To meet the Millennium Development Goal (MDG) for sanitation, some 450m additional households will require services by 2015; 60% of these are in urban areas. A recent Stockholm Environment Institute (SEI) study1 indicates that the MDG urban sanitation target will not be met through conventional water treatment alone, due to prohibitive costs and infrastructure requirements. One alternative for rural and urban areas is “eco-sanitation”, including dry toilets that use urine diversion and faecal sanitization and the composting and recycling of nutrients for agricultural use. “Eco-toilets” are an affordable, feasible option that may be scaled up for use in larger communities. Eco-sanitation systems have already been successful China in both rural and urban areas, and in Vietnam, South Africa, Mexico and El Salvador, to name a few.

Ecological sanitation can meet a signifi- cant proportion of fertiliser needs while helping to improve the capacity of the soil to hold water. In sub-Saharan Africa adopting this approach could replace almost all the commercial fertilisers currently used that are based on fossil fuels and finite resources.

However boosting soil nutrient levels is not the only way of eradicating global hunger. To produce enough food to halve the world’s undernourished population by 2015, fresh water consumption will need to increase by 50%. Producing food uses more water than any other human activity. It takes 4,000 litres of fresh water per day to provide food for just one person. This adds up to 1,300 cubic metres per person per year. Some countries, such as India, Kenya and Nigeria, would have to double current fresh water use, even after the benefits of crop-per-drop (increased yield through more efficient use of water) improvements are factored in.

While irrigation will continue to be important, it does present limitations and cannot solve the problem alone. The emphasis must be placed on crop-per-drop improvements targeting rain-fed agriculture. We will need improved land management practices that increase the soil’s water content. The necessary techniques are available, though new and not yet widespread.

There is a strong correlation between poverty, hunger and unreliable rainfall. This is a major challenge to researchers and policy makers. The countries most seriously affected by these issues also face the highest risk of water scarcity, huge variations in rainfall and frequent droughts and flooding. The need for more water for food production will result in trade-offs with human use downstream and other terrestrial and aquatic ecosystems. Major increases in the use of fresh water for food production in the near future will require joint efforts to balance the needs of humans and nature. Moreover to reduce world hunger by 50% over the next 10 years, 1.2 m sq km of land will need to be converted to rain-fed agriculture from other uses.

With clear links between the issues of water, sanitation, health, poverty and hunger, there is an urgent need to find intelligent integrated strategies for managing fresh water, land use and sanitation.

1. See www.sei.se for downloadable version of the report “Sustainable Pathways to Attain the Millennium Development Goals: Assessing the Key Role of Water, Energy and Sanitation”, Stockholm Environment Institute (2005).