Water resource management has become a pertinent issue of global environmental concern in response to the conditions of a growing global population, increasing development and a limited freshwater supply. It is against the backdrop of such conditions that effective water resource management has gained popularity in seeking to ensure that the needs of the growing population will be met and secured for future generations. The notion of integrated water resource management (IWRM) is a perspective on water resource management that has evolved out of the global opinion that social and ecological systems are linked and therefore cannot be managed separately. The department of water affairs (DWA) in South Africa highlights the importance of approaching management of water resources from a catchment perspective which forms the basis for a particular integrated approach to management called integrated catchment management (ICM). ICM recognizes the catchment as the correct administrative unit for management. It integrates water resources and the land that forms the catchment area in planning and management. Researchers have described the implementation of ICM as being complicated and difficult. This is no exception to South Africa. Principles of ICM have received widespread prominence in South Africa as they have been incorporated into national water policy. Actual implementation however is still in its infancy. The study is therefore a case study of ICM with respect to factors influencing implementation amongst different stakeholders. The study aims to explore the theme of implementation of ICM within the context of the Gamtoos River Catchment with a view toward identifying and addressing challenges that may be more broadly applicable. The study adopts an inductive, exploratory approach to the connection between theory and practice. A systems-based framework characterized by sequential steps similar to that employed in a case study conducted by Bellamy et al. (2001) in Queensland Australia is used to facilitate the evaluation of ICM in the Gamtoos River Catchment. The evaluation is achieved through a three step process of exploration in the current study. Triangulation is applied to the choice of methods of analysis which involves the use of a global analysis method, the use of learning scenarios and a grounded theory method. Findings reveal seven core themes which help to provide a detailed, contextual understanding relating to the status quo for ICM in the catchment. Results from a grounded theory analysis summarized the main challenges to implementation into five broad categories. Based on this analysis method and the application of the three learning scenarios for the Gamtoos River Catchment, the extent to which these challenges exist was discovered. The state of ICM in the catchment was classified as falling within a condition of a level of success being achieved with room for improvement to a condition of optimal ICM. The study concludes that based on the context of ICM being an example of a Complex Adaptive Systems (CAS), this state of ICM in the Gamtoos River Catchment is subject to change. This therefore necessitates the consideration of approaches to implementation that are adaptive to change. Findings may serve to inform decision making on how ICM can be effectively implemented elsewhere in a South African context.

In water resources management in South Africa, there is an emphasis on public participation. On a river catchment basis, one of the mechanisms for such participation is the establishment of catchment forums. However, members of catchment forums, particularly those coming from poor or rural communities, cannot be expected to engage in catchment management without having been enabled to do so. This thesis considers the use of GIS in the process of enabling the Kat River Valley Catchment Forum to better participate in catchment management. The research focus is on the use of GIS to facilitate an understanding of the Kat River Catchment and associated catchment concepts, and constructive communication and sharing, among the Catchment Forum. The GIS is used in the context of "GIS for Participatory Research", an outgrowth of Public Participation GIS (PPGIS), which focuses on GIS as a tool for empowerment within participatory processes. The study has used Action Research, situated in the Critical paradigm, as a methodology. The research has included seven Forum workshop processes and one series of in-village meetings. These engagements have involved map-based appraisals, issues and resource mapping, map-based planning, and the use of on-screen GIS for presentation and sharing. The use of GIS has facilitated the creation of customised maps, the integration of village-scale mapping into a catchment scale product, the presentation of synthesised data in digital and hardcopy format and, in so doing, has allowed catchment-scale appraisal. Outcomes enabling participation in catchment management have included developed mapping skills and an enhanced understanding of the catchment as a whole, and developed conceptual access to a decision-making language (or way of thinking), among participants. Furthermore, the Forum as a whole has identified common needs, and has developed a set of map-based action plans. The research process has yielded a number of lessons regarding "GIS for participation" and the participatory framework within which it takes place. Chief among these is that the GIS operator should take on the role of a participatory practitioner.

Sedimentation has become a significant environmental threat in South Africa as it intensifies water management problems in the water-scarce semi-arid regions of the country. As South Africa already allocates 98% of available water, the loss of storage capacity in reservoirs and degraded water quality has meant that a reliable water supply is compromised. The overall aim of this thesis was to develop a catchment scale model that represents the sediment dynamics of semi-arid regions of South Africa as a simple and practically applicable tool for water resource managers. Development of a conceptual framework for the model relied on an understanding of both the sediment dynamics of South African catchments and applicable modelling techniques. Scale was an issue in both cases as most of our understanding of the physical processes of runoff generation and sediment transport has been derived from plot scale studies. By identifying defining properties of semi-arid catchments it was possible to consider how temporal and spatial properties at higher levels emerged from properties at lower levels. These properties were effectively represented by using the Pitman rainfall-runoff model disaggregated to a daily timescale, the Modified Universal Soil Loss Equation (MUSLE) model incorporating probability function theory and through the representation of sediment storages across a semi-distributed catchment. The model was tested on two small and one large study catchment in the Karoo, South Africa, with limited observed data. Limitations to the model were found to be the large parameter data set and the dominance of structural constraints with an increase in catchment size. The next steps in model development will require a reduction of the parameter data set and an inclusion of an in-stream component for sub-catchments at a larger spatial scale. The model is applicable in areas such as South Africa where water resource managers need a simple model at the catchment scale in order to make decisions. This type of model provides a simple representation of the stochastic nature of erosion and sediment delivery over large spatial and temporal scales.

Submitted in fulfillment of the requirements of the degree of Doctor of Engineering: Civil Engineering, Durban University of Technology. Durban. South Africa, 2015. / The planning and management of water resources systems often involve formulation and establishment of optimal operating policies and the study of trade-off between different objectives. Due to the intricate nature of water resources management tasks, several models with varying degrees of complexities have been developed and applied for resolving water resources optimisation and allocation problems. Nevertheless, there still exist uncertainties about finding a generally consistent and trustworthy method that can find solutions which are very close to the global optimum in all scenarios. This study presents the development and application of a new evolutionary multi-objective optimisation algorithm, combined Pareto multi-objective differential evolution (CPMDE). The algorithm combines methods of Pareto ranking and Pareto dominance selections to implement a novel generational selection scheme. The new scheme provides a systematic approach for controlling elitism of the population which results in the simultaneous creation of short solution vectors that are suitable for local search and long vectors suitable for global search. By incorporating combined Pareto procedures, CPMDE is able to adaptively balance exploitation of non-dominated solutions found with exploration of the search space. Thus, it is able to escape all local optima and converge to the global Pareto-optimal front. The performance of CPMDE was compared with 14 state-of-the-art evolutionary multi-objective optimisation algorithms. A total of ten test problems and three real world problems were considered in the benchmark of the algorithm. Findings suggest that the new algorithm presents an improvement in convergence to global Pareto-optimal fronts especially on deceptive multi-modal functions where CPMDE clearly outperformed all other algorithms in convergence and diversity. The convergence metric on this problem was several orders of magnitude better than those of the other algorithms. Competitive results obtained from the benchmark of CPMDE suggest that it is a good alternative for solving real multi-objective optimisation problems. Also, values of a variance statistics further indicate that CPMDE is reliable and stable in finding solutions and converging to Pareto-optimal fronts in multi-objective optimisation problems. CPMDE was applied to resolve water allocation problems in the Orange River catchment in South Africa. Results obtained from the applications of CPMDE suggest it represents an improvement over some existing methods. CPMDE was applied to resolve water allocation problems in the agricultural and power sectors in South Africa. These sectors are strategic in forging economic growth, sustaining technological developments and contributing further to the overall development of the nation. They are also germane in capacitating the South African government’s commitment towards equity and poverty eradication and ensuring food security. Harnessing more hydropower from existing water sources within the frontier of the country is germane in capacitating the South African Government’s commitment to reduction of the countries’ greenhouse gas emissions and transition to a low-carbon economy while meeting a national target of 3 725 megawatts by 2030. Application of CPMDE algorithm in the behavioural analysis of the Vanderkloof reservoir showed an increase of 20 310 MWH in energy generation corresponding to a 3.2 percent increase. On analysis of storage trajectories over the operating period, it was found that the real time analysis incorporating a hybrid between CPMDE and ANN offers a procedure with a high ability to minimize deviation from target storage under the prevailing water stress condition. Overall, the real time analysis provides an improvement of 49.32 percent over the current practice. Further analysis involving starting the simulation with a proposed higher storage volume suggests that 728.53 GWH of annual energy may be generated from the reservoir under medium flow condition without system failure as opposed to 629 GWH produced from current practice. This corresponds to a 13.66 percent increase in energy generation. It was however noted that the water resources of the dam is not in excess. The water in the dam is just enough to meet all current demands. This calls for proper management policies for future operation of the reservoir to guard against excessive storage depletions. The study herein also involved the development of a decision support system for the daily operation of the Vanderkloof reservoir. This provides a low cost solution methodology suitable for the sustainable operation of the Vanderkloof dam in South Africa. Adopting real time optimisation strategies may be beneficial to the operation of reservoirs. Findings from the study herein indicate that the new algorithm represents an improvement over existing methods. Therefore, CPMDE presents a new tool that nations can adapt for the proper management of water resources towards the overall prosperity of their populace. / D

Thesis (MA)--Stellenbosch, 2004. / ENGLISH ABSTRACT: South Africa is a semi-arid country with an average annual rainfall of 197mm, in comparison with the international average of 860mm per year, of which the available freshwater sources are currently being utilised virtually completely. The water restrictions in the Western Cape during the summer of 2000/2001 and of 2001/2002 are sufficient evidence of this. This threatening water shortage holds far-reaching consequences for the socio-economic development of the country if an active effort is not made to manage the water resources in a sustainable manner. Starting in the 1990s, the concept of integrated catchment management crCM) began to enjoy widespread attention as a mechanism to manage water resources. However, it was primarily forced, state-initiated projects with little direct community involvement that enjoyed a limited amount of success. This study undertook community-driven, integrated catchment management in a relatively small catchment in the Veldwachters River valley in the Stellenbosch area in the Western Cape in order to investigate the effectiveness thereof as a mechanism for sustainable water resource management. The study firstly places the concept of rCM in perspective, after which the study area is demarcated spatially within the South African and the regional context. Community-based action research as research approach provides the techniques to reconcile and integrate the duality of the rCM process, namely the human and physical elements in a catchment, and to successfully involve the community in the process. The first phase of the study entails the gathering of existing and new information and the definition of the environmental status of the catchment area in a situation analysis, which was presented to the community as an information document to initiate public participation. During the second phase, a community partnership was established by means of introductory interviews, correspondence, focus group meetings and public forums. The third and executive phase was characterised by the mobilisation of the community partnership in the execution of strategic planning procedures, such as the formulation of a catchment vision, prioritisation of relevant catchment management issues, the statement of the management objectives and the formulation and implementation of action plans for the management of various issues in the catchment. The conclusion drawn after a thorough evaluation of the course of the study is that the implementation of community-driven integrated catchment management can be successful ina smaller catchment. A few crucial requirements need to be taken into consideration in future applications elsewhere, namely: • That the study area must have a small enough area so that all stakeholders can be involved relatively easily and for a catchment identity and "ownership" of the process to be able to develop; • That the process must initially be facilitated externally until a community partnership has been established and a management committee has been elected, after which the facilitation and management of the process must be handed to the community so that it can finally become completely community driven; • That socio-econornic issues initially will receive more attention than the natural environment, but that these issues need to be utilised to establish the ICM process, after which the natural environment naturally will receive greater priority; and • That the researcher must remain patient, particularly during the second and third phases of the process, as public participation and particularly the establishment of a community-driven process can be slow and exhausting. This case study emphasises that each application of ICM will be unique because the degree of community involvement and the priorities of catchment communities will differ. Communitydriven integrated catchment management is not, under any circumstances, an instant solution for water management and water conservation issues, but it is the only sustainable option. KEY WORDS: catchment management, public/community participation, situation analysis, water resource management, action research. / AFRIKAANSE OPSOMMING: Suid-Afrika is 'n semi-ariede land met 'n gemiddelde reenvalsyfer van 497mm per jaar teenoor die wereldgemiddelde van 860mm per jaar, waarvan beskikbare varswaterbronne tans byna ten volle benut word. Die waterbeperkings in die Wes-Kaap gedurende die somers van 2000/2001 en 200112002 is afdoende bewys hiervan. Hierdie dreigende watemood hou verreikende gevolge vir die sosio-ekonomiese ontwikkeling van die land in, indien daar nie 'n daadwerklike poging aangewend gaan word om die waterhulpbronne volhoubaar te bestuur nie. Sedert die negentigerjare het die konsep van geintegreerde opvanggebiedbestuur (GOGB) as waterhulpbronbestuursmeganisme wye belangstelling begin geniet. Dit was hoofsaaklik afgedwonge, staatsgeinisieerde projekte met min direkte gemeenskapsbetrokkenheid wat beperkte sukses gehad het. Hierdie studie het 'n gemeenskapsgedrewe geintegreerde opvanggebiedbestuur op 'n relatief klein opvanggebied in die Veldwachtersrivier vallei in die Stellenbosch omgewing in die Wes-Kaap ondemeem, ten einde die effektiwiteit daarvan as 'n volhoubare waterhulpbron-bestuursmeganisme te ondersoek. Die studie plaas eerstens die konsep van GOGB in perspektief, waama die studiegebied ruimtelik binne die Suid-Afrikaanse en streekskonteks afgebaken word. Gemeenskapsgebaseerde aksienavorsing as navorsingsbenadering verskaf die tegnieke om die tweeledigheid van die GOGB proses, naamlik menslike en fisiese elemente in 'n opvanggebied, te verso en en te integreer en om die gemeenskap suksesvol by die proses te betrek. Die eerste fase van die studie behels die insameling van bestaande en nuwe inligting en die ornskrywing van die omgewingstatus van die opvanggebied in 'n situasie-analise, wat as inligtingsdokurnent aan die gemeenskap voorgele word om publieke deelname te inisieer. Gedurende die tweede fase is 'n gemeenskapsvennootskap gevestig met behulp van inleidende onderhoude, korrespondensie, fokusgroepbyeenkomste en pub Iieke forums. Die derde en uitvoerende lase is gekenmerk deur die mobilisering van die gemeenskapsvennootskap m die uitvoering van strategiese beplanningsprosedures soos die formulering van 'n opvanggebiedvisie, prioritisering van tersaaklike opvanggebiedkwessies, bestuursdoelwitstelling en die formulering en implementering van aksieplanne vir die bestuur van verskeie kwessies in die opvanggebied. Die gevolgtrekking na die noukeurige evaluering van die verloop van hierdie studie, is dat die implementering van gemeenskapsgedrewe gemtegreerde opvanggebiedbestuur in 'n kleiner opvanggebied wel suksesvol kan wees. 'n Paar beslissende vereistes moet met toekomstige toepassings elders in ag geneem word, naamIik: • Dat die studiegebied oppervlakgewys klein genoeg moet wees sodat alle rolspelers relatief maklik betrek kan word en 'n opvanggebied-identiteit en "eienaarskap" van die proses kan ontwikkel; • Die proses moet aanvanklik ekstem fasiliteer word, totdat 'n gemeenskapsvennootskap gevestig is en 'n bestuurskomitee verkies is, waama die fasilitering en bestuur van die proses aan die gemeenskap oorgegee moet word om uiteindelik ten volle gemeenskapsgedrewe te word; • Dat sosio-ekonomiese kwessies aanvanklik aandag b6 die natuurlike omgewing sal geniet, maar dat hierdie kwessies benut moet word om die GOGB proses te vestig, waama die natuurlike omgewing vanselfsprekend hoer prioriteit sal geniet; en • Dat die navorser veral gedurende die tweede en derde fases van die proses geduld moet behou, omdat publieke deelname en veral die vestiging van 'n gemeenskapsgedrewe proses, tydsaam en vermoeiend kan wees. Hierdie gevallestudie beklemtoon dat elke toepassing van GOGB uniek sal wees omdat die mate van gemeenskapsdeelname en -prioriteite tussen opvanggebiedgemeenskappe sal verskil. Gemeenskapsgedrewe gemtegreerde opvanggebiedbestuur is onder geen ornstandighede 'n kitsoplossing vir waterbestuur en -bewaring nie, maar dit is die enigste volhoubare opsie. SLEUTEL WOORDE: opvanggebiedbestuur, publieke/gemeenskapsdeelname, situasie-analise, waterhulpbronbestuur, aksienavorsing

Thesis (MSc)--University of Stellenbosch, 2005. / ENGLISH ABSTRACT: Invasive alien trees, especially Acacia species, are a great threat to biodiversity in South African rivers. The national Working for Water Programme is addressing the alien problem by removing alien trees from river margins. The concern is that this may be creating even further disturbance by affecting water quality and habitats. In particular, how is this affecting rare and endemic species? Benthic macro invertebrates and aerial odonates were assessed along five Western Cape rivers in alien-invaded, cleared and natural sites between December and March. The aim was to assess the effect of both alien invasion and alien clearing on aquatic invertebrates. Odonata, being easily sampled, were also assessed as they are severely affected by the lack of understorey plants in shaded, alien-invaded sites. Odonata and benthic macroinvertebrates were treated as two separate studies and no attempt was made to correlate the results obtained from both studies. SASS5, a qualitative, rapid bioassessment technique, based on the sensitivity of the families present, was used as a measure of river health and, indirectly, of water quality. SASS indicated a decline in water quality conditions after alien clearing, a likely response to the greater insolation as well as erosion of cleared banks, resulting in elevated temperatures and suspended solids and lowered oxygen levels. Community responses to alien disturbance and other environmental factors were analysed using PRIMER and CANOCO software. Assemblages of Odonata were found to provide a rapid, cost-effective means of assessment and monitoring. Potential indicator and detector species were also identified using the lndicator Value method. Assemblage patterns of aquatic invertebrates, however, were dominated by between-river and seasonal effects. Therefore, while SASS detected overall changes in river health, without identifying the cause, potential aquatic detector taxa were identified that may be useful for linking general disturbance to alien invasion or clearing. All indicator and detector taxa identified in both studies can be used for long-term monitoring and for identifying biodiverse areas for clearing or protection. In both studies, sensitive, endemic taxa were lost after clearing, being replaced by more tolerant, widespread taxa. Recovery of the biota appears to follow the recovery succession of the vegetation, with most sensitive or endemic taxa only appearing after the recovery of indigenous plants. A number of recommendations are made regarding the restoration of both water quality (particularly with respect to shade and soil erosion) and biotope availability (particularly in terms of the recultivation of indigenous plants) in order to achieve biodiversity objectives. The role of catchment management, prioritisation procedures and long-term monitoring are also discussed. / AFRIKAANSE OPSOMMING: Uitheemse, indringerbome, veral Acacia spesies, is 'n groot bedreiging vir biodiversiteit in Suid- Afrikaanse riviere. Die nasionale Werk vir Water-projek spreek hierdie probleem aan deur uitheemse bome van rivieroewers te verwyder. Die kommer is dat water kwaliteit en habitatte sodoende verder versteur kan word. Byvoorbeeld, hoe word endemiese en bedreigde spesies geraak? Akwatiese makroinvertebrate en volwasse Odonata in vyf Wes-Kaapse riviere is tussen Desember en Maart bestudeer en gemonster in natuurlike gebiede, in gebiede waar indringerbome teenwoordig is, en in gebiede waar hulle verwyder is. Die doel was om die effek van indringerverwante impakte op akwatiese invertebrate vas te stel. Odonata is ook bestudeer omdat hulle maklik gemonster kan word en omdat hulle ernstig geraak word deur indringers. Die uitheemse plantegroei oorskadu die oewers en verhoed die groei van inheemse oewerplante. Die bentiese makro-invertebrate en Odonata is as twee aparte studies behandel en geen poging is gemaak om die resultate van die twee te vergelyk nie. SASSS, 'n kwalitatiewe, bioasseseringsmetode wat op die sensitiwiteit van die aanwesige families baseer word, is gebruik om waterkwaliteit op 'n indirekte manier te bepaal. SASS het aangedui dat daar 'n afname in waterkwaliteit is nadat indringerplante verwyder is. Dit is moontlik as 'n gevolg van groter blootstelling aan sonskyn en erosie van rivieroewers wat veroorsaak dat temperature en die hoeveelheid gesuspendeerde materiaal verhoog word, en dat suurstof konsentrasies verminder word. Die gevolge van indringerplante en ander omgewingsfaktore op akwatiese gemeenskappe is met PRlMER en CANOCO sagteware ontleed. Groepering van Odonata kan gebruik word om op 'n maklike en koste-effektiewe manier om die impak van indringerplante en hul verwydering te bepaal en te monitor. Aanwyserspesies is ook deur middel van die 'Indicator Value' metode geïdentifiseer. Die verspreidingspatrone van invertebraatspesies word deur geografiese en seisoenale effekte oorheers. Dus, terwyl SASS veranderinge in waterkwaliteit kan aantoon, sonder om die oorsaak daarvan te identifiseer, kan aanwyserspesies gebruik word om meer spesifieke impakte deur indringerplantegroei, of indringerverwydering, te bepaal en te monitor. Hulle kan ook gebruik word om gebiede met hoë biodiversiteit vir bewaring of indringerverwydering te identifiseer. Beide studies dui aan dat sensitiewe en endemiese taksa na indringerverwydering verlore gaan, en vervang word met meer geharde, wydverspreide taksa. Herstel van die biota volg op die herstel van die plant gemeenskappe, en die mees sensitiewe of endemiese taksa herstel eers nadat die inheemse plantegroei herstel het. 'n Aantal aanbevelings in verband met die restorasie van waterkwaliteit (veral in terme van die hoeveelheid skaduwee en erosie) en die beskikbaarheid van biotope (veral in terme van inheemse plante) om biodiversiteitsdoelwitte te bereik word gemaak. Die rol van opvanggebied bestuur, voorrang prosedures en lang termyn monitering word ook bespreek.

Thesis (MA (Geography and Environmental Studies))--University of Stellenbosch, 2005. / River basins have long been attracting human settlement and development, promising water and fertile lands (Newson 1992). The Bot River Catchment on the southern coast of South Africa is no exception. However, much of the development in this catchment has not been controlled and its land and water resources are being abused. This is affecting the water quality and quantity of the river system and estuary at an alarming rate. In this thesis, the ‘reference’ land cover in the Bot River Catchment is recreated. This term is used to describe “the hydrological state of the catchment as it was when completely covered in natural vegetation, thus before it was impacted by humans” (Jacobs & Bruwer 2002:12). A rainfall-runoff model is employed to investigate the effects of various land covers on the catchment’s runoff quantity, by comparing the simulation results of the catchment’s reference and current state. The results of the model point to a large reduction in runoff since the reference state of the catchment. As the rainfall-runoff model applied did not allow for modelling of the annual agriculture that dominates the catchment, the runoff reduction was attributed to the smaller areas of perennial agriculture, forestry and alien vegetation infestation. The simulation results confirmed the threat of current land use practices on the environmental integrity of the Bot River Catchment. A transition to agricultural practices that are more suited to the climate is suggested and the eradication of alien vegetation should be seen as a priority. Most importantly, a holistic approach should be taken towards the management of the Bot River Catchment. The altered hydrodynamic regime of the Bot River Estuary is symptomatic of misuse of the entire catchment. As ongoing demographic and land use pressures create a new generation of water management problems (Department of Water Affairs & Forestry 1993), a deeper understanding of the relationships between the different components in the Bot River Catchment becomes increasingly urgent.

South Africa's water resources are unequally distributed over space and time to a high degree and our already stressed water resources situation will only be exacerbated by climate change if current predictions are correct. The potential for conflict over increasingly strained water resources in South Africa is thus very real. In order to deal with these complex problems national legislation is demanding that water resource management be decentralized to the local level where active participation can take place in an integrated manner in accordance with the principles of IWRM. However, administrative and political boundaries rarely match those of catchments as, throughout South Africa, rivers have been employed extensively to delineate administrative and political boundaries at a number of spatial scales. The aim of this research is to determine if rivers act as dividing or uniting features in a socio-political landscape and whether topography will influence their role in this context. By considering sections of the Orange-Senqu River, some of which are employed as political or administrative boundaries, this project furthermore aims to consider the implications of this for catchment management in South Africa. South Africa's proposed form of decentralized water management will have to contend with the effects of different topographies on the way in which rivers are perceived and utilized. The ability of a river to act as a dividing or uniting feature is dependent on a number of interrelated factors, the effects of which are either reduced or enhanced by the topography surrounding the river. Factors such as the state of the resource, levels of utilization, local histories and the employment of the river as a political or administrative border are all factors that determine the extent to which a river unites or divides the communities along its banks, and are all influenced by topography. The implications of this for the management of catchments in South Africa are significant. Local water management institutions will have to contend with a mismatch in borders and in many cases bridge social divides that are deeply entrenched along the banks of rivers. Importantly, the need for a context specific approach to catchment management is highlighted.