Worldwide, several regions suffer from water scarcity and contamination. The infiltration and subsurface storage of rain and river water can reduce water stress. Artificial groundwater recharge, possibly combined with bank filtration, plant purification and/or the use of subsurface dams and artificial aquifers, is especially advantageous in areas where layers of gravel and sand exist below the earth's surface. Artificial infiltration of surface water into the uppermost aquifer has qualitative and quantitative advantages. The contamination of infiltrated river water will be reduced by natural attenuation. Clay minerals, iron hydroxide and humic matter as well as microorganisms located in the subsurface have high decontamination capacities. By this, a final water treatment, if necessary, becomes much easier and cheaper. The quantitative effect concerns the seasonally changing river discharge that influences the possibility of water extraction for drinking water purposes. Such changes can be equalised by seasonally adapted infiltration/extraction of water in/out of the aquifer according to the river discharge and the water need. This method enables a continuous water supply over the whole year. Generally, artificially recharged groundwater is better protected against pollution than surface water, and the delimitation of water protection zones makes it even more save.
Filtration ; Fresh Water ; analysis ; Water Purification ; instrumentation ; methods ; Water Supply

The radioactive safety of drinking water has attracted increasing public concern. The newly issued Standards for Drinking Water Quality (GB5749-2022) in China has revised the radiological parameters. This article provides an overview of the main sources, levels of radionuclides in drinking water, and summarized the individual doses criterion and adverse health effects associated with exposure of the public to radionuclides from drinking-water. It analyzes and discusses the relevant revision content of radiological parameters, including the guidance values for screening gross α and gross β, subtracting the contribution of potassium-40 from gross β activity when the gross β activity concentration exceeds the screening level, and the basis for establishing the limit values of reference indices uranium and radium-226. Specific implementation and evaluation suggestions are also proposed.
Humans ; China ; Drinking Water ; Radioisotopes/analysis* ; Uranium/analysis* ; Water Supply

The present drinking water purification system in Egypt uses surface water as a raw water supply without a preliminary filtration process. On the other hand, chlorine gas is added as a disinfectant agent in two steps, pre- and post-chlorination. Due to these reasons most of water treatment plants suffer low filtering effectiveness and produce the trihalomethane (THM) species as a chlorination by-product. The Ismailia Canal represents the most distal downstream of the main Nile River. Thus its water contains all the proceeded pollutants discharged into the Nile. In addition, the downstream reaches of the canal act as an agricultural drain during the closing period of the High Dam gates in January and February every year. Moreover, the wide industrial zone along the upstream course of the canal enriches the canal water with high concentrations of heavy metals. The obtained results indicate that the canal gains up to 24.06x10(6) m3 of water from the surrounding shallow aquifer during the closing period of the High Dam gates, while during the rest of the year, the canal acts as an influent stream losing about 99.6x10(6) m3 of its water budget. The reduction of total organic carbon (TOC) and suspended particulate matters (SPMs) should be one of the central goals of any treatment plan to avoid the disinfectants by-products. The combination of sedimentation basins, gravel pre-filtration and slow sand filtration, and underground passage with microbiological oxidation-reduction and adsorption criteria showed good removal of parasites and bacteria and complete elimination of TOC, SPM and heavy metals. Moreover, it reduces the use of disinfectants chemicals and lowers the treatment costs. However, this purification system under the arid climate prevailing in Egypt should be tested and modified prior to application.
Egypt ; Industry ; Seasons ; Water Microbiology ; Water Movements ; Water Pollutants ; Water Purification ; methods ; Water Supply ; analysis

For drinking water security the German waterworks proceed on a comprehensive concept, i.e., the protection of all the regions from the recharge area to the client. It includes the protection of the recharge area by a precautionary management, a safe water treatment, a strict maintenance of the water distribution network, continuous control and an intensive training of staff. Groundwater protection zones together with effective regulations and control play a very important role. Three protection zones with different restrictions in land-use are distinguished. Water in reservoirs and lakes is also protected by Surface Water Protection Zones. Within the surrounding area the land-use is controlled, too. Special treatment is necessary if acidification happens caused by acid rain, or eutrophication caused by the inflow of sewage. Very important is the collaboration between waterworks and the farmers cultivating land in the recharge area in order to execute water-protecting ecological farming with the aim to reduce the application of fertilizers and plant protection agents. Probable financial losses have to be compensated by the waterworks.
Ecology ; Germany ; Water Pollutants ; isolation & purification ; Water Pollution ; prevention & control ; Water Purification ; methods ; Water Supply ; analysis

The revision of the national standards for drinking water quality is an important, rigorous and delicate endeavor. The paper introduced the revision of this standard, emphasizing the revision principle, overall technical considerations, and revision contents. Recommendations were also proposed for the implementation of this standard.
Humans ; Drinking Water ; Water Quality ; Reference Standards ; China ; Water Pollutants, Chemical/analysis* ; Water Supply

The establishment of limit values for standards of drinking water quality is an important and complex process. This study systematically introduced the methodology of the establishment of standard limit values for drinking water quality and elaborated on the workflow of setting limit values of water quality indicators, principles and methods of selecting water quality indicators, derivation of safety reference values, and establishment of limit values. It also aimed to provide reference and support for the future revision of relevant standards.
Humans ; Water Supply ; Drinking Water ; Reference Standards ; Water Quality ; Water Pollutants, Chemical/analysis*

BACKGROUND: Improved water sources are not equally available in all geographical regions. Populations dependent on unsafe water sources are recommended to treat their water at point-of-use using adequate methods to reduce associated health problems. In Ethiopia, the spatial distribution of households using unimproved water sources have been incomplete or ignored in most of the studies. Moreover, evidence on the point-of-use water treatment practice of households dependent on such water sources is scarce. Therefore, the current study is intended to analyze the spatial distribution of unimproved water sources by wealth quintiles at country level and point-of-use treatment (POU) practices using nationally representative data. METHOD: The data of 2016 Ethiopian Demographic and Health Survey (EDHS) conducted on 16650 households from 643 clusters were used for the analysis. For spatial analysis, the raw and spatially smoothed coverage data was joined to the geographic coordinates based on EDHS cluster identification code. Global spatial autocorrelation was performed to analyze whether the pattern of unimproved water coverage is clustered, dispersed, or random across the study areas. Once a positive global autocorrelation was confirmed, a local spatial autocorrelation analysis was applied to detect local clusters. The POU water treatment is analyzed based on reported use of either boiling, chlorine (bleach), filtration, or solar disinfection (SODIS). RESULTS: There were 5005 households using unimproved water sources for drinking purposes. Spatial variation of unimproved water coverage was observed with high coverage observed at Amhara, Afar, Southern Nations Nationalities and People and Somalia regions. Disparity in unimproved water coverage between wealth quintiles was also observed. The reported point-of-use water treatment practice among these households is only 6.24%. The odds of POU water treatment among household heads with higher education status is 2.5 times higher (95% CI = 1.43-4.36) compared to those who did not attend education. CONCLUSION An apparent clustering trend with high unimproved water coverage was observed between regions and among wealth quintiles hence indicates priority areas for future resource allocation and the need for regional and national policies to address the issue. Promoting households to treat water prior to drinking is essential to reduce health problems.
Drinking Water/analysis* ; Ethiopia ; Socioeconomic Factors ; Spatial Analysis ; Water Purification/methods* ; Water Supply/statistics & numerical data*

China ; Fluorine ; analysis ; toxicity ; Humans ; Neoplasms ; mortality ; Water Supply ; analysis

A study to determine the validity and predictive value of the hydrogen sulphide screening test for water quality compared to a standard multiple-tube technique test was undertaken. The hydrogen sulphide test was found to be highly sensitive and specific with a high predictive value. It is recommended as a screening test for water quality in developing countries where resources are limited. It will be especially useful in monitoring improvement in rural water supplies.
Evaluation Studies as Topic ; Hydrogen Sulfide ; Papua New Guinea ; Water Supply - analysis ; Water Supply - standards

OBJECTIVETo modify and optimize gas chromatographic conditions, qualitative and quantitative method on the base of the actual national standard detection method for drinking water on testing iodide with gas chromatography, and detect iodide in drinking water of Shanghai.

METHODSIodobutane derivative was identified by gas chromatography/mass spectrometry, then two capillary columns coupled to electron capture detector were made by qualitative and quantitative analysis. Finally, 100 ml water samples were collected respectively from raw water and finished water of three plants in which water sources were Yangtse river, Huangpu river, and inner river respectively and detected by this developed method.

RESULTSThe results of mass spectrometry showed that iodide would form iodobutane which could generate 1-iodo-2-butanone and 3-iodo-2-butanone isomers by derivatization. The data of qualitative analysis by two capillary columns revealed that iodobutane was separated completely and the total time of chromatogram separation was 19.33 min.3-iodo-2-butanone with the high response value was selected to quantitatively analyse. The linear range was 1 - 100 µg/L, and the coefficient of determination (r(2)) was 0.9997. The limit of detection was 13 ng/L. Recoveries were between 97.68% and 104.37%, and relative standard deviations were between 2.14% and 4.41%. The results of iodide detected by this method in raw water and finished water in three plants in Shanghai showed that the ranking of iodide's concentration in raw water was Huangpu river (15.14 µg/L) > inner river (6.97 µg/L) > Yangtse river (3.55 µg/L). The level of iodide in finished water of plant 1 (3.55 µg/L and 5.92 µg/L for raw and finished water respectively) and 3 (6.97 µg/L and 9.62 µg/L for raw and finished water respectively) increased slightly except for plant 2 (15.14 µg/L and 1.81 µg/L for raw and finished water respectively). The relative standard deviations of all water samples measured in duplicate were less than 9.73%.

CONCLUSIONThe improved method possesses higher degree of sensitivity and accuracy of qualitative and quantitative analysis than actual national standard detection method, and it is fit for trace analysis of iodide in water.