Wastewater treatment
Published: 07 July, 2009
Commercially viable technologies are needed for the recycling and reuse of wastewater
Viewpoint
Dr Bindeshwar Pathak
The development and application of suitable technologies will be critical to extending adequate sanitation to much of sub-Saharan Africa’s growing urban population, according to Dr Bindeshwar Pathak, the founder of the Sulabh International Social Service Organisation in India and recipient of the 2009 Stockholm Water Prize for his work in the field of sanitation.
Founded in 1970, the Indian NGO specialises in the provision of lowcost sanitation facilities to India’s urban population and has developed various technologies designed specifically for the developing world. The cornerstone of these is the Sulabh Shauchalaya twin pit, pourflush toilet system, requiring just 1.5-2 litres of water to flush.
“A septic tank requires 10 litres minimum per flush, and a sewer system requires 20 litres. So just consider the enormous quantities that you can save if you use this technology,” says Mr Pathak.
Prices for the toilets start at $10 apiece, are not dependent on existing infrastructure and are designed to be built entirely from locally available materials. Mr Pathak says that more than 40m have been installed across India by Sulabh, other NGOs and the central and state governments.
“In total, 10m people use the toilets we have built so far daily. If you add the toilets that have been built by other agencies, and multiply them by an average of five persons per family, the number goes up to as many as 200m people.” The Shauchalaya toilet system has been declared a Global Best Practice by the United Nations, which recommends it for use by more than 2.6bn people around the world.
An important part of the urban water management landscape is the treatment and reuse of wastewater. Beyond the implications of effective wastewater management and treatment for public health, it may also be reused for purposes such as agriculture. Considering that 70 percent of all water that is used for human activity is devoted to irrigation, the potential of reused wastewater becomes apparent. In a region such as sub-Saharan Africa, where up to 22 countries are expected to experience water stress or scarcity by 2025, it becomes critical. Yet despite such potential, wastewater treatment levels are at almost negligible rates across the region.
Competing national priorities are one reason for this. “It doesn’t receive priority in the eyes of the politicians and policy makers in country due to competing priorities,” says Colin Sabol, vice president of Marketing and Business Development at ITT Corporation.
“When you look at treating wastewater and putting a sanitation system in place, and you compare it to some of the other needs that are sitting before you, such as security and food security and high profile medical issues such as HIV/Aids, they tend to get priority over wastewater.”
This is compounded by a lack of appropriate technologies, he adds. “Because the companies that manufacture wastewater treatment technologies serve the developed markets,theyhaveproductsthatarealignedfor those markets and economies that can afford them. So the products don’t match the local market needs.”
