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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.
1051

Water quality information system for integrated water resource management

Tukker, Mary Jean 12 1900 (has links)
Thesis (MEng)--University of Stellenbosch, 2000. / ENGLISH ABSTRACT: The processes of monitoring, modelling and managing the water quality of a catchmerit system including all its unique complexities and interrelationships requires an innovative tool or set of tools to help water managers with their decision making. Numerous methods and tools have been developed to analyse and model the real world. However, many of these tools require a fair degree of technical expertise and training to operate correctly and their output may have to be translated or converted to meaningful information for decision-making using a further set of analytical and graphical display tools. A more appropriate technique for management would be to combine all these functions into a single system. The objective of this research was to develop one such tool, an integrated water quality information system (WQIS). A review of the literature revealed that there has been extensive research and development of tools for the management of individual aspects of water resource distribution, augmentation and quality. However, these tools have rarely been integrated into a comprehensive information system offering decision support to a wide variety of river users and managers. Many of the literature sources also noted that a process of interactive development and integration (i.e. including the intended users in the decision of which components to include, the interface design and the graphical display and output) was vital to ensuring the information system becomes an integral part of the users routine work and decision-making. The WQIS was developed using the recommendations from numerous knowledgeable persons in response to questionnaires, interviews and a prototype demonstration. It includes the results of hydrodynamic river and reservoir simulations and the ability to perform operational river scenario testing. However, the development process is continual and always evolving based on the current or local requirements of water managers. These further developments and research needs are discussed in more detail in the conclusion. / AFRIKAANSE OPSOMMING: Die proses om die waterkwaliteit van 'n opvanggebied, met al die unieke kompleksiteite en onderlinge verhoudings van so 'n stelsel te monitor, modelleer en bestuur, vereis 'n innoverende instrument om waterbestuurders te ondersteun in hul besluitnemings. Talle instrumente en metodes vir die ontleding en modellering van die werklikheid is reeds ontwikkel. Die gebruik van hierdie instrumente vereis gewoonlik 'n redelike mate van tegniese kundigheid en opleiding. Dit mag verder nodig wees om die uitvoer van sulke instrumente te vertaal en/of om te skakel na betekenisvolle inligting vir besluitneming deur die gebruik van bykomende analitiese en grafiese vertoon instrumente. 'n Meer toepaslike bestuurstegniek sou wees om al die funksies in 'n enkele stelsel te kombineer. Die doel van hierdie navorsing was om een so 'n instrument, naamlik 'n geïntegreerde waterkwaliteit inligtingstelsel (WQIS), te ontwikkel. 'n Hersiening van bestaande literatuur het getoon dat daar omvattende navorsing en ontwikkeling van instrumente gedoen is vir die bestuur van individuele aspekte van waterbronverspreiding, waterbronaanvulling en waterkwaliteit. Integrasie van hierdie instrumente, in 'n uitgebreide stelsel wat besluitnemingsondersteuning aan 'n verskeidenheid riviergebruikers en bestuurders bied, kom egter selde voor. Verskeie literatuurbronne het ook aangedui dat 'n proses van interaktiewe ontwikkeling en integrasie (m.a.w. in agname van die voorgenome gebruikers se behoeftes in die kense van komponente, die gebruiker raakvlak ontwerp en grafiese vertoon instrumente en uitvoer) noodsaaklik is om te verseker dat die inigtingstelsel 'n integrale deel word van die gebruiker se daaglikse roetine en besluitnemingsproses. Die WQIS is ontwikkel deur gebruikmaking van die insette en aanbevelings van verskeie kenners in reaksie op vraelyste, onderhoude en 'n demonstrasie van 'n prototype. Dit sluit in die resultate van hidro-dinamiese rivier en dam simulasies en die vermoë om operasionele rivier scenario ontledings uit te voer. Die ontwikkeling is egter 'n deurlopende proses, gebaseer op huidige of plaaslike behoeftes van waterbestuurders. Hierdie verdere ontwikkelings- en navorsingsbehoeftes word meer breedvoerig in die gevolgtrekkings bespreek.
1052

Coastal water quality.

Mardon, David W. January 2003 (has links)
This research focuses on the pathogenic pollution of coastal recreational waters. Pollution of this resource can have serious social and economic implications. The health of the public could be compromised and there may be associated adverse impacts on the tourism industry. A section of coastline along the Durban Bight and including some of the nation's premier bathing beaches, was used for a case study. The water quality condition of the beaches was evaluated against both local and international marine recreational water quality standards. Most of Durban's bathing beaches were found to have good water quality. However beaches situated close to stormwater drains regularly experience poor water quality conditions. The relationships between beach water quality, the pollution sources and environmental factors such as rainfall were quantified. A weak correlation was found between rainfall and beach pathogenic pollution levels. No correlation was found between successive fortnightly beach samples indicating that the time scales of coastal dispersion processes are significantly shorter than the beach monitoring period. The research also indicates a need to update the SA marine water quality standards. The exclusive use of Escherichia coli (E.coli) as the indicator of faecal pollution is inconsistent with international trends towards the use of Enterococcus, which is a more robust pathogen indicator for marine environments. The main aim of the research was to develop a model to predict the water quality conditions of beaches. The Coastal Water Quality Model (CWQM) is intended to serve two functions: firstly to provide daily estimates of pathogenic pollution levels for beach management (e.g. closure under poor water quality conditions), and secondly to provide decision-makers with a tool for predicting the effects of changes on future water quality conditions. The CWQM was formulated as a stochastic state-space lumped advection diffusion model. A Kalman Filter was used for state estimation. Parameter estimation using the Extended Kalman filter was investigated but found to be unsatisfactory due to large input uncertainties and sparse measurements. An alternative statistical fitting procedure was therefore used for parameter estimation. The model was shown to produce accurate predictions of pathogenic pollution for the case study site. To further demonstrate it's utility. it was used to evaluate options for improving the poor water quality at Battery Beach. The results show that a constructed wetland could be effective in this case. / Thesis (M.Sc.)-University of Natal, Natal, 2003.
1053

Spatial and Temporal Influences of Water Quality on Zooplankton in Lake Texoma

Franks, Jessica L. 05 1900 (has links)
Seventy-one aquatic species including the copepodids and nauplii were identified from Lake Texoma from August 1996 to September 1997. Zooplankton community structure, abundance and spatial and temporal distributions were compared among five lake zones delineated a priori based on chloride concentration. The zones, in order of decreasing chloride concentration, are the Red River zone (RRZ), Red river Transition zone (RRTZ), Main Lake zone (MLZ), Washita River Transition zone (WRTZ) and Washita River zone (WRZ). Bray Curtis Similarity Index showed community structure was most similar in the two Red River arm zones, the two Washita River arm zones and the MLZ. Zooplankton abundance was greatest in the Red River arm (312 org/L), intermediate in the Washita River arm (217 org/L) and least in the Main Lake body (103 org/L). A significant increase in the abundance of a deformed rotifer, Keratella cochlearis, was observed mainly in the Red River arm during a second study from March 1999 to June 1999. Seasonal dynamics, rather than spatial dynamics, were more important in structuring the zooplankton community, especially in the two river arms. Spatial variance was solely attributed to station and zone effects independent of time for a few crustacean species and many of the water quality parameters supporting the presence of longitudinal gradients of differing water quality. Three independent models (Red River arm, Washita River arm, Main Lake body) rather than a single model for the entire reservoir, best describe patterns in the zooplankton community and its relationship to seasonal, physical and chemical factors. Statistical power, sample size and taxonomic resolution were examined. When monitoring seasonal and annuals trends in abundance, the greatest statistical power was achieved by analyzing count data at taxonomic levels above genus. Taxonomic sufficiency was assessed to determine if costs could be reduced for zooplankton identifications. For water quality monitoring purposes only, it is recommended that genus identifications are sufficient if supplemented with quarterly species identifications.
1054

Projeto e avaliação de desempenho de redes de monitoramento de qualidade da água utilizando o conceito de entropia.

Soares, Paulo Fernando 24 July 2001 (has links)
A manutenção da qualidade ambiental está diretamente relacionada ao conhecimento e controle das variáveis que interferem no problema, sejam elas resultantes das ações do homem sobre o ambiente ou de suas transformações naturais. Este conhecimento sobre o meio ambiente pode ser obtido através de monitoramento e, no caso dos corpos d’água, a eficácia do monitoramento depende em especial de um projeto e operação adequados do sistema de informações, que é constituído pela aquisição, manipulação, análise e utilização da informação obtida. No que se refere à aquisição da informação, ainda existem grandes lacunas a serem preenchidas na decisão sobre onde, quando e o que monitorar. Neste trabalho são enfocadas as atividades básicas do projeto da rede de monitoramento, ou seja, a localização das estações, a seleção das variáveis, a freqüência e a duração da amostragem, procurando-se buscar um conjunto de diretrizes de aplicação que seja exeqüível e eficaz para o projeto e manutenção de redes de monitoramento, uma vez que não se dispõe atualmente na literatura, de procedimento geral que vise solucionar este problema. A localização das estações de monitoramento na bacia hidrográfica, denominada de macrolocalização, a determinação de freqüências amostrais e a definição das variáveis a serem monitoradas, são tarefas que fazem parte do projeto da rede de monitoramento da qualidade da água. A rede de monitoramento, por sua vez, é parte do sistema de informações sobre qualidade da água, cujo objetivo é a descrição dos fenômenos físicos, químicos e biológicos relacionados à qualidade do corpo d’água. A eficiência da metodologia discutida neste trabalho é demonstrada e discutida através de estudos de casos. Dentre as contribuições deste trabalho podem-se destacar: (i) a ampliação do trabalho de POMEROY e ORLOB, para a localização de estações de monitoramento baseando-se na área e características de drenagem da bacia hidrográfica; (ii) a adaptação do procedimento de otimização no processo de macrolocalização de SHARP; (iii) a dedução da equação da entropia para análise de múltiplas variáveis; (iv) o desenvolvimento de um aplicativo computacional para a análise e avaliação de desempenho de estações de monitoramento baseado no conceito de entropia; e (v) a proposição de uma metodologia geral de dimensionamento e redimensionamento de redes de monitoramento de qualidade da água . Neste trabalho são descritas, discutidas e aplicadas as metodologias disponíveis para a macrolocalização e as recentemente propostas para o redimensionamento de redes de monitoramento, baseadas no conceito de entropia, objetivando a produção de diretrizes de projeto de redes de monitoramento, especialmente para países em desenvolvimento. Assim sendo, neste trabalho não se faz somente uma análise de métodos disponíveis para o projeto de redes de monitoramento mas também é proposta uma metodologia de dimensionamento e redimensionamento de redes de monitoramento para bacias com poucos dados e para bacias com dados de qualidade da água. Desta forma espera-se contribuir com países em processo de início e organização de seus sistemas de informação ambiental, e também para aqueles com suas redes já em operação, facilitando-se a decisão quanto à destinação de recursos para a adequação da realidade financeira aos objetivos de operação e manutenção destes sistemas. / The maintenance of the environmental quality is directly related to the knowledge and control of the variables affected by the problem, either as a result of the human action on the environment, or due to natural transformations. Knowledge on the environment can be obtained through monitoring. The effectiveness of the monitoring especially depends on the project of the information system and its operation. Data acquisition, manipulation, analysis, as well as the use of the generated information, are all activities that must be prepared by the project. As far as the acquisition of information is concerned, there are research gaps about the decision on where, when and what to monitor. This study will focus on the basic activities of the monitoring network project, that is, the location of the stations, the variable selection and the sampling frequency. The objective is to find out a group of application guidelines that has a practical use and is effective both to the project and maintenance of monitoring networks, since a general procedure to solve this problem is not available in the literature. Water quality monitoring networks are part of the water resources information system, with the objective of describing the physical, chemical and biological phenomena related to the quality of the water body. The efficiency of the methodology discussed in this study is demonstrated and discussed through case studies. The most important contributions of this study are: (i) the expansion of the POMEROY and ORLOB studies to locate monitoring stations based on the watershed area and channel network; (ii) the extended use of the optimization procedure proposed by SHARP to improve the macrolocation process; (iii) the deduction of the entropy equation to analyze the multiple variables; (iv) the software to analyze and to propose a new design for monitoring networks, based on the entropy concept; and (v) the proposal of a general methodology to the water quality monitoring network design and redesign. The processes and methodologies proposed in this study were developed to be applied in developing countries. Usually such countries are in the process of initialization and organization of their environmental information systems, and we hope that this study will be able to bring satisfactory benefits, taking into account that optimization is necessary to bring the costs down and to make the monitoring effort sustainable.
1055

Determination of trihalomethanes (THMs) in water by GC/MS.

January 1998 (has links)
by Lai-nor Cheng. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1998. / Includes bibliographical references (leaves 51-55). / Abstract also in Chinese. / TABLE OF CONTENTS --- p.i / ABSTRACT --- p.v / LIST OF FIGURES --- p.vi / LIST OF TABLES --- p.vii / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Water Treatment Process --- p.1 / Chapter 1.2 --- Disinfectants --- p.3 / Chapter 1.3 --- THMs formation --- p.4 / Chapter 1.4 --- Various Guideline Values --- p.6 / Chapter 1.5 --- WHO Guideline Values in 1993 (used in HK) --- p.6 / Chapter 1.6 --- THM-FP --- p.7 / Chapter 1.7 --- Removal Methods --- p.7 / Chapter Chapter 2 --- "Sample Collection, Pretreatment & Storage" --- p.8 / Chapter 2.1 --- Cleaning of Sample Bottles --- p.8 / Chapter 2.2 --- Sample Collection --- p.8 / Chapter 2.3 --- Sample Pretreatment & Storage --- p.8 / Chapter Chapter 3 --- Experimental --- p.9 / Chapter 3.1 --- Analysis Methods --- p.9 / Chapter 3.1.1 --- Sample Preparation Methods --- p.9 / Chapter 3.1.1.1 --- Liquid-liquid Extraction (LLE) --- p.9 / Chapter 3.1.1.2 --- Purge & Trap (P&T) --- p.9 / Chapter 3.1.1.3 --- Static and Dynamic Headspace (HS) --- p.9 / Chapter 3.1.1.4 --- Direct Aqueous Injection --- p.10 / Chapter 3.1.2 --- GC Detectors --- p.10 / Chapter 3.1.3 --- Sensitivity --- p.10 / Chapter 3.2 --- LLE & GC/MS (SIM) --- p.11 / Chapter 3.3 --- Reagents & Apparatus --- p.12 / Chapter 3.3.1 --- Reagents --- p.12 / Chapter 3.3.2 --- Apparatus --- p.12 / Chapter 3.4 --- Procedure --- p.13 / Chapter 3.4.1 --- Pentane Extraction --- p.13 / Chapter 3.4.2 --- Instrument Configuration --- p.14 / Chapter 3.4.3 --- GC Parameters --- p.14 / Chapter 3.4.4 --- MS Parameters --- p.19 / Chapter 3.5 --- Preparation of Standards --- p.19 / Chapter 3.5.1 --- Stock Standard Solution --- p.19 / Chapter 3.5.2 --- Primary Dilution Standard --- p.20 / Chapter 3.5.3 --- Secondary Dilution Standard --- p.20 / Chapter 3.5.4 --- Calibration Standards --- p.20 / Chapter 3.6 --- Validation of the method --- p.21 / Chapter 3.6.1 --- Calibration Graphs --- p.21 / Chapter 3.6.2 --- Recovery & Precision --- p.27 / Chapter 3.6.3 --- Detection Limits --- p.30 / Chapter 3.7 --- Quality Control --- p.30 / Chapter Chapter 4 --- THMs levels and THM-FP of Tapwater --- p.31 / Chapter 4.1 --- Sample Collection Sites in HK --- p.31 / Chapter 4.2 --- Data Acquisition --- p.31 / Chapter 4.3 --- Calculations --- p.31 / Chapter 4.3.1 --- Blank Correction --- p.31 / Chapter 4.3.2 --- Calculation of THMs concentration --- p.31 / Chapter 4.3.3 --- "Mean, Standard Deviation & RSD %" --- p.32 / Chapter 4.4 --- Summary of THMs levels & THM-FP in tapwater of HK --- p.32 / Chapter 4.4.1 --- THMs levels in tapwater of HK --- p.33 / Chapter 4.4.2 --- THM-FP in tapwater of HK --- p.34 / Chapter 4.5 --- THMs levels & THM-FP in the 19 districts of HK --- p.34 / Chapter Chapter 5 --- "THMs levels of Well, Distilled & Mineral water" --- p.42 / Chapter 5.1 --- THMs levels and THM-FP of Well water --- p.42 / Chapter 5.2 --- THMs levels of Distilled water --- p.42 / Chapter 5.2 --- THMs levels of Mineral water --- p.43 / Chapter Chapter 6 --- Removal Methods --- p.44 / Chapter 6.1 --- Heating --- p.44 / Chapter 6.1.1 --- Procedure --- p.44 / Chapter 6.1.2 --- Results --- p.45 / Chapter 6.2 --- Activated Carbon Filter --- p.47 / Chapter 6.2.1 --- Procedure --- p.48 / Chapter 6.2.2 --- Results --- p.48 / Chapter Chapter 7 --- Conclusion --- p.49 / References --- p.51 / Appendix --- p.56 / Chapter A. --- Properties & Toxicity of THMs --- p.57 / Chapter B. --- Collection Date & Time of Tapwater samples & Well water samples --- p.59 / Chapter C. --- THMs levels of Tapwater in the 57 collection sites of HK --- p.62 / Chapter D. --- THM-FP of Tapwater in the 57 collection sites of HK --- p.69 / Chapter E. --- Raw data ofTHMs levels (μg/L) in Tapwater of HK --- p.76 / Chapter F. --- Raw data of THM-FP levels (μg/L) in Tapwater of HK --- p.90 / Chapter G. --- Raw data of THMs concentrations in Well,Distilled & Mineral water --- p.104 / Chapter H. --- Specification of Activated Carbon Filter --- p.106 / Chapter I.(1) --- Mass Spectrum of Chloroform --- p.108 / Chapter (2) --- Mass Spectrum of Chlorodibromomethane --- p.109 / Chapter (3) --- Mass Spectrum of Bromodichloromethane --- p.110 / Chapter (4) --- Mass Spectrum of Bromoform --- p.111
1056

Water Quality Indicators in Watershed Subbasins with Multiple Land Uses

Aull, Malia Elizabeth 03 May 2005 (has links)
The wide use and accessibility of surface waters leads to multiple sources of contamination. The two main forms of pollution are from point and nonpoint sources. Point sources are regulated by the federal government; however, nonpoint sources are more difficult to regulate since there is no defined origin. Due to this problem, surface water monitoring is performed by state agencies which can include the testing of several different water quality indicators chosen by the state. This thesis examines several water quality indicators from two watershed subbasins with different land uses. The types of contamination and sources were evaluated from the data, which was analyzed based on sampling site, season, and two statistical tests. The water quality indicators that were examined in this study included physical, chemical, and microbiological indicators. The two subbasins that were monitored were located in the Wachusett reservoir watershed in central Massachusetts. One subbasin, Malagasco Brook, was located south of the reservoir. Six sampling sites were chosen in proximity to a swampy area, a nursery, and condominium housing complex. The second subbasin, Beaman Pond, was located to the northwestern side of the reservoir and was monitored at three sites. These sites were located in a residential area in addition to a special use two acre farm. Analyses were performed by site and by season to find trends in the data. Statistical correlation and ANOVA analyses were performed in order to better understand the relationships of the water quality indicators. From these analyses, it was determined that organic carbon and human sources of contamination were significant in the Malagasco Brook subbasin. Organics originated in the headwaters and nursery area, and the residential area was a possible source of microorganisms. The Beaman Pond subbasin was found to be affected by both human and animal sources of contamination. Downstream of the farm, animal contamination was found and supported by measurement of microbial source tracking indicators. The other two sites were affected by human sources, a result of septic systems. Strong correlations were found between several water quality parameters, including temperature and dissolved oxygen, turbidity and particle counts, and fecal coliforms and enterococcus. Based on data usefulness and ease of measurement, it is recommended that temperature, DO, conductivity, pH, dissolved organic carbon, turbidity or particle counts, and fecal coliforms be included in a routine watershed monitoring program.
1057

Adaptação do índice de qualidade da água (IQA) para aplicação no monitoramento de cursos hídricos em um empreendimento rodoviário

Santini, Jaerton January 2017 (has links)
O presente trabalho abrange um estudo sobre a utilização de Índices de Qualidade da Água (IQA) para o monitoramento de cursos hídricos durante a fase de construção de um empreendimento rodoviário. Uma vez que obras rodoviárias tem potencial para causar numerosos impactos ambientais, inclusive, em cursos hídricos. Desta forma o monitoramento da qualidade da água é essencial para a manutenção da qualidade da água e minimização dos possíveis impactos. Atualmente existem inúmeras metodologias, que podem ser utilizadas para o monitoramento de cursos hídricos. Entre eles, destaca-se o IQA desenvolvido pela National Sanitation Foundation (NSF, 2010) e o IQA adaptado pela Companhia de Tecnologia de Saneamento Ambiental do Estado de São Paulo (CETESB). Porém, esta metodologia incorpora variáveis consideradas relevantes para a avaliação da qualidade das águas destinadas para abastecimento público. Assim, faz-se necessário calibrar o IQA para que reflita de maneira precisa as possíveis interferências sobre a qualidade da água durante a execução de obras rodoviárias Para isso, foram analisados os dados históricos da qualidade da água dos principais cursos hídricos monitorados durante a fase de implantação do Arco Rodoviário Metropolitano do Rio de Janeiro, considerando parâmetros físico-químicos e microbiológicos para o cálculo do IQA. Através da analise de componentes principais (ACP) foram obtidos coeficientes que possibilitaram a calibração do novo Índice de Qualidade da Água. Com a calibração concluída, procedeu-se para uma nova avaliação no IQA dos cursos hídricos monitorados. Os resultados obtidos permitem inferir que a utilização do IQA calibrado, possui uma melhor representação dos cursos hídricos monitorados, uma vez que, algumas variáveis tiveram seus pesos alterados e outras foram substituídas do IQA. No entanto, os resultados do IQA calibrado foram inferiores aos resultados do IQA NSF, porém, não foram identificadas alterações na qualidade da água entre os pontos de montante e jusante sendo os resultados influenciados pelas atividades na bacia de contribuição. / This work covers a study on the use of the Water Quality Index (WQI) for the monitoring of watercourses during road construction, considering that such activities lead to several environmental impacts, including those on watercourses. In this way, the monitoring of water quality is essential for maintaining water quality and minimizing possible impacts. Numerous methodologies exist today, which can be used to monitor watercourses. These include the WQI, developed by the National Sanitation Foundation (NSF, 2010) and the WQI adapted by the Environmental Sanitation Technology Company of the State of São Paulo (CETESB). However, this methodology incorporates variables considered relevant for the evaluation of the quality of the water intended for public supply. Thus, it is necessary to calibrate the WQI to accurately reflect possible interferences on water quality of the streams during road construction. Historical water quality data of the main watercourses monitored during the construction of the Arco Metropolitano do Rio de Janeiro was analyzed, considering physical-chemical and microbiological parameters for the calculation of the WQI After the analysis of the main components (PCA), coefficients were obtained that enabled the calibration of the new Water Quality Index. With the calibration completed, a new WQI evaluation of the monitored watercourses was carried out. The results show that the use of the calibrated IQA have a better representation of the monitored watercourses, since some variables had their factors changed and others were replaced by the WQI. The results of the calibrated WQI showed lower values than the NSF WQI results. However, no changes were identified in the water quality between the upstream and downstream points because the results are influenced by the activities in the contribution basin.
1058

Hydrodynamic and Water Quality Modeling of the Tigris River System in Iraq Using CE-QUAL-W2

Al Murib, Muhanned 21 March 2018 (has links)
The Tigris River is one of two primary rivers in Iraq and is, along with the Euphrates, the main source for drinking and irrigation water in the country. The Tigris River originates in the Taurus Mountains in Turkey, and is 1850 km long. The majority of the river lies within Iraq. The river passes through, and is the primary drinking water source for major cities such as Mosul, Baeji, Samarra, Baghdad (the capital), and Kut. The Tigris River joins the Euphrates River in Qurna city within Basra province to form the Shatt Al-Arab River which eventually discharges into the Persian Gulf. As a result of fluctuations in flow rate along the Tigris River that cause both potential flooding and drought, Mosul Dam was built on the mainstem of the Tigris River upstream of the city of Mosul and was operated starting in July 1986 to control the river flow and to generate hydroelectricity. Some canals were also constructed to divert excess fresh water from the mainstem of the river at Samarra Barrage located 125 km north (upstream) of Baghdad to Tharthar Lake, an artificial lake located 100 km northwest Baghdad city. The Tigris-Tharthar canal, 75 km long, was constructed in 1956 to divert excess water from Samarra Barrage to Tharthar Lake and to prevent potential flooding in Baghdad. During dry seasons, high total dissolved solids (TDS) water is diverted from Tharthar Lake into the mainstem of the Tigris River through the 65 km long Tharthar-Tigris canal, which is located 25 km upstream Baghdad. Due to rapid population growth and increasing industrial activates, the Tigris River is also facing many water quality challenges from inflows of contaminated wastewater from treatment plant stations. A water quality model that simulates the Tigris River system is therefore needed to study the effects of these discharges and how water quality of the Tigris River could be managed. To address this issue, CE-QUAL-W2 was used to develop a 2-D (longitudinal and vertical) hydrodynamic and water quality model of the mainstem Tigris River from Mosul Dam (Rkm 0) to Kut Barrage (Rkm 880). In addition, Tharthar Lake and its canals were modeled. A full suite of hydrodynamic and water quality variables were simulated for the year 2009, including flowrates, water level, and water temperature. Additionally, water quality constituents such as total dissolved solids (TDS), phosphate (PO4), ammonium (NH4), nitrate (NO3), biochemical oxygen demand (BOD), chlorophyll-a (Chl-a), and dissolved oxygen (DO) were also simulated. Bathymetry of the Tigris River and field data such as flowrate, water level, TDS, NO3 were obtained from the Ministry of Water Resources in Iraq, while surface water temperatures of the Tigris River were estimated remotely using Landsat satellites. These satellites provided a continuous observation record of remote sites. Other water quality field data, such as PO4, NH4, BOD, and DO, were estimated from literature values. Meteorological data, including, wind speed, wind direction, air and dew point temperatures, cloud cover, and solar radiation were obtained from the Iraqi Ministry of Transportation, the General Organization for Meteorology and Seismic Monitoring. Model predictions of flow and water level were compared to field data at three stations along the mainstem of the Tigris River, including Baeji, downstream of Samarra Barrage, and Baghdad. The absolute mean error in the flow varied from 12.6 to 3.4 m3/s and the water level absolute mean error varied from 0.036 to 0.018 m. The percentage error of the overall flowrate at Baeji, downstream Samarra Barrage and Baghdad was 1.9%, 0.8%, and 0.8% respectively. Injecting a conservative tracer at Mosul Dam showed that a parcel of water reaches to Baeji, Samarra Barrage, Baghdad, and Kut Barrage after approximately 3 days, 5 days, 10 days, and 19 days, respectively. Water temperature field data in Iraq are limited and there was no archive of existing field data. Therefore, I obtained estimates of surface water temperature on the Tigris River using the thermal band of the Landsat satellite, one of a series of satellites launched by the National Aeronautics and Space Administration (NASA). The calibration between satellite data and water temperature was validated using sparse field data from 2004, and the calibration then applied to 82 Landsat images from the year 2009. Landsat estimates showed a bias of -2°C compared to model results in winter months, possibly due to uncertainty in Landsat estimations. The absolute mean errors of the CE-QUAL-W2 model predictions of water temperature compared to Landsat estimated temperatures were 0.9 and 1.0°C at Baeji and Baghdad respectively. Temperature calibration in the Tigris River system was highly sensitive to meteorological input data. Landsat Images were also used to estimate longitudinal variation in surface water temperature of Tharthar Lake. It was found that surface water temperature in Tharthar Lake varied longitudinally along the North-South axis with warmer temperatures in the lower part compared with the upper part of the lake. Total dissolved solids concentrations in the Tigris River significantly increased from Mosul Dam to Kut Barrage with peak concentrations of 900 mg/l and 1050 mg/l at Baghdad and Kut, respectively, due to high TDS water diverted from Tharthar Lake, irrigation return flow, urban runoff, and uncontrolled discharge of wastewater effluents. NO3 concentrations did not significantly increase between Samarra Barrage and Baghdad city. BOD concentrations within Baghdad were extremely high due to direct discharge of industrial wastewater into the mainstem of the Tigris River from outlets located within the city. Management scenarios were simulated with the model of the Tigris River system and were compared with the base model. The main scenarios implemented on the Tigris River system were altering upstream hydrology, increasing air temperature due to the effect of climate change, disconnecting Tharthar Lake from the Tigris River system, and simulating long-term effects on Tharthar Lake. Increasing upstream inflows caused a decrease in TDS concentrations from 495 mg/l to 470 mg/l over all the mainstem of the river. In addition, CBOD concentrations decreased somewhat from 5.9 mg/l to 5.74 mg/l. On the other hand, decreasing upstream flows caused a significant increase in average TDS concentrations over the entire Tigris mainstem from 495 mg/l to 527 mg/l. Also, an increase in CBOD concentrations from 5.9 mg/l to 6.2 mg/l was predicted over all the mainstem of the river. Implementing the climate change scenario on the base model of the Tigris River system showed a 5% increase in annually averaged water temperature from 20.7°C to 21.68°C over the mainstem river. Climate change scenarios produced no significant impacts on TDS and CBOD concentrations in the mainstem, while DO concentrations decreased from 8.15 mg/l to 7.98 mg/l with a slight increase in Chl-a concentration from 1.97 µg/l to 2 µg/l in the mainstem. Disconnecting Tharthar Lake from the system showed a remarkable 25% decrease in TDS concentrations, with an average concentration changed from 495 mg/l to 397 mg/l in the mainstem due to an extra 36% increase in flow discharged downstream of Samarra Barrage. Also, Chl-a concentration significantly decreased by 40% with an average concentration changed from 2 µg/l to 1.2 µg/l. Additionally, a 6-year model simulation of the Tigris River system was performed to evaluate the long-term effects on Tharthar Lake. No significant impact was observed in the average temperature of the lake. TDS concentrations in the lake decreased from 1239 mg/l to 1041 mg/l. PO4, NH4 and NO3 concentrations decreased by 2%, 66% and 26%, respectively. Chl-a concentration in Tharthar Lake decreased from 2.0 µg/l to 1.61 µg/l. After decreasing BOD concentrations of the Tigris River by 50%, BOD concentrations in the mainstem decreased by 24%, while DO concentrations increased by 2.8%. There were no significant impacts on Chl-a concentrations in the mainstem of the river. Finally, for a scenario where extremely low dissolved oxygen release from Mosul Dam in the summer, it was found that approximately 50 km below Mosul Dam was affected before DO concentrations reached an equilibrium concentration. For further work on the Tigris River system, it is recommended to model the Tigris River from Kut Barrage to the confluence with the Euphrates River, about 400 km long, and connect it with the current model to have a complete model of the Tigris River system from Mosul Dam to the confluence with the Euphrates River. This is necessary to manage water the entire system of the Tigris River and also to provide enough water with good quality in Basra.
1059

Comparison of water quality between sources and between selected villages in the Waterberg District of Limpopo Province; South Africa: with special reference to chemical and microbial quality.

Makgoka, Seretloane Japhtaline January 2005 (has links)
Thesis (MPH)--University of Limpopo, 2005 / Water and sanitation inadequacy is still an environmental health challenge in several regions worldwide and a billion people lack access to safe water, while 2.4 billion people have inadequate sanitation [2]. Assessment of water quality by its chemistry includes measures of elements and molecules dissolved or suspended in water. Commonly measured chemical parameters include arsenic, cadmium, calcium, chloride, fluoride, total hardness, nitrate, and potassium [16]. Water quality can also be assessed by the presence of waterborne microorganisms from human and animals’ faecal wastes. These wastes contain a wide range of bacteria, viruses and protozoa that may be washed into drinking water supplies [21]. Three villages were selected for water quality analysis, based on their critical situation regarding access to water and sanitation: namely, Matlou, Sekuruwe and Taolome villages, situated in the Mogalakwena Local Municipality within the Waterberg district of the Limpopo Province, South Africa. A proposal was written to the Province of North Holland (PNH) and was approved for funding to start with the implementation of those projects, with 20% of each village’s budget allocated for water quality research [26]. This was a cross sectional, analytical study to investigate the chemical and microbial quality of water in Matlou, Sekuruwe and Taolome villages. The study was also conducted to explore methods used by household members to store and handle water in storage tanks. Water samples were collected and analysed according to the standard operating procedures (SOPs) of the Polokwane Municipality Wastewater Purification Plant in Ladanna, Polokwane City of South Africa. The questionnaire used was adopted from the one used for cholera outbreak in the Eastern Cape Province of South Africa. Results show that water from all sources in all the villages had increased total hardness concentration. Water from the borehole in Matlou village had increased number of total coliform bacteria. There were increased total and faecal coliform bacteria in storage tanks samples from Matlou village. Water samples from reservoirs in Sekuruwe and Taolome villages did not test positive for any microbial contamination. Water from xiv informally connected yard taps in Sekuruwe village had increased total coliform bacteria, while increased total and faecal coliforms were found in households’ storage tanks. Water samples from communal taps in Taolome village had minimal number of total coliform bacteria, while water from storage tanks had both increased total and faecal coliform bacteria. Matlou village was the only place with increased nitrate concentration at the households’ storage tanks. While all the villages had microbial contamination, Taolome village had the least number of coliform bacteria in water samples from households’ storage tanks as compared to Matlou and Sekuruwe villages. It is concluded that water from sources supplied by the municipalities are safe to be consumed by humans while water from informally connected taps and households’ storage tanks are not safe to be used without treatment. It is recommended that a health and hygiene education package be prepared for all the villages, so that handling of water from the main source into their storage tanks can be improved. Secondly, it is recommended that water in all sources be treated for total hardness and water in storage tanks in Matlou village be treated for nitrate. Thirdly, it is recommended that water be accessed everyday of the week, so that people do not use unsafe water supplies. / The Province of North Holland, Netherlands.
1060

A measure of service quality on water in Lepelle-Nkumpi Municipality in the Limpopo Province

Shongwe, Nkosinathi Sipho January 2007 (has links)
Thesis (MBA.) -- University of Limpopo, 2007 / The residents of Lebowakgomo in Lepelle-Nkumpi Municipality experience numerous inequalities in relation to water services provision. Some of the residents protest towards the inequalities through refusal to pay for the water services. The confrontational non paying residents field questions which the municipality can hardly answer. The problem of refusal to pay is of the magnitude that recently the municipality had to go house-to-house pleading with the inhabitants to pay if the municipality was to continue to provide water services. The specific objectives of this study were three-fold: (1) to determine water service quality using residents’ perceptions on water services in Lebowakgomo, (2) to determine residents’ expectations and perceptions on water services in Lebowakgomo, and (3) to determine the residents’ perceptions on water service quality and customer satisfaction in Lebowakgomo using age, gender, qualification and suburb. A questionnaire comprising five dimensions, namely, tangibles, reliability, assurance, empathy and responsiveness, was compiled to collect data from three suburbs of Lebowakgomo in Lepelle-Nkumpi Municipality. The original sample size was 120, with 9 becoming spoiled due to missing data. The independent variables comprised age, qualification, suburb and gender. Most of the data were analysed for kurtosis and skewness and with the exception of one variable, the rest of the data did not conform to parametric analysis criteria. The major findings of this study indicated overall negative perceptions of residents’ on four dimensions of empathy, reliability, responsiveness and assurance on water service quality which implied that the residents were dissatisfied with the service and called on management to use SERVQUAL as a valid model of assessment to identify areas requiring immediate attention for service improvement. On the other contra positive it was revealed that the municipality was doing well on the tangibles dimension. ix The study recommended use of SERVQUAL in measuring quality of other services within the constitutional competencies of the municipality and further research to investigate age contribution to service quality.

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