Policy Forum Water Supply and Health

A safe, reliable, affordable, and easily accessible water supply is essential for good health. Yet, for several decades, about a billion people in developing countries have not had a safe and sustainable water supply. It has been estimated that a minimum of 7.5 litres of water per person per day is required in the home for drinking, preparing food, and personal hygiene, the most basic requirements for water; at least 50 litres per person per day is needed to ensure all personal hygiene, food hygiene, domestic cleaning, and laundry needs [1]. This domestic water consumption is dwarfed by the demands of agriculture and ecosystems, even in wealthy countries where per capita domestic water consumption greatly exceeds these figures [2]. To cover all these requirements and to avoid water stress, experts generally agree that about 1,000 cubic metres of freshwater per capita per year is needed [3]. A key target of Millennium Development Goal (MDG) 7, which aims to ensure environmental sustainability, is ‘‘to reduce by half the proportion of people without sustainable access to safe drinking water and basic sanitation by 2015’’ [4]. This water supply target underpins several other MDGs, including those relating to poverty (MDG1), education (MDG2), and gender equality (MDG3). In particular, it underpins MDG4, the reduction of child mortality, because many deaths in young children in developing countries are due to diarrhoeal disease, and unsafe water is a key risk factor for diarrhoeal disease in this age group [5]. The WHO/UNICEF Joint Monitoring Programme for Water-supply and Sanitation (JMP), which monitors progress on the MDG water supply target, identifies three categories of drinking water supply: (a) water piped into the dwelling, plot, or yard; (b) other improved sources (including public taps, protected springs, hand pumps, and rainwater harvesting); and (c) unimproved sources (open water, unprotected from contamination) [6]. JMP assumes that ‘‘improved’’ water should be available not only for drinking but also for food preparation and personal and home hygiene, but it provides no official definition of how near a water source should be to a dwelling to be called improved. However, a distance of ,1,000 m has been suggested as an appropriate distance for meeting the MDG targets [7]. In poorly served countries, achieving the MDG water supply target will involve increasing water availability for domestic uses, improving water quality, and bringing about changed water-use and watermanagement habits. In the wealthy countries where adequate quantities of domestic water are already available on demand, the main task over the next few years will be to sustain water quality given the increasing pressures of pollution. However, global water supply targets need to be tempered by a recognition of the real demand (as expressed in user willingness and ability to pay), which may be less ambitious than the internationally agreed target. Furthermore, account needs to be taken of the realities of frequently poor levels of functionality. It is relatively easy to increase coverage through construction of water supply systems, but it is much more difficult to ensure that such systems continue to provide service over the long term. We therefore argue in this paper for a serious commitment by national governments and their partners to ensure adequate water supply services for all (the MDG target, if met, would still leave 672 million people with an unimproved supply [6,8]). In addition, we call for increased attention to be paid to ensuring continuing service provision. This will mean finding new ways to enhance public demand for improved services (that might translate into a willingness to pay), and a public and private sector ethos that puts high value on the quality of construction and ongoing service delivery.