WASH Case Studies

As a continuation of the previous presentation on Wash let’s now look at some concrete examples. The first is a toilet and a shower, which were built to be used in a construction site. It shows very nicely, how quickly and easily a toilet can be built. It has a proper toilet seat, it is flushed with a bucket, and it even has a small Biofil soak pit with a plastic basket.

An example from Zimbabwe for smaller VIP latrines and how they are built. First, a circular hole is dug and lined with bricks. On top of that is placed a prefabricated concrete slab, which was specifically made for this purpose. The second phase is the outer wall, which in this case is a permanent construction, made of fired bricks. The roof is usually very simple and consists of metal or straw. And this is what the finished structures look like.

An example with running water and flush toilets from Ghana. The sinks are mounted on the outer wall, to take up less space, but also to keep the area cleaner and better ventilated. Only the toilet stalls are enclosed. The position and construction of the septic tank are particularly interesting. It is a biofil tank, positioned between the two rows of toilets, so that each side can be connected directly to it with as few pipes as possible. This is what the construction looks like.

These are the foundations and the preparation of the tank’s floor. A very thin layer of concrete is poured directly onto the ground. The next photos show the construction of a soak pit, which is connected to the septic tank. Since the amount of water generated during flushing would be too large to drain under the toilet structure, the gray water is directed from the main chamber into the larger pit on the side, where it is filtered through various layers of sand and gravel.

The main chamber is built from cement blocks and all wastewater pipes lead into it. It has a closed bottom, as the gray water is directed into the other chamber. A ventilation pipe was somehow placed among everything, not like in the textbook, where it goes over the roof, but it somehow worked.

A similar example from another school project, but with a more typical construction of the Biofil soak pit. It is a simple toilet building, which at the time the photos were taken was not yet 100% completed. The boys enter from one side and the girls from the other. The roof structure is quite open, to allow for good ventilation. The septic tank is located at the back of the toilet building and is quite visible, as pipes come out of it.

Therefore, it is always good to think about how to hide them from view. In this example, it was planned to completely close this part in later construction phases, when the second toilet building is built. This is what the preparation of the foundation looks like, when various pipes are laid in the ground or in the wall. Everything must be prepared and already positioned, before starting to pour the concrete. The walls of various toilet facilities, especially when there is running water, are almost always made of cement blocks or burnt bricks.

Materials that do not have high water permeability. Any type of clay construction is generally not the best idea in these situations. The construction of the biofiltration sewage system. Similar to the last example, with the difference that the bottom of the pit is left open. It is very common for this type of tank to be only half buried in the ground. This is possible because usually they are smaller and do not take up much space. Additionally, it is much easier to connect pipes and to open and empty the tank later. All pipes are directly connected.

As can be seen, this is not very aesthetic, but it is simple, and if something breaks, it can be easily repaired. The other smaller underground tanks are soak pits, which collect water from the urinals or sinks, so that they do not overload the septic tank. The pipes are simply laid in the sand-cement walls and then everything is plastered or covered with tiles, which is very important in order to keep the toilets clean.

Here is a project, that was carried out in partnership between DESWOS and the Center for Community Organization and Development from Malawi. It was a larger project, that included various parts and one of them was the construction of about 700 separating toilets for households in a rural area, which is predominantly inhabited by farmers. Of course, an additional part of the project was the training of users, without which it would not have worked. As can be seen in the photos and plans, these are very simple buildings with a clear design that perfectly fulfill their purpose. Moreover, each building cost only 300 euros – a small amount that has significantly improved the sanitary conditions of the people who use it.

Additionally, they provide an alternative way of value creation by transforming feces and urine into fertilizer. This is a typical separating toilet with two chambers that are mounted above the ground, so that the chambers can be easily emptied. A very useful addition to this construction is a small shower room on the side. Yes, it is a bucket shower, since there is no running water, but a very useful space for privacy and a simple way to provide a quick shower.

Here is the lower part, where you can see the three small vaults for collecting feces or urine. In the cross-section, you can see that everything was made with bricks and a small amount of screed. Everything is very simple and logical. This is the back with the two chambers, which are opened and emptied at intervals.

The interior looks similar to all previous examples for the toilet with two holes in the floor, which are used alternately, – usually every 6 to 12 months depending on usage – and a simple shower area in another room. As you can see, the walls and floors are not tiled, in order to keep costs low. That is something that can always be easily added, if the budget allows. And yes, maybe larger windows in the toilets – to let more air in – or a rain gutter and a simple way to collect rainwater from the roof, would have been nice additions. But even without that, this project is a perfect example of how a great impact can be achieved with little money: 300 euros for a small toilet building, which also includes a shower. It is inspiring to see projects that create something like this.

Continuing on the same topic. Another very effective and simple separating toilet project by Engineers Without Borders in Sierra Leone, which they did together with the local organization MADAM, that is Mankind’s Activities for Development Accreditation Movement. In this specific region, one of the challenges was that the groundwater level is very high during the rainy season, which leads to contamination of the wells. Therefore, a typical separating toilet was a good solution, since the storage tanks are above ground.

It is a very characteristic structure with two toilets that form a unit. Everything under one roof that collects rainwater, which is stored in a water tank and can be used for handwashing. Here is a brief overview of what the original design looked like. First the base slab, then the walls – which form different chambers – and the stairs. On top, there is another slab, which will form the floor of the toilets with all the necessary holes. The upper structure made of wood and plywood was later replaced by a classic construction with cement blocks.

And the finished design. You can see that the planning is more technical and somewhat more complicated than in the previous example. More parts are made of concrete, a thick foundation slab, which takes on the role of the foundation, as well as the upper toilet slab with all the prefabricated parts of the toilet itself. Prefabricated parts were even produced on-site, to be used as floor urinals, with ceramic tiles used as permanent formwork.

All walls are built with cement blocks and the roof is a simple wooden structure. The red doors close off the chambers, where the feces are to be stored. Some small details: an additional urinal for men was built inside, as an alternative to the squat toilet. In the middle photo, you can see the plastic containers, in which the urine is stored and you can notice, how simple the connection is. And the last photo shows the interior with the classic two holes and a middle part for urinating.

An additional element is the washing area on the side. Water from the water tank is used for this. In the outdoor area, special compost containers have been set up. It is a much safer procedure to handle the dried excrement. Thus, the vaults are emptied after about six months of use and then brought here for further composting. In these containers, ideally temperatures of about 60 to 70 degrees are reached, in order to kill most pathogens.

The following project for the Catholic secondary school Meki in Ethiopia, which was carried out with the support of Caritas Vorarlberg, takes all these previous concepts even further. It is a fairly large complex with a large number of schoolchildren and a great need for toilets. The available space on the property and the budget allowed for the implementation of the separation toilet system in a somewhat more advanced form, with special regard to the way the collection and composting takes place.

On the floor plan, the toilets and the washing area for girls are marked in red and for boys in blue. Their part also includes a large room just with urinals. What is made very clear is the separation between the publicly accessible area, where students can go, and the back area, which is accessible only to staff, who is responsible for the maintenance of the toilets. There are two separate outdoor areas, which are very pleasant to use, with many trees and plenty of shade.

Here you can see in detail how the toilet buildings are constructed. The raised base and the stalls are made of concrete- and cement blocks. Below are the storage areas for the feces boxes. The lightweight roof structure is made of bamboo and is covered with either metal or polycarbonate panels. All in all, it is a space, that is very well ventilated and has plenty of natural light. All of this can also be seen in the construction photos.

The substructure consists either of concrete for the supports, beams, stairs, and floor slabs or of cement blocks for the walls. Everything is a very logical choice for sanitary facilities, where there is a lot of water and moisture everywhere. On this conventionally built base, there is a more sustainable approach, where bamboo is used as a supporting material for the roof structure. Of course, the bamboo must always be raised above the ground to protect it from moisture. The roof structure consists mostly of metal sheets and occasionally of transparent polycarbonate panels, which let light in from above.

And the photos of the completed project. Lots of shade, a very manageable space, where it is completely clear to users where everything is. A completely different environment is created than in the typical toilet facilities of this size, one that is inviting for the users. All toilet stalls are always elevated, due to the collection technology. For each group, boys and girls, there is a large, covered area with running water, which is used for handwashing.

As discussed in our other wash video, it is crucial for the success of such projects to teach the users, in this case the students, how to properly utilize these new toilets that they are not used to. This is even more important than the technical implementation itself. Each door has a very clear drawing and instructions. So the water for washing comes from a large barrel, picked up and then you enter the toilet. Each toilet has even more instructions inside, as well as a color-coded description for each hole in the toilet.

In the corner stands a bucket, which is filled with wood chips or other dry material. And this is how these ceramic toilets are actually set up, using a special shape, into which the liquid clay mixture is poured. The toilet differs somewhat from the others examples in this presentation, as this is not a two-chamber system, but rather a change container located under the hole. The feces go in the middle, the front part is for urine and the back part is for washing.

The containers are exchanged and taken to another location for composting. At the same time, the urine and the gray water from washing are directed through pipes to the other side and into the underground tank. The plastic pipes are laid in a simple manner under the floor slab, so that they can be easily maintained if necessary. At the back of the toilet complex, there is a large urine and gray water tank, which is accessible only to authorized personnel.

From this side, there is also access to the feces containers, which are located behind locked doors. As soon as the tank or the containers are full, both urine and feces are picked up with the help of forklifts, trucks, or cisterns. It is a very simple and clean process, which requires good organization as well as a clear plan for where the composting takes place and how the finished fertilizer should be used.

And the last example, also separating toilets, but in this case combined with urinals. It is a project by Dream Big Ghana in the Volta Region, which serves as school toilets. The special feature here is the installation of urinals, which in turn reduce the use of the existing toilets. As soon as you enter, the urinals are located and the handwashing area next to the door. With a ramp, one can then go up and enter three separating toilets. Great emphasis was placed on menstrual hygiene and a clean and safe environment for women was created.

It is a restroom facility that looks good and shows that a nice design can definitely have a big impact, what the future maintenance looks like and the perception of toilets as something dark and dirty changes. The urinals separated from the toilets, and not just for boys, but also for girls, are a great addition. The only complaint would be that there is no provision for urine collection. A simple handwashing facility is operated to promote handwashing hygiene.

Soil or wood chips are often used after each use of the toilets. The exterior view shows the back part, where the chambers are opened and emptied, as well as the ventilation pipes that lead outside. And finally, a view from above, showing this very simple and effective toilet facility, which combines toilets and urinals in one building. It is very clearly designed and offers plenty of space inside. The parts that need it, toilets and shelves, are covered and protected from rain, while everything else remains open. The rain and especially the sun help to keep everything clean and odor-free, particularly at the urinals.

Here is a little tour where you can see what the users themselves have to say about it. These are the ladies’ toilets. Here we have the handwashing facility and here we have a urinal with a door for privacy. Come, let me show you the main toilets. These are our toilets. We have two, but one is being used. You open it carefully, and it is clean. The container for hygiene products is here and the wood chips are here, even a cup for the wood chips. And we are satisfied with the use.