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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.
381

Responding to a city's water prices : the case of Tshwane

King, Nicola Ann 27 October 2006 (has links)
Please read the abstract in the 00front part of this document / Dissertation (MCom (Agricultural Economics))--University of Pretoria, 2006. / Agricultural Economics, Extension and Rural Development / unrestricted
382

A planning strategy for water supply within vacation areas of the Gulf Islands : Hornby - a case study

Lubkowski, Albert Otto January 1972 (has links)
This thesis was prepared in response to growing public concern over potential problems of groundwater development within newly subdivided areas of the Gulf Islands. These "problems" stem from provincial regulations which permit large scale subdivision of residential lots over 18,000 square feet without reference to water supply. The Study strives to resolve conflicting opinions presented on behalf of the public, planners and other government officials as to what constitutes an appropriate policy for water servicing within vacation areas of the Gulf Islands. A chief problem in this regard is the lack of official posture defining objectives for vacation lot subdivision. While the focus of this investigation is primarily groundwater supply and the question of standards for vacation areas, the writer was necessarily drawn into several related areas of concern; namely, those environmental problems arising from water use and waste water disposal; development plans of lot owners and associated preferences for servicing; and inevitably, the legal-bureaucratic hoops and powers which comprise the subdivision process. Study findings support the thesis hypothesis that "organized systems of water supply are an appropriate requirement for those lands which are being subdivided for vacation use purposes". The sub-hypothesis that "the servicing requirements for such systems should be sufficiently flexible to permit if not encourage rudimentary systems if water supply was vindicated also--but only on the condition that groundwater supplies are relied upon and on-site disposal systems are in use. The underlying concern with "rudimentary" servicing is based upon the realization that such servicing policies can be most instrumental in restraining year around development and the urban transformations usually implied. The thesis is based on the belief that the vacation use function and the life style and environment implied can only be preserved if distinctive servicing policies are introduced by regional districts concerned. Their responsible involvement would enable people to continue "to go to a place which is different from the place they left". / Applied Science, Faculty of / Community and Regional Planning (SCARP), School of / Graduate
383

Thirsty downstream : the provision of clean water in Jakarta, Indonesia

Argo, Teti Armiati 05 1900 (has links)
The challenge of water provision in third world cities is to maintain the supply in the context of inadequate and inefficient piped water infrastructure and diminishing raw resources. In order to examine the role of governance in this, I utilize a range of theoretical positions: the welfare orientation, rational choice paradigm, common goods theory and regime theory, and present them as ways to explore the subjective dimension of water provision. Using the city of Jakarta, Indonesia as a case study, this dissertation explores the issues using different perspectives on a single principal focus, the roles of the government and its relations to non-governmental actors. This research used data from secondary materials such as management reports, policy and academic reports, and scientific studies. The major source of primary data were interviews conducted with about 40 key actors. Qualitative analysis used a system of information coding and triangulation. The conclusion reached is that the approach to managing clean water provision needs to be redefined in relation to the water management regimes found in situated research. In Jakarta, one may define three regimes: piped water, surface and shallow groundwater, and deep groundwater. Accessing water from greater urban watershed, treatment plants and a "manufacturing process" results in the delivery of a product. Such a system reduces the possibility of the tragedy of the commons, that is, the over-extraction of groundwater by individuals. But a more inclusive and enforced regulatory system must be established for groundwater, as it remains a needed source of supply. Local and low-technology solutions, international agency assistance, the policies of privatization and decentralization, and better land use planning, all hold out the promise of movement towards a solution. But, as the case study demonstrates, success has so far been mixed. Many options do not address water scarcity at the city level and problems of inequitable service. It is only the prospect government reform towards a better allocation of roles, new management ideas and greater co-operation within and among the water regimes that will lead to better provision of clean water. / Applied Science, Faculty of / Community and Regional Planning (SCARP), School of / Graduate
384

Water services delivery in Mukondeni Village in Limpopo Province, South Africa

Netshipale, Lidzani Lucas January 2016 (has links)
Thesis (M. Dev.) -- University of Limpopo, 2016 / The provision of basic water services delivery to all South African citizens is one of the biggest challenges of many local municipalities. The objective of this study was to explore water services delivery in the communities of Mukondeni village in Limpopo Province. The Department of Water Affairs and Forestry (DWAF) has the responsibility to ensure that all South Africans have access to basic water supply and emphasizes on speedy delivery of water and sanitation services. The Department of Water Affairs (DWA) is mandated with managing and protecting the country‘s water resources, with the National Regulator responsible for systems of accountability. The study evaluated the respondents of the communities, authorities responsible in water services delivery and the nature of the resources in water supply. The outcome of the study shows that, the communities and water services department (workers) were dissatisfied with the current water services delivery. Direct involvement, coordination and co-operation by the government, as well as developing a culture of empowering the local communities should bring better water services delivery to the village and to Mutale Local Municipality in general. The study recommends that one main pipeline from the plant to Mukondeni village should be installed and awareness campaigns for efficient and effective use of water should be launched. This should help ease and improve the present precarious situation.
385

Investigation of the Ramotswa Transboundary Aquifer area, groundwater flow and pollution

Modisha, Reshoketswe Caroline Oudi January 2017 (has links)
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
386

Numerical modelling of groundwater flow at Mogalakwane Subcatchment, Limpopo Province : implication for sustainability of groundwater supply

Marweshi, Manare Judith January 2022 (has links)
Thesis (M.Sc.(Geology)) -- University of Limpopo, 2022 / The Limpopo Province is largely underlain by crystalline basement rocks, which are characterised by low porosity and permeability. The climate in this province is arid to semi-arid, with scarce surface water for domestic and industrial use. As a result, groundwater is the prime source of fresh water supply for various uses. The complex geology, the impacts of climate change and man-made interactions with groundwater and surface water are the main threat to the availability of a sustainable source of fresh water in the province. In addition, despite substantial research efforts conducted by academic institutions and government organisations, there is still a gap in understanding quantitatively the dynamics of the hydrological systems in large parts of the Limpopo Province. The present study is therefore focused on the investigation of hydrological stresses that are applied to groundwater and surface water in one of the catchments situated in the Limpopo Province. In this study, a three-dimensional steady-state numerical model of groundwater flow was carried out at Mogalakwena Subcatchment, which is situated in the western sector of the Limpopo Province. The area is situated approximately 40 km northwest of Mokopane and 50 km west of Polokwane town. The research aims to understand the dynamics of the exchange between surface water and groundwater, and to assess the influences of these processes on the sustainability of water supply in the area. Hydrologically, the area falls within the boundaries of the Mogalakwena River Catchment, which forms part of the Limpopo River Basin. Previous studies suggest that there is a continuous decline in groundwater levels in the study area due to extensive use of groundwater for mining, irrigation, and domestic purposes. Furthermore, continued climate changes have altered the rainfall events during the last couple of decades, which consequently had an impact on groundwater recharge, quality, and availability. In addition, the complex geology of the area has an impact on the aquifers’ productivity resulting in variability in borehole yields throughout the study area. To achieve the aims of the research project, a three-dimensional steady-state numerical model of groundwater flow was implemented using MODFLOW NWT and ModelMuse v graphical user interface. The model domain covers an area of 5896 sq. km and was discretised with a grid cell size of 200 m by 200 m. The MODFLOW Packages used include DIS, UPW, RCH, EVT, WEL, GHB, RIV and UZF as well as the ZONEBUDGET. The conceptual model of groundwater flow consists of two layers, and it was developed based on drillhole logs, hydrochemical data, environmental isotopes, geological, digital terrain models, and other spatial data relevant for the conceptualisation of boundary conditions and hydrological stresses. The results of the steady-state simulation of groundwater flow show that recharge contributes 99.6% of inflow, followed by river leakage (0.36%) and GHB (0.08%). Among the outflow components, surface runoff takes the lion’s share (83.3%), followed by evapotranspiration (16.6%) and river leakage 0.02%. The zone budget was implemented to evaluate the interaction between surface water and groundwater by quantifying the amount of water that flows from one zone to the other. This was achieved by assigning zone numbers to the objects that represent boundary conditions (e.g., aquifer, river and dam). Zone 1, 2 and 3 were assigned to the aquifer, river and dam, respectively. The results indicate that the rivers gain more water than they supply to the aquifer. Similarly, the Glen Alpine Dam gain more water from the aquifer than it supplies to the aquifer. This implies that the interaction between surface water bodies such as rivers and dams have a significant impact on the aquifer, which consequently partly contributed to the shortage of water in the area. A predictive analysis of the aquifer’s response to an increase in abstraction rate, evapotranspiration rate and a decrease in recharge was carried out to investigate the future fate of water availability in the study area. The results suggest that as recharge decreases, the river inflow slightly increases to compensate for the declining water level due to the river stage exceeding the piezometric surface. In addition, the decrease in recharge rate is accompanied by a slight decrease in both surface runoff and evapotranspiration rate. Thus, a decline in recharge causes a significant drop in piezometric surface relative to the evapotranspiration extinction depth, which ultimately decreases the rate of evapotranspiration. Similarly, a decrease in recharge rate lowers the depth of the water level below the river stage, which consequently triggers water vi exchange from Mogalakwena River to the aquifer. In general, the water balance shows that as recharge decreases by 20% or more, the outflows exceed the inflows resulting in a continuous drop in water level, which may ultimately risk the availability of groundwater in the area. / Council for Geoscience (CGs)
387

Sharing water : a human ecological analysis of the causes of conflict and cooperation between nations over freshwater resources /

Green, Brian E. January 2002 (has links)
No description available.
388

Optimizing Growth Options for the Wewahootee Pump and Transport System

Lung, Joseph O. 01 April 1982 (has links) (PDF)
Techniques for performance optimization and energy reduction were reviewed for application to water supply plants. Simple techniques were developed which permit intelligent management decisions for plant operation growth. The techniques were applied to the Wewahootee Water Supply Plant, Cocoa, Florida. Optimum performance for the existing plant was determined together with a growth plan for reducing energy consumption and increasing the maximum flow capacity to meet demand through the year 2000. The following recommendations were made: 1. Plant operators should incorporate the optimized pump operation schedule presented herein. 2. Four existing pumps should be modified for dual speed operation, and a large capacity dual speed pump should be added. 3. One 10,400 foot section should be added to the 42-inch pipe by 1985 and a second section by 1990. 4. An economic analysis should be performed to determine if it is advantageous to accelerate installation of the 42-inch pipe. 5. The use of stored water should be considered to smooth the flow demands placed on the pumps.
389

Investigation of a new water supply for the Virginia Polytechnic Intitute and the town of Blacksburg

Hurst, W. D. January 1931 (has links)
M.S.
390

A Procedure for the Preliminary Assessment of Water Supply Availability

Wallace, Troy Brandon 29 March 2001 (has links)
Of the factors that determine development potential in a given geographic area, the availability of water for residential, commercial, and industrial purposes is a primary indication of prospective growth. Governmental bodies at the regional, state and federal levels often need to identify water supply availability in order to identify growth potential. To address this need, a procedure for the preliminary assessment of water supply availability has been developed that can potentially be applied to any geographic area in the United States. The procedure uses the USGS demand cataloging unit as the basic planning area, with supply estimates from streamflow parameters at USGS gage locations and demand estimates from USGS demand reports. By comparing known supply and demand estimates in a base year, an overview of water supply availability in the region can be determined. With supply and demand data in a base year, projections of future water supply availability can then be made. Detailed projection of future water demand must account for changes in the amount of water use activities and the rates of water use within those activities, but a simplified procedure is applied here. Total offstream water use is averaged over the population in the base year to determine per-capita offstream use, which is assumed to remain constant in the future in this preliminary assessment procedure. Population is then projected and demand is forecast as a function of the projected population. The supply quantity is projected assuming each flow parameter derived from the historical record will remain constant in the future year. By comparing projected supply and demand estimates, water supply availability in future years can be anticipated in the planning area. / Master of Science

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