(Previous: From Coca-Cola to A Better Sanitation #2)
Look beyond sanitation problem.
If we can learn lessons from the innovators in every sector, then in the future we make together, that happiness can be just as ubiquitous as Coca-Cola. Here are some innovators who talk about ideas to solve sanitation problem.
FRANCIS DE LOS REYES, Environmental Engineer and Sanitation Activist
Sanitation is a basic human right.
At TED Fellows Retreat 2013, he said that we’ve got to rethinking sanitation and we’ve got to reinvent the sanitation infrastructure, and he’s going to argue that to do this, we have to employ systems thinking. We have to look at sanitation chain. We start with human interface, and then we have to think about how feces are collected and stored, transported, treated, and reused – and not just disposal but reuse.
He found that municipalities and cities build sanitation infrastructure to avoid open defecation, for example, like pit latrines, in peri-urban and rural areas. He gave example in KwaZulu-Natal province in South Africa, they’ve built tens of thousands of these pit latrines. But there’s a problem when you scale up to tens of thousands. The problem is what happens when the pits full? This is what happens: people defecate around the toilet. In schools, children defecate on the floors and then leave a trail outside the building and start defecating around the building, and these pits have to be cleaned and manually emptied. And who does the emptying? Workers who have to sometimes go down into the pits and manually remove the contents. It’s a dirty and dangerous business.
To solve the pit emptying, he talked about a urine-diverting toilet, there’s two holes in this toilet. The front and the back. The front collects the urine and the back collects the fecal material. And what are we doing separating the urine? It has 80 percent of the nitrogen and 50 percent of the phosphorus, and can be treated and precipitated to form things like struvite, which is a high-value fertilizer, and then the fecal material can then be disinfected and again converted to high-value end products. He also gave example of his research that we can reuse the water by treating it in on-site sanitation systems like planter boxes or constructed wetlands. So, we can open up all these possibilities if we take away the old paradigm of flush toilets and treatment plants.
So you might be asking, who’s going to pay? Well, at the talk, he was going to argue that governments should fund sanitation infrastructure. NGOs and donor organizations, they can do their best, but it’s not going to be enough. Governments should fund sanitation the same way the fund roads and schools and hospitals and other infrastructure like bridges, because we know, the WHO has done this study, that for every dollar that we invest in sanitation infrastructure, we get something like three to 34 dollars back.
Students from North Carolina State University come up with a more simple solution about pit emptying. A simple, modified screw auger that can move the waste up from the pit and into a collecting drum, so that the pit worker doesn’t have to go down into the pit. They tested it in South Africa, and it works. This idea is hoped to extend the life of pits so that we don’t have to resort to quick solutions that don’t really make sense.
JOE MADIATH, Social Entrepreneur
Better toilets, better life.
He was talking about his project as TEDGlobal 2014. The project is purposed to avoid open defecation in India. Seventy percent of India defecates in the open. And if you look at the world total, 60 percent of all the crap that is thrown into the open is by Indians.
He, together with a lot of villages, began to talk about how to really address the situation of sanitation. And they came together and formed a project called MANTRA (Movement and Action Network for Transformation of Rural Areas). Villages that agree to implement this project, they organize a legal society where the general body consists of all members who elect a group of men and women who implement the project and, later on, who look after the operation and maintenance. They decide to build a toilet and a shower room. And from a protected water source, water will be brought to an elevated water reservoir and piped to all households through three taps: one in the toilet, one in the shower, one in the kitchen, 24 hours a day. The pity is that their cities, like New Delhi and Bombay, do not have a 24-hour water supply. But in these villages they want to have it.
So, these people, without a single exception of a family in a village, decide to build a toilet, a bathing room. And for that, they come together, collect all the local materials – local materials like rubble, sand, aggregates, usually a government subsidy is available to meet at least part of the cost of external materials like cement, steel, toilet commode. And they build a toilet and a bathing room. Also, all the unskilled laborers, that is daily wage earners, mostly landless, are given an opportunity to be trained as masons and plumbers. So while these people are being trained, others are collecting the materials. And when both are ready, they build a toilet, a shower room, and of course also a water tower, an elevated water reservoir. They use a system of two leach pits to treat the waste. From the toilet, the muck comes into the first leach pit. And when it is full, it is blocked and it can go to the next. But they discovered that if you plant banana trees, papaya trees on the periphery of these leach pits, they grow very well because they suck up all the nutrients and you get very tasty bananas and papayas.
It is always a 24-hour water supply because water gets polluted very often when they store it – a child dips his or her hand into it, something falls into it. So no water is stored. It’s always on tap. This is how an elevated water reservoir is constructed. And that is the end product. Because it has to go high, and there is some space available, two or three rooms are made under the water tower, which are used by the village for different committee meetings.
I think Madiath’s idea is great. Educating people how to maintain toilets and together build the toilets. I’m just going to give opinion, the education given to the village is not only how to maintain the toilets but also how to use the toilets properly and a healthy lifestyle, like washing hands, brushing teeth, as well as cleaning the toilets.
SARAH CARINS-SMITH, HALEY HILL, EMMANUEL NAZARENKO, The Boston Consulting Group
Sanitation solutions for urban growth.
In a working paper, published by The Boston Consulting Group (BCG), they argue that a long-term provision of sanitation is required. Part of the problem is that the benefits of adequate sanitation aren’t readily apparent, and citizens often value other products and services more. Additionally for the governments prioritizing sanitation efforts, the costs are daunting. Urban planners have typically focused on traditional sewage systems with flush toilets – the “gold standard” of sanitation – because they limit exposure to waste matter and carry minimal risk of environmental contamination when properly built and maintained. But sewage systems aren’t always a cost effective solution for the developing world.
Besides requiring an extensive infrastructure, lots of water, and high up-front and maintenance costs for governments, sewage systems can take many years to build, are far more expensive than other options, such as on-site septic tank, and can’t achieve scale as quickly to address the large populations in need. Cities should therefore determine whether an emphasis on conventional sewage systems is right for their situations.
The basic technologies defined for different urban sanitation options have not changed significantly in the past several decades and relatively few potential solutions have been used at scale. Four of these represent the dominant set of urban sanitation solutions used today:
- Centralized Conventional Sewer-based Systems – designed to rapidly transport large volumes of human waste using a network of pipes from large areas of dense human habitation to centralized wastewater treatment plants (WWTPs), where the water and waste can be treated before being discharged back into the environment. They require relatively high water availability to function effectively.
- Decentralized Simplified Sewer-based systems – designed to serve smaller neighborhood-sized areas. They use shallowly buried, smaller diameter pipes than conventional sewers as well as smaller WWTPs. These systems have seen significant application in Latin America, especially in Brazil where these are referred to as “condominial sewers”.
- On-site Septic Tanks – designed to be used by a single household or shared among small numbers of households. The septic tank is meant to allow for setting of solids and treatment of the effluent, which is usually allowed to leach into the ground using a leach field or a soak-away. The solids collected in the tank must be pumped out when the tank fills up and ideally treated at a fecal-sludge treatment plant. When properly designed and regularly de-sludged, septic tanks are relatively low-cost solution with limited environmental impact. The two main challenges are ensuring that the removed sludge is properly treated and not simply discharged into the environment and leaching safety where population densities are high.
- On-site Pit Latrines – latrines (dry and pour flush) consist of a hole dug in the ground below a toilet superstructure. In many countries, latrines are the predominant rural sanitation option; however they are still used in urban areas as well due to their overall simplicity and low cost. Latrine pits are usually unlined and can leach significant quantities of nitrogenous compounds and pathogens into the soil, potentially contaminating groundwater. The risk of groundwater contamination is significantly worse for latrines than it is for septic tanks. As a result, latrines are unlikely to be a sustainable, long-term sanitation solution in urban areas given the density of inhabitants, especially in those areas that use groundwater for drinking.
- Other Options – a number of other sanitation options such as Ecosan/Composing toilets and Urine Diverting Dry Toilets (UDDT) are sometimes mentioned as potential large-scale solutions especially when these are coupled with innovative, collection-based business models. Such solutions can be an attractive option as they do not require water (and, in fact, discourage the use of water), can be low cost, and enable recovery of nutrients for reuse. A significant number of these toilets exist in rural and peri-urban areas across many countries. However, these options have not yet been demonstrated to be effective on a large scale for densely populated urban applications, though work is underway to do so. There is also a delicate balance in maintaining these business models which often rely on resource recovery (such as fertilizer generation) schemes to help offset the cost of collecting the waste. As yet, it is unclear if these collection schemes can be self-sustaining.
In this study, they focus their analysis on the three sanitation options that are currently best placed for large-scale urban implementation. Centralized Sewers, Simplified Sewers, and Septic Tank-based On-site Sanitation. A simple framework to indicate how an increase in the value of specific local variables affects the relative attractiveness of different sanitation options (all other factors being equal, an increase in population density makes centralized sewer systems more attractive, while higher uncertainty about future growth pushes the needle in favor of decentralized and on-site systems).