In 1992, delegates to the United Nations Conference on Environment and Development (UNCED) in Rio de Janeiro recommended the establishment of an international day to highlight problems of water scarcity and safe drinking water. Since 1993, 22 March has officially been designated World Water Day. This year's tagline is "The world is thirsty because we are hungry".
We should drink one to two litres of water every day: by now this is a health mantra. Unfortunately, what is a recommended habit for many of us, is in fact a major challenge for the almost 1.2 million people (one fifth of the world's population), who live in areas of water scarcity. According to water.org, 884 million people lack access to safe drinking water, and more than 3.5 million people die each year from a water-related disease (84% of these are children). Recent estimates suggest that while it is highly desirable that we each drink two litres of water a day, the actual amount of water needed per person per day (for washing, cooking, etc.) ranges from 25 to 100 litres.
Without this ’blue gold‘, vegetables cannot be grown and animals cannot be fed; without clean water we cannot meet our basic sanitary needs, and the risk of infections is high.
Efficient water use and effective water management vary widely from one country to another and not all countries face the same challenges. African countries in general struggle to keep droughts at bay; China suffers from disastrous flooding, partly caused by poor river management; and South America strives to protect the precious biodiversity of wetlands, threatened by years of land misuse.
We asked Akiça Bahri (TWAS Fellow 2003), to give us some more specific information about water management. She is well qualified to do so: currently Coordinator of the African Water Facility in Tunis (Tunisia), Bahri is a soil scientist and agricultural engineer. She told us that: "If water issues are not properly addressed, Africa will continue to be years away from meeting its development targets." The problem is not necessarily one of scarcity, Bahri is quick to add, "it is also a matter of poor management."
Big cities top the list in this regard. At present, cities occupy less than 1% of most countries’ land area, yet they account for 5-20% of the water used, and this percentage can only increase. Since 2010, 11 African cities have populations above 5 million, and some 720 others have populations greater than 100,000. Without proper management, today's acute situation will turn into tomorrow's emergency.
"We urgently need to revisit conventional urban water management, which is typically based on actions conceived as isolated services, without any kind of overview,” says Bahri. She argues that we must ensure that high quality water is used solely for drinking and culinary purposes, otherwise this precious resource will become even more scarce. Wastewater and sludge (but also surface water, groundwater and stormwater), on the other hand, need to be properly treated, according to their final destination.
"Wastewater management poses both technical, planning, management, institutional, economic and policy challenges, and requires strong leadership,” says Bahri. “Wastewater plants often do not function or are overloaded, and the effluent is not suitable for irrigation.” In Ghana, for example, only 8 or 9 of the 44 wastewater treatment plants are in use, but unfortunately even these are well below technical standards. Faecal sludge treatment plants are in a bad condition too: as a consequence, more than 60% of excreta goes directly into the ocean.
"That's why we need to use a model of integrated urban water management, to address the problem within a consistent framework," Bahri insists. "This model would identify different water sources, consider their quality and attempt to allot each batch to a different usage." It's a model that links scientific expertise to political goodwill. "By doing so, storage, distribution and treatment, recycling, and eventually water disposal become components of a more globally conceived management process."
One virtuous example of wastewater reuse comes from Tunisia: industries pre-treat their effluents before discharging them into the sewer system and then up to 40% of the treated municipal wastewater is recycled for agricultural and landscape irrigation. Some countries,such as South Africa and Namibia have adopted successful wastewater treatment and management techniques. However, elsewhere in Africa, and especially in sub-Saharan Africa, the situation is far from acceptable: just 1% of wastewater is treated.
"Governments must be committed to water security both in mega-cities, as well as coastal and rural areas," Bahri observes. Disease outbreaks and the spread of contagious illnesses stemming from poorly treated wastewater are common. The impact of providing clean water at all points along the chain can set in motion a flywheel effect: safe water means less disease, a healthier population means better yields from agriculture, which in turn provides more food for humans, and more fodder for livestock. Better water management can also have a direct impact on the quality of life for girls and women, who are traditionally involved in finding, fetching and carrying water.
Bahri's conclusion is clear: "We need to foster long-term planning, that looks beyond the immediate problems and paves the way for those sustainable solutions which will be the legacy we leave to future generations." For now, these aspirations might as well be written on water: but let's hope that because of initiatives like today's World Water Day, and continuing research into water management practices, such statements will be carved in the stone of actual policies and practices.
Dr. Akiça Bahri was selected as the 2009 recipient of the Prof. C.N.R. Rao Prize for Scientific Research. This prize was instituted in 2006 to honor distinguished scientists from Africa and Developing Countries, who have made outstanding contributions to science and technology. The prize was awarded to her in Durban, South Africa, on the occasion of the TWAS 20th General Meeting and 11th General Conference held from 20 to 23 October 2009.