scholarly journals Inequalities in microbial contamination of drinking water supplies in urban areas: the case of Lilongwe, Malawi

2016 ◽  
Vol 14 (5) ◽  
pp. 851-863 ◽  
Author(s):  
Akosua Sarpong Boakye-Ansah ◽  
Giuliana Ferrero ◽  
Maria Rusca ◽  
Pieter van der Zaag
Keyword(s):  
Escherichia Coli ◽  
Water Quality ◽  
Drinking Water ◽  
Water Supply ◽  
Low Income ◽  
Urban Areas ◽  
Microbial Contamination ◽  
Water Storage ◽  
Faecal Contamination ◽  
Household Level

Over past decades strategies for improving access to drinking water in cities of the Global South have mainly focused on increasing coverage, while water quality has often been overlooked. This paper focuses on drinking water quality in the centralized water supply network of Lilongwe, the capital of Malawi. It shows how microbial contamination of drinking water is unequally distributed to consumers in low-income (unplanned areas) and higher-income neighbourhoods (planned areas). Microbial contamination and residual disinfectant concentration were measured in 170 water samples collected from in-house taps in high-income areas and from kiosks and water storage facilities in low-income areas between November 2014 and January 2015. Faecal contamination (Escherichia coli) was detected in 10% of the 40 samples collected from planned areas, in 59% of the 64 samples collected from kiosks in the unplanned areas and in 75% of the 32 samples of water stored at household level. Differences in water quality in planned and unplanned areas were found to be statistically significant at p < 0.05. Finally, the paper shows how the inequalities in microbial contamination of drinking water are produced by decisions both on the development of the water supply infrastructure and on how this is operated and maintained.

scholarly journals Household stored water quality in an intermittent water supply network in Panama

2020 ◽  
Vol 10 (2) ◽  
pp. 298-308
Author(s):  
Carlos I. Gonzalez ◽  
John Erickson ◽  
Karina A. Chavarría ◽  
Kara L. Nelson ◽  
Amador Goodridge
Keyword(s):  
Water Quality ◽  
Drinking Water ◽  
Water Supply ◽  
Water Storage ◽  
Total Coliform ◽  
Drinking Water Supply ◽  
Coliform Bacteria ◽  
Plate Count ◽  
Probable Number ◽  
Total Coliform Bacteria

Abstract Safe water storage is critical to preserve water quality, especially when intermittent piped drinking water supply creates a need for household storage. This study characterized household storage practices and stored water quality in 94 households (N = 94) among four peri-urban neighborhoods in Arraiján, Panama with varying degrees of supply intermittency. We found that 18 (19.1%) households stored drinking water in unsafe containers. Forty-four (47%) samples of household stored drinking water had residual chlorine levels <0.2 mg/L. While 33 (35.1%) samples were positive for total coliform bacteria, only 23 (24.4%) had >10 most probable number (MPN)/100 mL total coliform bacteria. Eight (44%) samples were positive for Escherichia coli, whereas only one (1.3%) sample from the safe containers was positive. Twenty-nine (30.9%) samples had >500 MPN/mL heterotrophic plate count bacteria. These findings suggest that longer supply interruptions were associated with longer storage times and lower chlorine residual, which were associated with higher concentrations of indicator bacteria. This is one of the first studies in the Central-American region to show an association between the lack of turnover (replacement with fresh water) and greater contamination during household water storage. Thus, when drinking water supply is not completely continuous and household storage is required, decreasing the time between supply periods can facilitate safer water storage. Public awareness and education are also recommended to increase hygiene practices during water collection and storage.

scholarly journals The utility of Escherichia coli as a contamination indicator for rural drinking water: Evidence from whole genome sequencing

PLoS ONE ◽  
2021 ◽  
Vol 16 (1) ◽  
pp. e0245910
Author(s):  
Saskia Nowicki ◽  
Zaydah R. deLaurent ◽  
Etienne P. de Villiers ◽  
George Githinji ◽  
Katrina J. Charles
Keyword(s):  
Escherichia Coli ◽  
Drinking Water ◽  
Whole Genome Sequencing ◽  
Genome Sequencing ◽  
Allelic Diversity ◽  
Source Tracking ◽  
Whole Genome ◽  
Faecal Contamination ◽  
Household Level ◽  
Phylogenetic Grouping

Across the water sector, Escherichia coli is the preferred microbial water quality indicator and current guidance upholds that it indicates recent faecal contamination. This has been challenged, however, by research demonstrating growth of E. coli in the environment. In this study, we used whole genome sequencing to investigate the links between E. coli and recent faecal contamination in drinking water. We sequenced 103 E. coli isolates sampled from 9 water supplies in rural Kitui County, Kenya, including points of collection (n = 14) and use (n = 30). Biomarkers for definitive source tracking remain elusive, so we analysed the phylogenetic grouping, multi-locus sequence types (MLSTs), allelic diversity, and virulence and antimicrobial resistance (AMR) genes of the isolates for insight into their likely source. Phylogroup B1, which is generally better adapted to water environments, is dominant in our samples (n = 69) and allelic diversity differences (z = 2.12, p = 0.03) suggest that naturalised populations may be particularly relevant at collection points with lower E. coli concentrations (<50 / 100mL). The strains that are more likely to have originated from human and/or recent faecal contamination (n = 50), were found at poorly protected collection points (4 sites) or at points of use (12 sites). We discuss the difficulty of interpreting health risk from E. coli grab samples, especially at household level, and our findings support the use of E. coli risk categories and encourage monitoring that accounts for sanitary conditions and temporal variability.

Quality Perceptions and Water Treatment Behavior at the Household Level

2019 ◽  
Vol 05 (03) ◽  
pp. 1850024 ◽  
Author(s):  
Anna-Maria Aksan ◽  
William F. Vásquez
Keyword(s):  
Water Quality ◽  
Drinking Water ◽  
Low Income ◽  
Bottled Water ◽  
Low Income Countries ◽  
Contaminated Water ◽  
Information Campaigns ◽  
Household Level ◽  
Quality Perceptions ◽  
Aesthetic Characteristics

Contaminated drinking water is a major contributor to illnesses in low-income countries. Individuals may take measures to avoid drinking contaminated water, by boiling, filtering, or chlorinating it, or by drinking bottled water. However, lack of information about water quality in some communities may lead individuals to perceive water quality to be better than it could be and therefore not allocate sufficient resources to avoid drinking contaminated water, or to perceive water quality to be worse than it is thereby wasting resources on treating the water or buying bottled water. We build an expected utility model to demonstrate that individuals may over or under invest in improving drinking water depending on their perceptions of water quality. Perceptions depend on uncertain health outcomes as well as other potentially confounding influences (e.g., aesthetic characteristics of the water and cultural norms). Simulations demonstrate conditions under which individuals correct their perceptions over time versus when policy interventions (e.g., information campaigns) may effectively correct perceptions.

scholarly journals Household-level drinking water quality, access, and management practices within an informal community: a case study at Rio das Pedras, Rio de Janeiro

2018 ◽  
Vol 9 (1) ◽  
pp. 80-89 ◽  
Author(s):  
Richard V. Remigio ◽  
Renata S. Rabello ◽  
Garazi Zulaika ◽  
Marilia S. Carvalho ◽  
Paulo R. G. Barrocas ◽  
...  
Keyword(s):  
Water Quality ◽  
Drinking Water ◽  
Water Supply ◽  
Rio De Janeiro ◽  
Management Practices ◽  
Water Storage ◽  
Bottled Water ◽  
Household Characteristics ◽  
Piped Water ◽  
At Home

Abstract Inter-household patterns in drinking water access, consumption, perception, and quality among residents can vary in Rio das Pedras (RdP), a large favela in Rio de Janeiro, Brazil. While unreliable water quality can influence residents to diversify their drinking water supply, household drinking water management practices are not generally known for this community. Household surveys, and indoor tap, piped water before entering the home, filtered, or bottled dispenser water samples were collected. Respondents reported storing water (91%) and near-daily access to piped water (78%). A majority of households reported cleaning water storage tanks at least once every 6 months. Also, residents rely on bottled water and a considerable proportion supplemented their water supply with at-home filtered water. The quality and safety of these sources are not necessarily superior to indoor tap water, especially under conditions of appropriate water storage tank cleaning. Higher prevalence of total coliform detections was found in indoor tap, filtered, and bottled water. Household characteristics such as home ownership, residence type, and residence time exhibited a positive association with improved tank cleaning. Community health practitioners could evaluate practices in water storage, at-home filtration maintenance, and bottled water dispenser systems using household characteristics to promote protective actions.

scholarly journals The effectiveness of large household water storage tanks for protecting the quality of drinking water

2007 ◽  
Vol 5 (2) ◽  
pp. 307-313 ◽  
Author(s):  
Jay P. Graham ◽  
James VanDerslice
Keyword(s):  
Water Quality ◽  
Drinking Water ◽  
Water Supply ◽  
Storage Tank ◽  
Water Storage ◽  
Free Chlorine ◽  
Drinking Water Quality ◽  
Water Delivery ◽  
Storage Tanks ◽  
Total Coliforms

Many communities along the US-México border remain without infrastructure for water and sewage. Residents in these communities often collect and store their water in open 55-gallon drums. This study evaluated changes in drinking water quality resulting from an intervention that provided large closed water storage tanks (2,500-gallons) to individual homes lacking a piped water supply. After the intervention, many of the households did not change the source of their drinking water to the large storage tanks. Therefore, water quality results were first compared based on the source of the household's drinking water: store or vending machine, large tank, or collected from a public supply and transported by the household. Of the households that used the large storage tank as their drinking water supply, drinking water quality was generally of poorer quality. Fifty-four percent of samples collected prior to intervention had detectable levels of total coliforms, while 82% of samples were positive nine months after the intervention (p &lt; 0.05). Exploratory analyses were also carried out to measure water quality at different points between collection by water delivery trucks and delivery to the household's large storage tank. Thirty percent of the samples taken immediately after water was delivered to the home had high total coliforms (&gt;10 CFU/100 ml). Mean free chlorine levels dropped from 0.43 mg/l, where the trucks filled their tanks, to 0.20 mg/l inside the household's tank immediately after delivery. Results of this study have implications for interventions that focus on safe water treatment and storage in the home, and for guidelines regarding the level of free chlorine required in water delivered by water delivery trucks.

scholarly journals Bacteriological assessment of bottled drinking water in 5 provinces of central highland, VietNam

2019 ◽  
Vol 2 (3) ◽  
pp. 86-89
Author(s):  
Thuan Nguyen Vu ◽  
Doanh Pham Van ◽  
Thu Hien Nguyen Thi ◽  
◽  
◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Water Quality ◽  
Pseudomonas Aeruginosa ◽  
Drinking Water ◽  
Microbial Contamination ◽  
Total Coliform ◽  
Bottled Drinking Water ◽  
Bacteriological Quality ◽  
Drinking Water Standard ◽  
Central Highland

The assessment of the bacteriological quality among 390 samples of bottled drinking water was studied. The samples were tested for Escherichia coli, Clostridia, total Coliform, Streptococci feacal and Pseudomonas aeruginosa. The rates of microbial contamination in bottled drinking water were of 56.7% (2017) and 50.7% (2018). The samples failed to meet QCVN drinking water standard of acceptable limits of bacterial presence including Pseudomonas aeruginosa (41.5%), total Coliform (11.8%), Clostridia (4.6%); Escherichia coli (4.9%) and Streptococcifeacal (1.3%). It is necessary to strengthen the inspection, supervision, propagation, and education that give warnings, ensure water quality and raise the awareness of producers, traders and consumers.

scholarly journals Urban drinking water security in Gujarat

2021 ◽  
Author(s):  
Meera Mehta ◽  
Dinesh Mehta ◽  
Jaladhi Vavaliya
Keyword(s):  
Drinking Water ◽  
Water Supply ◽  
Urban Areas ◽  
Water Security ◽  
Assessment System ◽  
Service Levels ◽  
Household Level ◽  
Urban Drinking Water ◽  
Water Scarce ◽  
Key Aspects

AbstractGujarat has made important strides to ensure that most parts of the state become water secure. In 2005, Gujarat was one of the few states that recognized that its urban areas were its ‘engines of growth’ and made significant investments in urban infrastructure. A state-wide water supply grid was constructed to transfer inter-basin water from perennial surface water sources to water-scarce areas. While these schemes have improved household-level access to municipal water supply, service levels have not improved. In this paper, we argue that along with infrastructure creation, there is a need to focus on monitoring, operation and maintenance of existing system and improving efficiency. We analyze information available from the performance assessment system (PAS) setup by the CEPT University for monitoring of urban services in India. It has annual information of water service delivery in all the urban areas of Gujarat from 2010. We assess urban drinking water supply on three key aspects: equity, service quality and financial sustainability. We also identify a few key intervention areas related to increased accountability, efficiency and equity in delivery of water supply services.

Methodological Approaches to Organization of Drinking Water Quality Monitoring Programs

2020 ◽  
pp. 4-8
Author(s):  
Yu.A. Novikova ◽  
I.O. Myasnikov ◽  
A.A. Kovshov ◽  
N.A. Tikhonova ◽  
N.S. Bashketova
Keyword(s):  
Water Quality ◽  
Drinking Water ◽  
Water Supply ◽  
Cold Water ◽  
Water Quality Monitoring ◽  
Drinking Water Quality ◽  
Quality Monitoring ◽  
Water Supply Systems ◽  
Monitoring Programs ◽  
Supply Systems

Summary. Introduction: Drinking water is one of the most important environmental factors sustaining life and determining human health. The goal of the Russian Federal Clean Water Project is to improve drinking water quality through upgrading of water treatment and supply systems using advanced technologies, including those developed by the military-industrial complex. The most informative and reliable sources of information for assessing drinking water quality are the results of systematic laboratory testing obtained within the framework of socio-hygienic monitoring (SGM) and production control carried out by water supply organizations. The objective of our study was to formulate approaches to organizing quality monitoring programs for centralized cold water supply systems. Materials and methods: We reviewed programs and results of drinking water quality laboratory tests performed by Rospotrebnadzor bodies and institutions within the framework of SGM in 2017–2018. Results: We established that drinking water quality monitoring in the constituent entities of the Russian Federation differs significantly in the number of monitoring points (566 in the Krasnoyarsk Krai vs 10 in Sevastopol) and measured indicators, especially sanitary and chemical ones (53 inorganic and organic substances in the Kemerovo Region vs one indicator in the Amur Region). Discussion: For a more complete and objective assessment of drinking water quality in centralized cold water supply systems, monitoring points should be organized at all stages of water supply with account for the coverage of the maximum number of people supplied with water from a particular network. Thus, the number of points in the distribution network should depend, inter alia, on the size of population served. In urban settlements with up to 10,000 inhabitants, for example, at least 4 points should be organized while in the cities with more than 3,000,000 inhabitants at least 80 points are necessary. We developed minimum mandatory lists of indicators and approaches to selecting priority indices to be monitored at all stages of drinking water supply.

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