Abstract
In the Millennium Development Goals, the safe drinking-water target is measured by "access to improved water sources, " and thus does not always reflect the water safety in terms of water quality. Therefore, it is important to develop a method to assess the actual percentages of the population with access to "safe drinking water." The Household Water Treatment (HWT) is one of the possible solutions to improve the safety of water supply; however, their actual use and performance in households remains unknown. In this study, we conducted a face-to-face questionnaire survey (5 communes) and a water quality survey (12 communes) to estimate the population having access to safe drinking water in Hanoi city, Vietnam. Our questionnaire survey revealed that 37-84% of the households used HWTs and that the most prevalent types were Reverse Osmosis (RO) unit in the urban and suburban areas, and Sand Filter (SF) unit in the rural area. Based on the water quality survey, it was estimated that only 11% (n = 23) of the household wells and 35% (n = 23) of the piped water supply samples met WHO guideline values both for arsenic and E. coli. Combining the results of the questionnaire survey and the water quality survey, it was estimated that access to safe drinking water of urban, suburban and rural areas were 60%, 15% and 52%, respectively. These access percentages were estimated to be improved by 13%, 20% and 8%, respectively, by the usage of HWTs, which revealed the important role of HWTs for getting access to safe drinking water.
