"Global Overview of Experiences with Sustainable Sanitation" Anthony Kilbride, Independent Consultant
This is a review of one presentation from the Sustainable Sanitation Conference, co-hosted by SOIL and UNICEF in June 2012. For an introduction and general overview of the conference, or to find information about other presentations, click here.
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Global Overview of Sustainable Sanitation Experiences
Anthony Kilbride, an independent consultant, gave an overview of sustainable sanitation in other parts of the world. Anthony started by giving the conference a perspective on sanitation history, highlighting 3 key dates; (1) 1860 – the adoption of the WC (water closet) by Queen Victoria, effectively making sanitation synonymous with waterborne sanitation for much of the world’s population. (2) 1913 – the Haber-Bosch process, and the agricultural revolution afforded by artificial Nitrogen fixation. (3) 2012 – the Sustainable Sanitation Conference in Port-au-Prince.
Anthony then gave the Sustainable Sanitation Alliance’s definition of sustainable sanitation and explained how re-use of treated human waste varies widely around the world. Anthony gave some examples of innovative waste managing practices in the e-Thekwini municipality of South Africa; a large UDT project (including a discourse on ventilation pipes); drying and pelletizing of latrine sludge; and agroforestry.
Finally, the presentation closed with a statement on the logistical and energy demands on the transportation of human wastes, by truck or by pipe, and the relevancy of decentralized waste treatment options for Haiti.
Apèsi Jeneral Eksperyans sou Sanitasyon Dirab
Anthony Kilbride, yon konsiltan endepandan, bay yon apèsi sou kòman Sanitasyon Dirab ye nan lòt kote nan monn nan. Anthony kòmanse ak yon ti istorik soujan sanitasyon, kòmanse lèl mete aksan sou 3 dat enpòtan; (1) 1860 – Rèn Viktorya adopte WC (water closet = twalet flush) nan dat saa, yo te kòmanse yon sanitasyon efikas sa kite vle di maladi moun trape nan dlo pou anpil nan popilasyon kak viv nan monn nan. (2) 1913 – Pwosesis Haber-Bosch la, ansanm ak revolisyon agrikòl kite rive posib gras ak fiksasyon atifisyèl azòt. (3) 2012 – Konferans sou Sanitasyon Dirab nan Pòtoprens
Apre sa Anthony eksplike jan Alyans Sanitasyon Dirab (SuSanA, ang) defini Sanitasyon Dirab epi eksplike kòman trètman kaka moun varye anpil nan lemonn antye. Anthony bay kèk egzanp sou inovasyon nan pratik jesyon kaka yo fè nan minisipalite eThekwini nan peyi Afrik di Sid; yon gwo pwojè UDT (ki gen ladann yon gwo diskou sou vantilasyon nan tiyo yo); sechaj ak debouraj labou nan latrin; aplikasyon agrikilti pou fè forè.
Prezantasyon an fini ak yon fraz sou ekzijans enèji nan transpò kaka, kit se nan kamyon osinon nan tiyo, epi enpòtans opsyon trètman kaka desantralize pou Ayiti.
Aperçu Global d’Expériences en Assainissement Durable
Anthony Kilbride, un consultant indépendant, a donné un aperçu de l’assainissement durable dans d’autres parties du monde. Anthony commença par un bref historique sur l’assainissement, soulignant 3 dates importantes; (1) 1860 –l’adoption du WC (water closet) par la reine Victoria, rendant l’assainissement effectif ce qui fut synonyme de eau usées pour une grande partie de la population mondiale. (2) 1913 – Le processus de Haber-Bosch, et la révolution agricole rendue possible grâce à la fixation artificielle de l’azote. (3) 2012 –La Conférence sur l’assainissement Durable à Port-au-Prince.
Anthony a continué avec la définition du SuSanA (Sustainable Sanitation Alliance) pour assainissement durable et a expliqué comment la réutilisation des excréments humains varient largement à travers le monde. Anthony a cité en exemple quelques pratiques innovatrices en matière de gestion des déchets en application dans la municipalité de eThekwini en Afrique du Sud; un grand projet de UDT (avec un discours sur les tuyaux de ventilations); le séchage et la vidange des boues de latrines; et l’agroforesterie.
La présentation se conclut avec une phrase sur la logistique et les exigences en énergies que nécessitent le transport d’excrément humain, par camion ou tuyauterie, et la nécessité de décentraliser les options de traitement des excrétas en Haïti.
My presentation, on ‘The Global Overview of Experiences with Sustainable Sanitation’ is probably somewhat ambitious to fit into a 30 minute period, however, I will try and tie all the parts together. The parts of this presentation are broadly speaking:
- Sustainable Sanitation – a little history.
- Treatment systems in Port-au-Prince – a little evaluation, are they sustainable?
- Sanitation in South Africa – a little description.
- Sustainable Sanitation in Haiti – considerations for the future.
(The presentation focuses on urban and peri-urban areas. )
When I talk about ‘Sustainable Sanitation’, what do I mean? Well, I think it depends upon your perspective. I think one of the objectives of this conference is to develop our perspectives, to share our perspectives, and work towards finding a common, shared perspective for Haiti.
So, we need to share our perspectives. And I will start by sharing my perspective on the history of sustainable sanitation in Haiti. I see it defined with 3 events….
The first event is the adoption of the WC by Queen Victoria, in her palace in Germany, in 1860.
Nearly a hundred years before this, the first WC was designed and installed for another English Queen, Queen Elizabeth I, in 1596.
Between these 2 dates, and especially in the late 17th century, there was a great period of toilet design, including the earth closet, pan closet, and water closet.
Because Queen Victoria was the celebrity of her day. When she started using a WC, people took notice, and people followed.
(Imagine today, what would happen if famous celebrities used a composting toilet. People often follow celebrities when it comes to adopting new technologies)
One effect of the advent of the WC was that the industry of ‘Nightsoil’ merchants, or those who emptied privies manually, became redundant, and was replaced by…
.. Pipes, and sewerage.
Because of the WC, the word ‘sanitation’, for those who are fortunate to have access to sanitation, is synonymous with waterborne sewage.
However, only 5-10% of wastewaters in the world are treated before they are discharged into the environment.
The second event is the successful demonstration of the Haber-Bosch process, which fixed Nitrogen from the atmosphere.
The photograph is of Fritz Haber.
The Haber-Bosch process gave mankind enough Nitrogen to grow more food than needed. I.e. The Haber-Bosch process gave man the potential to satisfy his greed.
Today, industrial agriculture produces so much food, that much of it is wasted.
Because the H-B process requires a lot of energy, as man has become addicted to artificially produced Nitrogen, he has become addicted to energy and fossil fuels.
With the growing demand on natural resources, land, and power, comes the negative effects of globalisation…
… famine, desertification, war.
So, we can see that a toilet, changed the way we think about our most natural resource – poop. And that in turn affected our approach to agriculture. And that has contributed to a divided, unequal world.
So we can see that a toilet is not only important but also influential to the way we live.
The final event in Anthony’s brief history of sustainable sanitation in Haiti is…
… right here, right now.
Haiti, and countries like Haiti, are the best possible examples to show to the world, how sustainable sanitation can make; not a small difference, but a huge difference.
Sustainable sanitation in Haiti can help to break the cycle of struggle, poverty, and disaster. And just as Haiti showed the last world of a life free from political oppression, Haiti today can show the world of a life free from environmental oppression: Through innovative sustainable sanitation technologies and practice.
The waste treatment facilities that exist in Port-au-Prince today are:
- SOIL compost site at Troutier.
- DINEPA Waste Stabilisation Ponds at Morne Cabrit.
- DINEPA Waste Stabilisation Ponds at Titanyen.
The question in light of this conference has to be; are these treatment practices sustainable? Who decides whether they are sustainable or not?, and how do you decide?
One available definition of sustainability comes from SuSana.org.
In light of this definiton, with its 5 criteria, how do we assess waste treatment in Port-au-Prince?
Ultimately, as I said before, it is a matter of perspective, and nuanced perspectives require nuanced solutions.
This slide has information from a number of sources, and could be contested. The aim of the table is to show that re-use of human wastes is occurring around the world, but it varies wildly.
The relevancy of re-use of human waste is dependent upon macro- and micro- factors, and on your perspective.
Now I would like to share some experiences from a research visit to South Africa, where I witnessed some interesting sustainable sanitation projects.
This is downtown Durban, beautiful blue seas with big waves and a few sharks.
This is peri-urban and rural eThekwini, Durban’s municipality.
When in Durban, this coastal city, with its hot and humid summers, reminded me of Haiti. And when you look deeper under the surface, there are in fact many similarities between eThekwini and Port-au-Prince.
Why is Durban, South Africa a relevant case study?
- There are clear similarities in topography between Durban and Port-au-Prince including the coast and the hills.
- Similar populations.
- Similar socio-economic conditions for parts of the population.
- Similar political histories.
- Similar inequality.
- After the 2010 earthquake, Port-au-Prince has one of the largest peri-urban areas in the Caribbean in the form of Corail, Croix-de-Bouquets, Titanyen.
- Similar sanitation problems.
- Similar health problems.
- Free services are required by the new democratic constitution drafted in 1996. In Haiti there is no culture of paying for sanitation services, e.g. NGO projects.
For all the similarities, it should be noted that Haiti is much worse off. For example South Africa has a mortality rate of 57/1000. Haiti’s is 3 times that at 165/1000.
The first project I visited was a UDT (Urine Diversion) project. UDTs were chosen for large-scale implementation because of their financial feasibility, technical feasibility, and public health benefits if people used them.
75,000 toilets were built in 4 years, or approximately 1,500 toilets/month. The cost of each toilet was about 750USD per toilet. This is economical compared to Haiti’s UDTs which range between 1000USD and 1500USD per unit.
The project has been criticized for low community participation, and final research on user acceptance will be published in 2012. People’s first choice was to have flush toilets, but these could not be provided for free by the municipality because the connection costs would be too high.
The main driver for the project was public health, to prevent cholera and other water-borne diseases.
Local enterprises were set up and trained to empty toilets at a cost of approx. 10USD per chamber.
I thought the toilets were good for many reasons: A good design. Easily access to the rear of the vaults and easy transfer of UDT seat. A urinal for men discourages them from peeing into the toilet, which wets the chamber below and causes odour and attracts flies. The toilet I visited did not smell.
The toilets also had good ventilation because the air was allowed to pass over the top of the pipes, creating the convection current to draw up smells. The vent pipes were covered with a ‘hat’ to prevent water entering in.
Ventilation is usually neglected in toilet design…
These 3 toilet ventilation pipes are faulty and will not provide good ventilation. Can you see why?
EWS inherited a huge backlog of sanitation needs, and had to come up with answers fast. They had an enormous task ahead of them, including the need to empty 40,000 latrines…. So what would you do? And what questions would you ask?
- 1latrine: How would you do it? would you need help? would you need a vehicle?
- 10 latrines: Could a sludge truck do it? Would they burn? Could I just ignore them?
- 100 latrines: Are there professional services already available?
- 1000 latrines: Are the workers protected? What dangers do they face? Is ascaris still present in the sludge?
- 10000 latrines: Where do we deposit the sludge? Who will pay for it?
All these questions and many more were asked by EWS. They researched many different practices and tested them out.
The first question was how to empty the pits. After trying every different kind of mechanical equipment available, the best method decided upon was a spade. The treatment options considered were:
- Treat in situ with enzymes – didn’t work, need liquid in the first place.
- Discharge to the WwTP – sludge too high a concentration (700 times more concentrated than raw sewage)
- Anaerobic digestion – still too high a concentration.
It is these last 2 options that will now be presented.
The poop pelletizer is a patented technology which bakes solid latrine sludge under very high temperatures. The sludge is loaded into the pelletizer using a bobcat…
… The sludge is pelletized in a screw auger. The pellets drop out onto a conveyor belt which is heated….
… the remaining solid waste in with the latrine sludge is ejected at the end of the screw auger…
… and buried in a landfill.
The poop pellets are heated to kill all the pathogens
… and can be used as fertilizer.
The poop pelletizer required a lot of energy to heat the pellets. And a lot of high-end technology… so, is it sustainable?
If Haiti can’t afford a pelletizer and doesn’t have a cheap and readily available energy source to power the pelletizer, then what can Haiti do with its latrine waste?
Well, a more sustainable option is shown in the photo. Here, EWS staff are emptying latrine sludge into a pit…
…in which are planted trees. Trees are our natural cleansers and providers of our oxygen, our water, our forests and ecosystems. ‘ The answer lies in the soil.’
Now, back to Port-au-Prince…
Let us consider again the option for disposal and treatment of wastes at Titanyen and Morne Cabrit: Waste Stabilisation Ponds, or WSPs.
Using some assumptive mathematics… If we assume all of Port-au-Prince’s 3,000,000 population use WSPs… and these have the same process dimensions as the existing WSPs… then we will need to construct 1,257 Stadium sized WSPs in the Metropolitan Region.
But how does the waste get there. Now we have to consider the need for transportation…
3 transportation options currently exist in Port-au-Prince:
- trucking raw sewage
- trucking dry poop
The problem with all 3 transportation options is that they require energy. If we can redesign the logistical framework of transporting wastes, then we can provide ourselves with a more diverse array of options.
A 4th option is to decentralize waste treatment.
DEWATS means decentralised wastewater treatment system. It is more of an approach than a technology, and it can apply to wastewater and compost.
The slide shows an example of a DEWATS system. There are 2 concepts to focus on. 1) The treatment system is modular, because treatment of wastewater usually requires different intensities of treatment 2) Post-treatment is essential if effluent release is in an urban area, like Port-au-Prince.
Here is an example of a DEWATS system that was installed in ethekwini/Durban, in South Africa, in 2010. For 86 households.
2 small technical notes:
- it has a small footprint.
- the constructed wetland is delineated from the surrounding area; it is a contained treatment unit and it is monitored and evaluated as such.
The key to the success of these diverse sanitation projects in eThekwini is Research & Development. For this reason, EWS forged an alliance with the University of KwaZulu-Natal, who research active EWS projects.