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1.
Arch Environ Contam Toxicol ; 80(1): 41-54, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33386942

RESUMO

The focus of the present study was to assess the quality of different drinking water sources, impacts of poor water quality on human health, and to apportion pollution source(s) of the district Bajaur, Pakistan. Drinking water samples (n = 331) were randomly collected from springs, hand pumps, open wells, and tube wells and analyzed for physicochemical parameters including toxic elements, and bacteriological contamination (i.e., Escherichia coli). Furthermore, a questionnaire survey was conducted to record the cases of waterborne diseases in the study area. The results showed that total suspended solids and bacteriological contamination exceeded the permissible limits of the WHO in all four of the water sources. Among the potentially toxic elements, Cd, Pb, and Mn were above the permissible limits of the WHO in some samples. The hazard index for spring water was found to exceed the toxicity level (i.e., HI > 1) set by US EPA for both adults and children, while the sources from hand pumps, open wells, and tube wells were within the safe limit. The order for the overall safety level for water quality in the study area was tube wells > open wells > hand pumps > springs. The pollution source apportionment statistics revealed that both geogenic and anthropogenic activities are the sources of drinking water contamination. The results of the questionnaire survey indicated that reports of waterborne diseases were highest in respondents who took their drinking water from springs, whereas reports of diseases were moderate in respondents taking their water from open wells and hand pumps and lowest in respondents taking their water from tube wells. Based on the findings of the study, the tube well source of water is recommended for drinking water purposes.


Assuntos
Água Potável/normas , Microbiologia da Água/normas , Poluentes Químicos da Água/análise , Poluição da Água/análise , Qualidade da Água/normas , Abastecimento de Água/normas , Adulto , Criança , Água Potável/química , Água Potável/microbiologia , Humanos , Paquistão , Distribuição Aleatória , Medição de Risco , Abastecimento de Água/métodos , Abastecimento de Água/estatística & dados numéricos
2.
Arch Environ Contam Toxicol ; 80(1): 92-106, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33388838

RESUMO

Groundwater is the main sources of water supply for drinking purposes in the Ordos Basin in the northwestern part of China. In order to sustain and protect the quality of groundwater resources, shallow groundwater samples were collected and analyzed to identify the hydrogeochemical characteristics, and to evaluate health risk to human. Cluster analysis showed that the 134 groundwater samples were divided into three classes (i.e., class 1, class 2, class 3). The groundwater types are mostly characterized by SO4-Cl type and SO4 type, mixed HCO3 type. The primary natural mechanisms controlling the chemical compositions are water-rock interaction and evaporation-precipitation. The extremely high concentrations of sulfate could be caused by contamination from pyrite or from infiltration of sulfate from inorganic fertilizers or from wastewater discharges. Results of the assessment of the health risks for ingestion of Cl-, NO3-, F-, Cr, and As in drinking water indicated that the total health risks are beyond the US EPA acceptable level of 10-6 per year for consumption of groundwater sourced from all three cluster classes. The highest risks were for ingestion of arsenic and chromium in groundwater. The highest total risks to adults and children were 1.51 × 10-5 and 2.45 × 10-2 (class 1), 4.12 × 10-4 and 8.98 × 10-3 (class 2), 3.06 × 10-3 and 5.49 × 10-2 (class 3), respectively. The study showed that there is a high risk of health problems among the residents of the Ordos Basin in China that are ingesting contaminated drinking water, with the health risks to children higher than the risks to adults.


Assuntos
Monitoramento Ambiental/métodos , Água Subterrânea , Poluentes Químicos da Água/agonistas , Abastecimento de Água/métodos , Adulto , Arsênico/análise , Criança , China , Fertilizantes , Água Subterrânea/química , Água Subterrânea/normas , Humanos , Medição de Risco , Sulfatos/análise , Poluentes Químicos da Água/análise , Abastecimento de Água/normas
3.
PLoS One ; 15(10): e0239682, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33119587

RESUMO

Groundwater inflow to an underground mine will seriously affect its mining plan and engineering geology safety. Groundwater models are powerful tools commonly used in the mines to develop dewatering strategies. Many mines in the Kolwezi area have been present since the 1950s, and groundwater flow patterns have been significantly influenced by mining activities. A mining plan is developed for an underground mine with overturned syncline strata in Kolwezi, Congo. Previous groundwater models using layered homogeneous media lowered model accuracies. A new three-dimensional groundwater model using FEFLOW, consisting of a combined regionally and locally geology models integrating 16 hydrogeological cross-sections and borehole logging data, are formulated to predict the underground dewatering in the study area. A 31-days pumping tests with 3 pumping wells and 28 observation wells are carried out to estimate the hydrogeological properties. The simulated water level data match the observed data rather well. Under 8 scenarios of possible well designs, the model predicts a possible dewatering capacity greater 23,900 m3/d at the initial stage of mining. The concept of the model and its application can be a reference for other mines with complex geology for mining safety in the region of interest.


Assuntos
Monitoramento Ambiental/métodos , Previsões/métodos , Água Subterrânea/análise , Simulação por Computador , República Democrática do Congo , Análise de Elementos Finitos , Geologia/métodos , Mineração/métodos , Abastecimento de Água/métodos
5.
PLoS One ; 15(7): e0234974, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32663202

RESUMO

The objective of this study was to identify and describe the experience of family farmers and their respective families after using the Boardwalk Cistern rainwater collection system and consequent impacts on nutrition profile and food security. This is a qualitative-quantitative study conducted in two municipalities in the semi-arid region of the state of Alagoas, northeastern Brazil. A structured questionnaire was applied to collect information on demographic and socioeconomic status and household access to food, based on the Brazilian Food Insecurity Scale of 29 family farmers' households. Food intake was assessed by food intake markers of the Ministry of Health, while nutritional status was determined by measuring the weight and height of all family members and waist circumference of adults. Nutrition diagnosis was performed using the cutoff points of body mass index for age. Three focus groups were conducted, and the information collected was analyzed through Content Analysis with the aim of knowing the participants' perception of the effects of the received water equipment. The study showed a high prevalence of excess weight (52.7%) and high risk for cardiovascular diseases (35.9%) marked by a high salt and sugar in the food intake. Food Insecurity Scale showed that food insecurity is a problem occurring in 75% of these families. However, focus groups showed that families have a positive perception of Boardwalk Cisterns for their food security. They believe that agricultural production has improved, thereby offering a wider range of foods and, consequently, improving food security. In conclusion, this study highlights the importance of water access programs for food production within public policies to guarantee FNS.


Assuntos
Equipamentos e Provisões , Características da Família , Fazendas , Abastecimento de Alimentos/instrumentação , Estado Nutricional , Abastecimento de Água/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Agricultura , Brasil , Criança , Pré-Escolar , Estudos Transversais , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Chuva , Fatores Socioeconômicos , Inquéritos e Questionários
6.
Am J Trop Med Hyg ; 103(3): 1020-1031, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32700668

RESUMO

Typhoid fever transmission occurs through ingestion of food or water contaminated with Salmonella Typhi, and case-control studies are often conducted to identify outbreak sources and transmission vehicles. However, there is no current summary of the associations among water, sanitation, and hygiene (WASH); and food exposures and typhoid from case-control studies. We conducted a systematic review and meta-analysis of case-control studies to evaluate the associations among typhoid fever and predicted WASH or food exposure risk factors (13), and protective factors (7). Overall, 19 manuscripts describing 22 case-control studies were included. Two studies were characterized as having low risk of bias, one as medium risk, and 19 as high risk. In total, nine of 13 predicted risk factors were associated with increased odds of typhoid (odds ratio [OR] = 1.4-2.4, I 2 = 30.5-74.8%.), whereas five of seven predicted protective factors were associated with lower odds of typhoid (OR = 0.52-0.73, I 2 = 38.7-84.3%). In five types of sensitivity analyses, two (8%) of 26 summary associations changed significance from the original analysis. Results highlight the following: the importance of household hygiene transmission pathways, the need for further research around appropriate food interventions and the risk of consuming specific foods and beverages outside the home, and the absence of any observed association between sanitation exposures and typhoid fever. We recommend that typhoid interventions focus on interrupting household transmission routes and that future studies provide more detailed information about WASH and food exposures to inform better targeted interventions.


Assuntos
Surtos de Doenças , Desinfecção das Mãos , Salmonella typhi/patogenicidade , Febre Tifoide/epidemiologia , Febre Tifoide/prevenção & controle , Estudos de Casos e Controles , Microbiologia de Alimentos , Humanos , Razão de Chances , Fatores de Risco , Saneamento/métodos , Febre Tifoide/microbiologia , Microbiologia da Água , Abastecimento de Água/métodos
7.
Artigo em Inglês | MEDLINE | ID: mdl-32525728

RESUMO

Groundwater is a major source of drinking water for millions of people around the world. Over 400 million people in Africa depend solely on it as their main source of water supply. Fluoride is a common contaminant in groundwater. In low concentration (0.5-1.0 mg/L), fluoride is needed by humans for healthy development of bones and teeth, however, a concentration >1.5 mg/L has been linked with several fluorosis and non-fluorosis diseases. Dental and skeletal fluorosis are the major fluorosis diseases commonly reported with the consumption of fluoride-rich water. Although fluoride intake through other pathways such as the drinking of tea and eating of vegetables have been reported, the drinking of fluoride-rich water remains the major pathway of fluoride into humans. Cases of high fluoride levels in groundwater have been reported in almost all the sub-Saharan Africa region but it is more prevalent in East African countries, Sudan and South Africa. Although fluoride is present in surface water mostly in the East African Rift Valley across different countries in East Africa, its significant or high levels are usually associated with groundwater. Geogenic sources such as fluorite, apatite, biotite, amphibole, micas, topaz, cryolite, muscovite and fluorspar have been identified as the major sources of fluoride in groundwater. High fluoride levels have been reported across sub Saharan Africa, with generally higher levels in East Africa resulting from the volcanic activities in the rift system. Dental fluorosis has been reported in many sub-Saharan African countries including South Africa, Tanzania, Uganda, Ethiopia, Kenya, Sudan, Niger, Nigeria, Benin, Ghana and Malawi. Geothermal temperature has been regarded as one of the driving forces for high fluoride levels recorded in groundwater from deep aquifers and geothermal springs. The most affected people with the consumption of fluoride-rich water are the poor with low socioeconomic status who live in rural areas. Some of the proposed alternative sources include rainwater and fog water harvesting and blending of water from various sources. Low-cost and sustainable deflouridation technique remains one of the best ways to treat fluoride contaminated water either at communal level or at the point-of-use.


Assuntos
Fluoretos/toxicidade , Sedimentos Geológicos/química , Água Subterrânea/química , Poluentes Químicos da Água/toxicidade , Abastecimento de Água/métodos , África ao Sul do Saara/epidemiologia , Fluoretos/análise , Fluorose Dentária/epidemiologia , Fluorose Dentária/etiologia , Água Subterrânea/normas , Humanos , Prevalência , Poluentes Químicos da Água/análise , Abastecimento de Água/normas
8.
Artigo em Inglês | MEDLINE | ID: mdl-32567990

RESUMO

Surface and groundwater resources in the Seridó Region (Brazilian semiarid) were investigated to evaluate their current quality conditions and suitability for domestic use. The water was characterized in terms of physical, chemical, and radiological parameters; including those required by the Brazilian Drinking Water Quality Standard (DWQS). Information about major and trace elements and radiological aspects of the water are reported for the first time. Salinization was confirmed as a key problem in the region, driven natural and anthropogenic. Overall, water has poor organoleptic characteristics. The concentration of most trace elements was below the recommended level, except for uranium and selenium in groundwater. Gross alpha and beta activities higher than the recommended levels were also recorded in several water samples, mostly from the investigated aquifers. In these samples, a detailed radionuclide analysis is required to estimate the effective dose received by the local population. Overall, the results show that water from the investigated region is not suitable for human consumption unless proper treatment is applied. Water requires proper treatment to decrease the content of dissolved salts, toxic elements, and radionuclides responsible for the high gross alpha and beta activities.


Assuntos
Água Potável , Poluentes Químicos da Água/análise , Poluentes Radioativos da Água/análise , Qualidade da Água , Abastecimento de Água/métodos , Brasil , Água Potável/química , Água Potável/normas , Água Doce/química , Água Subterrânea/química , Humanos , Radioisótopos/análise , Selênio/análise , Oligoelementos/análise , Urânio/análise , Abastecimento de Água/normas
9.
PLoS One ; 15(6): e0234307, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32569328

RESUMO

We identified the key sectors of water resource use in China from the perspective of the water footprint to improve the use of water resources. The empirical results showed that there were six key sectors (including Crop Cultivation; Forestry; Livestock and Livestock Products; Fishery, Technical Services for Agriculture, Forestry, Livestock and Fishing; Other Food Products, and Scrap and Waste) for water consumption in China in 2015.We analyzed the use of green water, blue water, and grey water. These six sectors accounted for 66.15% of the total impact and 90.76% of the direct impact. Seven key sectors (the six sectors above plus Steel Processing)for the consumption of blue water in China can explain 59.70% of the total impact and 86.94% of the direct effect in 2015. Eight key sectors (Crop cultivation, Other food products, Scrap and Waste, Railway Freight Transport, Highway Freight and Passengers Transport, Water Freight and Passengers Transport, Pipeline Transport, and Health Services) responsible for the consumption of grey water in China in 2015 can explain 81.28% of the total impact and 95.73% of the direct impact. Therefore, the Chinese government should focus on the departments that manage water resources in these sectors when designing water-saving policies and improving water-use efficiency, such as promoting water-saving irrigation technology (including sprinkler irrigation and drip irrigation) in the agricultural sector.


Assuntos
Conservação dos Recursos Naturais/métodos , Recursos Hídricos/provisão & distribução , Abastecimento de Água/métodos , Irrigação Agrícola/métodos , Agricultura/métodos , China , Produtos Agrícolas , Agricultura Florestal , Água/análise
10.
PLoS One ; 15(6): e0234621, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32544207

RESUMO

Recent studies on water demand management show that providing visual information on water usage along with social comparisons with neighbouring households resulted in more efficient water usage. However, social comparisons can be discomforting for participants, especially in the case of downward or negative evaluations. To avoid this, some studies promote the use of social identity, a social norm approach that avoids comparisons. Past studies using social comparison used infographics, whereas other study types have used only textual (non-graphic) information. Therefore, in this study, we created a visualisation of water usage to highlight the importance of water as a shared resource, that is, as a public good, and feedback over six months according to the participants' water usage. A difference-in-difference analysis indicated that the feedback was marginally significant in decreasing water consumption immediately and continuously, especially for the middle and low use households, during the summer months, which is a period of perceived water shortage. From the questionnaire survey, we found that households felt that they determined their water usage based on their preference and were satisfied with the outcome.


Assuntos
Gestão da Saúde da População , Recursos Hídricos/provisão & distribução , Abastecimento de Água/métodos , Economia , Humanos , Identificação Social , Inquéritos e Questionários
11.
PLoS One ; 15(5): e0232751, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32374769

RESUMO

Insufficient water resources restrict wheat production in the North China Plain, so it is urgent and essential to improve the border irrigation performance and water use efficiency. This study developed a predesigned varied-discharge irrigation scheme in the closed-ended border. Field treatments, including continuous-discharge (CD), increased-discharge (ID) and decreased-discharge (DD) border irrigation tests, were conducted to evaluate the irrigation performance of the proposed varied-discharge scheme. The DD border irrigation treatment had great application efficiency (AE), distribution uniformity (DU) and requirement efficiency (RE), and its comprehensive evaluation indicator (Y) was also significantly higher than other treatments. DD treatment achieved the average AE, DU, RE and Y values of 91.4%, 95.5%, 99.5% and 95.4%, respectively. Furthermore, the hydraulic simulation model WinSRFR was used to optimize the scheme of predesigned varied-discharge border irrigation, and sensitivity analyses of infiltration parameters, roughness coefficient, slope and inflow rate were carried out. The results indicate that the predesigned varied-discharge border irrigation scheme can improve the irrigation performance, and the DD border irrigation scheme has more satisfactory robustness than that of the ID border irrigation scheme.


Assuntos
Irrigação Agrícola/métodos , Água Subterrânea , Triticum/crescimento & desenvolvimento , Recursos Hídricos/provisão & distribução , Abastecimento de Água/métodos , China , Humanos , Modelos Teóricos , Estações do Ano , Solo , Água
12.
Brasília; Organização Pan-Americana da Saúde; abr. 1, 2020. 3 p.
Não convencional em Espanhol, Português | LILACS | ID: biblio-1096206

RESUMO

Os responsáveis pelos serviços de água e saneamento têm um papel relevante na prevenção e controle do vírus causador da doença COVID-19, e é importante que o abastecimento de água, saneamento e higiene sejam gerenciados com segurança, garantindo o cumprimento das regulamentações nacionais. Recomenda-se ativar os mecanismos de coordenação entre os diferentes setores relacionados à água e saneamento, tais como: saúde, educação, habitação, meio ambiente, municípios, instituições governamentais e reguladoras, para facilitar ações conjuntas, oportunas e de maior impacto.


Los responsables de agua y saneamiento tienen un rol relevante en la prevención y control de COVID-19, por lo que es importante que los servicios de agua, saneamiento e higiene sean gestionados de forma segura, garantizando el cumplimiento de las normativas nacionales.


Assuntos
Pneumonia Viral/prevenção & controle , Abastecimento de Água/métodos , Saneamento/instrumentação , Infecções por Coronavirus/prevenção & controle , Pandemias/prevenção & controle , Betacoronavirus
14.
PLoS One ; 15(3): e0230549, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32208442

RESUMO

Urban stormwater is increasingly being considered a viable alternative water supply in California and throughout the southwestern U.S. However, current economic analyses of stormwater capture do not adequately examine differences in stormwater project types and do not evaluate co-benefits provided by the projects. As a result, urban stormwater capture is undervalued as a water supply option. To advance economic analyses of stormwater capture, we determined the levelized cost of water in U.S. dollar per acre-foot of water supply (AF; 1 AF = 1233.5 m3) for 50 proposed stormwater capture projects in California, characterizing the projects by water source, process, and water supply yield. In addition, we incorporated reported co-benefits of projects into the analysis to determine the net benefit of proposed projects. Proposed urban stormwater capture projects were more expensive than non-urban stormwater capture projects on a per-volume basis ($1,180 per AF and $531 per AF, respectively); however, this was primarily driven by the relatively large size of the non-urban stormwater capture projects examined. When incorporating the limited number of reported co-benefits of the projects, the expected levelized cost of water from urban stormwater capture projects decreased dramatically. For projects that reported even a limited number of additional benefits, the net levelized cost decreased from $1,030 per AF to $150 per AF, with some of the projects demonstrating a net benefit. Thus, scaling urban stormwater capture projects to capitalize on economies of scale and incorporating co-benefits of projects can dramatically improve the economic feasibility of these projects. This work demonstrates that stormwater capture can present a cost-effective water supply option in California, and that beyond California, fairer comparisons among projects and inclusion of co-benefits can provide decision makers with adequate information to maximize investments in water management.


Assuntos
Chuva , Abastecimento de Água/métodos , California , Conservação dos Recursos Naturais/economia , Conservação dos Recursos Naturais/métodos , Análise Custo-Benefício , Chuva/química , Movimentos da Água , Abastecimento de Água/economia
15.
Artigo em Japonês | MEDLINE | ID: mdl-32213722

RESUMO

OBJECTIVES: The purpose of this study was to evaluate the efficacy of slightly acidic electrolyzed water (SAEW) against the contamination of the water line of dental units and the effects of SAEW on the water line. MATERIALS AND METHODS: The experimental material was a prototype dental unit equipped with a SAEW generator. SAEW is directly supplied to each device or part of this unit system. Experimental SAEW samples were collected from a high-speed handpiece (HS-1), an ultrasonic scaler, and a cup filler of the prototype dental unit. Control samples were taken before and after the prescribed flushing from another high-speed handpiece (HS-2) that is directly supplied with tap water in the same dental unit. The samples were analyzed for free chlorine and heterotrophic bacteria for 7 years to assess the efficacy and effects of SAEW. The substances eluted in SAEW were examined to investigate the effect of SAEW on the water line. A questionnaire survey was conducted on patients on whom dental uints supplied with SAEW were used. RESULTS: SAEW always showed a higher free chlorine concentration than tap water during the observation period of 7 years. In HS-2 supplied with tap water, the free chlorine concentration increased significantly owing to the prescribed flushing. SAEW always showed a significantly smaller number of heterotrophic bacteria than tap water. No abnormal levels values of water line components eluted into SAEW were observed. There were few negative comments from patients on whom dental units supplied with SAEW were used. CONCLUSIONS: SAEW continuously used for 7 years was effective for contamination control in the water line of dental units.


Assuntos
Consultórios Odontológicos , Contaminação de Equipamentos/prevenção & controle , Peróxido de Hidrogênio , Abastecimento de Água/métodos , Fatores de Tempo
16.
BMC Infect Dis ; 20(1): 226, 2020 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-32183745

RESUMO

BACKGROUND: Rapid control of cholera outbreaks is a significant challenge in overpopulated urban areas. During late-2017, Kinshasa, the capital of the Democratic Republic of the Congo, experienced a cholera outbreak that showed potential to spread throughout the city. A novel targeted water and hygiene response strategy was implemented to quickly stem the outbreak. METHODS: We describe the first implementation of the cluster grid response strategy carried out in the community during the cholera outbreak in Kinshasa, in which response activities targeted cholera case clusters using a grid approach. Interventions focused on emergency water supply, household water treatment and safe storage, home disinfection and hygiene promotion. We also performed a preliminary community trial study to assess the temporal pattern of the outbreak before and after response interventions were implemented. Cholera surveillance databases from the Ministry of Health were analyzed to assess the spatiotemporal dynamics of the outbreak using epidemic curves and maps. RESULTS: From January 2017 to November 2018, a total of 1712 suspected cholera cases were reported in Kinshasa. During this period, the most affected health zones included Binza Météo, Limeté, Kokolo, Kintambo and Kingabwa. Following implementation of the response strategy, the weekly cholera case numbers in Binza Météo, Kintambo and Limeté decreased by an average of 57% after 2 weeks and 86% after 4 weeks. The total weekly case numbers throughout Kinshasa Province dropped by 71% 4 weeks after the peak of the outbreak. CONCLUSION: During the 2017-2018 period, Kinshasa experienced a sharp increase in cholera case numbers. To contain the outbreak, water supply and hygiene response interventions targeted case households, nearby neighbors and public areas in case clusters using a grid approach. Following implementation of the response, the outbreak in Kinshasa was quickly brought under control. A similar approach may be adapted to quickly interrupt cholera transmission in other urban settings.


Assuntos
Cólera/epidemiologia , Abastecimento de Água/métodos , Cólera/prevenção & controle , Cidades , República Democrática do Congo/epidemiologia , Surtos de Doenças/prevenção & controle , Água Potável/química , Água Potável/microbiologia , Características da Família , Feminino , Humanos , Higiene , Controle de Infecções/métodos , Masculino , Purificação da Água
17.
PLoS One ; 15(3): e0229767, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32134982

RESUMO

Capture zone equations for a multi-well system in strip-shaped confined and unconfined aquifers with and without regional flow are presented. The aquifer is limited by two parallel boundaries that are either no flow (barrier) or inflow (variable head) so that aquifers with four possible boundary configurations are formed. The wellfield includes any number of extraction or injection wells or a combination of both types. The flow field in the strip-shaped aquifer was converted to its equivalent extensive aquifer using conformal mapping and image well methods. To delineate the capture envelope, the potential, streamline and stagnation point equations were derived using velocity potential theory. The solution permits rapid determination of the effect of number, position and extraction/injection rate of wells, boundary type and direction, and rate of regional flow on the size, shape and pattern of well capture zones. The derived equations are readily extended to water quality and quantity management simulations, as shown by embedding the equations within two optimization schemes, viz., Particle Swarm Optimization (PSO) and Genetic Algorithm (GA), to automatically determine the most efficient wellfield designs for pump-and-treat remediation, contaminant plume containment and pumping policy projects.


Assuntos
Água Subterrânea , Poços de Água , Algoritmos , Água Subterrânea/análise , Movimentos da Água , Qualidade da Água , Abastecimento de Água/métodos
18.
PLoS One ; 15(2): e0228295, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32092062

RESUMO

Urban water systems involve complex interactions between ecological, social and economic factors. Integrated management approaches are needed to achieve multiple policy objectives in the sector and can be pursued at a range of spatial scales. Small-scale integrated water projects are both feasible and valuable in dynamic urban environments in developing countries. This paper develops a method for the prioritization of localities for integrated projects and applies this to the city of Jakarta. A set of indicators is defined following a systems approach, populated, displayed through a dashboard and mapped, and the relationships between indicators are analysed. Indicator-based prioritization allows policy-makers to guide resources to integrated projects to contribute effectively to the achievement of policy goals.


Assuntos
Abastecimento de Água/métodos , Cidades , Conservação dos Recursos Naturais , Água Subterrânea/análise , Qualidade da Água
19.
Artigo em Inglês | MEDLINE | ID: mdl-31903841

RESUMO

This study revealed the status of 2833 Kanchan Arsenic Filters (KAFs), aged 2 months to over 10 years, distributed in Nepal. Thirty percent of the filters were being used, but usage status generally declined 4 years after installation. Lack of use was mostly due to breakage or leaks (74%), which users did not know how to repair. Some 1283 filters (65%) were abandoned, and users returned to drinking arsenic-contaminated water. Water quality tests showed that the average KAF arsenic removal rate was 75%, and 87 and 62% of the samples met Nepal's drinking water quality standards and World Health Organization guidelines, respectively. The KAF arsenic removal amount was significantly influenced by the arsenic and iron concentrations of influent water and KAF type. The concrete square type showed the best performance in usage status and arsenic removal capacity, namely 57 and 83%, respectively. Long-term use of KAFs (more than 4 years) was assumed to be a cause of the decreasing capacity of iron nails to supply ferric hydroxide to influent water, which led to decreased arsenic removal capacity. Thus, replacement of older iron nails may restore the arsenic removal capacity of KAFs.


Assuntos
Arsênico/análise , Água Potável/normas , Filtração/instrumentação , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Abastecimento de Água/métodos , Água Potável/química , Falha de Equipamento , Características da Família , Compostos Férricos/química , Ferro/análise , Nepal , Purificação da Água/instrumentação , Qualidade da Água/normas , Abastecimento de Água/normas
20.
Environ Monit Assess ; 192(1): 60, 2019 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-31863402

RESUMO

Integrated water planning and management face multiple challenges, among which are the competing interests of several water-using sectors and changing climatic trends. This paper presents integrated and non-integrated climate-environment-water approaches for reservoir operation, illustrated with Karkhe reservoir, Iran. Reservoir operation objectives are meeting municipal, environmental, and agricultural water demands. Results show the integrated approach, which relies on multi-objective optimization of municipal, environmental, and agricultural water supply, improves the municipal, environmental, and agricultural objectives by 70, 32, and 65% compared with the objectives' values achieved with the non-integrated approach, which implements a standard operating policy.


Assuntos
Mudança Climática , Monitoramento Ambiental/métodos , Água Doce/química , Recursos Hídricos/provisão & distribução , Abastecimento de Água , Agricultura , Irã (Geográfico) , Abastecimento de Água/métodos , Abastecimento de Água/normas
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