Mary Anyango, a 34-year-old resident of the Korogocho slums in Nairobi, works in a food processing company as a packer, earning 88 USD a month. After late hours at work, she returns to the 10 x 12 feet one-bedroom home that she shares with her husband and three children. The house sits on a compound with thirteen other units and between them, the 14 houses share a single pit latrine toilet made of iron sheet wall and a concrete floor. Mary’s family forms five out of the three billion people worldwide who use toilets from which waste is not safely contained or managed. One billion people do not have access to toilets at all and defecate in the open. Inadequate sanitation is a pressing global challenge, with gender, health and environmental implications – over sixty percent of sewage in the developing world is discharged untreated into the environment.
Many African cities aspiring to expand sewer access to counter the severe implications of poor sanitation encounter roadblocks. Cash-strapped municipalities are ill equipped to bear the hefty costs of building and maintaining the required infrastructure. Further, access to fresh water, a necessary resource for water and energy intensive centralized wastewater treatment plants, is typically limited.
A solution lies in on-site sanitation (sanitation not connected to the sewer), the most common type of sanitation used by urban populations in developing countries in the form of pit latrines, septic tanks, bucket systems. But such methods come with their own challenges related to safe removal, transport, and disposal of human waste. And there are still additional costs involved. The shallowness of the toilet in Mary’s compound makes it necessary for an evacuation every 3 months, which all households must pay for. In cities such as Lagos, the rainy season brings flooding and increases the frequency of evacuations required for toilets such as pit latrines, throwing many household budgets into disarray, or risks overflowing, causing health risks.
In the face of these obstacles, the Bill and Melinda Gates Foundation launched the Reinvented Toilet Challenge in 2011 to directly address this technology and product gap in on-site sanitation. Multiple institutions have engaged in designing on-site sanitation products for the urban poor that address the whole sanitation value chain – storage, emptying, transport, treatment and disposal/reuse of human waste. These are standalone systems that, in some instances, also convert human waste into safe by-products such as electricity, water, biogas and fertilizer.
To be able to adequately meet the challenge of sanitation, it is critical for the design and implementation of these systems to understand and account for consumer preferences. Our research within poor urban (tenement and informal settlement) communities in Kenya and Nigeria points to four lived realities that on-site sanitation providers need to consider before design, rolling out, and scaling their products globally:
Tailor the value proposition to the buyer: Although poor sanitation has a direct adverse impact on urban poor populations, many cash-strapped households do not view sanitation improvements as a priority over other needs. To compensate, the products need to be viewed as aspirational or have a clearly articulated value proposition. Across the cities we looked at in Kenya, the spend on electricity and cooking costs can vary by 50%-100% from neighborhood to neighborhood. In such a scenario, many poor urban households might look to an on-site sanitation solution as one that addresses their utilities problem. A solution that provides sufficient quantities of highly desired outputs such as biogas and electricity in a manner that also creates cost-savings for users is much likelier to be adopted.
Get the payment structure right: Many households live in a deeply entrenched “kidogo economy”, i.e., are only able to pay small amounts rather than large lump sums. This is reflected in the common habit of making daily purchases for fuel and water as opposed to bulk payments. Landlords are also reluctant to pay for upgrades to sanitation systems as they often charge “too-little rent” which often does not come regularly. To address this challenge, companies like Sanergy lease their toilets. Similarly, solar home system companies such as MKopa and Fenix International in Africa have developed pay-as-you-go business models. Apart from creating sufficient quantity of desirable by-products, on-site sanitation solutions need to take affordability into account.
Design toilets around space, terrain and utilities constraints: Installing individual toilets or even shared sanitation systems in some areas or buildings (whether existing or new) can be challenging. In tenements and informal settlements, shared toilets are often the only practical solution as there is no space to install a single toilet and piping in a one room household. In Lagos, some informal settlements are precariously situated on a lagoon and prone to flooding, limiting the opportunity to build on-ground sanitation systems. Toilets should also not depend on a user’s existing water supply as household members (often women) have to walk to collect water and water supply is intermittent. In our research in Lagos, none of the participants had water directly piped to their sanitation system, and they were responsible for collecting their water for toilet use. On-site sanitation solutions should be designed to take these very real constraints into consideration. Solutions that may well work in wealthier neighborhoods and/or cities, may not in poorer locations.
Plan for product maintenance: Users are reluctant to purchase products that require complicated and/or expensive maintenance. Most study participants said they would like to maintain a new sanitation system themselves to avoid the cost of hiring a plumber, an unaffordable expense to most households. If the product does need a plumber, it should be easy to service/fix using local informal plumbers and local spare parts. If it isn’t, the provider will need to invest in upskilling local plumbers. Any disposal that is required for the sanitation solution should also ideally be secured by the service provider. In the absence of this planning, users seem prepared to resort to unsanitary disposals (in rivers, etc.), making it crucial that these challenges are considered while the product is being designed, rather than as an after-thought and making sure there is a maintenance ecosystem in place to delivery these services.
Innovative, environmentally sustainable and cost-effective solutions are required to solve the global sanitation challenge. The global sanitation community is learning a lot about the preferences and requirements of the people who stand to be most impacted by these solutions and careful and continued consideration of these on-ground realities is required if we are to make a dent in the vastness of this problem.
For more information, please see the full study at http://stepsforsanitation.org. The report includes assessments of the sanitation ecosystem in Nigeria and Kenya, detailed profiles of end-users and their preferences, trade-offs around design features, and business-model consideration to make on-site sanitation work in both countries.
