Based on the monitoring data of water quality of more than 40 centralized drinking water sources in 40 towns (townships or streets) of Kaixian County in the first and second half of each year during the "Twelfth Fi...Based on the monitoring data of water quality of more than 40 centralized drinking water sources in 40 towns (townships or streets) of Kaixian County in the first and second half of each year during the "Twelfth Five-year Plan" period, the changing rules of the water quality were studied to provide scientific references for the improvement of drinking water safety of urban and rural residents and drinking water quality. The re- sults show that the water quality of centralized drinking water sources in Kaixian County improved year by year during the "Twelfth Five-year Plan" period, and most monitoring sites with water quality exceeding the standard are distributed in reservoirs. Total phosphorus, total nitrogen, chemical oxygen demand, and permanganate index exceeded the standard obviously. Main pollution sources are domestic pollution and non-point source pol- lution caused by excessive discharge of nitrogen, phosphorus and organic pollutants. To improve drinking water quality, it is suggested that some towns can get drinking water from other reservoirs, surface water or underground water with better quality instead of previous reservoirs with water quality exceeding the standard, and the control of non-point source pollution should be enhanced.展开更多
Water quality is one of the main indicators of the quality of service provided to consumers. Quality has an impact on both the public health and aesthetic value of water as a consumable product. Kenya is classified as...Water quality is one of the main indicators of the quality of service provided to consumers. Quality has an impact on both the public health and aesthetic value of water as a consumable product. Kenya is classified as a water-scarce country with only 647 cubic meters of renewable freshwater per capita. Water distributed in Nairobi is faced with a myriad of challenges leading to a compromise to its quality. This study focused on evaluating quality of drinking water since human health depends on adequate, clean, reliable water. Analyses were carried out at National Environmental Management Authority (NEMA) accredited Jomo Kenyatta University of Agriculture and Technology (JKUAT) laboratories to determine the chemical, bacteriological and physical characteristics of consumed water in Umoja Innercore Estate in Nairobi. In the study area, 7 HH and 6 BH sites were randomly distributed. pH, turbidity and temperature measurements were analyzed in-situ while bacteria and chemicals were analyzed in laboratories. The study found that 100% of boreholes recorded unsatisfactory water with up to 1100 of Escherichia coli (E. coli) showing high contamination with faecal coliforms and 83% of boreholes recording pH of up to 9.53. Dissolved oxygen was 5.08 mg/L below recommended 12.0 mg/L, salinity of 0.47 mg/L and 0.03 mg/L for boreholes and households respectively. The study reveals the deprived quality of water available to the residents of Umoja Innercore, Nairobi. The study recommends the use of biosand filtration methods for septic tanks, digging of deeper boreholes and lining septic tanks with impermeable materials to prevent contamination of ground water with raw water from septic.展开更多
The World Bank estimates that 21% of all communicable diseases in India are related to unsafe water with diarrhoea alone causing more than 0.1 million deaths annually. The WHO drinking water surveillance parameters of...The World Bank estimates that 21% of all communicable diseases in India are related to unsafe water with diarrhoea alone causing more than 0.1 million deaths annually. The WHO drinking water surveillance parameters of quality, quantity, accessibility, affordability and continuity were assessed in one vulnerable ward of Ahmedabad—a fast growing city in Western India. Interviews with key informants of the ward office, health centre and water supply department, secondary analysis and mapping of field test reports and a questionnaire-based survey of different household types were conducted. We found that Ahmedabad Municipal Corporation (AMC) supplies water to the ward intermittently for two hours during the day. Housing society clusters supplement their AMC water supply with untested bore-well water. The water quality surveillance system is designed for a twenty-four-hour piped distribution of treated surface water. However, in order to maintain surveillance over an intermittent supply that includes ground water, the sampling process should include periodic surveys of water actually consumed by the citizens. The laboratory capacity of the Central Water Testing Laboratory should expand to include more refined tests for microbial and chemical contamination.展开更多
The United States Environmental Protection Agency (EPA) has the authority to regulate the public water systems. The EPA does not have the jurisdiction to regulate private drinking water wells. This leaves approximatel...The United States Environmental Protection Agency (EPA) has the authority to regulate the public water systems. The EPA does not have the jurisdiction to regulate private drinking water wells. This leaves approximately fifteen percent of the nation’s population without any regulation being held in place to protect their source of drinking water. With that fifteen percent of the US population having private wells for drinking water, it makes the number of people whose drinking water is unprotected by regulation at a little over 15 million US households. This concern is even more acute in areas with groundwater that is close to the surface. Delaware residents live in a region with low elevation which is very close to the coast with low elevation and the shallow groundwater makes us concern about contaminated well water even more intense. As one of the Water Resources Program partners, we have offered free Drinking Water Quality Clinics to local well owners over the past 4 years in Delaware State University. Since 2009, over 400 Delaware residents have benefited from these clinics. At each clinic, an information session was offered in the evening, with an opportunity to hear from and speak with a drinking water well expert. Participants were given sample bottles and water testing performed the following day included pH, nitrite, nitrate, sulfate, alkalinity, fluoride, hardness, iron, lead, cadmium, arsenic, Total Coliform, and E. coli. Over half of the samples returned out of range values for pH, while 72 returned results positive for Total Coliform and Escherichia coli bacterium. Data are examined for correlations, and improved understanding of local well owners. These tests shared with local well owners insights into what may be wrong with their water. In addition, any tests that came back outside of the normal range were reported to homeowners in writing. Mailed with the written reports were also information specific to what test results were outside of the limits, and actions to take to correct the exact problem the well owners encountered. The data reported here are examined to discuss the correlations of information, and ways that the Drinking Water Quality Clinics have improved our understanding of local wells and ownerships. In conclusion, regular testing on a yearly basis is the most effective way to ensure that public health is maintained.展开更多
Riparian land use/land cover(LULC)plays a crucial role in maintaining riverine water quality by altering the transport of pollutants and nutrients.Nevertheless,establishing a direct relationship between water quality ...Riparian land use/land cover(LULC)plays a crucial role in maintaining riverine water quality by altering the transport of pollutants and nutrients.Nevertheless,establishing a direct relationship between water quality and LULC is challenging due to the multi-indicator nature of both factors.Water quality encompasses a multitude of physical,chemical,and biological parameters,while LULC represents a diverse array of land use types.Riparian habitat quality(RHQ)serves as an indicator of LULC.Yet,it remains to be seen whether RHQ can act as a proxy of LULC for assessing the impact of LULC on riverine water quality.This study examines the interplay between RHQ,LULC and water quality,and develops a comprehensive indicator to predict water quality.We measured several water quality parameters,including pH(potential of hydrogen),TN(total nitrogen),TP(total phosphorus),T_(water)(water temperature),DO(dissolved oxygen),and EC(electrical conductivity)of the Yue and Jinshui Rivers draining to the Han River during 2016,2017 and 2018.The water quality index(WQI)was further calculated.RHQ is assessed by the InVEST(Integrated Valuation of Ecosystem Services and Tradeoffs)model.Our study found noticeable seasonal differences in water quality,with a higher WQI observed in the dry season.The RHQ was strongly correlated with LULC compositions.RHQ positively correlated with WQI,and DO concentration and vegetation land were negatively correlated with T_(water),TN,TP,EC,cropland,and construction land.These correlations were stronger in the rainy season.Human-dominated land,such as construction land and cropland,significantly contributed to water quality degradation,whereas vegetation promoted water quality.Regression models showed that the RHQ explained variations in WQI better than LULC types.Our study concludes that RHQ is a new and comprehensive indicator for predicting the dynamics of riverine water quality.展开更多
Secondary water supply systems(SWSSs)are important components of the water supply infrastructure that ensure residents’drinking water safety.SWSSs are characterized by long detention time,warm temperature,and unreaso...Secondary water supply systems(SWSSs)are important components of the water supply infrastructure that ensure residents’drinking water safety.SWSSs are characterized by long detention time,warm temperature,and unreasonable management,which may trigger the deterioration of water quality and increase risks.In this study,drinking water quality index(DWQI)and health risk assessment(HRA)were selected and modified to quantitatively assess the water quality and health risks of SWSSs in residential neighborhoods.In total,121 seasonal water samples were selected.It was observed that the water quality was excellent with the DWQI of 0.14±0.04,excluding one sample,which was extremely poor owing to its excessive total bacterial count.The HRA results revealed that the health risks were low:negligible non-carcinogenic risk for any population;negligible and acceptable carcinogenic risk for children aged 6–17 and adults.However,samples revealed higher carcinogenic risk(7.63×10−5±3.29×10−6)for children aged 0–5,and arsenic was the major substance.Summer samples had poor water quality and higher health risks,which called for attention.To further investigate the water quality and health risks of SWSSs,monthly sampling was conducted during summer.All 24 water samples were qualified in Chinese standard(GB 5749-2022)and characterized as excellent quality.Their HRA results were consistent with the seasonal samples’and the health risks were mainly concentrated in May.Overall,our study provides a suitable framework for water quality security,advice for managers,and references for administrators in other cities.展开更多
To develop a better approach for spatial evaluation of drinking water quality, an intelligent evaluation method integrating a geographical information system(GIS) and an ant colony clustering algorithm(ACCA) was used....To develop a better approach for spatial evaluation of drinking water quality, an intelligent evaluation method integrating a geographical information system(GIS) and an ant colony clustering algorithm(ACCA) was used. Drinking water samples from 29 wells in Zhenping County, China, were collected and analyzed. 35 parameters on water quality were selected, such as chloride concentration, sulphate concentration, total hardness, nitrate concentration, fluoride concentration, turbidity, pH, chromium concentration, COD, bacterium amount, total coliforms and color. The best spatial interpolation methods for the 35 parameters were found and selected from all types of interpolation methods in GIS environment according to the minimum cross-validation errors. The ACCA was improved through three strategies, namely mixed distance function, average similitude degree and probability conversion functions. Then, the ACCA was carried out to obtain different water quality grades in the GIS environment. In the end, the result from the ACCA was compared with those from the competitive Hopfield neural network(CHNN) to validate the feasibility and effectiveness of the ACCA according to three evaluation indexes, which are stochastic sampling method, pixel amount and convergence speed. It is shown that the spatial water quality grades obtained from the ACCA were more effective, accurate and intelligent than those obtained from the CHNN.展开更多
Monitoring water quality is important for maintaining a healthy watershed, but it is mostly ignored in watershed planning and management. In the Dhrabi watershed of Pakistan, the quality of surface water was monitored...Monitoring water quality is important for maintaining a healthy watershed, but it is mostly ignored in watershed planning and management. In the Dhrabi watershed of Pakistan, the quality of surface water was monitored at 16 locations to assess suitability for irrigation over regular intervals during the period 2007-2010. Similarly, groundwater quality was monitored at 10 locations for drinking and irrigation purposes. There was high spatial and temporal variability in surface water quality. Electrical conductivity (EC) and residual sodium carbonate (RSC) either exceeded or fluctuated around permissible limits at most of the locations throughout the monitoring period. Therefore, the use of such water for irrigation needs special care, otherwise its prolonged use may pose soil salinity and sodicity problems. The trend of EC and RSC for groundwater was similar to that for surface water. Exchangeable Mg2+ exceeded permissible limits for most of the surface water and groundwater samples. In addition, microbial analysis of groundwater revealed that only two out of eight monitoring points during August 2009, none out of eight points during February 2010, and one out of nine points during June 2010 provided water fit for drinking. Soil samples were collected from the catchment areas of the major contributing streams and from the beds of the Kallar Kahar Lake and the Dhrabi Reservoir. The soil samples from the catchments showed high salinity and sodicity that may be the cause of high salinity and sodicity in the streams. The highest EC, sodium adsorption ratio (SAP,) and exchangeable sodium percentage (ESP) in the bed samples from the Kallar Kahar Lake were about 43 dS/m, 56, and 45, respectively. These high values were due to the saline water brought into the lake with the runoff.展开更多
Tank cascade system(TCS)is a series of tanks located in a meso-catchment and has been accepted as a Globally Important Agricultural Heritage System found in Sri Lanka.Ecosystem components of the TCS play a major role ...Tank cascade system(TCS)is a series of tanks located in a meso-catchment and has been accepted as a Globally Important Agricultural Heritage System found in Sri Lanka.Ecosystem components of the TCS play a major role in purifying water within the system.This study attempted to investigate the water quality status and the farmers’willingness to rehabilitate the ecosystem components of the Thirappane TCS.Drinking and irrigation water quality parameters were tested in 34 locations and drinking and irrigation water quality indexes were calculated.Participatory rural appraisal and a questioner survey were conducted to gather social data.Water of TCS was observed to be appropriate for irrigation but not for drinking during the Maha cropping season.Based on the results of the Nitrate(as NO_(3)^(-))and Total Phosphate(as PO_(4)^(3-)),water of TCS can be categorized as eutrophic.Presence of ecosystem features of tank cascade system,annual income of the respondents,satisfaction on the quality of water for drinking,and the awareness about the tank cascade system significantly influenced the participatory decisions of the community on the rehabilitation of TCS.This study shall be an example and an eye opener to formulate sustainable tank cascade management plan.展开更多
To study arsenic (As) content and distribution patterns as well as the genesis of different kinds of water,especially the different sources of drinking water in Guanzhong Basin,Shaanxi province,China,139 water sampl...To study arsenic (As) content and distribution patterns as well as the genesis of different kinds of water,especially the different sources of drinking water in Guanzhong Basin,Shaanxi province,China,139 water samples were collected at 62 sampling points from wells of different depths,from hot springs,and rivers.The As content of these samples was measured by the intermittent flowhydride generation atomic fluorescence spectrometry method (HG-AFS).The As concentrations in the drinking water in Guanzhong Basin vary greatly (0.00-68.08 tg/L),and the As concentration of groundwater in southern Guanzhong Basin is different from that in the northern Guanzhong Basin.Even within the same location in southern Guanzhong Basin,the As concentrations at different depths vary greatly.As concentration of groundwater from the shallow wells (〈50 m deep,0.56-3.87 μg/L) is much lower than from deep wells (110-360 m deep,19.34-62.91 μg/L),whereas As concentration in water of any depth in northern Guanzhong Basin is 〈10 μg/L.Southern Guanzhong Basin is a newly discovered high-As groundwater area in China.The high-As groundwater is mainly distributed in areas between the Qinling Mountains and Weihe River; it has only been found at depths ranging from 110 to 360 m in confined aquifers,which store water in the Lishi and Wucheng Loess (Lower and Middle Pleistocene) in the southern Guanzhong Basin.As concentration of hot spring water is 6.47-11.94 μg/L; that of geothermal water between 1000 and 1500 m deep is 43.68-68.08 μg/L.The high-As well water at depths from 110 to 360 m in southern Guanzhong Basin has a very low fluorine (F) value,which is generally 〈0.10 mg/L.Otherwise,the hot springs of Lintong and Tangyu and the geothermal water in southern Guanzhong Basin have very high F values (8.07-14.96 mg/L).The results indicate that high As groundwater in depths from 110 to 360 m is unlikely to have a direct relationship with the geothermal water in the same area.As concentration of all reservoirs and rivers (both contaminated and uncontaminated) in the Guanzhong Basin is 〈10 μg/L.This shows that pollution in the surface water is not the source of the high-As in the southern Guanzhong Basin.The partition boundaries of the high-and low-As groundwater area corresponds to the partition boundaries of the tectonic units in the Guanzhong Basin.This probably indicates that the high-As groundwater areas can be correlated to their geological underpinning and structural framework.In southern Guanzhong Basin,the main sources of drinking water for villages and small towns today are wells between 110-360 m deep.All of their As contents exceed the limit of the Chinese National Standard and the International Standard (〉10 μg/L) and so local residents should use other sources of clean water that are 〈50 m deep,instead of deep groundwater (110 to 360 m) for their drinking water supply.展开更多
Backgrounds: One of the fundamental needs of a community is to have an access to healthy and safe drinking water. The lack of a concentrated accessibility to health facilities and services is among the serious problem...Backgrounds: One of the fundamental needs of a community is to have an access to healthy and safe drinking water. The lack of a concentrated accessibility to health facilities and services is among the serious problems facing villagers in the rural areas. The aims of this research was to investigate the drinking water quality of the villages in Babol township suburbs in north of Iran. Materials and Methods: In this cross-sectional descriptive study, a total of 140 water samples were taken from the water distribution network in16 villages for the low and high-rain seasons in sterile glass bottle. The microbial quality of gathered samples were determined based on standard methods in laboratory. Statistical analysis of the results was performed using a SPSS16 statistical software. Findings: Based on obtained results 13.6% of the samples were contaminated to coliform and 20% to fecal coliform bacteria. The residual chlorine in 12.5% of the samples were between 0.2 to 0.8 mg·L-1 and the PH in total samples were between 6.8 to 7.8. There were no signs of any contamination for 32.86% of the analysed samples which water resources is located to a distance of more than 30 m to the contamination sources. In addition, 43.1% of the samples taken from the water resources with no plumbing system, have had a fecal contamination. Conclusions: Considering the results achieved, the microbial quality of the drinking water of the studied villages classified as “moderate” status. For more water supply there is not sufficient residual chlorine in most cases. Poor sanitation of water supply is most causes of water contamination. It is therefore strongly recommended that sanitation measures are made to protect water resources from the contamination.展开更多
Minerals and constitutes in drinking water are vital for the nutrition of human bodies. Certain limits of water quality parameters must be met to ensure the safety of bottled drinking water for the human consumption. ...Minerals and constitutes in drinking water are vital for the nutrition of human bodies. Certain limits of water quality parameters must be met to ensure the safety of bottled drinking water for the human consumption. Thirty two local and twelve imported brands of bottled water in Saudi Arabia have been collected to verify their compliance with international and local standards which are EPA (2016), WHO (2013) and SASO (2009). A proposed scoring system is used to evaluate the water quality. Fayha and Hilwa brands have been selected as the best local brands whereas Volvic brand as the optimal imported brand in the western region of Saudi Arabia. The local water brands are more reliable to the standards than the imported brands. Licensed water brands in Saudi Arabia are found to have a good water quality which satisfied the quality requirements.展开更多
Water is an essential element on earth,which provides human a variety of services in domestic use,agriculture,or industries.However,some serious health risks of drinking water are associated with microbial contaminati...Water is an essential element on earth,which provides human a variety of services in domestic use,agriculture,or industries.However,some serious health risks of drinking water are associated with microbial contamination,particularly with fecal matter.Therefore,microbial quality assessment is considered to be a necessary component of water quality assessment.This study investigates microbial contamination of water distributary system around the city by comparing groundwater(GW)and tap water(TW)quality in Quetta city.31 GW samples and 31 TW samples were collected in the study area during the months of September,October,and November.Fecal coliform test was carried out in laboratory and their average total coliform contamination was computed.Results showed that the TW sample were all contaminated by coliform except for Chiltan town,hence are not considered suitable for drinking without any treatment according to WHO drinking water quality standards.The average coliform concentrations were 12 in Quetta main city,11.6 in Jinnah town,5.3 in Satallite town,10 in Shahbaz town and 5 in Brewery town(0/100 mL CFU)and the TW samples from the three towns were even more contaminated with E.coli.Whereas among the GW,average microbial concentrations were 1.8 in Quetta main city,2 in Satallite town,1.4 in Shahbaz town,and 0.4 in Chiltan town(0/100 mL CFU),respectively,which shows that the contamination is occurring within the water distributary pipeline system when the water flows through the pipelines.Moreover,this research will be valuable for researchers and administrative authorities to conduct elaborative studies,and develop new policies to prevent further deterioration of drinking water in the water distribution system by pathogenic microorganisms and ensure safe drinking water to the public of Quetta city.展开更多
To investigate the water quality of sampling in aquaculture ponds around the basic farmland protection areas in the five districts of Foshan city, and use the environmental pollution index to evaluate the condition of...To investigate the water quality of sampling in aquaculture ponds around the basic farmland protection areas in the five districts of Foshan city, and use the environmental pollution index to evaluate the condition of water quality. The results indicated that water temperature and pH of aquaculture ponds cound meet the requirements of fish normal growth,and dissolved oxygen was rich, but the water quality was over fertilized generally. In 20 investigation spots of the five districts, the content of CODCr, NH4^+-N and TP exceeded 90%, 30% and 85% respectively. The pollution degrees of the water quality from high to low in aquaculture ponds were Chancheng district,Nanhai district, Sanshui district, Shunde district, Gaoming district. The comprehensive quality index of aquaculture ponds was 1.44 in Foshan city, the water quality was polluted severly as a whole. The share rate of pollution load of TP was the highest, the second were CODCr and NH4^+-N. On the whole, the pollution of organic matter was very prominent in the water quality of aquaculture ponds around the basic farmland protection areas in Foshan city that had been eutrophicated.展开更多
The present study aims at measuring the activity concentrations of ^210Po and ^210Pb in the potable water of Eloor, a major industrial belt in the Ernakulam district of Kerala, India with an aim of evaluating resultan...The present study aims at measuring the activity concentrations of ^210Po and ^210Pb in the potable water of Eloor, a major industrial belt in the Ernakulam district of Kerala, India with an aim of evaluating resultant ingestion dose to critical population. The industrial units located in Eloor discharge their treated effluents into the river Periyar and the surrounding environs. The two major industries of interest with respect to NORMs are the fertilizer plant, processing rock phosphate and the monazite processing plant, which had been in operation for the last 50 years. For sampling, Eloor region was divided into four zones and a total of 55 water samples from different locations were collected and analysed as per standard analytical procedure manual of BARC. The ^210Po concentration ranged between 0.3 to 4.7 mBq.L^-1 and ^210Pb ranged from 0.6 to 4.3 mBq.L^-1. All values are well below the limit of 0.1 Bq.Ll recommended by World Health Organization. Statistical analysis shows a good co-relation between ^210Po and ^210Pb in the water samples analyzed and the mean activity concentration is found to be relatively high in the western region of Eloor compared to other regions. The annual effective dose equivalent to man from ^210Po and ^210Pb through drinking water intake were estimated and found to be 1.13 μSv.y^-1 and 0.99 μSv.y^-1 respectively, which is well below the reference level of committed effective dose (100 μSv.y^-1) recommended by WHO.展开更多
The Yangtze River flows through Jiangsu Province, bringing abundant water resources to people in this province. However, environmental pollution and destruction of vegetation in recent years have led to deterioration ...The Yangtze River flows through Jiangsu Province, bringing abundant water resources to people in this province. However, environmental pollution and destruction of vegetation in recent years have led to deterioration of water quality of the Yangtze, bringing about many bad effects on people’s life and production. Through a comprehensive analysis of water quality of the Yangtze River through Jiangsu Province, we investigated the reasons for the deterioration of its water quality, and explored countermeasure to maintain good water quality in the Yangtze with the objective to provide safe and reliable drinking water sources for people.展开更多
Clean drinking water is one of the United Nations Sustainable Development Goals.Despite significant progress in the water purification technology,many regions still lack access to clean water.This paper provides a rev...Clean drinking water is one of the United Nations Sustainable Development Goals.Despite significant progress in the water purification technology,many regions still lack access to clean water.This paper provides a review of selected water contaminants and their impacts on human health.The World Health Organization(WHO)guidelines and regional standards for key contaminants were used to characterise water quality in the European Union and UK.The concept of safe drinking water was explained based on the non-observed adverse effect level,threshold concentrations for toxic chemicals,and their total daily intake.Various techniques for monitoring water contaminants and the drinking water standards from five different countries,including the UK,USA,Canada,Pakistan and India,were compared to WHO recommended guidelines.The literature on actual water quality in these regions and its potential health impacts was also discussed.Finally,the role of public water suppliers in identifying and monitoring drinking water contaminants in selected developed countries was presented as a potential guideline for developing countries.This review emphasised the need for a comprehensive understanding of water quality and its impacts on human health to ensure access to clean drinking water worldwide.展开更多
The continuously deteriorating quality of source water is threatening the safety of drinking water in China.Various efforts have been made to update water treatment processes to decrease the pollution problems of drin...The continuously deteriorating quality of source water is threatening the safety of drinking water in China.Various efforts have been made to update water treatment processes to decrease the pollution problems of drinking water,such as protection of drinking water sources,enhance-ment of conventional treatment processes,and development of new or advanced treatment technologies.This paper reviews a variety of protection and remediation methods for drinking water sources,development and application of drinking water treatment technologies,new technologies for special pollutants removal from groundwater,and the latest research progress on water distribution systems in China.展开更多
The present study assesses the physicochemical and bacteriological quality of the drinking water used by the population of S?-Ava based on the Beninese standards and those established by the World Health Organization ...The present study assesses the physicochemical and bacteriological quality of the drinking water used by the population of S?-Ava based on the Beninese standards and those established by the World Health Organization (WHO). In rural and peri-urban areas of Benin where public water supply systems are inadequate or almost non-existent, the population consumes water of various sources of unknown qualities. A total of 67 water samples were analyzed during the rainy season (July 2017) and in the dry season (January 2018) for certain physical, chemical and bacteriological parameters using the standard methods. The results of the analyses reveal that the physicochemical characteristics of the water used for consumption in S?-Ava comply with the drinking water standards of the World Health Organization and those in force in Benin except for the percentages of the following parameters: pH (41.80%);turbidity (25.37%);the color (16.42);ammonium (17.91%);iron (40.30%);Nitrites (4.48%);Residual chlorine (91.05). Bacteriologically, the analyses showed a high total aerobic mesophilic flora contamination, faecal coliforms, E. coli, faecal enterococci respectively in 89.55%, 82.09%, 50.75% and 70.15% of the analyzed water samples. The ratio of faecal coliforms to faecal enterococci indicated that the origin of faecal contamination was human in 59.7% of the samples and animal in 40.3% of the samples. The adoption of hygiene measures at the water point, during the transport and storage of water, including the treatment by chlorination of drinking water at the family level was recommended for the population concerned and household awareness on the adoption of basic hygiene and sanitation measures have been recommended for hygiene and sanitation services.展开更多
Sustaining a reliable and contaminant-free drinking water is becoming an increasing challenge worldwide due to human activity, industrial waste, and agricultural overuse. Surface water is the main source of drinking w...Sustaining a reliable and contaminant-free drinking water is becoming an increasing challenge worldwide due to human activity, industrial waste, and agricultural overuse. Surface water is the main source of drinking water around the world. However, groundwater is also becoming increasingly popular, due to its clarity and minimal need for processing to reduce turbidity. Over the years, the demand and growth in the agricultural industry has also been the means of groundwater contamination. Due to the health burden that raw water can pose, water must be processed and purified prior to consumption. Raw water quality can be compromised by physical, chemical (heavy metals and disinfection by-products), and biological contaminants. Biological contaminants can significantly impact immunocompromised populations, while chemical contaminants can impact the growth and development of young children. Although obtaining a steady and high-quality water flow to the general population is an increasing challenge, developed countries have utilized state-of-the-art technologies and techniques to provide contaminant-free water to their citizens. This research aims to provide information about the regulatory parameters, characteristics, and sources of safe drinking water in the world as a model for future use in the developing world. In this, secondary data was used to compare and contrast drinking water quality among countries in the European Union, the United States, Canada, the United Kingdom, Singapore, New Zealand, Australia, Qatar, and the United Arab Emirates. The data indicates that Ireland and the United Kingdom have relatively lower amounts of contaminants in their drinking water. Upon completing this research, it is recommended that countries desiring clean drinking water systems should initiate and invest in programs that control and protect treatment plants, water distribution systems, water sources, and catchments.展开更多
文摘Based on the monitoring data of water quality of more than 40 centralized drinking water sources in 40 towns (townships or streets) of Kaixian County in the first and second half of each year during the "Twelfth Five-year Plan" period, the changing rules of the water quality were studied to provide scientific references for the improvement of drinking water safety of urban and rural residents and drinking water quality. The re- sults show that the water quality of centralized drinking water sources in Kaixian County improved year by year during the "Twelfth Five-year Plan" period, and most monitoring sites with water quality exceeding the standard are distributed in reservoirs. Total phosphorus, total nitrogen, chemical oxygen demand, and permanganate index exceeded the standard obviously. Main pollution sources are domestic pollution and non-point source pol- lution caused by excessive discharge of nitrogen, phosphorus and organic pollutants. To improve drinking water quality, it is suggested that some towns can get drinking water from other reservoirs, surface water or underground water with better quality instead of previous reservoirs with water quality exceeding the standard, and the control of non-point source pollution should be enhanced.
文摘Water quality is one of the main indicators of the quality of service provided to consumers. Quality has an impact on both the public health and aesthetic value of water as a consumable product. Kenya is classified as a water-scarce country with only 647 cubic meters of renewable freshwater per capita. Water distributed in Nairobi is faced with a myriad of challenges leading to a compromise to its quality. This study focused on evaluating quality of drinking water since human health depends on adequate, clean, reliable water. Analyses were carried out at National Environmental Management Authority (NEMA) accredited Jomo Kenyatta University of Agriculture and Technology (JKUAT) laboratories to determine the chemical, bacteriological and physical characteristics of consumed water in Umoja Innercore Estate in Nairobi. In the study area, 7 HH and 6 BH sites were randomly distributed. pH, turbidity and temperature measurements were analyzed in-situ while bacteria and chemicals were analyzed in laboratories. The study found that 100% of boreholes recorded unsatisfactory water with up to 1100 of Escherichia coli (E. coli) showing high contamination with faecal coliforms and 83% of boreholes recording pH of up to 9.53. Dissolved oxygen was 5.08 mg/L below recommended 12.0 mg/L, salinity of 0.47 mg/L and 0.03 mg/L for boreholes and households respectively. The study reveals the deprived quality of water available to the residents of Umoja Innercore, Nairobi. The study recommends the use of biosand filtration methods for septic tanks, digging of deeper boreholes and lining septic tanks with impermeable materials to prevent contamination of ground water with raw water from septic.
文摘The World Bank estimates that 21% of all communicable diseases in India are related to unsafe water with diarrhoea alone causing more than 0.1 million deaths annually. The WHO drinking water surveillance parameters of quality, quantity, accessibility, affordability and continuity were assessed in one vulnerable ward of Ahmedabad—a fast growing city in Western India. Interviews with key informants of the ward office, health centre and water supply department, secondary analysis and mapping of field test reports and a questionnaire-based survey of different household types were conducted. We found that Ahmedabad Municipal Corporation (AMC) supplies water to the ward intermittently for two hours during the day. Housing society clusters supplement their AMC water supply with untested bore-well water. The water quality surveillance system is designed for a twenty-four-hour piped distribution of treated surface water. However, in order to maintain surveillance over an intermittent supply that includes ground water, the sampling process should include periodic surveys of water actually consumed by the citizens. The laboratory capacity of the Central Water Testing Laboratory should expand to include more refined tests for microbial and chemical contamination.
文摘The United States Environmental Protection Agency (EPA) has the authority to regulate the public water systems. The EPA does not have the jurisdiction to regulate private drinking water wells. This leaves approximately fifteen percent of the nation’s population without any regulation being held in place to protect their source of drinking water. With that fifteen percent of the US population having private wells for drinking water, it makes the number of people whose drinking water is unprotected by regulation at a little over 15 million US households. This concern is even more acute in areas with groundwater that is close to the surface. Delaware residents live in a region with low elevation which is very close to the coast with low elevation and the shallow groundwater makes us concern about contaminated well water even more intense. As one of the Water Resources Program partners, we have offered free Drinking Water Quality Clinics to local well owners over the past 4 years in Delaware State University. Since 2009, over 400 Delaware residents have benefited from these clinics. At each clinic, an information session was offered in the evening, with an opportunity to hear from and speak with a drinking water well expert. Participants were given sample bottles and water testing performed the following day included pH, nitrite, nitrate, sulfate, alkalinity, fluoride, hardness, iron, lead, cadmium, arsenic, Total Coliform, and E. coli. Over half of the samples returned out of range values for pH, while 72 returned results positive for Total Coliform and Escherichia coli bacterium. Data are examined for correlations, and improved understanding of local well owners. These tests shared with local well owners insights into what may be wrong with their water. In addition, any tests that came back outside of the normal range were reported to homeowners in writing. Mailed with the written reports were also information specific to what test results were outside of the limits, and actions to take to correct the exact problem the well owners encountered. The data reported here are examined to discuss the correlations of information, and ways that the Drinking Water Quality Clinics have improved our understanding of local wells and ownerships. In conclusion, regular testing on a yearly basis is the most effective way to ensure that public health is maintained.
基金supported by the National Natural Science Foundation of China(Grant No.31670473)the Wuhan Institute of Technology funding to Dr.Siyue Li(Grant No.21QD02).
文摘Riparian land use/land cover(LULC)plays a crucial role in maintaining riverine water quality by altering the transport of pollutants and nutrients.Nevertheless,establishing a direct relationship between water quality and LULC is challenging due to the multi-indicator nature of both factors.Water quality encompasses a multitude of physical,chemical,and biological parameters,while LULC represents a diverse array of land use types.Riparian habitat quality(RHQ)serves as an indicator of LULC.Yet,it remains to be seen whether RHQ can act as a proxy of LULC for assessing the impact of LULC on riverine water quality.This study examines the interplay between RHQ,LULC and water quality,and develops a comprehensive indicator to predict water quality.We measured several water quality parameters,including pH(potential of hydrogen),TN(total nitrogen),TP(total phosphorus),T_(water)(water temperature),DO(dissolved oxygen),and EC(electrical conductivity)of the Yue and Jinshui Rivers draining to the Han River during 2016,2017 and 2018.The water quality index(WQI)was further calculated.RHQ is assessed by the InVEST(Integrated Valuation of Ecosystem Services and Tradeoffs)model.Our study found noticeable seasonal differences in water quality,with a higher WQI observed in the dry season.The RHQ was strongly correlated with LULC compositions.RHQ positively correlated with WQI,and DO concentration and vegetation land were negatively correlated with T_(water),TN,TP,EC,cropland,and construction land.These correlations were stronger in the rainy season.Human-dominated land,such as construction land and cropland,significantly contributed to water quality degradation,whereas vegetation promoted water quality.Regression models showed that the RHQ explained variations in WQI better than LULC types.Our study concludes that RHQ is a new and comprehensive indicator for predicting the dynamics of riverine water quality.
基金supported by the National Natural Science Foundation of China(No.U2005206)the Xiamen Municipal Bureau of Science and Technology(China)(No.YDZX20203502000003).
文摘Secondary water supply systems(SWSSs)are important components of the water supply infrastructure that ensure residents’drinking water safety.SWSSs are characterized by long detention time,warm temperature,and unreasonable management,which may trigger the deterioration of water quality and increase risks.In this study,drinking water quality index(DWQI)and health risk assessment(HRA)were selected and modified to quantitatively assess the water quality and health risks of SWSSs in residential neighborhoods.In total,121 seasonal water samples were selected.It was observed that the water quality was excellent with the DWQI of 0.14±0.04,excluding one sample,which was extremely poor owing to its excessive total bacterial count.The HRA results revealed that the health risks were low:negligible non-carcinogenic risk for any population;negligible and acceptable carcinogenic risk for children aged 6–17 and adults.However,samples revealed higher carcinogenic risk(7.63×10−5±3.29×10−6)for children aged 0–5,and arsenic was the major substance.Summer samples had poor water quality and higher health risks,which called for attention.To further investigate the water quality and health risks of SWSSs,monthly sampling was conducted during summer.All 24 water samples were qualified in Chinese standard(GB 5749-2022)and characterized as excellent quality.Their HRA results were consistent with the seasonal samples’and the health risks were mainly concentrated in May.Overall,our study provides a suitable framework for water quality security,advice for managers,and references for administrators in other cities.
基金Projects(41161020,41261026) supported by the National Natural Science Foundation of ChinaProject(BQD2012013) supported by the Research starting Funds for Imported Talents,Ningxia University,China+1 种基金Project(ZR1209) supported by the Natural Science Funds,Ningxia University,ChinaProject(NGY2013005) supported by the Key Science Project of Colleges and Universities in Ningxia,China
文摘To develop a better approach for spatial evaluation of drinking water quality, an intelligent evaluation method integrating a geographical information system(GIS) and an ant colony clustering algorithm(ACCA) was used. Drinking water samples from 29 wells in Zhenping County, China, were collected and analyzed. 35 parameters on water quality were selected, such as chloride concentration, sulphate concentration, total hardness, nitrate concentration, fluoride concentration, turbidity, pH, chromium concentration, COD, bacterium amount, total coliforms and color. The best spatial interpolation methods for the 35 parameters were found and selected from all types of interpolation methods in GIS environment according to the minimum cross-validation errors. The ACCA was improved through three strategies, namely mixed distance function, average similitude degree and probability conversion functions. Then, the ACCA was carried out to obtain different water quality grades in the GIS environment. In the end, the result from the ACCA was compared with those from the competitive Hopfield neural network(CHNN) to validate the feasibility and effectiveness of the ACCA according to three evaluation indexes, which are stochastic sampling method, pixel amount and convergence speed. It is shown that the spatial water quality grades obtained from the ACCA were more effective, accurate and intelligent than those obtained from the CHNN.
文摘Monitoring water quality is important for maintaining a healthy watershed, but it is mostly ignored in watershed planning and management. In the Dhrabi watershed of Pakistan, the quality of surface water was monitored at 16 locations to assess suitability for irrigation over regular intervals during the period 2007-2010. Similarly, groundwater quality was monitored at 10 locations for drinking and irrigation purposes. There was high spatial and temporal variability in surface water quality. Electrical conductivity (EC) and residual sodium carbonate (RSC) either exceeded or fluctuated around permissible limits at most of the locations throughout the monitoring period. Therefore, the use of such water for irrigation needs special care, otherwise its prolonged use may pose soil salinity and sodicity problems. The trend of EC and RSC for groundwater was similar to that for surface water. Exchangeable Mg2+ exceeded permissible limits for most of the surface water and groundwater samples. In addition, microbial analysis of groundwater revealed that only two out of eight monitoring points during August 2009, none out of eight points during February 2010, and one out of nine points during June 2010 provided water fit for drinking. Soil samples were collected from the catchment areas of the major contributing streams and from the beds of the Kallar Kahar Lake and the Dhrabi Reservoir. The soil samples from the catchments showed high salinity and sodicity that may be the cause of high salinity and sodicity in the streams. The highest EC, sodium adsorption ratio (SAP,) and exchangeable sodium percentage (ESP) in the bed samples from the Kallar Kahar Lake were about 43 dS/m, 56, and 45, respectively. These high values were due to the saline water brought into the lake with the runoff.
文摘Tank cascade system(TCS)is a series of tanks located in a meso-catchment and has been accepted as a Globally Important Agricultural Heritage System found in Sri Lanka.Ecosystem components of the TCS play a major role in purifying water within the system.This study attempted to investigate the water quality status and the farmers’willingness to rehabilitate the ecosystem components of the Thirappane TCS.Drinking and irrigation water quality parameters were tested in 34 locations and drinking and irrigation water quality indexes were calculated.Participatory rural appraisal and a questioner survey were conducted to gather social data.Water of TCS was observed to be appropriate for irrigation but not for drinking during the Maha cropping season.Based on the results of the Nitrate(as NO_(3)^(-))and Total Phosphate(as PO_(4)^(3-)),water of TCS can be categorized as eutrophic.Presence of ecosystem features of tank cascade system,annual income of the respondents,satisfaction on the quality of water for drinking,and the awareness about the tank cascade system significantly influenced the participatory decisions of the community on the rehabilitation of TCS.This study shall be an example and an eye opener to formulate sustainable tank cascade management plan.
基金supported financially by the Chinese National Science Foundation Project (41172310, 40171006)the Major State Basic Research Development Program (973) (2014CB238906)the National High Technology Research and Development Program (863) ofChina (2004AA601080, 2006AA06Z380)
文摘To study arsenic (As) content and distribution patterns as well as the genesis of different kinds of water,especially the different sources of drinking water in Guanzhong Basin,Shaanxi province,China,139 water samples were collected at 62 sampling points from wells of different depths,from hot springs,and rivers.The As content of these samples was measured by the intermittent flowhydride generation atomic fluorescence spectrometry method (HG-AFS).The As concentrations in the drinking water in Guanzhong Basin vary greatly (0.00-68.08 tg/L),and the As concentration of groundwater in southern Guanzhong Basin is different from that in the northern Guanzhong Basin.Even within the same location in southern Guanzhong Basin,the As concentrations at different depths vary greatly.As concentration of groundwater from the shallow wells (〈50 m deep,0.56-3.87 μg/L) is much lower than from deep wells (110-360 m deep,19.34-62.91 μg/L),whereas As concentration in water of any depth in northern Guanzhong Basin is 〈10 μg/L.Southern Guanzhong Basin is a newly discovered high-As groundwater area in China.The high-As groundwater is mainly distributed in areas between the Qinling Mountains and Weihe River; it has only been found at depths ranging from 110 to 360 m in confined aquifers,which store water in the Lishi and Wucheng Loess (Lower and Middle Pleistocene) in the southern Guanzhong Basin.As concentration of hot spring water is 6.47-11.94 μg/L; that of geothermal water between 1000 and 1500 m deep is 43.68-68.08 μg/L.The high-As well water at depths from 110 to 360 m in southern Guanzhong Basin has a very low fluorine (F) value,which is generally 〈0.10 mg/L.Otherwise,the hot springs of Lintong and Tangyu and the geothermal water in southern Guanzhong Basin have very high F values (8.07-14.96 mg/L).The results indicate that high As groundwater in depths from 110 to 360 m is unlikely to have a direct relationship with the geothermal water in the same area.As concentration of all reservoirs and rivers (both contaminated and uncontaminated) in the Guanzhong Basin is 〈10 μg/L.This shows that pollution in the surface water is not the source of the high-As in the southern Guanzhong Basin.The partition boundaries of the high-and low-As groundwater area corresponds to the partition boundaries of the tectonic units in the Guanzhong Basin.This probably indicates that the high-As groundwater areas can be correlated to their geological underpinning and structural framework.In southern Guanzhong Basin,the main sources of drinking water for villages and small towns today are wells between 110-360 m deep.All of their As contents exceed the limit of the Chinese National Standard and the International Standard (〉10 μg/L) and so local residents should use other sources of clean water that are 〈50 m deep,instead of deep groundwater (110 to 360 m) for their drinking water supply.
文摘Backgrounds: One of the fundamental needs of a community is to have an access to healthy and safe drinking water. The lack of a concentrated accessibility to health facilities and services is among the serious problems facing villagers in the rural areas. The aims of this research was to investigate the drinking water quality of the villages in Babol township suburbs in north of Iran. Materials and Methods: In this cross-sectional descriptive study, a total of 140 water samples were taken from the water distribution network in16 villages for the low and high-rain seasons in sterile glass bottle. The microbial quality of gathered samples were determined based on standard methods in laboratory. Statistical analysis of the results was performed using a SPSS16 statistical software. Findings: Based on obtained results 13.6% of the samples were contaminated to coliform and 20% to fecal coliform bacteria. The residual chlorine in 12.5% of the samples were between 0.2 to 0.8 mg·L-1 and the PH in total samples were between 6.8 to 7.8. There were no signs of any contamination for 32.86% of the analysed samples which water resources is located to a distance of more than 30 m to the contamination sources. In addition, 43.1% of the samples taken from the water resources with no plumbing system, have had a fecal contamination. Conclusions: Considering the results achieved, the microbial quality of the drinking water of the studied villages classified as “moderate” status. For more water supply there is not sufficient residual chlorine in most cases. Poor sanitation of water supply is most causes of water contamination. It is therefore strongly recommended that sanitation measures are made to protect water resources from the contamination.
文摘Minerals and constitutes in drinking water are vital for the nutrition of human bodies. Certain limits of water quality parameters must be met to ensure the safety of bottled drinking water for the human consumption. Thirty two local and twelve imported brands of bottled water in Saudi Arabia have been collected to verify their compliance with international and local standards which are EPA (2016), WHO (2013) and SASO (2009). A proposed scoring system is used to evaluate the water quality. Fayha and Hilwa brands have been selected as the best local brands whereas Volvic brand as the optimal imported brand in the western region of Saudi Arabia. The local water brands are more reliable to the standards than the imported brands. Licensed water brands in Saudi Arabia are found to have a good water quality which satisfied the quality requirements.
基金Higher Education Commission of Pakistan,who has provided financial support for this research work through the project Evaluation of the groundwater and explore recharge zone of depleting aquifer in the Quetta valley(Project No:9474/Punjab/NRPU/R&D/HEC/2017)。
文摘Water is an essential element on earth,which provides human a variety of services in domestic use,agriculture,or industries.However,some serious health risks of drinking water are associated with microbial contamination,particularly with fecal matter.Therefore,microbial quality assessment is considered to be a necessary component of water quality assessment.This study investigates microbial contamination of water distributary system around the city by comparing groundwater(GW)and tap water(TW)quality in Quetta city.31 GW samples and 31 TW samples were collected in the study area during the months of September,October,and November.Fecal coliform test was carried out in laboratory and their average total coliform contamination was computed.Results showed that the TW sample were all contaminated by coliform except for Chiltan town,hence are not considered suitable for drinking without any treatment according to WHO drinking water quality standards.The average coliform concentrations were 12 in Quetta main city,11.6 in Jinnah town,5.3 in Satallite town,10 in Shahbaz town and 5 in Brewery town(0/100 mL CFU)and the TW samples from the three towns were even more contaminated with E.coli.Whereas among the GW,average microbial concentrations were 1.8 in Quetta main city,2 in Satallite town,1.4 in Shahbaz town,and 0.4 in Chiltan town(0/100 mL CFU),respectively,which shows that the contamination is occurring within the water distributary pipeline system when the water flows through the pipelines.Moreover,this research will be valuable for researchers and administrative authorities to conduct elaborative studies,and develop new policies to prevent further deterioration of drinking water in the water distribution system by pathogenic microorganisms and ensure safe drinking water to the public of Quetta city.
文摘To investigate the water quality of sampling in aquaculture ponds around the basic farmland protection areas in the five districts of Foshan city, and use the environmental pollution index to evaluate the condition of water quality. The results indicated that water temperature and pH of aquaculture ponds cound meet the requirements of fish normal growth,and dissolved oxygen was rich, but the water quality was over fertilized generally. In 20 investigation spots of the five districts, the content of CODCr, NH4^+-N and TP exceeded 90%, 30% and 85% respectively. The pollution degrees of the water quality from high to low in aquaculture ponds were Chancheng district,Nanhai district, Sanshui district, Shunde district, Gaoming district. The comprehensive quality index of aquaculture ponds was 1.44 in Foshan city, the water quality was polluted severly as a whole. The share rate of pollution load of TP was the highest, the second were CODCr and NH4^+-N. On the whole, the pollution of organic matter was very prominent in the water quality of aquaculture ponds around the basic farmland protection areas in Foshan city that had been eutrophicated.
文摘The present study aims at measuring the activity concentrations of ^210Po and ^210Pb in the potable water of Eloor, a major industrial belt in the Ernakulam district of Kerala, India with an aim of evaluating resultant ingestion dose to critical population. The industrial units located in Eloor discharge their treated effluents into the river Periyar and the surrounding environs. The two major industries of interest with respect to NORMs are the fertilizer plant, processing rock phosphate and the monazite processing plant, which had been in operation for the last 50 years. For sampling, Eloor region was divided into four zones and a total of 55 water samples from different locations were collected and analysed as per standard analytical procedure manual of BARC. The ^210Po concentration ranged between 0.3 to 4.7 mBq.L^-1 and ^210Pb ranged from 0.6 to 4.3 mBq.L^-1. All values are well below the limit of 0.1 Bq.Ll recommended by World Health Organization. Statistical analysis shows a good co-relation between ^210Po and ^210Pb in the water samples analyzed and the mean activity concentration is found to be relatively high in the western region of Eloor compared to other regions. The annual effective dose equivalent to man from ^210Po and ^210Pb through drinking water intake were estimated and found to be 1.13 μSv.y^-1 and 0.99 μSv.y^-1 respectively, which is well below the reference level of committed effective dose (100 μSv.y^-1) recommended by WHO.
基金Jiangsu Suxie Academy of Environmental Technology for its support for the program"Study on the linkage system for emergency monitoring of water sources of the Yangtze River"(No.1203)~~
文摘The Yangtze River flows through Jiangsu Province, bringing abundant water resources to people in this province. However, environmental pollution and destruction of vegetation in recent years have led to deterioration of water quality of the Yangtze, bringing about many bad effects on people’s life and production. Through a comprehensive analysis of water quality of the Yangtze River through Jiangsu Province, we investigated the reasons for the deterioration of its water quality, and explored countermeasure to maintain good water quality in the Yangtze with the objective to provide safe and reliable drinking water sources for people.
文摘Clean drinking water is one of the United Nations Sustainable Development Goals.Despite significant progress in the water purification technology,many regions still lack access to clean water.This paper provides a review of selected water contaminants and their impacts on human health.The World Health Organization(WHO)guidelines and regional standards for key contaminants were used to characterise water quality in the European Union and UK.The concept of safe drinking water was explained based on the non-observed adverse effect level,threshold concentrations for toxic chemicals,and their total daily intake.Various techniques for monitoring water contaminants and the drinking water standards from five different countries,including the UK,USA,Canada,Pakistan and India,were compared to WHO recommended guidelines.The literature on actual water quality in these regions and its potential health impacts was also discussed.Finally,the role of public water suppliers in identifying and monitoring drinking water contaminants in selected developed countries was presented as a potential guideline for developing countries.This review emphasised the need for a comprehensive understanding of water quality and its impacts on human health to ensure access to clean drinking water worldwide.
基金This work was supported by the National Natural Science Foundation of China(Grant No.50538090).
文摘The continuously deteriorating quality of source water is threatening the safety of drinking water in China.Various efforts have been made to update water treatment processes to decrease the pollution problems of drinking water,such as protection of drinking water sources,enhance-ment of conventional treatment processes,and development of new or advanced treatment technologies.This paper reviews a variety of protection and remediation methods for drinking water sources,development and application of drinking water treatment technologies,new technologies for special pollutants removal from groundwater,and the latest research progress on water distribution systems in China.
基金the International Foundation for Science(IFS)for contributing to this work.
文摘The present study assesses the physicochemical and bacteriological quality of the drinking water used by the population of S?-Ava based on the Beninese standards and those established by the World Health Organization (WHO). In rural and peri-urban areas of Benin where public water supply systems are inadequate or almost non-existent, the population consumes water of various sources of unknown qualities. A total of 67 water samples were analyzed during the rainy season (July 2017) and in the dry season (January 2018) for certain physical, chemical and bacteriological parameters using the standard methods. The results of the analyses reveal that the physicochemical characteristics of the water used for consumption in S?-Ava comply with the drinking water standards of the World Health Organization and those in force in Benin except for the percentages of the following parameters: pH (41.80%);turbidity (25.37%);the color (16.42);ammonium (17.91%);iron (40.30%);Nitrites (4.48%);Residual chlorine (91.05). Bacteriologically, the analyses showed a high total aerobic mesophilic flora contamination, faecal coliforms, E. coli, faecal enterococci respectively in 89.55%, 82.09%, 50.75% and 70.15% of the analyzed water samples. The ratio of faecal coliforms to faecal enterococci indicated that the origin of faecal contamination was human in 59.7% of the samples and animal in 40.3% of the samples. The adoption of hygiene measures at the water point, during the transport and storage of water, including the treatment by chlorination of drinking water at the family level was recommended for the population concerned and household awareness on the adoption of basic hygiene and sanitation measures have been recommended for hygiene and sanitation services.
文摘Sustaining a reliable and contaminant-free drinking water is becoming an increasing challenge worldwide due to human activity, industrial waste, and agricultural overuse. Surface water is the main source of drinking water around the world. However, groundwater is also becoming increasingly popular, due to its clarity and minimal need for processing to reduce turbidity. Over the years, the demand and growth in the agricultural industry has also been the means of groundwater contamination. Due to the health burden that raw water can pose, water must be processed and purified prior to consumption. Raw water quality can be compromised by physical, chemical (heavy metals and disinfection by-products), and biological contaminants. Biological contaminants can significantly impact immunocompromised populations, while chemical contaminants can impact the growth and development of young children. Although obtaining a steady and high-quality water flow to the general population is an increasing challenge, developed countries have utilized state-of-the-art technologies and techniques to provide contaminant-free water to their citizens. This research aims to provide information about the regulatory parameters, characteristics, and sources of safe drinking water in the world as a model for future use in the developing world. In this, secondary data was used to compare and contrast drinking water quality among countries in the European Union, the United States, Canada, the United Kingdom, Singapore, New Zealand, Australia, Qatar, and the United Arab Emirates. The data indicates that Ireland and the United Kingdom have relatively lower amounts of contaminants in their drinking water. Upon completing this research, it is recommended that countries desiring clean drinking water systems should initiate and invest in programs that control and protect treatment plants, water distribution systems, water sources, and catchments.