Water, Sewage & Effluent July-August 2017 | Page 18

Groundwater as an option Water supply is severely under scrutiny as South Africa recovers from the aftermath of terrible droughts while attempting to meet ever-growing demand. By Matthys Dippenaar (PhD, PrSciNat) I n the light of the severe water shortages, (often uninformed) opinions about mine water decant, hydraulic fracturing, and governance, to name a few, are compromising our objectivity to consider sustainable sources of water beyond the conventional capture of surface water. International research is developing rapidly towards alternative sources for water supply. Fog harvesting, artificial groundwater recharge, urban supply from groundwater, and desalinisation are increasingly being accepted worldwide as supplement to water supply and as sole supply options to cities, peri-urban areas, and rural developments. For some reason, South Africa has not yet bought into the option of utilising aquifers. Pretoria was supplied with spring water for the first 75 years of its founding. To this day, the same dolomitic springs supply almost 8% of the water requirements of the City of Tshwane (which has since increased significantly in land surface and population), amounting to almost 60 million litres per day. The City of Cape Town was also initially supplied by springs, although 16 water from these springs is now discharged via underground tunnels to the ocean, owing to increasing contamination resulting from rapid urbanisation. However, Cape Town has successfully implemented and managed the first (and presently only) groundwater recharge scheme in South Africa, where water is stored in the sand deposits in Atlantis. Numerous other cities and smaller towns are dependent on groundwater; yet, groundwater sustainability is still queried. Trust issues While it is understandable that rapid development resulted in significant water imports to metropolitan regions, we seem to have lost our trust in groundwater. Groundwater is essential to supplemen