Water, Sewage & Effluent September-October 2017 | Page 26

An aerial view of the Walvis Bay WWTP showing the new trickling filter media [centre] and the existing stone-media [right]. Untapped water resources Water reuse technology is gaining traction against the backdrop of decreasing freshwater supplies and growing water demands, while entire South African communities struggle to access reliable, clean, disease-free drinking water. By Kim Kemp S outh Africa has limited freshwater resources and has been defined as water stressed by international standards, according to the Department of Water Affairs in annexure D of the National Water Resource Strategy (NWRS). The reuse of water in the country accounts for approximately 14% of total water use, and return flows account for a large part of water available for use from some of the important river systems. 24 Interest in the reuse of wastewater for non-drinking water requirements is also increasing, as industry intensifies and the severe drought spurs manufacturers and industry to find ways to augment municipal supplies with recycled, used, or wastewater. The NWRS (First Edition) identifies water reuse as one of several important strategies to find the delicate balance between water availability and water requirements. Water Sewage & Effluent September/October 2017 Vast potential exists for employing wastewater reuse for large non-potable applications, including landscape irrigation, industrial processes, and farming, specifically in arid areas of South Africa, especially the Western Cape province. However, there are a multitude of challenges that influence water access, apart from geological aspects and climatic influences, including the distance from a water source;