Civil Engineering March 2022 | Vol 30 No 2

Civil Engineering March 2022 53 pipes are quicker and easier to install, have lower failure rates, are less suscep- tible to corrosion, experience fewer joint leaks and are lower in price. Municipalities should spend the money allocated in their budgets to upgrade and replace old and failing water infrastructure without delay. This will place us in the position to save enough purified water to significantly reduce the impact and long-term effects of our below average rainfall and avoid the threat of “water shedding” in the months to come.  REFEReNCE UN Water. SDG 6 Data Portal. Available: https://www.sdg6data.org . Figure 1 Fresh water withdrawal as a proportion of available fresh water resources in South Africa (compared to other countries in the sub- Saharan region) Freshwater withdrawal as a proportion of available freshwater resources (%) Burundi Côte d'Ivoire Ethiopia Ghana Kenya Mali Mauritania Mauritius Malawi Réunion Somalia Eswatini Chad Togo Uganda Zimbabwe South Africa 6.4.2 Level of water stress: freshwater withdrawal as a proportion of available freshwater resources* in South Africa, change ​over time, compared to other countries (and areas) in the region In the below chart, the value of South Africa is displayed in accent colour. The values of the following countries (or areas) in the same region are displayed in grey: Angola, Burundi, Benin, Burkina Faso, Botswana, ​Central African Republic, Côte d'Ivoire, Cameroon, Democratic Republic of the Congo, Congo, Comoros, Cabo Verde, Djibouti, Eritrea, Ethiopia, Gabon, Ghana, Guinea, Gambia, Guinea-Bissau, Equatorial Guinea, Kenya, ​Liberia, Lesotho, Madagascar, Mali, Mozambique, Mauritania, Mauritius, Malawi, Namibia, Niger, Nigeria, Réunion, Rwanda, Senegal, Sierra Leone, Somalia, South Sudan, Sao Tome and Principe, Eswatini, Chad, Togo, ​United Republic of Tanzania, Uganda, Zambia, Zimbabwe​ Data provider: FAO ​Exported from UN-Water https://www.sdg6data.org on 10 January 2022 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 0 10 20 30 40 50 60 70 80 90 The ground is always subject to movement - slowly over a number of years due to settlement, or rapidly due to external events such as floods, temperature fluctuations, earthquakes and sinkholes. FLEXIBILITY IS STRENGTH Invest in good quality plastic pipes bearing the SAPPMA mark of quality for peace of mind. These pipes have been locally produced and manufacturers undergo regular, independent auditing to confirm they meet stringent local and international standards. When the pipes reach their end-of-life as water and sewer systems after 100+ years, it can be recycled and thereby play an important role in contributing to the circular economy. Visit www.sappma.co.za for more information. BEING FLEXIBLE, PLASTIC PIPES ARE EMINENTLY SUITABLE IN • poor soil conditions • fluctuating temperatures • earthquakes • areas subject to sinkholes It is vital for buried pipes to have an element of flexibility. Rigid pipes that do not flex are unable to accommodate changing ground conditions and are likely to crack, split or become disjointed. Gaps formed at the pipe joints compromise flow performance and allow leakage.As soon as that happens, those pipes are no longer performing as intended, but in fact are failures*. Plastic pipes are inherently flexible and therefore perform very well when the subsoil moves. * https://www.teppfa.eu/DynamicGroundMovementsReport