Allwright, AmyRidell, EddieRaubenheimer, Reinardt2018-08-202018-08-202018-01http://hdl.handle.net/11660/9146English: Continued population and economic growth within South Africa have led to increased water use by industry, agriculture, mining, domestic users and other uses over the past few decades. This increased usage has come close or even surpassed the threshold of renewable water resources within river basins. It was recognised that South Africa faces significant challenges in terms of water reform, involving major administrative and policy shifts, thus the attention has shifted to implementation. Water resource management has become of utmost importance to ensure that water users still receive an adequate supply, while at the same time the environmental flows are managed. Surface and groundwater processes have typically been studied as separate disciplines, regardless of their obvious association. They are both components of the hydrologic system however, they are not isolated components and interact in a range of climatic and physiographic landscapes. Thus, the contamination over usage or development of one affects the other. Consequently, a better understanding of the primary principles of the connectivity between the groundwater and surface water is essential for the successful management of water resources. This is particularly true upstream of the Kruger National Park, because of the limited understanding of groundwater – surface water interaction within catchments. This resulted in the initiation of this dissertation to determine the connectivity of geohydrological processes and the interaction with the surface hydrology of the Letaba River, to ultimately provide guidance for successful management of water resources. There are many techniques to measure groundwater – surface water interaction, although for this dissertation the following methods were implemented: hydraulic gradients, geological characterisation, aquifer characterisation, fluid logging, environmental tracer method and the chemical base flow separation method. All of the results were then incorporated to provide a final conceptual model, indicating the interaction between the geohydrology and hydrology of the Letaba River. The study site had to be divided into four transects, because of the scale. As anticipated, a simple losing or gaining stream was not indicated by the analyses. But, rather a complex system of groundwater movement and interaction with the surface hydrology for each transect, ultimately changing with seasonal variability and peak flow conditions. It has become clear through this research that the connectivity between the surface water and groundwater is extremely complex. Thus, indicating the importance of groundwater management to protect and provide sustainable development for both resources. Even though a good infrastructure for data capturing have been implemented certain gaps are still found. Further research and monitoring is essential to ultimately fully understand this complex interaction.Afrikaans: Voortgesette bevolking en ekonomiese groei binne Suid-Afrika het die afgelope paar dekades tot gevolg gehad dat water, nywerhede, landbou, mynbou, huishoudelike verbruik en ander gebruike toegeneem het. Hierdie verhoogde verbruik het naby die drempel van hernubare waterbronne in die rivier komme voorgekom of selfs oortref. Daar is verneem dat Suid-Afrika beduidende uitdagings in terme van water hervorming ondervind, met groot administratiewe en beleids verskuiwings en daarom het die aandag verskuif na implementering. Waterhulpbron bestuur het uiters belangrik geword om te verseker dat water verbruikers steeds voldoende toevoer kry, terwyl die omgewings vloei terselfdertyd bestuur word. Oppervlak- en groundwater prosesse is tipies as afsonderlike disiplinêre bestudeer, ongeag hul ooglopende assosiasie. Hulle is albei komponente van die hidrologiese stelsel, maar hulle is nie geïsoleerde komponente nie en wissel in verskillende klimaat- en fisiografiese landskappe. Dus, sal die besmetting, oor gebruik of ontwikkeling van die een die ander een beinvloed. Gevolglik is 'n beter begrip van die primêre beginsels van die verbindings tussen die groundwater en oppervlak water noodsaaklik vir die suksesvolle bestuur van waterhulpbronne. Dit geld veral vir die areas stroomop van die Nasionale Kruger wildtuin, weens die beperkte begrip van die groundwater – oppervlak water interaksie binne die opvangs gebiede. Dit het gelei tot die inisiëring van hierdie proefskrif om die konnektiwiteit van geohidrologiese prosesse en die interaksie met die oppervlak hidrologie van die Letaba rivier te bepaal, ten einde leiding te gee vir die suksesvolle bestuur van waterhulpbronne. Daar is baie tegnieke om groundwater – oppervlak water interaksie te meet, maar vir hierdie proefskrif is die volgende metodes geïmplementeer: hidroliese gradiënte, geologiese karakterisering, akwifer karakterisering, boorgat waterprofiele, "environmental tracer method" en die "chemical base flow separation" metode. Al die uitslae is dan opgeneem om 'n finale konseptuele model te verskaf, wat die wisselwerking tussen die geohidrologie en hidrologie van die Letaba - rivier aandui. Die studie area was in vier deursnitte verdeel, weens die skaal en omvang. Soos verwag, is 'n eenvoudige stroom wat water verloor of by kry, vanaf die grondwater sisteem nie deur die ontledings aangedui nie. Maar eerder 'n komplekse stelsel van grondwater beweging en interaksie met die oppervlak hidrologie vir elke deursnit, wat uiteindelik verander met seisoenale veranderlikheid en hoë vloei toestande. Uit hierdie navorsing het dit duidelik geword dat die verbinding tussen die oppervlak water en grondwater uiters kompleks is. Dus, dui dit op die belangrikheid van groundwater bestuur om volhoubare ontwikkeling vir beide bronne te beskerm en te voorsien. Selfs al is 'n goeie infrastruktuur vir data vaslegging geïmplementeer, word daar steeds sekere leemtes ondervind. Verdere navorsing en monitering is noodsaaklik om hierdie komplekse interaksie ten volle te verstaan.enEnvironmental changeSurface water interactionGroundwaterLetaba RiverAquiferDissertation (M.Sc. (Institute for Groundwater Studies))--University of the Free State, 2018DissertationUniversity of the Free State