• 663 million people still lack improved drinking water sources. 4
• By 2050, close to 70 % of the world’ s population will live in cities, compared to 50 % today 5. Currently, most cities in developing countries do not have adequate infrastructure and resources to address wastewater management in an efficient and sustainable way.
• The opportunities from exploiting wastewater as a resource are enormous. Safely managed wastewater is an affordable and sustainable source of water, energy, nutrients and other recoverable materials.
TOP LINE MESSAGES
• Globally, over 80 % of the wastewater generated by society flows back into the ecosystem without being treated or reused. 1
• 1.8 billion people use a source of drinking water contaminated with faeces 2, putting them at risk of contracting cholera, dysentery, typhoid and polio. Unsafe water, poor sanitation and hygiene cause around 842,000 deaths each year. 3
• The costs of wastewater management are greatly outweighed by the benefits to human health, economic development and environmental sustainability – providing new business opportunities and creating more‘ green’ jobs.
WASTEWATER AND THE WATER CYCLE
Water has to be carefully managed during every part of the water cycle: from fresh water abstraction, pre-treatment, distribution, use, collection and post-treatment, to the use of treated wastewater and its ultimate return to the environment, ready to be abstracted to start the cycle again.
1 On average, high-income countries treat about 70 % of the wastewater they generate, while that ratio drops to 38 % in upper-middle-income countries and to 28 % in lower-middle-income countries. In low-income countries, only 8 % of industrial and municipal wastewater undergoes treatment of any kind( Sato et. al, 2013).
2 WHO / UNICEF( 2014), Progress on drinking water and sanitation: 2014 update: https:// www. unicef. org / gambia / Progress _ on _ drinking _ water _ and _ sanitation _ 2014 _ update. pdf
3 WHO( 2014), Preventing diarrhoea through better water, sanitation and hygiene: exposures and impacts in low- and middle-income countries: http:// apps. who. int / iris / bitstream / 10665 / 150112 / 1 / 9789241564823 _ eng. pdf
4 WHO / UNICEF( 2015) Progress on sanitation and drinking water, 2015 Update and MDG Assessment https:// www. wssinfo. org / fileadmin / user _ upload / resources / JMP-Update-report-2015 _ English. pdf
5 UN Department of Economic and Social Affairs( 2014), World Urbanization Prospects: 2014: https:// esa. un. org / unpd / wup / Publications / Files / WUP2014-Highlights. pdf
14 Africa Water, Sanitation & Hygiene • March- April 2017