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Water Quality of Cisterns and Underground Dams in Semiarid Regions: Case Study of Afogados da Ingazeira, Pernambuco – Northeast Brazil

FREITAS, D.; MORAIS, M; CABRAL, J.; ROSADO, J.; MELO, G.; SILVA, H.; PEDRO, A.; SELVA, V.
Fonte: Internation Water Association Publicador: Internation Water Association
Tipo: Artigo de Revista Científica
ENG
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75.99%
In semiarid regions water resources are limited and irregularly distributed over space and time. As a result, water scarcity is a reality emphasized by the high evaporation rate recorded in these regions (2000 mm per year). In consequence, the management of water use is a subject that requires priority, especially in the regions where water is a scarce resource. There should be orientation towards its rational use through storage in appropriate places – as cisterns, and underground dams. Additionally, these techniques represent an advantage since they have low costs and can be developed and maintained by individual or community programmes. The social mobilization that occurs with families involved on the construction and maintenance of these structures guaranty the sustainability of these techniques. Although several local populations continued to use water without any treatment, is essential to promote the sanitary security of those waters, which must achieve the human consumption standards, defined on Brazilian legislations. The main goals of this work are: (i) to analyze the maintenance of these structures and the facilities of their implementation; (ii) to calculate the costs involved; (iii) and finally to discuss the importance of improve water quality in cisterns and groundwater dams.

Water Quality Modelling using Artificial Neural Networks and Decision Trees

Couto, Catarina; Vicente, Henrique; Neves, José
Fonte: Institute of Water Management, Hydrology and Hydraulic Engineering – University of Natural Resources and Life Sciences – Vienna Publicador: Institute of Water Management, Hydrology and Hydraulic Engineering – University of Natural Resources and Life Sciences – Vienna
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
76.09%
The water quality at ground zero in a given region largely depends on the nature and the extent of the industrial, agricultural and other anthropogenic activities in the catchments. Undeniably, ensuring an efficient water management system is a major goal in contemporary societies, taking into account its importance to the living organisms health and the need to safeguard and to promote its sustainable use. However, the assessment of the data quality of a dam`s water is being done through analytical methods, which may be not a good way of such an accomplishment, due to the distances to be covered, the number of parameters to be considered and the financial resources that will be spent. Under these circumstances, the modelling of water quality in reservoirs is essential in the resolution of environmental problems, and has lately been asserting itself as a relevant tool for a sustainable and harmonious progress of the populations. This work describes the training, validation and application of Artificial Neural Networks (ANNs) and Decision Trees (DTs) to forecast the water quality of the Odivelas reservoir, in the south region of Portugal, over a period of 10 (ten) years. Two different strategies were followed to build predictive models for water quality. One of them used chemical parameters data (strategy A) while the other one used hydrometric and meteorological data (strategy B). In terms of the former strategy...

Brazil : Managing Water Quality - Mainstreaming the Environment in the Water Sector

Margulis, Sergio; Hughes, Gordon; Gambrill, Martin; Azevedo, Luiz Gabriel T.
Fonte: Washington, DC: World Bank Publicador: Washington, DC: World Bank
EN_US
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66.18%
This study examines how environmental issues have been addressed in the water sector in Brazil, within the context of activities of the Federal Government, generally, and those implemented under Bank sector operations, in particular. The core focus of the study lies in the management of water quality, as it affects both the users of raw water, and those who are primarily concerned with the disposal of wastewater. The report considers the following three sectoral areas concomitantly - water resources management, water supply and sanitation, and, the environment - thus limiting its review, and focus to those themes which are key to the over-arching issue of water quality. Water resources management in the country relied upon heavy investments in medium, and large scale projects that provided basic infrastructure for water uses. However, these have produced questionable impacts in terms of reducing poverty, and inequality. One of the reasons for this, has been the poor infrastructure management, which despite its importance...

Water Quality Modeling : A Guide to Effective Practice

Palmer, Mervin D.
Fonte: Washington, DC: World Bank Publicador: Washington, DC: World Bank
Tipo: Publications & Research :: Publication; Publications & Research :: Publication
ENGLISH; EN_US
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66.2%
This report serves as a guide to the utility and relevance of water quality prediction modeling. It draws upon examples from recent World Bank water resources and wastewater management projects. The goal of the guide is to provide a broad-based understanding of the water quality prediction process and to evaluate the relative merits and cost-effectiveness of using water quality models under field conditions. The guide build on and revises the chapter on water quality modeling prepared for the World Bank's "Pollution Prevention and Abatement Handbook, 1998 (report no. 19128)." The guide comprises five sections. Chapter 1 provides a general overview of the use of water quality models, including the objectives of water quality modeling, the approach to water quality prediction, the costs of modeling processes, and the general components of typical water quality models. Chapter 2 discusses the most common water quality parameters that are modeled, the receiving water processes, quality assurance and control for the water quality data and model predictions...

Water quality in lakes and reservoirs in China

Luheng, Yan
Fonte: Instituto Politécnico de Lisboa Publicador: Instituto Politécnico de Lisboa
Tipo: Dissertação de Mestrado
Publicado em /02/2015 ENG
Relevância na Pesquisa
66.19%
China is the world's most populous country with over 1.35 billion inhabitants; also in area, China is one of the world's largest countries. However, the distribution of water resources in the whole territory of China is not homogeneous and there are increasingly severe water shortages, particularly in the north-east of the country. Over the past decade, the water quality of lakes and reservoirs in China has degraded due to many causes, especially the large population. Water pollution and destruction of aquatic ecosystems have caused massive damage to the functions and the integrity of water resources. Roughly, 298 million Chinese in rural areas do not have access to safe drinking water, and 40% of China's rivers were, by 2011, polluted by industrial and agricultural waste. The aim of this study is to identify the most common water quality problems in lakes and reservoirs in China and to analyze the variables that control the water quality, based on research on scientific publications, international journals databases, Google maps, and other available sources of information. After the initial literature research, 58 papers were selected; they described the conditions of 52 water bodies. This information was summarized in a Table with the most relevant characteristics...

Water quality issues in rivers, lakes and reservoirs in Asian countries: an approach to the problems and the methodologies

Jing, Tian
Fonte: Instituto Politécnico de Lisboa Publicador: Instituto Politécnico de Lisboa
Tipo: Dissertação de Mestrado
Publicado em /09/2013 ENG
Relevância na Pesquisa
66.18%
Water covers over 70% of the Earth's surface, and is vital for all known forms of life. But only 3% of the Earth's water is fresh water, and less than 0.3% of all freshwater is in rivers, lakes, reservoirs and the atmosphere. However, rivers and lakes are an important part of fresh surface water, amounting to about 89%. In this Master Thesis dissertation, the focus is on three types of water bodies – rivers, lakes and reservoirs, and their water quality issues in Asian countries. The surface water quality in a region is largely determined both by the natural processes such as climate or geographic conditions, and the anthropogenic influences such as industrial and agricultural activities or land use conversion. The quality of the water can be affected by pollutants discharge from a specific point through a sewer pipe and also by extensive drainage from agriculture/urban areas and within basin. Hence, water pollutant sources can be divided into two categories: Point source pollution and Non-point source (NPS) pollution. Seasonal variations in precipitation and surface run-off have a strong effect on river discharge and the concentration of pollutants in water bodies. For example, in the rainy season, heavy and persistent rain wash off the ground...

The effect of water quality on demand for safe drinking water in rural and peri-urban Cambodia

Fonte: Universidade Duke Publicador: Universidade Duke
Tipo: Masters' project
Publicado em 20/04/2012
Relevância na Pesquisa
66.22%
Executive Summary Policy Question How does perceived drinking water quality affect household willingness to pay (WTP) for clean water in rural Cambodia? Background Inadequate access to improved water and sanitation in the developing world continues to be a major public health and development challenge. UNICEF estimates that nearly 2 million child deaths are attributable to diarrhea (UNICEF, 2008). The excessive burden of diarrhea-related morbidity and mortality is partly attributable to inadequate access to safe drinking water. Poor access to high-quality and convenient water sources may partly be a problem of low demand (Whittington et al., 2009). In fact, there is relatively limited evidence in the literature on demand for water and sanitation services. In this paper, we consider the demand for improved water quality only (rather than changes in both quality and convenience) in two communities in Kandal province, Cambodia. Importantly, many households in these communities already have access to convenient sources of water, either in the form of private connections to piped water networks, or via rainwater harvesting and storage where they live. These sources, however, are of variable quality, and water treatment, both at the system or household-level...

Phase III Report: Christina Basin Water Quality Management Strategy

Kauffman, Gerald J.; Greig, Dan; Bowers, Janet
Fonte: Institute for Public Administration, Water Resources Agency Publicador: Institute for Public Administration, Water Resources Agency
Tipo: Relatório Formato: 4155014 bytes; application/pdf
EN_US
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75.99%
This report summarizes the Phase III work of the Christina Basin Water Quality Management Committee during 1998. The Phase I and II Report published in May 1998 summarizes the work of the Christina Basin Water Quality Management Strategy during the years 1994 through 1997.; The Section 319 of the Clean Water Act programs of the Environmental Protection Agency, Delaware Department of Environmental Protection, and Pennsylvania Department of Environmental Protection provided funding for the programs described in this report.

Monitoring drinking water quality in South Africa: Designing information systems for local needs

Rivett,Ulrike; Champanis,Michael; Wilson-Jones,Toni
Fonte: Water SA Publicador: Water SA
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/30/2013 EN
Relevância na Pesquisa
76.13%
In South Africa, the management and monitoring of drinking water quality is governed by policies and regulations based on international standards. Water Service Authorities, which are either municipalities or district municipalities, are required to submit information regarding water quality and the management thereof regularly to the national Blue Drop System (BDS). Since 2009, a trend has emerged in which urban municipalities have been shown to consistently improve their water quality management whilst some of the rural and under-resourced municipalities are falling behind. A major concern has been that rural municipalities are failing to report the required information and are not complying with some of the regulator's requirements that speak to the overall management of water quality monitoring rather than the actual water quality itself. This paper reflects on a case study undertaken in four rural municipalities in South Africa where a cellphone-based information system was implemented to collect information relevant to the municipality. The study was conducted by the Information for Community Oriented Municipal Services (iCOMMS) research team based at the Department of Civil Engineering at the University of Cape Town. The hypothesis for the research was that improved information flow within rural municipalities - from water supplies in outlying areas to the municipal government office - can improve the efficiency of existing monitoring...

Investigation of potential water quality and quantity impacts associated with mining of the shallow Waterberg coal reserves, west of the Daarby Fault, Limpopo Province, South Africa

Bester,M; Vermeulen,PD
Fonte: Water SA Publicador: Water SA
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/10/2010 EN
Relevância na Pesquisa
76.09%
From South African and international experience, it is known that coal mining has a pronounced impact on surface and groundwater quality and quantity. The influx of water may be as low as 1% of rainfall for underground mines to as much as 20% for opencast mines. Such differences may influence the quantity and quality of surface water and groundwater resources at the local scale and further afield. The Waterberg coal reserves represent the only area with proven coal reserves which are still available for development in South Africa. These reserves are targeted for large-scale mining in the near future, and are situated in a relatively dry part of South Africa. In view of the low rainfall and limited surface water resources, the necessary level of safeguard measures to ensure the quantity and quality of existing water resources is unclear. Experience from other areas cannot necessarily be extrapolated directly. A scoping level study was performed to consolidate the existing information on the geohydrology and pre-mining water quantity and quality of water resources associated with the Waterberg coal reserves. New data regarding water quality and acid-base potential for the different geological areas (through field investigations) and geology and mining methods were obtained. Findings showed a significant likely impact on groundwater resources...

Overview of the influences of mining-related pollution on the water quality of the Mooi River system's reservoirs, using basic statistical analyses and self organised mapping

Barnard,S; Venter,A; van Ginkel,CE
Fonte: Water SA Publicador: Water SA
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2013 EN
Relevância na Pesquisa
75.99%
The Mooi River catchment, in particular the Wonderfonteinspruit (WFS), has been the subject of a large number of studies regarding significant pollution sources, generally attributed to mining in the area. However, very little is known about the hydrochemistry of the surface water of the Klerkskraal, Boskop and Potchefstroom Dams in the Mooi River catchment. The aim of this study was to identify any hydro-chemical changes that occurred in the water quality of Klerkskraal, Boskop and Potchefstroom Dams during the period 1995 to 2010. Self-organised mapping (SOM) of the data emphasized the influence of mining-related effluents on the quality of the freshwater resources of the Boskop Dam and Potchefstroom Damrelative to Klerkskraal Dam which is located upstream of mining-related influences and which could therefore serve as a reference site. High concentrations of SO4 together with high electrical conductivity (EC) and total dissolved solids (TDS) values were evident in these dams as compared to Klerkskraal Dam. Concentrations of nutrients such as PO4, NH4 and NO3+NO2, were however low in all three reservoirs. In Klerkskraal Dam, which is situated above the confluence of the WFS, a strong direct relationship between EC and total alkalinity (TAL) was exhibited. This suggests that Klerkskraal Dam is still a water source displaying natural unpolluted conditions...

Diatoms as indicators of historical water quality: A comparison of samples taken in the Wemmershoek catchment (Western Province, South Africa) in 1960 and 2008

Harding,WR; Taylor,JC
Fonte: Water SA Publicador: Water SA
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/10/2014 EN
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75.98%
ABSTRACT Historical diatom records provide a means of retrospectively determining water quality and inferring ecological condition in rivers and streams. In this study we re-sampled sites originally sampled 48 years previously. We then determined the scores for the Biological Diatom Index (BDI) and the South African Diatom Index (SADI) for each dataset. The results revealed that the present day conditions in this relatively undisturbed locality were almost identical to those reflected by the samples collected half a century before. This illustrates the value of historical diatom data for the purposes of determining antecedent water quality.

Microbial water quality of treated water and raw water sources in the Harare area, Zimbabwe

Chirenda,Tatenda G; Srinivas,Sunitha C; Tandlich,Roman
Fonte: Water SA Publicador: Water SA
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/10/2015 EN
Relevância na Pesquisa
76.13%
Microbial water quality is an essential aspect in the provision of potable water for domestic use. The provision of adequate amounts of safe water for domestic purposes has become difficult for most municipalities mandated to do so in Zimbabwe. Morton-Jaffray Treatment Plant supplies potable water to Harare City and areas surrounding Harare. This study investigated microbial water quality and the impact of microbial water quality related disasters in the area supplied by the Morton Jaffray Treatment Plant. Questionnaires were distributed to household owners in Harare who receive their water from the Municipality and those who use alternate water supplies. Candidates were randomly selected from their workplace. The raw water quality of Manyame River and its tributaries was assessed. Treated water in households was assessed for microbial quality using hydrogen sulphide test and heterotrophic bacteria plate count. Raw water sources were found to be contaminated by faecal matter. Household water sources tested negative for faecal contamination but positive for heterotrophic bacteria. CFU quantities ranged from 1 to 452 CFU/ml for all samples. The WHO guidelines for domestic water sources state that water used for domestic purposes should not be contain than 100 CFU/ml. Public perceptions of water quality ranged from 'unsafe' to 'highly contaminated'. A decrease in the level of aesthetic appeal resulted in residents resorting to alternative sources such as wells and rivers for their domestic water. The current state of treated water was suitable for domestic use. Pathogen monitoring of domestic water is recommended using the hydrogen sulphide test and R2A agar test.

The impact of water quality on informally-declared heritage sites: a preliminary study

Vos,AT; Cawood,S
Fonte: Water SA Publicador: Water SA
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2010 EN
Relevância na Pesquisa
76.04%
The current study is an attempt to gauge the impact of water quality on 2 sacred sites in the eastern Free State, Mautse and Motouleng, which are informally-declared heritage sites, as well as the consequent implications for matters of living heritage as pertaining to the specific sites. The informally-constituted communities at the sacred sites are dependent on freshwater sources where water use, sanitation and waste disposal are unmanaged activities. The sustainability of informally-declared heritage sites may be uncertain due to factors relating to water quality. Water samples were collected for physical, chemical and biological analyses. The latter comprised algal and bacterial analyses which included testing for concentrations of faecal coliforms, where concentrations above 20 cfu/100 mℓ indicates a significant risk of infectious disease transmission (domestic use) and concentrations above 200 cfu/100 mℓ points to a significant infection risk for young livestock. Water quality is discussed in terms of human, animal and ecological risk, which may threaten the heritage and the economic subsistence based on the heritage at both sites.

A new method for the determination of water quality

Jezierska,Karolina; Gonet,Bolesław; Podraza,Wojciech; Domek,Hanna
Fonte: Water SA Publicador: Water SA
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2011 EN
Relevância na Pesquisa
76.08%
The aim of this study was to develop and test a novel screening method for determining water quality. We hypothesised that L-ascorbic acid would be a good indicator of water quality, due to its sensitivity to pollutants. We investigated the absorption spectra of L-ascorbic acid dissolved at different concentrations in water from different sources. We defined a water quality index (WQI) as the change in maximum L-ascorbic acid absorbance at 265 nm over two arbitrarily chosen time periods, i.e. between the 1st and 10th minutes and 1st and 20th minutes. We found that a high WQI value was significantly associated with low water quality, and vice versa. The proposed technique is a quick, simple and inexpensive method for obtaining a preliminary estimate of water quality.

Dairy farm borehole water quality in the greater Mangaung region of the Free State Province, South Africa

Esterhuizen,L; Fossey,A; Lues,JFR
Fonte: Water SA Publicador: Water SA
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2012 EN
Relevância na Pesquisa
76%
Most dairy farm effluent is discharged onto pastures and land by irrigation and poses a risk of enriching groundwater including borehole drinking water. Nitrate, coliforms and Escherichia coli (E. coli), in particular, may cause disease in humans and animals drinking contaminated water. The aim of this study was to obtain an understanding of the status of borehole drinking water quality, including physical, chemical and microbiological properties, on 75 dairy farms in the greater Mangaung region of the Free State, South Africa. Borehole drinking water samples were collected during autumn and spring of 2009 and the physical, chemical and microbiological parameters analysed and compared to the required standards prescribed by the South Africa National Standards (SANS) 241 of 2006. Most farms were compliant; however for combined nitrate and nitrite N, 37 of the farms exceeded the prescribed limit. Similarly, for total coliforms, 45, and for E. coli, 22 of the farms exceeded the acceptable limits. Nine of the farm boreholes were contaminated by N and E. coli. On two of the farms four of the chemical parameters exceeded the prescribed limits, including those for N; both farms were, however, compliant for E. coli. The results of this study suggest that further research on water and waste management on dairy farms in the Manguang region of the Free State should be conducted.

Class frequency distribution for a surface raw water quality index in the Vaal Basin

Dzwairo,Bloodless; Otieno,Fredrick AO
Fonte: Water SA Publicador: Water SA
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/04/2014 EN
Relevância na Pesquisa
76.15%
A harmonised in-stream water quality guideline was constructed to develop a water quality index for the Upper and Middle Vaal Water Management Areas, in the Vaal basin of South Africa. The study area consisted of 12 water quality monitoring points; V1, S1, B1, S4, K9, T1, R2, L1, V7, V9, V12, and V17. These points are part of a Water Board's extensive catchment monitoring network but were re-labelled for this paper. The harmonised guideline was made up of 5 classes for NH4+ Cl-, EC, DO, pH, F-, NO3-, PO4(3-) and SO4(2-) against in-stream water quality objectives for ideal catchment background limits. Ideal catchment background values for Vaal Dam sub-catchment represented Class 1 (best quality water), while those for Vaal Barrage, Blesbok/Suikerbosrand Rivers and Klip River represented Classes 2, 3 and 4, respectively. Values above those of Klip River ideal catchment background represented Class 5. For each monitoring point, secondary raw data for the 9 parameters were cubic-interpolated to 2 526 days from 1 January 2003 to 30 November 2009 (7 years). The IF-THEN-ELSE function then sub-classified the data from 1 to 5 while the daily index was calculated as a median of that day's sub-classes. Histograms were constructed in order to distribute the indices among the 5 classes of the harmonised guideline. Points V1 and S1 were ranked as best quality water (Class 1)...

The influence of land use on water quality and diatom community structures in urban and agriculturally stressed rivers

Walsh,G; Wepener,V
Fonte: Water SA Publicador: Water SA
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/10/2009 EN
Relevância na Pesquisa
76.11%
Epilithic diatom communities offer a holistic and integrated approach for assessing water quality as they remain in one place for a number of months and reflect an ecological memory of water quality over a period of time. The objective of this study is to use diatom assemblages to distinguish between particular land types and associated water quality impacts that are linked to these land-use patterns. Water quality and diatom community data were collected from sites in the Crocodile and Magalies Rivers (Gauteng and North West Province, South Africa) associated with agricultural, urban and natural (reference) adjacent land use respectively. The data collected were subjected to multivariate statistical techniques to analyse spatial and temporal patterns in water quality (principal component analysis) and diatom community structures (non-metric multidimensional scaling) to elucidate hypothesised differences in community structure per land-use type. Five diatom response indices (Generic Diatom Index, Specific Pollution Sensitivity Index, Biological Diatom Index, Eutrophication/Pollution Index and Percentage Pollution Tolerant Valves) incorporated in the OMNIDIA software were implemented to assess the integrity of diatom communities per land-use type. Principle component ordination of water quality describes 56.6% of the variation in data observed...

On the use of diatom-based biological monitoring Part 1: A comparison of the response of diversity and aut-ecological diatom indices to water quality variables in the Marico-Molopo River catchment

de la Rey,PA; van Rensburg,L; Vosloo,A
Fonte: Water SA Publicador: Water SA
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2008 EN
Relevância na Pesquisa
76.02%
Two main approaches have been followed in using diatoms as bio-indicators in the past few decades namely species diversity indices and aut-ecological indices. This study, based on 102 water quality and epilithic diatom samples from the Crocodile Groot-Marico catchment in South Africa, evaluated both types of indices by establishing how well they reflect changes in water quality. It was found that less of the variation in diversity indices could be attributed to changes in water quality variables than was the case for the aut-ecological indices. Furthermore it was found that species diversity indices tend to be higher at intermediate levels of pollution, rather than at low levels of pollution.

On the use of diatom-based biological monitoring Part 2: A comparison of the response of SASS 5 and diatom indices to water quality and habitat variation

de la Rey,PA; Roux,H; van Rensburg,L; Vosloo,A
Fonte: Water SA Publicador: Water SA
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2008 EN
Relevância na Pesquisa
76.04%
Due to the fact that South Africa is a water-scarce country, integrated water resource management based on sound information is essential. Bio-indicators have provided valuable information for water resource management in recent years and have enjoyed increasing popularity. Bio-indicators especially stepped to the forefront with the realisation that aquatic eco-systems are not only a source of water but also deliver several goods and services, as well as being essential for industrial growth and quality of life of many South Africans. This study aimed to quantitatively test two kinds of biomonitoring tools namely diatom-based (SPI and BDI) and macro-invertebrate based (SASS 5) in order to assess their applicability in South African River systems; and whether any additional information can be gained by using the two tools in tandem. The results showed that diatom indices are affected more by changes in water quality than SASS 5, while SASS 5 displayed a higher dependency on habitat quality, as measured by IHAS, than the diatom indices. It is therefore suggested that the two indices be utilised as complementary indicators for integrated assessment of river health.