Source Of Drinking Water Supply Research Articles

Study of the technogenesis of the Degtyarsky mine by audio-magnetotelluric express sounding

The audio-magnetotelluric express sounding was performed at four sections crossing the mine field of the currently not functioning Degtyarsky mine. Field measurements were carried out by a universal broadband receiver “OMAR-2m” with active electromagnetic field sensors developed at the Institute of Geophysics UB RAS. Based on the obtained data, deep sections of the electrophysical parameters of the medium – apparent resistivity and effective longitudinal conductivity – are drawn. The nature of the geoelectric structure of the section allows mapping of the major lithochemical contamination plume and identifying the tectonic disturbance zones that drain aggressive mine waters. The mine waters of the Degtyarsky mine are a source of dangerous technogenic pollution. Despite the neutralization of surface runoff, underground routes of acidic water migration occur along tectonic cracks, primarily in the zone of the regional Serovsko-Mauksky fault. Tectonic zones in the mine area contain contaminated fissure-vein water, which is transited at a depth of 70 to over 200 m. Discharging ascending springs of such waters can be located at a great distance from controlled hydrological objects and pollute sources of drinking and household water supply. Urban development in the western and eastern parts of Degtyarsk does not fall within the distribution zone of polluted water. The southern part of the city is located beyond the watershed of the mine water flow area, but a danger of local contamination by tectonic disturbance zones remains possible. The worst environmental situation is observed in the northern outskirts of Degtyarsk, which falls into the area of heavy pollution of underground and surface waters. Besides, acidic fumes from the flooded Kolchedanny quarry can affect the health of city residents when emitted to the atmosphere.

Groundwater quality assessment in the Northern and Upper East Regions of Ghana

Groundwater is a major source of drinking-water supply in most developing countries including Ghana. Groundwater samples were collected from boreholes from fifty-seven (57) communities in the Northern and Upper East regions of Ghana between October 2016 and March 2017. Physico-chemical parameters and heavy metals, such as Fe, As, Cd, Pb, Mn, and Zn, were determined to evaluate the chemical status and pollution levels of the groundwater sources. The results showed that temperature, total suspended solids, and fluoride ion in groundwater from both regions have most of their values fall above the World Health Organisation (WHO) acceptable values. The heavy metals results show that Fe, Cd, and As from both regions have values above the WHO acceptable limits for drinking water. The principal component analysis reveals dissolved chemical constituents, dissolution of salts from atmospheric precipitation, and anthropogenic activity as the main sources of the measured parameters within the study area. Single-factor analysis of variance analysis indicated significant differences in data sets within and between the detected parameters. The water quality index (WQI) results showed that 96.30 and 44.80% of groundwater sources in the Northern and Upper East regions, respectively, were poor in quality and hence unsuitable for drinking. Moreover, a significant positive correlation of WQI with As, Cd, and Fe indicates that As, Cd, and Fe have a significant impact on the groundwater quality. The degree of contamination, heavy metal evaluation indices, and heavy metal pollution indices showed that most of the groundwater sources were extremely contaminated. The health risk assessments for As, Pb, and Cd as well as, Cd, and Zn showed HQ > 1 in some of the groundwater sources in the Northern and Upper East regions, respectively, in some of the groundwater sources. The carcinogenic risk for As and Pb exceeded the acceptable limit of 10−6. Hence, it can be concluded that adequate treatment regime is required for safe use of groundwater from the Northern and Upper East regions of Ghana.

Use of Heavy Metal Content and Modified Water Quality Index to Assess Groundwater Quality in a Semiarid Area

Groundwater is a major source of drinking and agricultural water supply in arid and semiarid regions. Poor groundwater quality can be a threat to human health especially when it is combined with hazardous pollutants like heavy metals. In this study, an innovative method involving entropy weighted groundwater quality index for both physicochemical and heavy metal content was used for a semiarid region. The entropy weighted index was used to assess the groundwater’s suitability for drinking and irrigation purposes. Thus, groundwater from 19 sampling sites was used for analyses of physicochemical properties (electrical conductivity—EC, pH, K+, Ca2+, Na+, SO42−, Cl−, HCO3−, TDS, NO3−, F−, biochemical oxygen demand—BOD, dissolved oxygen—DO, and chemical oxygen demand—COD) and heavy metal content (As, Ca, Sb, Se, Zn, Cu, Ba, Mn, and Cr). To evaluate the overall pollution status in the region, heavy metal indices such as the modified heavy metal pollution index (m-HPI), heavy metal evaluation index (HEI), Nemerow index (NeI), and ecological risks of heavy metals (ERI) were calculated and compared. The results showed that Cd concentration plays a significant role in negatively affecting the groundwater quality. Thus, three wells were classified as poor water quality and not acceptable for drinking water supply. The maximum concentration of heavy metals such as Cd, Se, and Sb was higher than permissible limits by the World Health Organization (WHO) standards. However, all wells except one were suitable for agricultural purposes. The advantage of the innovative entropy weighted groundwater quality index for both physicochemical and heavy metal content, is that it permits objectivity when selecting the weights and reduces the error that may be caused by subjectivity. Thus, the new index can be used by groundwater managers and policymakers to better decide the water’s suitability for consumption.

МОНИТОРИНГ ХОЗЯЙСТВЕННОГО ОСВОЕНИЯ ТЕРРИТОРИИ В ПРЕДЕЛАХ ЗОН САНИТАРНОЙ ОХРАНЫ ПОДЗЕМНЫХ ВОДОЗАБОРОВ (НА ПРИМЕРЕ ПЕРВОЙ ЛИНИИ ТОМСКОГО ПОДЗЕМНОГО ВОДОЗАБОРА)

Актуальность работы. Зоны санитарной охраны подземных водозаборов устанавливаются с целью защиты подземных вод эксплуатационных водоносных горизонтов от различных видов загрязнения на расчётный амортизационный срок его эксплуатации. По истечении этого периода или при существенном изменении интенсивности водоотбора производится переоценка запасов и, в случае необходимости, корректировка границ зоны санитарной охраны. На основании проектной документации зоны санитарной охраны источников подземного питьевого водоснабжения вносятся в Единый государственный реестр недвижимости, причем определяемые расчетные границы согласовываются с центром государственного санитарно-эпидемиологического надзора. Несмотря на то, что водозабор является стратегически важным объектом, необходимость учета в реестре границ появилась только в связи с вступлением в силу в 2007 г. Федерального закона № 221-ФЗ. В настоящее время в отношении всех видов зон с особыми условиями использования территории установлен срок внесения необходимых сведений в Единый государственный реестр недвижимости – до 1 января 2022 г. Таким образом, с момента расчета границ зон санитарной охраны до их установления и внесения сведений проходит длительный период времени, в течение которого зачастую может измениться антропогенная нагрузка (увеличивается площадь населенных пунктов, появляются новые объекты инженерной инфраструктуры) на участках с ограниченным режимом землепользования. В связи с этим возникает необходимость организации мониторинга хозяйственной деятельности в пределах зон санитарной охраны подземных водозаборов. На таких территориях необходимо оценивать и прогнозировать изменения компонентов природной среды под воздействием антропогенной нагрузки для получения достоверной информации о состоянии земель и способах обеспечения рационального землепользования. Цель: раскрыть возможности мониторинга динамики хозяйственного освоения территории в пределах зон санитарной охраны первой очереди Томского подземного водозабора. Методы: картометрические исследования на основе геоинформационных технологий, статистический и корреляционно-регрессионный анализы, геоинформационный анализ, метод ландшафтного анализа. Результаты. Приводятся результаты исследований динамики и характера изменений антропогенной нагрузки в пределах зоны санитарной охраны центральной части первой очереди Томского подземного водозабора. Основу фактического материала составляют данные Федеральной службы государственной регистрации, кадастра и картографии по Томской области, банки пространственных данных internet-ресурса Esri maps, положенные в основу картометрического анализа лесопокрытых территорий и границ селитебных территорий. Выявлены тенденции к изменению площади различных видов ландшафтов и границ населенных пунктов в пределах района исследования. Ландшафты данной территории подвергаются изменениям при развитии землепользования и водопользования. Селитебная нагрузка в 2018 г. относительно невелика, ее увеличение происходит, преимущественно, за счет индивидуального жилищного и дачного строительства, а не многоэтажной застройки. Выполнена оценка современной численности населения и дан прогноз её изменения на ближайшую перспективу. Выявлен прирост селитебных территорий по отдельным населенным пунктам. Выводы. Установлено, что в пределах третьего пояса зоны санитарной охраны первой линии Томского подземного водозабора и на прилегающей территории за исследуемый период существенно возросла антропогенная нагрузка на природную среду за счет увеличения площади населенных пунктов. Рост произошел за счет освоения участков для индивидуального жилищного строительства, что может повлечь загрязнение водоносных горизонтов из-за неправильно оборудованных индивидуальных систем водоотведения. Показано, что вблизи существующей границы ЗСО активно ведется многоэтажная застройка, что может в целом оказать негативное влияние на состояние отдельных элементов ландшафта, в том числе и на подземные воды. Таким образом, на примере Томского подземного водозабора сделан главный вывод о том, что необходима организация и проведение мониторинга хозяйственного освоения территории в пределах зон санитарной охраны подземных водозаборов. Требуется отрегулировать процедурные вопросы внесения сведений в Единый государственный реестр недвижимости в кратчайшие сроки после выполнения работ по оценке и переоценке запасов подземных вод для установления границ зон санитарной охраны и вступления в юридическую силу ограничений хозяйственной деятельности на данной территории.

Assessment of Uranium Concentrations in Drinking Water Supply Sources Based on the Results of Laboratory Analysis of 238U and 234U Specific Activities and Laboratory Determination of Uranium According to GOST R 54499–2011

Introduction. The cause of toxicity and damaging effects of uranium and its compounds on the body lies in radioactivity of uranium isotopes and their decay products as well as their high chemical activity. In view of the above, we conducted parallel studies of specific activities and concentrations of uranium in household and drinking water supply sources. Materials and methods. We studied specific activities of uranium-234 and uranium-238 in the centralized drinking water supply sources of the Republic of Khakassia exceeding control levels in terms of specific total alpha activity (Aα) and converted them to mass concentrations of uranium. Parallel analyses of uranium concentrations in water using the luminescent method according to GOST R 54499–2011 were performed. Results. Our assessment of the radionuclide composition of centralized drinking water supply sources showed that Aα levels exceeding control levels were largely due to natural radionuclides uranium-238 (contribution up to 25%) and uranium-234 (contribution up to 69%). Based on the specific activities of uranium-234 and uranium-238, we estimated masses (concentrations) of uranium in water ranging from 0.007 to 0.06 mg/L depending on the water source. In the parallel tests of water samples according to GOST R 54499–2011, uranium concentrations ranged from 0.007 to 0.061 mg/L. Conclusions. The uranium concentrations in the republican centralized drinking water supply sources estimated on the basis of uranium-234 and uranium-238 specific activities differed from the concentrations of uranium measured by the luminescent method according to GOST R 54499–2011 within the error of the test method. In some settlements uranium concentrations in water exceeded the hygienic standard of 0.015 mg/L (GN 2.1.5.2280–07).

Typology of the Phytoplankton Community of Dohou Lake, Drinking Water Supply Source in Duékoué Town (Western Côte d’Ivoire)

The objective is to study the phytoplankton community of Dohou Lake in order to contribute to the knowledge of its ecological quality. For this purpose, monthly samplings were carried out annually between October 2017 and September 2018. The studied physicochemical parameters (Temperature, Electrical conductivity, pH, Dissolved oxygen, Transparency, Depth, Total nitrogen, Nitrate, Nitrite, Total phosphorus) varied significantly over time. During the rainy season months, Dohou Lake is influenced by high values of total phosphorus, total nitrogen, conductivity, nitrate, pH, transparency and depth. However, in the dry season, the lake is characterized by high values of temperature, nitrite, dissolved oxygen and conductivity. For the phytoplankton community, 373 phytoplankton taxa divided into 111 genera, 51 families, 24 orders, 11 classes and 7 phyla (Chlorophyta, Euglenophyta, Cyanobacteria, Bacillariophyta, Pyrrophyta, Chrysophyta and Xanthophyta) have been identified. Chlorophyta with 50.67% is the most represented in the taxonomic richness of the environment. Total phytoplankton densities oscillate between 100 105 cells / L (August) and 321 105 cells / L (February) with high proportions of Cyanobacteria greater than 45% during each month of the rainy season. The highest values of Shannon and Equitability diversities are observed during the dry season months.

ОЦЕНКА КАЧЕСТВА ГРУНТОВЫХ ВОД ДОЛИНЫ РЕКИ ВАЛЕРИК АЧХОЙ-МАРТАНОВСКОГО РАЙОНА ЧЕЧЕНСКОЙ РЕСПУБЛИКИ

The main sources of drinking and domestic water supply in the Chechen Republic are groundwater. The scares information on the intensity of pollution and the elemental composition of groundwater in the republic, as well as the heterogeneity of the distribution of chemical elements, largely associated with the presence of mountain areas, determines the necessity of detailed investigations. Water chemical and elemental composition of springs situated in the Valeric river valley at the Valeric settlement territory, Achkhoy-Martan district of the Chechen republic, is studied. All water samples were alkaline (pH 8.12–8.77), with relatively low levels of hardness (2.1–3.0 mg-eq/dm3) and mineralization (213–441 mg/dm3) and low fluorine content (0.28–0.36 mg/dm3). Among the studied indicators, risk factors are an increased content of nitrates (indicated concentration range reached 0.67–1.33 MPC). Water of springs situated at the river downstream contained significantly higher concentrations of all elements investigated. The highest coefficients of variations were revealed for B (84.6%), Cu (85.8%), Se (103%), and also As (86.5%) and Cd (96.7%). Three springs with elevated levels of B (730 µg/dm3), Li (210 µg/dm3) and Se (1.0-4.2 µg/dm3) were revealed, This suggests high prospects of bottling the water of these springs for utilization in preventive purposes as a table natural mineral water, intended for increasing immunity, preventing osteoporosis and in neurological practice.

Chemical and Toxicological Analysis of Territories Affected by Radiation and Chemical Pollutants: II. Toxicity Effects of Natural Water (in vitro Studies)

The toxic properties of native water samples of surface (river) water and groundwater used to meet drinking water needs in settlements of the Zhizdrinskii and Ul’yanovskii districts of Kaluga Oblast, which were the areas most exposed to radiation after the accident at the Chernobyl nuclear power plant in 1986, are studied. The focus is on manifestations of genotoxic effects, as the most typical effects of radiation pollution of the territory. It is shown that water exhibits, in most of the analyzed samples, a reliable cytogenetic effect in relation to cells of transplanted cultures of the Chinese hamster (CHO and 237 clones). At the same time, the extractable ether-soluble organic substances contained in the analyzed water samples exhibit genotoxic activity only after they are concentrated by a factor of 100. In parallel, the mutagenic toxicity of water samples was analyzed using the Ames test. Without metabolic activation (in the absence of additions of the S9 fraction of the rat liver), most water samples from the drinking water supply sources show an acute toxicity to Salmonella strains (TA 97, TA 98, and TA 100). The results of biological tests are discussed in relation to previously obtained data on the radiation effects of the Chernobyl accident on the aquatic environment of the Dnieper reservoirs. It is concluded that the principal role in the manifestation of genotoxic properties may be played by radioactive isotopes that are hidden from traditional methods of radiation monitoring and are sources of alpha and beta radiation that lead to the formation of metal ions in the superoxidized state in the presence of environmental pollution by transition metals, in particular, to the formation of microcolloidal particles of mixed-valence manganese Mn(III, IV) that serve as carriers for the OH radical. The acute and chronic toxicity of the analyzed river and groundwater samples is established by bioassay methods using test organisms of various trophic levels (bacteria, ciliates, and Daphnia). No correlation with toxicity is detected in any of the traditionally monitored hydrochemical indices of water quality.

The use of clays materials of the Tyumen region in the treatment of natural and waste water

An assessment was made of the ecological status of water bodies in the South of the Tyumen Region, which play a significant role in the region’s water use and are sources of drinking and industrial water supply. The hydrochemical characteristics of natural waters and the water use conditions that determine the indicators of water quality in water bodies and streams are considered. Critical levels of pollution have been established for zinc, copper, manganese, iron, cadmium, chromium, nickel and aluminum in all water bodies of the Tyumen region. The reasons for optimizing the purification processes at the existing water supply and wastewater treatment facilities in the region are given. The structure and chemical composition of clay materials of the Tyumen region was studied. The efficiency of extraction of nickel ions of kaolin, montmorillonite and mixed kaolin and montmorillonite clays has been investigated. The quantitative characteristics of the process of nickel ion adsorption on all the presented natural clays are obtained. It is established that the mixed natural clay has higher values of exchange capacity in relation to nickel ions. It is noted that the description of the adsorption equilibrium corresponds to the Langmuir model. The possibility of using kaolinite, montmorillonite and mixed clays as a reagent for purifying natural and waste waters at the existing treatment facilities of the Tyumen region is presented.

Choice and quantity demand for improved and unimproved public water sources in rural areas: Evidence from Benin

Almost half of the world's population relies on public water sources for the daily drinking water supply. In this context, usage of improved public water sources is identified as a major contributor to good health. This research aims to identify important determinants of demand for water from improved and unimproved public water sources in rural areas. This is done by estimating choice and quantity models using a unique data set from a household survey conducted in rural areas of Benin, West Africa. The analysis identifies source and household characteristics that increase choice probability and water quantity demand for improved and unimproved public water sources. The price of water, the distance between the household and the water source, and the subjective quality of the source are relevant characteristics for the water source choice. Wealthy households and households with female heads have a higher probability to choose improved public water sources. After households have chosen a public water source, quantity demand is driven by wealth, household size and perceived taste. Price only affects water quantity demand from improved sources, while distance only affects water quantity demand from unimproved sources.

Hydrochemical characterization of shallow groundwater from the Mesta River basin

Groundwater is a valuable natural resource and an important source of drinking and domestic water supply. There are two types of groundwater in the Mesta River Basin: HCO3- > Ca2++Mg2+ (1st type waters) and HCO3- < Ca2++Mg2+ < HCO3-+SO42- (2nd type waters). The waters of the first type formed in the silicate rocks, are widespread in the high mountain, mountain and low mountain area. These waters are attached to the region of regional fracturing of the Precambrian metamorphic complex represented by gneisses, granitogneisses, amphibolites and to the fractured environment of the southern Bulgarian granites and granitoids, quartzites, conglomerates and marls of the Paleozoic. The waters of the second type are characteristic of the valleys covered by Pliocene and Quaternary sediments with minimal precipitation. Groundwater from the Mesta River catchment area is mainly hydrocarbonate-calcium-magnesium with high sodium content in the southern part of the catchment area. The content of anions in groundwater is in the sequence: HCO3- > SO42-> Cl-. The cations are arranged in the order: Ca2++Mg2+ > (Na++K+) or Ca2+ > (Na++K+) > Mg2+. Groundwater is very soft to moderately hard, fresh, with TDS content up to 0.5 g/l and chloride content below 10 mg/l.

MODERN PROBLEMS OF THE APPLICATION OF SANITARY RULES AND NORMS ON THE ORGANIZATION OF SANITARY PROTECTION ZONES OF WATER SUPPLY SOURCES AND WATER PIPES FOR DRINKING PURPOSES

Introduction. Fundamental changes in the political and social infrastructure of the Russian Federation, the active development of the market economy, the assertion of legal statehood turned out The Russian legislation to have entered a qualitatively new state, a notable feature of which was the interdepartmental and intrastructural inconsistency. The sanitary rules on the sanitary protection zones of water supply sources have not passed this fate as a result of the problems of application of the norms of the document into the practice. The purpose of the study: to study of legal acts of the Russian Federation, establishing requirements for the areas of sanitary protection of sources of drinking and domestic water supply, identification of contradictions and development of proposals for amendments and additions to the existing sanitary rules on the areas of sanitary protection of water sources and drinking water supply. Material and methods. The article considers Federal laws and Government resolutions, sanitary rules, and norms, projects of sanitary protection zones of drinking and household water supply sources, literature sources as materials. The methodological basis of the research was the complex of General scientific methods for the study of public relations arising in the field of ensuring the hygienic safety of sources of drinking and economic-household water supply: analysis, systemic-structural, comparative. Results. The paper presents proposals to bring up to date the terms, names, and powers of the parties to the relationship, as well as clarifying the requirements for the composition of the project, its text, and cartographic part. Conclusion. Submitted proposals will create a consistent structure of the constituent elements of the regulated relations, to ensure the symmetry of the standards document with standards that determine the safety of drinking and economic - household water supply of the population in other normative acts. In addition, the proposed changes will form a system of rights and obligations, resulting in the liability for the violation of sanitary norms in the establishment of the boundaries of sanitary protection zones.

SURFACE SOURCES OF CENTRALIZED DRINKING WATER SUPPLY: THEIR PURIFICATION FROM BIOCONTAMINATION AND PURIFIACTION EFFICIENCY DETERMINATION (WITH THE CITY OF SIMFEROPOL TAKEN AS AN EXAMPLE)

The paper demonstrates statistical analysis results of biocontamination of Simferopol water reservoirs of centralized drinking water supply sources. The biocontamination results were obtained by permanganate oxidizability factor. The analysis revealed a consistent patt ern of biocontamination distribution and its analytical description for four sources of centralized water supply. The paper also introduces models of this factor distribution for water purifi ed in water-purifi cation plants of the city of Simferopol (in clean-water reservoirs). The eff ectiveness of two-step water purifi cation scheme (horizontalstrainer chamber - high-rate trickling fi lter) from biocontamination is calculated. The research demonstrates a probability of exceeding permanganate oxidizability normative values for drinking water according to WHO and EU standards and according to drinking water requirements for this indicator in the Russian Federation. The required degree of permanganate oxidizability disposal at water treatment plants which will make the quality of drinking water meet WHO and EU standards is also defi ned.

Identification of nitrate pollution sources of groundwater and analysis of potential pollution paths in loess regions: a case study in Tongchuan region, China

Groundwater is the essential and predominant source of drinking and irrigation water supplies in most arid and semiarid regions, particularly in Loess Plateau of China. The threat to groundwater quality by nitrate pollution has always been of considerable concern in loess regions. In this paper, correspondence analysis, stoichiometric analysis, ratios of major ions and some qualitative analysis are employed to discuss the spatial variability of nitrate (NO3 −), identification of NO3 − pollution sources and its potential pollution paths based on 112 water samples in Tongchuan region on the middle edge of Loess Plateau of China. Results indicate that the NO3 − concentrations ranged from 0.25 to 173 mg/L, 20.54% of water samples exceeded the Standards for Drinking Water Quality from China (≤44 mg/L), and 15.18% of samples exceeded the Guidelines for Drinking Water Quality from World Health Organization (≤50 mg/L); the water samples with high NO3 − concentrations primarily concentrated in river valleys, and the types were mainly pore waters and individual surface waters. Sewage or manure from livestock effluent was the primary sources of NO3 − in some surface waters, pore water samples with high NO3 − were closely related to agricultural input or a mixing process. Groundwater recharges from surface water and vertical infiltration in river valleys with shallow groundwater depth were considered as the potential pollution paths for NO3 − ions in the study area based on nitrate nitrogen distribution in soil profile. Driven by concentration difference and local seepage system, these NO3 − ions diffused around and groundwater buried in great depth was consequently polluted. Therefore, river valleys should be listed as the prior protection areas in loess regions; in addition, the time lag between land use changes and groundwater quality response should also be paid attention to in nitrate pollution prevention, particularly in the thick unsaturated zones.

Potable or Affordable?: A Comparative Study of Household Water Security Within a Transboundary Aquifer Along the U.S.-Mexico Border

The U.S.-Mexico borderlands are a water-scarce region, the result of a dry and variable climate, demographic and economic growth, and asymmetrical development in the transborder region. Generally, this accurately describes the condition of depleted water resources in the rapidly expanding urban conglomerates straddling the international boundary, where 90 percent of the borderlands population resides. The remaining 10 percent of the population, however, lives in small, rural communities that suffer from different and unequal water security challenges. Palomas, Chihuahua (population 5,748), and Columbus, New Mexico (population 1,625), are two adjacent communities that are mutually dependent for their drinking water supply source on arsenic- and fluoride-contaminated groundwater from the transboundary Mimbres Basin Aquifer. This paper examines how these two binational communities have confronted this water security challenge over a twenty-year period and the differences between and within the communities. Using a 1996 survey as a baseline, the analysis also includes a household survey of 152 households, 60 semistructured interviews, and participant observations of water practices during two months of fieldwork in the summer of 2016. Although Palomas and Columbus share a common groundwater resource, this research found that each local water utility adopted a distinct approach to addressing groundwater contamination, predicated on its financial and social resources, and structured by national and binational water policy and institutional parameters. The survey revealed that household water security improved in both communities in terms of water access and reliability. But centralized water filtration technology made water less affordable in Columbus, while decentralized water filtration technology did not resolve household water supply contamination problems in Palomas. This study demonstrates the importance of including water equity within the integrated framework of water security.

Water Quality Assessment in the Selenga River and Its Delta in terms of Sanitary and Microbiological Indices

In 2006–2010 water quality of the Selenga River, including its delta and main tributaries, located within the territory of Russian Federation was assessed and analyzed in terms of sanitary and microbiological indices. Sanitary indicator microorganisms occurred along the whole length of the river, especially in summertime. Analysis of their composition and quantitative indices made it possible to conclude that water quality in the river is significantly deteriorated. In summertime, the water of the Selenga River does not correspond to the requirements of the Russian Federal Standard of Water Quality. It can not be recommended as a source of drinking and household water supply, and also for recreation.

Assessment of Water Quality Status of Guruvayur Municipality

Groundwater is an essential and vital component of our life support system. The deterioration in the groundwater quality due to geogenic and anthropogenic activities has drawn great attention as it is the major alternate source of domestic and drinking water supply. Groundwater and surface water samples collected from various locations in Guruvayur were analysed for selected physico-chemical and bacteriological parameters by adopting APHA standard methods. The results of the analysis indicated the chemical and bacteriological contamination due to the disposal of solid, organic and septic wastes in the surface water samples of Chakkamkandam, Palayur and Edappally which are the various locations in Gurauvayur. Also the groundwater samples of Guruvayur were contaminated. The study revealed that, the water samples examined were found to be above the permissible limits of Bureau of Indian Standards (BIS). The sewage inlets that open directly to the water body are the major source of pollutants. The monitoring of various water bodies indicates the importance of taking appropriate measures to treat the water resources before either discharged to wetlands or consumed by human beings. It is also recommended to continue the monitoring periodically to assess the pollution status of the area.

Erratum to: Optimal design of BP algorithm by ACOR model for groundwater-level forecasting: A case study on Shabestar plain, Iran

Groundwater always has been considered as one of the major sources of drinking and agricultural water supply, especially in arid and semi-arid zones. Thus, there is a need to simulate (i.e., forecast) groundwater levels with an acceptable accuracy. In this paper, we present two applications of intelligent optimization algorithms for simulations of monthly groundwater levels in an unconfined coastal aquifer sited in the Shabestar plain, Iran. First, the backpropagation neural network (ANN-BP) with seven neurons in its hidden layer is utilized to reproduce groundwater-level variations using the external input variables including the following: rainfall, average discharge, temperature, evaporation, and annual time series. In the next application, ant colony optimization is used to optimize and find initial connection weights and biases of a BP algorithm during the training phase (ACOR-BP). The results were found to be acceptable in terms of accuracy and demonstrated that a hybrid ACOR-BP model is a much more rigorous fitting prediction tool for groundwater-level forecasting. This study has shown that such a hybrid network can be used as viable alternative to physical-based models for simulating the reactions of the aquifer under conceivable future scenarios. In addition, it may be useful for reconstructing long periods of missing historical observations of the influencing variables.

Groundwater storage and depletion trends in the Loess areas of China

Groundwater is the essential source of drinking and irrigation water supplies in most parts of the world. The Loess area is one among the largest manufacturers of agricultural merchandise in China and is to a great extent dependent on groundwater for public water supply and irrigation. The effect of expanded open supplies and irrigation on groundwater levels has not been very much investigated, both spatially and temporally. Thus, this study has used remote sensing data from NASA’s Gravity Recovery and the Global Land Data Assimilation Systems to assess the aggregate change in groundwater storage across the Loess area over a period of 13 years, from 2002 to 2014. The results demonstrate that the total groundwater depletion occurred at the rate of 529.73 km3 yr−1, and the mean groundwater consumption rate was −3.89 cm yr−1 between the winter and monsoon seasons during the period of 2002–2014. The most extreme consumption rate occurred during 2004 (−7.60 cm yr−1), while the minimum occurred during 2003 (1.13 cm yr−1). Groundwater consumption at such high rates will prompt unsustainable groundwater levels, bringing about financial anxiety, vulnerability to environmental change and excruciating burdens to sustenance and water security. Careful assessment of spatiotemporal groundwater storage in the Loess area will help China’s water resource managers and policymakers administrate groundwater resources in the future to improve water and food security.

Performance of membrane filtration in the removal of iron and manganese from Malaysia's groundwater

The aim of this research was to investigate the ability of nanofiltration (NF) and ultrafiltration (UF) membranes as a filtration unit for groundwater treatment for drinking water resources. Commercial membranes denoted as TS40, TFC-SR3 and GHSP were used to study the performance based on rejections and fluxes. The investigation has been conducted using natural groundwater obtained from a deep tube well with initial concentration of iron (Fe) and manganese (Mn) at 7.15 mg/L and 0.87 mg/L, respectively. Experimental results showed that NF membranes exhibited higher fluxes than UF membrane with pure water permeability at 4.68, 3.99 and , respectively. For metal rejection, these membranes have performed higher removal on Fe with TS40, TFC-SR3 and GHSP membranes having more than 82%, 92% and 86% respectively. Whereas, removal on Mn only achieved up to 60%, 80% and 30%, for TS40, TFC-SR3 and GHSP membranes respectively. In order to achieve drinking water standard, the membranes were efficient in removing Fe ion at 1 and 2 bar in contrast with Mn ion at 4 and 5 bar. Higher rejection of Fe and Mn were achieved when pH of feed solution was increased to more than 7 as TFC-SR3 membrane was negatively charged in basic solution. This effect could be attributed to the electrostatic effect interaction between membrane material and rejected ions. In conclusion, this study proved that NF membrane especially the TFC-SR3 membrane successfully treated local groundwater sources for public drinking water supply in line with the WHO standard.