Editing Water supply and sanitation in South Africa (section)

==Water resources and water use==
[[File:Katse Dam,Lesotho,Africa.jpg|thumb|250px|The [[Katse dam]] in Lesotho is an important source of water supply for the arid Gauteng area around Johannesburg, the industrial heartland of South Africa.]]
Water availability in South Africa varies greatly in space and time. While the West is dry with rainfall only during the summer and as low as 100&nbsp;mm, the East and Southeast receive rainfall throughout the year with an average of up to 1,000&nbsp;mm. Total annual [[surface runoff]] is estimated at 43 to 48&nbsp;km<sup>3</sup>, depending on the source.<ref name="FAO Aquastat">FAO Auqastat: [https://www.fao.org/nr/water/aquastat/countries/south_africa/index.stm South Africa 2005]. Retrieved 24 October 2010</ref><ref name="Earthtrends">World Resources Institute: [http://earthtrends.wri.org/pdf_library/country_profiles/wat_cou_710.pdf Water Resources and Freshwater Ecosystems – South Africa]. Retrieved 24 October 2010</ref>

Much of the runoff is lost through flood spillage, so that the available surface water resources are estimated at 14&nbsp;km<sup>3</sup>/year only. Although groundwater is limited due to geologic conditions, it is extensively utilised in the rural and more arid areas. Available groundwater is estimated at 1&nbsp;km<sup>3</sup>/year. The main rivers of South Africa are fairly small compared to the large rivers of the world: For example, the discharge of the Nile River alone is about six times higher than the available surface water resources from all South African rivers together.<ref name="Orange-Senqu River Commission">[http://www.orasecom.org/ Orange-Senqu River Commission]. Retrieved 18 June 2011</ref><ref name="Limpopo Watercourse Commission">[http://www.limcom.org/ Limpopo Watercourse Commission]. Retrieved 18 June 2011</ref>

The main rivers are the [[Orange River]] draining to the Atlantic Ocean, the [[Limpopo River]], the [[Incomati River]], the [[Maputo River]], the [[Tugela River]], the [[Olifants River (Limpopo)]], and the [[Breede River]]. The uMkhomazi, Maputo, Thukela and Limpopo all drain to the Indian Ocean. South Africa's most important rivers are transboundary: The Orange River is shared with Botswana, Namibia and Lesotho, the "water tower" of Southern Africa. The Limpopo-Olifants river basin is shared with Botswana, Zimbabwe and Mozambique, which lies the furthest downstream. International commissions of all riparian countries have been set up to manage these transboundary water resources.<ref name="Orange-Senqu River Commission"/><ref name="Limpopo Watercourse Commission"/> Potential future water resources are seawater [[desalination]] or the transfer of water from the [[Zambezi River]].
 
Total annual water withdrawal was estimated at 12.5&nbsp;km<sup>3</sup> in 2000, of which about 17% was for municipal water use.<ref name="FAO Aquastat"/><ref name="Earthtrends"/> In the northern parts of the country, both surface water and groundwater resources are nearly fully developed and utilised. In the well-watered southeastern regions of the country significant undeveloped and used resources exist.<ref name="FAO Aquastat"/> The [[Gauteng]] area around Johannesburg, which is very water scarce, receives water from various dams in the area such as the [[Vaal Dam]] and imports water from the Orange River system through the [[Lesotho Highlands Water Project]], in particular from the [[Katse Dam]].<ref>Rand Water:[http://www.randwater.co.za/AboutUs/Pages/Background.aspx Background] {{Webarchive|url=https://web.archive.org/web/20190209124346/http://www.randwater.co.za/AboutUs/Pages/Background.aspx |date=9 February 2019 }}. Retrieved 24 October 2010</ref> Cape Town receives its drinking water from an extensive system of rivers and dams, including the [[Berg River Dam]].

Cape Town has 26 treatment plants, some of which are ineffective and date back to the 1950s, making clean water access and [[Wastewater treatment|wastewater management]] major difficulties.<ref name=":32">{{Cite book |last=Bank |first=European Investment |url=https://www.eib.org/en/publications/the-clean-oceans-initiative |title=The Clean Oceans Initiative |date=2022-02-04 |publisher=European Investment Bank |language=EN}}</ref> 

Cape Town will receive an €80 million loan from [[KfW]] to assist the city in improving and expanding different municipal [[wastewater treatment]] plants, a €1.2 million grant for training and a €4.5 million grant for city-supporting measures. The upgrades will allow the city to use recycled water for agricultural or industrial purposes and assist in dealing with droughts.<ref name=":322">{{Cite book |last=Bank |first=European Investment |url=https://www.eib.org/en/publications/the-clean-oceans-initiative |title=The Clean Oceans Initiative |date=2022-02-04 |publisher=European Investment Bank |language=EN}}</ref>

===Wastewater reuse===
In South Africa, the main driver for [[water reuse|wastewater reuse]] is drought conditions.<ref name="Meeker" /> For example, in [[Beaufort West]], South Africa's a direct wastewater reclamation plant (WRP) for the production of drinking water was constructed in the end of 2010, as a result of acute [[water scarcity]] (production of 2,300 m<sup>3</sup> per day).<ref>{{cite web|url=https://publications.lib.chalmers.se/records/fulltext/146252.pdf|title=Risk Assessment for South Africa's first direct wastewater reclamation system for drinking water production|access-date=29 July 2016}}</ref><ref>{{cite web|url=http://www.imesa.org.za/wp-content/uploads/2015/08/Paper-6.pdf|title=Beaufort West Water Reclamation Plant: First Direct (Toilet-to-Tap) Water Reclamation Plant in South Africa|access-date=29 July 2016|archive-date=13 September 2016|archive-url=https://web.archive.org/web/20160913233740/http://www.imesa.org.za/wp-content/uploads/2015/08/Paper-6.pdf|url-status=dead}}</ref> The process configuration based on multi-barrier concept and includes the following treatment processes: sand filtration, [[Ultrafiltration|UF]], two-stage [[Reverse osmosis|RO]], and permeate disinfected by [[ultraviolet light]] (UV).

The town [[George, Western Cape|George]] faced water shortages and had decided on an [[Reclaimed water#Planned potable reuse|IPR]] strategy (2009/2010), where final effluents from its Outeniqua WWTP are treated to a very high quality through UF and disinfection prior to being returned to the main storage facility, the Garden Route Dam, where they are combined with current raw water supplies. This initiative augments the existing supply by 10,000&nbsp;m<sup>3</sup> per day, approximately one third of the drinking water demand. The process configuration includes the following treatment processes: drum screen, UF, and chlorine disinfection. Provision has been made for powdered activated carbon (PAC) addition at George WTW, if required as an additional operational barrier.<ref name="Meeker">{{cite journal|last2=Meeker|first2=Melissa|last3=Minton|first3=Julie|last4=O'Donohue|first4=Mark|date=4 September 2015|title=International research agency perspectives on potable water reuse|journal=Environmental Science: Water Research & Technology|language=en|volume=1|issue=5|pages=563–580|doi=10.1039/C5EW00165J|issn=2053-1419|last1=Burgess|first1=Jo|url=https://zenodo.org/record/897658}}</ref>

Another example of DPR is the reuse plant constructed and operated in the town [[Hermanus]] (Overberg) in South Africa, where now 2,500&nbsp;m<sup>3</sup> per day of effluent reused, with a future plan to increase the capacity to 5,000&nbsp;m<sup>3</sup> per day. The treatment processes applied include UF pre-treatment, [[Desalination|RO desalination]], as well as [[Oxidation|advanced oxidation]] and [[carbon filtration]]. The product from the reuse plant is fed directly into the drinking water reticulation system.<ref name="Meeker" />