic goals and solutions are used to manage the water supply, we will become increasingly reliant on obtaining water from external sources. Sources of Water South Africas water resources have always been very limited, and with increased population, the demand for water has also increased. This puts a lot of strain on South Africas water supplies because 65% of the country gets less than 500mm of annual rainfall. This rainfall is inconstant and is often contaminated by silt and erosion. There are various areas where South Africa stores and extracts water. Most of the water we use comes from surface run-off (9 500 million m3/year of the total of 12Ã 871 million m3/year), about 78.5%. Most run-off from rainfall is held in dams such as the Gariep dam, the Vaal dam and the Sterkfontein dam. 66% of water in main rivers is not used for economic or social purposes but remains in the rivers. Another source of water is groundwater held in aquifers. This water is transported by underground pipe systems. It can also be brought to the surface by digging wells or building boreholes. Groundwater supplies about 10% of our national water supply. Becaus e South Africa does not have the resources to supply the countrys water demand, we import extra from Lesotho. This may result in dependency on countries such as Lesotho. Long term plans such as desalinisation of seawater could be used to supply water, but solutions such as this one are very expensive and difficult to do. Availability and Distribution Distribution of water in South Africa is very uneven as there is a shortage of water in the west but an abundance in the east. This is due to the warm Mozambican current that flows along the eastern shore in South Africa, contributing to humidity and heavy rains. The cold Benguela current runs along the west coast reduces the amount of water held in the air. The South Indian High Pressure is also located along the east coast. The high pressure brings high amounts of rainfall to the eastern side of South Africa. The South Atlantic High Pressure also brings rain to the western side of the country but only in winter when mid-latitude cyclones are present. These factors cause a huge difference in the amount of rainfall experienced on either side of the country, resulting in rainfall higher than 500mm in the east, and lower than 500mm in the west. Because of this huge inequality, water in South Africa is very scarce and not readily available, causing us to import water from other countrie s such as the aforementioned Lesotho. Water supply in cities is also lower than in rural areas. For example, in Cape Town, because rainfall is scarce in the summer and spring seasons, water for domestic and industrial use is pumped into the city by underground pipe systems. A lot of the water in South Africa cannot be utilized as it is either salty seawater or it has been polluted by people, industry and agricultural practices, negatively effecting availability in the country. Usage by Economic Sectors Water is utilized by three main economic sectors; agriculture, factories and forestry. In agriculture, which uses 64% of South Africas available water, water is used for irrigation and livestock. Using it for crop farming can be damaging because the water is polluted by chemicals such as insecticides and pesticides. This infiltrates into rivers and groundwater and can reduce South Africas available water resources. 29% is used in factories and manufacturing. This can also be harmful as the water is mixed with poisonous chemicals such as nitrates before being released back into the environment. The other 6% of water used in the economic sector is used in forestry. It is used to irrigate forestry plants for companies such as SAPPI who produce paper and the like, until the forest is well enough established to grow and thrive without irrigation. The water that is used in the economic sector reduces the amount of water that can be used domestically. The water used in these sectors is also often utilized in unsustainable manners, as it returns to the environment containing pollutants. Another economic sector which utilizes water unsustainably is the mining sector. Mine shafts often become flooded and excess water from the mines is released back into the environment containing highly toxic pollutants and sediment from the mines. Management and Solutions There are multiple ways in which water can be used sustainably. Agricultural sectors can reduce the amount of fresh water they use by using grey water from areas such as drain pipes to water crops and gardens. Grey water can also be used in toilet systems. The forestry sector can use sustainable practices such as planting indigenous trees which use less water than alien species such as gum trees. To conserve water in the household, public messages could be sent out by the government and municipalities to shower instead of bath, and to avoid planting alien species in their gardens, such as roses and pansies. The government could fund new projects such as the construction of new dams which would be used domestically, in industry, for irrigation and for hydroelectric power. However, this does have a negative aspect to it, as dams are very expensive to build and can often be damaging to the surrounding environment if not designed properly. Another step which could be taken to conserve So uth Africas water is wetland conservation. Wetlands can regulate pollutants and diseases carried in water. Wetlands reduce erosion, they purify water and they contain bacteria which break down organic compounds. They also prevent droughts and floods which saves the government about R21 million. Wetlands also help regulate river flow which is where we get most of our usable water from. Another form of managing water is Water harvesting. This involves collecting rain water during a storm and preventing it from running off. Not only does this prevent erosion, but this water can then be used for agricultural purposes instead of fresh river water. This is a cheap, easy practice which can be implemented on all farms. A simple way to prevent water wastage is by controlling unnecessary losses. These can come in the form of pipe leaks and wasteful irrigation methods. Water pipes should be strictly monitored and regularly checked to ensure that no water is being lost through leakages. Irrigat ion methods such as canals and spraying are unreliable, because while the water is in the canals it can infiltrate into the soil or evaporate before it reaches the crops so extra water has to be used. Spray irrigation is unreliable as the wind can blow the spray away before it reaches the crops. Methods of irrigation such as drip irrigation should be implemented as it is much more efficient Conclusion Although water resources in South Africa are currently being over-exploited and unsustainably managed, there are multiple methods of conservation which can be implemented to improve South Africas permanent water supply.
Posted by r at 1:44 AM