Please read the abstract in the section 00front of this document / Thesis (PhD (Water Utilisation))--University of Pretoria, 2005. / Civil Engineering / unrestricted

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published_or_final_version / Environmental Management / Master / Master of Science in Environmental Management

This study proposes a framework for measuring and explaining partnership formation and resilience. The motivation for this study is that we currently do not understand the precise mechanism by which partnerships form or how they stay together in the face of change. The framework draws on a design view of systems to argue that partnerships manage change through boundary spanning practices that operate on multiple levels of social reality. The literature suggests that there are many different types of boundary spanning practices. Some types foster social-technical innovations called "boundary objects" while others facilitate the progressive standardization of those practices through the comparison and selection of boundary objects by social actors who are themselves transformed by their adoption of these objects. The framework proposes a way to measure partnership capacity and social learning that corresponds to the orders of boundary spanning practices. It furthermore proposes three hypotheses, one concerned with partnership formation and two concerned with resilience. The first hypothesis states that partnerships form through a convergence of boundary spanning practices and a community of practice. Convergence depends on a host of factors, including the capacity of innovators and early adopters to leverage their early successes to build additional capital to further promote and eventually institutionalize their boundary spanning practices. The second hypothesis predicts that partnerships that demonstrate a pattern of alignment practices integrating operational and strategic concerns will tend to oscillate within a defined range of partnership functions or "states" (restricted resilience). The third hypothesis predicts that partnerships that inculcate a learning culture of institutional design practices will tend to persist under a theoretically limitless range of environmental demands (general resilience). To assess the framework, four case studies of water resource management partnerships in the Columbia River Basin were carried out. Data collection centered on interviews with boundary spanners, field trips, and secondary data. The results partially confirmed the first hypothesis, while evaluations of the resilience hypotheses were inconclusive. However, boundary spanning practices were catalogued according to the various types of partnership processes to demonstrate how the methodology can be used for cross-case comparisons and theory-building.

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A research report submitted to the Faculty of Science, in partial fulfilment of the requirements for the degree of Master of Science in Hydrogeology, School of Geosciences, University of the Witwatersrand. Johannesburg, June 2017. / Groundwater is a principal source of water for many semi-arid countries, including Botswana and South Africa. This is especially true for the rural communities within these regions that lie on the periphery of local water scheme pipelines and make direct use of groundwater. The Ramotswa transboundary aquifer, which supplies local communities and nearby cities with fresh groundwater, is a highly productive and unique karst sequence shared by South Africa and Botswana. The objective of the study was to contribute to the available hydrogeological data by means of evaluating groundwater flow, nitrate pollution and the median recession index and master recession curve for the aquifer. The interpreted airborne geophysical data revealed the presence of collapsed features in the northeastern area corresponding to the karst morphology. A piezometric map of the area shows the groundwater flow is towards the north-northeast, which is supported by salinity increase across the study area. Increased nitrate concentrations were identified in areas with increased rainfall, shallow groundwater and a mature karst system. Only 3% of the 36 sample sites had nitrate concentrations exceeding the WHO guideline limit of 50 mg/l. This was attributed to the legacy of unlined pit latrines in karstified areas. Pollution is entirely anthropogenic and generally from non-point sources. A median recession index computed by RECESS program from the Dinokana spring discharge data was 295.7 days per log cycle and the generated master recession curve’s gentle slope alludes to massive storage potential within the karst compartment. The results of the study can alert stakeholders alike of the health risk of direct consumption of the groundwater without pretreatment. Establishing an understanding of the nitrate pollution sources and groundwater flow direction, and estimating the recession index provides informed groundwater pollution and vulnerability management options. This can improve the aquifer resource assessment and the livelihoods of local communities in the face of increasing climate change. / XL2017

Sappi's Ngodwana integrated Kraft pulp and paper mill was used as case study for the application and evaluation of the water pinch technique. The technique of water pinch originates from energy pinch, but uses mass flow and contaminant concentration to identify water and effluent reduction opportunities. The classical meaning of pinch, as defmed by energy pinch has however been changed to a more modem meaning. Historically the terms water or energy pinch was used to refer to the points where two composite curves touched on energy or water graphs. This graphical meaning of pinch is gradually being replaced to refer to the optimal po int proposed by a numerical solver beyond which improvement of the water network is no longer possible for the given inputs. The water pinch technique was applied by means of a numerical solver that used mixed integer non-linear programming to optimise to the minimum cost for running the water network under investigation. The problem defmition was defined in terms of costs associated with the use of utilities, raw material, treatment facilities and process units. It was also possible to define factors such as environmental impact, corrosion, fouling, scaling, cooling tower treatment cost, legal risk etc in terms of a penalty cost. The water pinch technique has been refined in software packages that are user friendly, ca~ble of handling multi-contaminants and suitable for varying flows. The software package WaterPinch by Linnhoff March was used. The case study was applied on Ngodwana mill that has an already highly closed water system with effluent generation rates as low 20 kL per ton of pulp and paper. The pinch study included sodium, chloride, calcium, suspended solids and COD as contaminants. The study investigated different applications of the pinch technique. The following was concluded: • The mill's understanding of its current restrictions, ()l pinch points, of its water network was confirmed. No new pinch points have been identified of which the mill was not aware. This indicates that the mill was already highly knowledgeable about its water system. This was expected of a mill that has a very low specific-effluent-generation rate. Water pinch was unable to significantly improve on the effluent generation rate of the mill. • The pinch analysis has identified opportunities of mixing small quantities of waste streams into process water streams to replace fresh water. These changes can introduce minor water savings and new risks to the process that have to be understood better before implementation. • The mill has progressed far with the design and costing of a proposed effluent treatment plant (ERPl). The integration of this treatment plant into the water network was investigated using the pinch technique. The pinch solver suggested a totally different approach to the integration of the ERPI plant compared to design of the mill. The mill's design revolves around the treatment of low chloride streams in the ERPl plant and using of the treated water as make-up to the cooling towers. Sodium was recovered as raw material from the cooling towers' blow-down. Pinch proposed treatment of the high cWoride containing streams and returning the streams to users suitable of using high chloride water. The network proposed by mill's design generates 8.2 MLlday effluent less than the pinch proposal, and recovers sodium as raw material. The proposal presented by pinch is not recommended and points to the difficulty in simulating factors, such as raw material recovery, in a pinch analysis. • Users for the excess storm water were identified using water pinch and will be suitable for implementation. The mill has mwever decided on alternative sinks for the storm water based on considerations such as process inter-dependency, risks associated with contamination and general management philosophy for the different systems in the mill. These considerations could have been included into the pinch solver, but were not because it was of interest what the second best option would be. • The pinch investigation proved useful to confirm certain understandings of the mill. The investigation confirmed the difficulty of improving the water systems of the mill due to the fact that Ngodwana is already a highly closed and integrated mill. Numerous smaller process changes have been identified by the pinch solver and could be investigated further for smaller process improvements. • It i; recommended that pinch technology be applied again when the mill plans to make major process changes or expansions. It is also recommended to use water pinch on a more frequent basis in smaller sections of the mill or for other evaluations in the mill. As a group Sappi could benefit from the use of water pinch, especially in situations where the water network of the mill is not already water efficient. • The recommendations and conclusions in this report have not been subjected to technical and economical feasibility studies. Extensive further studies must be conducted before implementation of any of the results. Further studies must include impacts from process dynamics, long term effects, impacts from other contaminants that have not been simulated, etc. / Thesis (M.Sc.Eng.)-University of KwaZulu-Natal, Durban, 2009.

The purpose of this study is to develop a deeper understanding of the formation and performance of the international water management institutions operating in the Orange-Senqu basin shared between Lesotho, South Africa, Botswana, and Namibia. The research examines the influence of interstate interaction on adaptive capacity and the allocation of water and related benefits within the Orange-Senqu basin and provides explanations for how and why particular cooperative arrangements emerged and produce differential effects. By applying a structure-agent approach to regime analysis, this study draws attention to four key factors underpinning the formation and performance of the Orange-Senqu water governance regime: power asymmetry, problem structure (i.e., the combination of interest asymmetry and uncertainty), expert networks, and political context. The study demonstrates that each of these four factors provides important and complementary insight into the process of interaction of and the positive and negative effects produced by international water management institutions in the basin and opportunities for generating change. Among these factors, the study argues, power asymmetry and problem structure are critical for understanding transboundary water governance dynamics and identifying strategies for challenging the status quo.

A dissertation submitted to the Faculty of Engineering and the Built Environment, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the degree of Master of Science in Engineering, 2016 / The water-energy nexus considers the relationship between water and energy resources. Increases in environmental degradation and social pressures in recent years have necessitated the development of manufacturing processes that are conservative with respect to both these resources, while maintaining financial viability. This can be achieved by process integration (PI); a holistic approach to design which emphasises the unity of processes. Within the realm of PI, water network synthesis (WNS) explores avenues for reuse, recycle and regeneration of effluent in order to minimise freshwater consumption and wastewater production. When regeneration is required, membrane-based treatment processes may be employed. These processes are energy intensive and result in a trade-off between water and energy minimisation, thus creating an avenue for optimisation. Previous work in WNS employed a black box approach to represent regenerators in water minimisation problems. However, this misrepresents the cost of regeneration and underestimates the energy requirements of a system. The aim of the research presented in this dissertation is to develop an integrated water regeneration network synthesis model to simultaneously minimise water and energy in a water network. A novel MINLP model for the design of an electrodialysis (ED) unit that is capable of treating a binary mixture of simple salts was developed from first principles. This ED model was embedded into a water network superstructure optimisation model, where the objective was to minimise freshwater and energy consumption, wastewater productions, and associated costs. The model was applied to a pulp and paper case study, considering several scenarios. Global optimisation of the integrated water network and ED design model, with variable contaminant removal ratios, was found to yield the best results. A total of 38% savings in freshwater, 68% reduction in wastewater production and 55% overall cost reduction were observed when compared with the original design. This model also led to a 80% reduction in regeneration (energy) cost. / GS2016

A research report submitted to the Faculty of Science school of Geosciences in partial fulfillment of the requirements for the degree of Masters of Science in Hydrogeology. Johannesburg, June 2017. / The Masama Sandstone Aquifer is located in a semi-arid region of south-eastern Botswana where there are no perennial rivers. Groundwater is the main source of water supply for the communities. Historically many water drilling programs have been carried out in this area and the hydrogeological system has been conceptualized. An integrated approach coupling environmental isotopes, radioisotopes and multivariate statistical analysis of the hydrochemical variables was employed to study the origin, age, recharge conditions, rock-water interaction and the hydrological link between the aquifer and geological structures. The major ions in this area are Na+, Ca2+, Mg2+ and HCO-3. Groundwater in the Masama area fall in the transition from a Na-HCO-3 –type through Ca-Na-HCO-3 to Ca-Mg-HCO-3 -type waters from the western to the eastern part of the area. The water types are as a result of cation exchange, carbonate dissolution and rock-weathering processes. The δ18O and δ2H values vary spatially depending on the source of moisture, rainfall season, geology, topography and groundwater circulation depth. Deep circulating groundwaters are isotopically depleted whilst shallow circulating groundwaters are isotopically enriched with respect to winter rain. Low tritium values < 0.8TU and 14C values < 80pmc testifies for recharge. Recent rainfall amount in the area is not sufficient enough to make a profound replenishment in the aquifer. Tritium, 14C and Chloride Mass Balance helped in identifying recharge location and hydrologic connections between structures and the sandstone aquifer elucidating that recharge zones are in the NE and NW of the study area. High recharge rates occur in the north-eastern part and the Makhujwane fault act as a conduit for groundwater recharge. This study provides a better understanding of the aquifer and the information contained herein can be incorporated into future works for sustainable use of the groundwater resource. / XL2017