In the developing world, the business of sanitation is rarely considered to be a money maker. However, new developments in the productive use of human waste are opening up real opportunities for cashing in on urban wastewater and sludge. Research carried out by the International Water Management Institute (IWMI) is attempting to establish where and how such models can be made socially or commercially viable.
Walk through almost any city in the developing world and it is hard not to see how almost every area of open water is little more than a trash-filled sewer. There is a desperate need for investment in better sanitation, but cash-strapped city authorities struggle to meet the challenge. However, what if the human waste that is polluting urban water systems could be used to make money? Then, perhaps, businessmen might take an interest, bringing private sector know-how and resources into partnerships with public providers.
In many cities, small-scale entrepreneurs are already using human waste to make a profit. In Ghana, for instance, urban and peri-urban farmers use nutrient-rich sludge and wastewater to grow spectacular crops. Other pioneers are using human waste to make compost, for aquaculture and for generating biogas. Careful attention needs to be paid to health concerns and marketing goods produced using waste or wastewater can be a challenge. Nevertheless, where these concerns can be addressed, scaling-up often becomes a viable option. However, how could a city authority or a private investor be sure that any proposed scheme might work? That is the question that IWMI and partners tried to answer in a recently published paper, Efficiency indicators for waste-based business models: Fostering private sector participation in wastewater and fecal sludge management, which was published in the journal, Water International.
Taking a broad view
The authors of this article, led by Ashley Murray, a social entrepreneur, and recent awardee of National Geographic, are suggesting efficiency indicators to help policymakers and the private sector decide which reuse or recycling approach could be right for them. Many factors need to be taken into account to develop reliable indicators. For instance, planners need to know if there are enough end-users for a waste product. After all, the production of human waste never stops. Operators need to be sure that there will be enough demand to accept a continuous supply of waste products to avoid a backlog of unpleasant and unhealthy waste.
"Choosing which approach to take will undoubtedly vary with local conditions," says IWMI’s Pay Drechsel, one of the paper’s authors. "The amount of land available, for instance, is critical. Let’s say you have a town of 100,000 people. If you are thinking of using waste to fertilize crops you need to know how much land area is available to accept the waste. To absorb the produced urine, for instance, you need 5-10 times the area as that of wastewater-fed aquaculture or irrigation with wastewater-fed stream water."
Similarly, with household generated biogas, the researchers worked out how many users would be needed to turn a profit.
Job creation and better sanitation
If human waste can be harnessed for commercial gain, the possible benefits are huge. Sanitation could be improved, new businesses started and urban agriculture for poor farmers enhanced.
"Our primary goal is to present these indicators as a possible tool to identify opportunities for business-oriented reuse systems. The hope is that these can then help finance and incentivise adequate sanitation," says Drechsel. "There is huge potential here to create jobs and improve public health, but many hurdles still need to be overcome. Through this research we now believe this can work at scale and want to inspire entrepreneurs and decision makers to think the same"
IWMI’s next step is to look at dozens of real-life cases across the globe to test the efficiency indicators in field conditions.
The paper appears in a special IWMI edition of Water International, Wastewater use in agriculture: Economics risks and opportunities.