Groundwater is a vital resource that provides drinking water to over half of the world's population. However, groundwater contamination has become a serious issue due to human activities such as industrialization, agriculture, and improper waste disposal. The impacts of groundwater contamination can be severe, including health risks, environmental damage, and economic losses. A list of unknown groundwater contamination sources has been developed for the Wang-Tien landfill using a groundwater modeling system (GMS). Further, AI-based models have been developed which accurately predict the contamination from the sources at this site. A serious complication with most previous studies using artificial neural networks (ANN) for contamination source identification has been the large size of the neural networks. We have designed the ANN models which use three different ways of presenting inputs that are categorized by hierarchical K-means clustering. Such an implementation reduces the overall complexity of the model along with high accuracy. The predictive capability of developed models was assessed using performance indices and compared with the ANN models. The results show that the hybrid model of hierarchical K-means clustering and ANN model (HCA-ANN) is a highly accurate model for identifying pollution sources in contaminated water.
Challenges with respect to potable water supply in Vhembe District threaten the health and welfare of local community. This paper is aimed at assessing the challenges and residents’ coping strategies to improve the potable water supply systems in rural areas in Vhembe District Municipality (VDM). Data for this paper was collected from households, councillors, traditional leaders and municipal officials through questionnaires, interviews and focus-group discussions. Qualitative and quantitative research methods were used and thematic content analysis and descriptive statistics were used to analyse data. The results showed that the main sources of water are ground water from boreholes which are used by about 45.3% of the communities, followed by tap water from the dams, by 35.3%, then rivers by 4.0%, fountains by 5.4% and water tankers by 10.0%. Among the identified challenges are: aged water infrastructure, system breakdowns, lack of funding, vandalism of infrastructure and lack of maintenance, operation of infrastructure by unskilled technicians, theft, and non-payment of water services, among others. To cope with water supply challenges, the study recommended that communities play active role in water projects which would include paying of water supply service for its sustainability. They should also play active roles in water committees that will manage, operate and maintain the water supply with the assistance of VDM officials. It was concluded that the rural water supply situation can be improved when communities, government and other relevant stakeholders cooperate and provide solutions and resources.
In Jordan, the unprecedented proliferation of building projects is anticipated to increase the potable water demand in the construction manufacturing. In the present work, secondary treated wastewater (STW) and potable water (PW) were used in the production of concrete mixes, which were subjected to testing after 3 to 28 days of curing to determine how the, mechanical properties of concrete was affected by the addition of secondary treated wastewater in various proportions (25-100%). Results indicated that the use of 25% and 75% of secondary treated wastewater in concrete production increased the compressive strength to 39 MPa after 28 days of curing. A more noticeable increment was recorded in tensile strength, which was double that achieved with the standard design. Overall, the compressive strength increased by 21.95% when secondary treated wastewater was used, while the expenditure related to water usage was halved. Furthermore, there was consistency between the results obtained from scaling up to actual ready-mix concrete production and the results of the empirical work.
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Omówiono koncepcję budowy nowoczesnego systemu filtracji i magazynowania wody w elastycznych zbiornikach do wykorzystania na wypadek powodzi lub innych nieprzewidzianych katastrof naturalnych i technicznych. Zastosowanie wysokowydajnych filtrów wody umożliwi wykorzystanie zanieczyszczonych zasobów wodnych (np. wody popowodziowej lub skażonej), a przy wdrażaniu koncepcji podwójnej filtracji możliwe będzie uzyskanie wody pitnej. Użycie modułów w postaci zbiorników elastycznych znacznie zwiększy mobilność zestawu, który ułatwi budowę stanowisk do uzdatniania wody przy jednoczesnym zaangażowaniu znacznie mniejszych sił i środków niż w przypadku standardowych działań. Przedstawiono stosowane w praktyce stanowiska uzdatniania wody w celu podniesienia jej jakości do poziomu wymagań dla wody pitnej.
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A review, with 47 refs. of mobile water purifn. systems used in world practice. The concept of building a modern water filtration and storage system in flexible tanks for use in the hard to reach areas was presented.
In this research, adsorption followed by filtration was used for removing heavy metals (Cu, Zn, Mn, and Cr) from the polluted water. Three types of soils (silty, sandy and clay) and three types of marble powder (pure, impure, marble-granite mix) were used as an adsorbent. The soil and marble samples were collected from different regions of Oman. The maximum adsorption obtained was 96.01% for Zn using pure marble powder and the minimum adsorption obtained was 6.70% for Mn using impure marble powder. Through different soils, the maximum adsorption of 88.61% was achieved for Zn using clay and the lowest one is for Cr 16.51% using silty soil. The results suggest that among the marble powders, the pure ones show the maximum (96.01% for Zn) and marble-granite show the minimum (Mn 6.70%) adsorption performance. Among the adsorbents, Zn is the best adsorbate (96.01%) while the worst among the group is Mn, which merely adsorbed 6.70% with the selected adsorbents.
The recycling of water treatment residues (WTR) inside drinking water treatment plants (DWTP) to be a good option for reusing this type of waste, as well as for reducing the costs with its disposal off and with the acquisition of treatment chemicals. Therefore, a WTR was reused for auxiliary of the coagulation-flocculation processes for reducing the use of aluminium sulfate (coagulant) in a DWTP. Three series of experiments have been conducted involving three water samples with different turbidity and colour, different WTR samples with different total suspended solids (TSS) concentrations and different aluminium sulfate concentrations. The results showed that WTR can efficiently be used for the removal of turbidity between 21 NTU and 218 NTU and colour between 194 HU and 1509 HU for TSS concentration between 1635 mg/dm3 and 5420 mg/dm3, with better results in the range between 1635 mg/dm3 and 2678 mg/dm3. For higher TSS concentrations, the removal of both parameters decrease because there are excess of organics released to water, which demands the use of more coagulant.
Aluminium is one of the environmental factors that may have an impact on Alzheimer's and Parkinson's disease. Some epidemiological studies show a relationship between the concentration of aluminium in drinking water and the incidence of Alzheimer's disease. The article presents and discusses the results of research on the effect of the type and dose of non-prehydrolyzed aluminium coagulants on the concentration of residual aluminium in water intended for human consumption. Aluminium sulphate (VI) and sodium aluminate were tested as coagulants. Analysis of the obtained test results showed that lower concentrations of residual aluminium were found after coagulation with aluminium sulphate (VI), which is hydrolyzed acidally, lowering the pH of the water in the range of 7.47 to 7.12 providing good conditions for the formation of Al(OH)3. A less useful coagulant due to the concentration of residual aluminium was sodium aluminate, which undergoes basic hydrolysis creating conditions for the transition of Al(OH)3 into soluble Al(OH).
Na ulicach polskich i europejskich miast w ostatnich latach wyraźnie dostrzegalny jest renesans zdrojów wodnych. Obserwując światowe tendencje w projektowaniu przestrzeni publicznej, mozna stwierdzić, że obok ławek, koszy czy lamp ulicznych zdroje stają się nieodłącznym elementem małej architektury.
The geology of the Świętokrzyskie Province is complex and diverse. Potable water is supplied mainly from Devonian, Triassic, Jurassic and Cretaceous aquifers. Approximately 75% of the water is drinkable, the other 25% is contaminated due to human activities. Water found in the Świętokrzyskie Province is of the Ca(HCO3)2 or CaMg(CO3)2 type
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Dzięki możliwości pozyskania funduszy na rozwój infrastruktury wodno-ściekowej Miejskie Przedsiębiorstwo Wodociągów i Kanalizacji w m.st. Warszawie SA zrealizowało i nadal realizuje inwestycje, których przygotowanie poprzedzone było wieloma latami badań modelowych. Inwestycje mające na celu poprawę jakości wody dostarczanej odbiorcom w aglomeracji warszawskiej zrealizowane zostały w ramach II Fazy Projektu Warszawskiego pod nazwą „Zaopatrzenie w wodę i oczyszczanie ścieków w Warszawie’’ oraz nadal są realizowane w ramach Fazy IV.
Nową siedzibę Wydziału Badania Wody Górnośląskiego Przedsiębiorstwa Wodociągów S.A. otwarto 30 września na terenie parku technologicznego „EkoEnergia – Woda – Bezpieczeństwo” w Katowicach. W ramach laboratorium działają 4 pracownie – badań mikrobiologicznych, hydrobiologicznych, sensorycznych i fizyczno-chemicznych (19 pomieszczeń).
Rozmowa z mgr inż. Barbarą Mulik, członkiem Komisji Bezpieczeństwa Zdrowotnego Wody, doradcą ds. bezpieczeństwa i jakości wody, na temat bezpieczeństwa funkcjonowania systemów zaopatrzenia w wodę w odniesieniu do zmian prawa unijnego i polskiego.
The effect of filter media on groundwater quality changes was studied for 6 months. The test system was continuously supplied with groundwater from well, at a constant speed from top to bottom and filter deposits were open to provide contact with air. Filter beds during the study period were not washed. The subject of the study were three beds (Z1, Z2 and Z3) with different filter materials: Z1, Z3 were filled only with an alkaline material, which provided to reduction the corrosivity of water, Z2 – outside alkalising materials also included sand, thus increasing removal efficiency of iron and phosphate ions. Analysis of water physico-chemical parameters include pH, temperature, total alkalinity, intensity of colour, turbidity, dissolved oxygen and the content of: iron, iron (II) and (III), aggressive carbon dioxide, inorganic nitrogen forms (Ninorg), ie NH4+, NO2-, NO3-, phosphate and total organic carbon. Bacteriological analysis of water samples was based on the total number of psychrophilic bacteria, having an optimum temperature for growth about 22ºC, and mesophilic (37ºC). All analyses were made in accordance with current standards. Groundwater was characterized by high volatility of most of the analyzed indicators of water quality. Due to the low flow velocity of water through the filtration beds and presence of dissolved oxygen in water, there was conditions for microbial growth in the deposits. There were a growth conditions for biofilm development on the surface of filter media. Excess filter media was periodically flushed out by flowing water regardless of the type of material which is contacted with water. Confirmation of the biofilm development on the surface of mineral grains was also indirectly by the increase in the number of bacteria in the filtrate, compared to the number of bacteria in the groundwater. Biological activity of the bacteria on the deposits surface was confirmed by changes in concentration of inorganic forms of nitrogen. All three beds have provided a reduction in inorganic nitrogen, which was assimilated by the microorganisms. Microorganisms on the surface of deposits reduced ammonia nitrogen in the filtrates by nitrification process. In addition, NH4+ particles may be adsorbed on the surface of particulate matter present in the water and retained in the bed. During this research there were no significant differences depending on the type of deposit, in efficiency of removal of inorganic nitrogen.
This paper presents an experimental investigation of two incline solar water desalination (ISWD) systems. One design uses spray jets for spraying water onto the absorber plate, while the other uses a longitudinal slot for getting the inlet water on the absorber plate. The first ever ISWD system constructed and tested by Aybar et al (2005) used the longitudinal slot with a maximum daily production of 2.995 kg/m2 day. The Aybar et al design produced 3.4 kg/m2-day while the new design produced 6.41 kg/m2-day for wick on absorber plate system day during the hottest months in Famagusta (July-August 2010). Also tested was the influence of porous media (wire mesh), wick on the absorber plate. The effect of number of spray jets used in the system on the daily productivity and efficiency of the systems were also investigated.
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Dokonano oceny jakości wody do spożycia, dostarczanej przez wodociągi wiejskie gminy Węgorzewo położonej w województwie warmińsko-mazurskim. Ocena obejmuje lata 2009-2011. Przedmiotem badań objętych były 4 wodociągi w zakresie jakości wody, obejmujących następujące wybrane wskaźniki: barwę, mętność, odczyn, przewodność, jon amonowy, azotany(V), azotany(III), żelazo, mangan i bakteriologię. Do analizy zostały wykorzystane wyniki badań kontrolnych jakości wody prowadzone przez Stację Sanitarno-Epidemiologiczną. W celu poznania zmienności poszczególnych wskaźników, oprócz ich wartości średnich, obliczono także wartości maksymalne i minimalne, oraz liczbę przekroczeń dopuszczalnej wartości wskaźnika. Główny problem w grupie wskaźników fizyczno-chemicznych stanowią przekroczenia wartości mętności, żelaza, manganu i bakterii grupy coli oraz ogólnej grupy bakterii w 22°C.
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The physico-chemical quality of the potable water, provided by the waterworks of the selected poviat from Lesser Poland voivodeship, was evaluated. The objects of the research were 4 waterworks' and they were tested for the following water quality indexes: turbidity, reaction, conductivity, ammonia, nitrites, nitrates. The majority of problems in the group of physico-chemical indexes is caused by the transgressions of the water turbidity indexes.
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Collective water supply system (CWSS) belongs to the so called critical infrastructure with a priority importance for urban agglomerations. The draft of European standard Security of drinking water supply. Guidelines for risk and crisis management defines the concept of risk in CWSS and principles of management and protection in crisis situations. In the paper, a method for estimating the risk of failure in CWSS, based on the assumptions of classical matrix methods while information from the system operation is inaccurate, was proposed. The proposed method is based on fuzzy logic, which allows one to incorporate incomplete data and develop a risk evaluation system.
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The application of photocatalysis combined with membrane filtration for the oxidation of humic acid substances (HA) which is one of the major natural organic matters (NOMs) is discussed in this paper. Theoretical model shows a potential advantage of photo-catalytic filtration under low flux conditions. Cross-flow filtration is applied for HA removal using a TiO2 membrane under UV conditions. An increase of the flux through the membrane was observed by applying UV light.
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Water corrosion causes substantial damage to ductile, cast iron and steel water distribution systems. The corrosiveness of water depends on many physical, chemical, and even microbiological parameters. Stability indexes in respect of calcium carbonate like the Langelier Saturation Index (LSI) are also considered. First, the roles of inorganic complexes of calcium and manganese are discussed with respect to the accuracy of the calcium carbonate equilibrium calculations. As long as the drinking water parameters were below the EC Directive permissible values, neglecting these complexes had a small effect on the results of LSI computations. A model for computing LSI in water mixtures closed to the atmosphere was presented and partially verified on a small laboratory scale. Waters produced by all water treatment plants serving Kraków were evaluated in respect of the LSI, buffer capacity, and other parameters characterizing corrosive properties of water - in respect to iron. In general, the waters differed significantly in buffer capacity but all were evaluated as not presenting serious problems in internal corrosion of iron and cast iron, or more recently ductile iron pipes. This conclusion was verified based on a survey of main pipelines transporting water from the largest intake to the town, on the computations of the pipe roughness coefficient and on the mass balance of iron along the main transit pipes.
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The susceptibility of synthetic polymers to an overgrowth with microbial biofilm used in drinking water distribution system is assessed by calculating the number of microorganisms developing biofilms on specific materials and the analysis of the SEM images of biofilms.
PL
Oceniono podatność polimerów syntetycznych wykorzystywanych do dystrybucji wody do picia na obrosty mikrobiologiczne. Oceny dokonano, określając liczebność drobnoustrojów tworzących biofilmy na poszczególnych materiałach oraz analizując zdjęcia błon biologicznych ze skaningowego mikroskopu elektronowego.
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Adequate water quality is a priority goal to be met within the framework of the EU National Drinking Water Monitoring Program. As set forth in this program, the quality of water intended for human consumption is to be controlled by sanitary inspection units. Another important goal is to supply consumers with safe potable water and to take relevant actions to mini-mize the health hazard associated with water quality deterioration. According to WHO and the Regulation of the Ministry of Health, the recommended daily intake of manganese (0.5 mg ź dm-3) conforms to the public health protection strategy. In the present study, samples of raw and treated underground water from twelve intakes located in four mesoregions of northern Poland were analyzed during the years 1994-2004. Manganese concentrations were determined under the water quality moni-toring program, taking into account selected environmental and technological factors related to the condition of water supply networks. Manganese concentrations in raw water drawn from Tertiary, Quaternary and Cretaceous deposits ranged from 0.001 to 1.2 mg ź dm-3. Water quality was determined by the hydrogeological properties of deposits, and the highest manganese concen-trations were observed in raw water samples from the QT horizon in the region of Zulawy Water Mains. The average indicator of water treatment effectiveness reached 22 %. Despite the use of effective treatment methods, total manganese removal from water is impossible for technological reasons. The key factor affecting the manganese content of mains water is the concentration of this element in raw water. The study indicated that water is subject to secondary contamination during distri-bution, resulting from the condition and not type of the applied piping material. Therefore, it seems advisable to assess potential health risks to consumers posed by exceeding the maximum allowable concentrations (MAC) of manganese.
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Jakość wody do spożycia jest priorytetem w Narodowym Monitoringu Wody, który stworzony został w strukturach Unii Europejskiej, a realizowany przez inspekcje sanitarne. Ważnym celem użytecznym jest zapewnienie konsumentom wody o odpowiedniej jakości zdrowotnej oraz działanie w kierunku minimalizacji ryzyka zdrowotnego związanego z pogarszaniem jakości wody. Według WHO i Rozporządzenia Ministra Zdrowia zalecana wartość manganu 0,5 mg ź dm-3 jest odpowiednia dla ochrony zdrowia publicznego. W latach 1994-2004 wykonywano badania wód podziemnych surowych i uzdatnionych z dwunastu ujęć położonych w czterech mezoregionach północnej Polski. Analizie poddano mangan w ramach monitoringu kontrolnego, biorąc pod uwagę czynniki środowiskowe oraz związane z funkcjonowaniem sieci wodo. ciągowych. Wody surowe, ujmowane z utworów kredy, trzeciorzędu i czwartorzędu, reprezentowały stężenia w zakresie od 0,001 do 1,2 mg ź dm-3. Ich jakość uwarunkowana była cechami hydrogeologicznymi złoża, przy czym największe stężenia odnotowano w wodach ujmowanych ze wspólnego piętra QT w rejonie Centralnego Wodociągu Żuławskiego. Przeciętny wskaźnik efektywności uzdatniania wody wyniósł 22 %. Pomimo skutecznych metod uzdatniania, zupełna eliminacja tego składnika jest niemożliwa z powodów technologicznych systemu dystrybucji wody do konsumenta. Głównym czynnikiem kształtującym zawartość manganu w wodzie wodociągowej jest stężenie tego składnika w wodzie surowej. Badania wykazały wtórne zanieczyszczenie wód w sieci dystrybucyjnej, wynikające nie z zastosowanego rodzaju, lecz kondycji materiału budującego sieć. Dlatego celowa jest ocena ryzyka zdrowotnego konsumentów w razie przekroczeń wartości dopuszczalnych (NDS).
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