Civil Engineering March 2022 | Vol 30 No 2

50 March 2022 Civil Engineering wATER eNG I NEER I NG A core focus of World Water Day is to inspire action towards Sustainable Development Goal (SDG) 6: water and sanitation for all by 2030. This year’s theme, “Groundwater – making the invisible visible” highlights the importance of an often unrecognised but vitally important resource. A RESOURCE UNDER THREAT According to UN-Water, almost all of the liquid freshwater in the world is ground- water. However, groundwater resources are facing pollution and over-abstraction in many places. An estimated 40% of the water used for irrigation globally comes from aquifers. This is particularly the case in water-scarce countries and regions, where over-abstraction can lead to groundwater depletion. Groundwater pollution is a particular problem that can take decades or even centuries to recover from. The potential threats to groundwater quality are natural (geogenic) and human (anthropogenic) contamination. Two of the most widespread geogenic contaminants are arsenic and fluoride. Naturally occurring arsenic pollution in groundwater affects millions of people globally and necessitates better and more regular assessment and monitoring of groundwater. Anthropogenic contamination includes the effects of agricultural intensification, urbanisation, population growth and cli- mate change. Across Africa, groundwater quality is affected by poor sanitation infra- structure and agriculture practices, which has led to high levels of nitrate and mi- crobial contamination. In North America and Europe, nitrates and pesticides are a major threat. In fact, 20% of groundwater bodies in the European Union (EU) exceed EU standards on good water quality due to agricultural pollution. In another places, the extent of avail- able groundwater is not known, which means we could be failing to harness a potentially vital water resource. PROTECTING GROUNDWATER Exploring, protecting and sustainably using groundwater will be central to adapting to climate change and meeting the needs of a growing population. UN-Water asserts that coherent policies on energy, land use and irrigation are vital to avoiding groundwater depletion. 53 of the SDG’s 169 targets have a link to groundwater. These include SDG target 2.4 for sustainable food production sys- tems and resilient agricultural practices, SDG target 6.6 to protect and restore water-related ecosystems, and SDG target 15.1 on the conservation of freshwater ecosystems and their services. To assist with better groundwater management, a catalogue on groundwater management and governance tools, meas- ures and instruments is being developed and will be introduced during the UN- Water Groundwater Summit in December 2022. The catalogue will be accompanied by a set of international case profiles exhib- iting exemplary practice. The publication will be made available in a wiki format, allowing for easy access and update. Source www.worldwaterday.org World Water Day – making the invisible visible On 22 March each year, the world commemorates World Water Day to celebrate water and raise awareness of the 2 billion people currently living without access to safe water. South Africa’s annual National Water Week coincides with the international event to raise awareness of local water and sanitation issues.