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The effects of an intermittent piped water network and storage practices on household water quality in Tamale, Ghana

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The United Nations Millennium Development Goals include a target to halve the number of people without access to "improved" water sources, which include piped water supply. However, an "improved" source of water does not necessarily indicate a safe source. The city of Tamale in northern Ghana has a piped water network that supplies treated water, but the system is intermittent and many users only have access to piped water several days per week. In order to have sufficient supply of water, users are forced to store large quantities of water in their homes, sometimes in unsanitary storage containers. Samples taken from households around Tamale indicate that there is widespread contamination of drinking water as indicated by total coliform, E. coli, and lack of chlorine residual. Examination of data from Ghana Water Company Limited, the local utility shows that water quality is being degraded between the treatment plant outlet and use by households. This degradation could be caused by low-pressure situations in the intermittent distribution system, allowing contaminants to enter the system. The contamination could also be caused by unhygienic water storage practices in the home, such as storing water in open containers and dipping unwashed hands into the water supply. Interviews conducted in 40 households show that many households do not practice hygienic water storage and handling. In the short term, it is recommended that local NGOs or local government agencies increase efforts to educate users about proper water handling and storage practices to decrease bacteriological contamination of drinking water in the home. In the long-term, it is recommended that the intermittency of the system be decreased by improving maintenance on pipelines and removing illegal connections.
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... The duration of supply that characterizes this type of water distribution is also a point of divergence in the literature. The temporal restriction is well established and emphasized everywhere [24,25], but some authors distance themselves from the less than 24 h in a day limitation, widening the spectrum to a supply to end users lasting anywhere from limited hours a day to only on a few days a week or less [4,7,[26][27][28]. ...
... Health risks: Water quality and health hazard [6,9,28,43]; • Technical problems: Network wear [17,26,39]; Difficulty in detecting and repairing leaks [5]; • Economic issues: The cost of network wear; Metering and billing issues [44,45] • Social and political problems: Illegal connections and other customers' coping strategies [10,39,46,47]; Inequity of water supply [7,10,48,49]; Water wastage [5,7]; ...
... In addition, because it fails to deliver an adequate service to the consumers, namely available water when needed, intermittency leads the consumers to the use of complementary systems such as domestic water storage accommodations, like a water tank on the house roof, cistern, or other permanent deposit at home [10,18,44,46,47,[50][51][52]. Because of its stagnation in domestic tanks or reservoirs, water quality is deteriorated again at the consumer's side [28,31,[53][54][55], even if there is a regulation of the construction and maintenance of these thanks, this type of installation is private property. In practice, they are rarely built, controlled, and maintained according to standards that take into consideration prevention against contamination. ...
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... A comprehensive water quality monitoring program should be conducted throughout distribution systems for several parameters, including chlorine residual, bacteriological and physical measurements (Hesby, 2005). And if any of samples test positive for coliforms bacteria, a further test to detect E. coli presence should be conducted (Vacs Renwick, 2013). ...
... Table 2 also shows that 10 of totally 38 samples with chlorine residual range of 0.00 -0.20 mg/l have coliforms, while none is detected at other chlorine residual ranges. It supports the approach of research by Vacs Renwick (2013), who assumed the water will be coliform free if the average chlorine residual is above 0.2 mg/l, although The World Health Organization recommended a safer approach of minimally 0.5 mg/l chlorine residual after at least 30 minutes contact time. The later minimum value is also applied when potential waterborne disease occurs or when faecal contamination of a drinking-water supply is detected (World Health Organization, 2011;Ratnayaka, et al., 2009). ...
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Even though the water is supplied from Water Treatment Plant 24 hours a day, some consumers of Tirta Daroy Water Supply Company receive water in their taps intermittently. This condition leads to several reported pipe breaks and coliforms presence, as well. Tirta Daroy conducts a quality control activity so called Pamkor on regular basis. This study is conducted to analyse data obtained from this activity during 2014, with the focus on the total coliforms for total 161 sampling connections. The result demonstrates that the coliforms presence is encouraged by the low chlorine residual and intermittent supply. Additional finding shows these two conditions occur mainly at the areas which have long distance to the water treatment plant.
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... Por el contrario, otros estudios existentes se focalizan en campañas de monitoreo y análisis de laboratorio para estudiar: la influencia de la temperatura y tiempo de almacenamiento en el aumento de la actividad microbiana [15]; la influencia de los depósitos en la variación de los parámetros de calidad antes y después del almacenamiento [16]; la influencia de los materiales de construcción de los depósitos y de su respectivo mantenimiento en la pérdida de calidad física, química y microbiológica del agua [17]; los efectos del servicio intermitente en depósitos de almacenamiento de agua en Tamale(Gana) [18]; el tipo de mezcla y patrones de demanda en depósitos elevados a escala de laboratorio comparando los resultados mediante técnicas computacionales [19]; la calidad del agua del grifo, depósitos privados y dispensadores de agua filtrada analizando el cloro libre residual, color, turbidez, pH, conductividad, patógenos(E.Choli), sólidos totales [20]. ...
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... Such are the works of Batish (2003);Sashikumar et al. (2003); Vairavamoorthy et al. (2007a) and Vairavamoorthy et al. (2008). Other studies, such as those of Tokajian and Hashwa (2003); Ayoub and Malaeb (2006) and Renwick (2013), deal with the effect of IWS policies on water quality. ...
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Domestic transmission routes of pathogens: the problem of in-house contamination of drinking water during storage in developing countries
  • Peter Jensen
  • Kjaer
  • H J Jeroen
  • Gayathri Ensink
  • Jayasinghe
Jensen, Peter Kjaer, Jeroen H.J. Ensink, Gayathri Jayasinghe, Wim van der Hoek, Sandy Cairncross, and Anders Dalsgaard. "Domestic transmission routes of pathogens: the problem of in-house contamination of drinking water during storage in developing countries." Tropical Medicine and Internation Health 7, no. 7 (July 2002): 604-609.