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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

The implementation of the water release module of the WAS program at the Vaalharts Water Users' Association

Jansen van Vuuren, Arno January 2008 (has links)
Thesis (M. Tech) - Central University of Technology, Free State, 2008 / Food and water are two basic human needs. International projections indicate that water shortages will be prevalent among poorer countries where resources are limited and population growth is rapid, such as the Middle East, parts of Asia and Africa. Provisional estimates are that South Africa will run out of surplus usable water by 2025, or soon thereafter. Urban and peri-urban areas will therefore require new infrastructure and inter-basin transfers to provide safe water and adequate sanitation. Due to the high cost of these developments, such water is seen as being used for industrial and public needs only and not for irrigation. Currently, the agricultural water users consume the majority of the water used by humans. Taking cognisance of the before mentioned it is a reality that in the future the irrigation sector will have to sacrifice some of its water for public and industrial usage. This suggests growing conflict between the different water users and the agricultural water users. An attempt by the Department of Water Affairs and Forestry (DWAF) to address this conflict has been the implementation of pilot studies to determine the steps Water User Associations (WUAs) could take to ensure more effective water use in the future by the agricultural sector. These steps include an increase in irrigation efficiency according to the benchmarks of crop irrigation requirements and more efficient dam and canal management. The Water Administration System (WAS) has been developed to fulfill this exact requirement as it ensures optimal delivery of irrigation water on demand. The program is designed as a management tool for irrigation schemes, WUAs and water management offices to manage their accounts, and also to manage water supply to clients more efficiently through canal networks, pipelines and rivers. The WAS program consists of four modules that are integrated into a single program. Three modules of the WAS program have already been implemented at the Vaalharts irrigation scheme. This scheme has been transformed from a government controlled scheme to a privately owned scheme, and is now known as the Vaalharts Water User’s Association (VHWUA). The main purpose of this study was to implement the fourth module of the WAS program at the VHWUA as only full functionality of the complete program will ensure effective water use at the scheme. The fourth module calculates the volume of water to be released for all the canals (main canal and all its branches), allowing for lag times, water losses and accruals in order to minimise waste and thus save water. The methodology followed in this study was to first of all develop an understanding of the distribution cycle and the current calculation procedure of the VHWUA. The fourth module was then applied on a typical feeder canal and used to calculate the release volumes in order to compare these results with the current values. The next step was then to verify all data abstracted from the database used by the WAS program to calculate the release volumes. The database consists of information like cross-sectional properties, positioning of the sluices, canal slope, as well as canal capacities. The verification of data was done by field work, by studying existing engineering design drawings, through meetings and consultations with all parties involved in the VHWUA as well as by mathematical calculations. Cross-checking and verification, if necessary, of all above mentioned data were done. After the verification process, the database was updated and another cycle of calculations were run to do the final calibrations. Accurate calibrations were done to the seepage and the lag time coefficient. Some final adjustments were also made to the canal geometry in the database. This was an important part of the study as only a trusted and verified database will deliver correct results, irrespective of the software program used. After calibration of the database, the fourth module was again applied, but this time water losses were included in the calculations and the results revealed trustworthy and accurate real-time release volumes. The study therefore succeeded in the implementation of the fourth module on a typical feeder canal at the VHWUA. The study was concluded by the compilation of a checklist, which the VHWUA can use to implement the module on the whole scheme. This would enable the VHWUA to implement and apply the complete WAS program, which offers all the benefits and answers in every need of any water management office. Sustainable water resource utilisation can only be achieved through proper management. Applying this most effective management program will ensure a cost effective and optimised process at the VHWUA.
12

An investigation of community learning through participation in integrated water resource management practices

Phiri, Charles M January 2012 (has links)
South Africa is a semi arid country in which the average rainfall of 450mm/year is well below the world average of about 860mm/year. As a result, South Africa’s water resources are scarce in global terms and limited in extent. Current predictions are that demand will outstrip water availability in the next 15 years. A coordinated approach to improve both water quality and quantity is needed and in order to achieve that, it is crucial to strengthen capacities of local community involvement in identifying the problems that affect them and strategies to solve them. This research was undertaken to develop a deeper understanding of community learning processes in integrated water resources management (IWRM) practices. The study drew on situated and social learning theory which explains that knowledge and skills are learned and embedded in the contexts in which knowledge is obtained and applied in everyday situations. Multiple data collection techniques were used within a case study design and included document analysis, interviews, focus group discussions and field observations. Data analysis was done in three phases and involved uncovering patterns and trends in the data sets. In this context I discovered, through careful observation and interviews with members of the different communities of practice, that people are learning through social learning interactions with other community members as they engage in their daily water management and food production practices. Learning interactions take place through both informal and formal processes such as meetings, training workshops, conversations and interactions with outsiders. I also discovered that people learn from ‘external groups’ or training programmes which bring new knowledge and expertise, but this needs to be contextualised in the local communities of practice. The research has also shown that there are a number of challenges that appear to exist in these learning contexts. For instance it was found that participation and social learning processes and interactions are influenced by a range of causal mechanisms that are contextual. These insights into how communities learn, as well as the tensions and difficulties that are experienced in the learning processes are important for furthering learning and participation in community-based IWRM practices, projects and programmes.
13

Rivers as borders, dividing or uniting? : the effect of topography and implications for catchment management in South Africa

Smedley, David Alan January 2012 (has links)
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.

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