How to build a toilet for less than a few thousand rupees or twenty dollars – and stop open defecation

The Septic Drain

Those who live in developed countries may be surprised to learn that a large part of the human population lives without a toilet. Put crudely they simply piss and shit out in the open. In India it is estimated that half the population does that. This is all the more tragic in a country that invented toilets, bathrooms and covered drains five thousand years ago in the Indus Valley civilization (http://alienaccount.blogspot.in/2013/09/indus-valley-and-atlantis.html). Since then though, a lot of piss and water has passed under the bridge with a slide into poverty and decay.

Aside from the inconvenience of having to run out into the fields every now and then, the phenomenon of open defecation poses some serious issues that have only increased with an increase of population density on the planet. First are health issues. When it rains the waste is washed into drains, rivulets, rivers, ponds and lakes. Water sources are then charged with disease causing bacteria that make their way into humans and animals sooner rather than later. A second even more serious issue has emerged in recent times because of a lack of law and order. Women and girls venturing out have been caught and raped by disgusting vile animals hiding in human bodies, some even killed in an attempt to hide evidence. Such incidents have been highlighted in the media and need not be repeated here. The solution to the problem is simply constructing a toilet at home. A major impediment to this is the cost of constructing a toilet in a country where many still suffer from extreme poverty. The present note therefore attempts to describe the construction of a very low cost toilet.

Components of a toilet

There are four components of a toilet, each with its separate costs. Let us first recognize these before we discuss how to reduce the cost of each component

1. The toilet bowl
2. Associated water supply and piping
3. The disposal system or pit
4. The Toilet room

Toilet Bowl:

Those who defecate in the open habitually squat down to do it. Therefore when seeking a toilet for such persons, one is looking for a squat down type of toilet bowl rather than a seat as in the west. Such toilet bowls in ceramic are widely available in developing countries and cost only a few hundred rupees. Ceramic toilets are the best option since they have a long life and can be cleaned easily.

However, let us also seek a lower cost option when even this is not possible. It is simply a conical cavity with a hole at the bottom made in cement right at site. Such holes are used in some rural areas like those of Egypt where they lead directly into a pit below it in ground. However the stench that emerges from such a hole is intolerable because of lack of a proper septic cavity and water trap.  Further, if a wedding ring falls into it, the house has to be brought down to recover it. Therefore some minor modifications are required of the cement bowl to overcome this problem. A simple modification of the cement bowl constructed on site can be made if before masonry work a wooden cylinder is fitted at the exit point and the traditional water trap as available with ceramic bowls is fitted at its end. When the cement work has dried and cured, the wooden cylinder can be pulled out creating a water trap as similar to that in a ceramic toilet. The additional cost of this modified system is merely the trap part of the ceramic bowl.

Associated piping and water supply:

In the low cost system unfortunately one has to give up on the idea of pulling a lever to flush since it has a cost and further many of the areas where such systems need to be installed do not even have running water supply. Water is drawn from a hand pump or well for consumption. However, throwing water in the toilet with buckets and mugs works fairly easily too. Some education is required for this though. Users have to be educated to wet the toilet with a couple of mugs of water before use, to prevent sticking and some water from a bucket later. If this is not done stench soon develops around a toilet. However, such education costs no more than a leaflet or an announcement in the media.

An item of piping is the one that connects the toilet seat to the septic pit or sewerage system. A sewerage system leading to a community level septic tank can be visualized for a cluster of homes but that is an exercise that would have to be done at public level. An easier solution is to have at home septic systems. A septic tank or septic pit is not necessary but rather a septic drain that his author learned about from his father (Colonel A. P. Malhotra), who was an officer in the corp. of engineers from British times is an ideal solution. It is described next. it was constructed in his large retirement home in Jaipur and required cleaning only once in twenty years.

The Septic Drain:

A septic tank requires much masonry and even a simple soak pit in the ground requires a concrete slab to cover, both costly items. These can be completely avoided in the septic drain as described next. This design is not described anywhere else in published literature yet. The only material required for it is five Ferro-cement or thin concrete tiles of dimensions, 1 foot x 2 feet. This can be made in moulds at home on pieces of newspaper or more cheaply by a local manufacturer on a larger scale. In some areas stone slabs of the same size are available cheaply and may be used instead.

The septic drain should be constructed as close to the toilet  as possible so that it is connected to the toilet seat by a three inch diameter plastic pipe of a length that is no more than a few feet to reduce cost. To construct the septic drain mark out an area of one feet into four feet on ground and scrape out the soil from within this rectangle gently to a depth of two feet. Then scrape out a six inch inch deep and six inch wide margin around it to rest tile covers as place for resting the covers and covering with soil. Next place one of the 1 foot into 2 feet concrete tile midway, placing it vertically by embedding it at the root of the drain so that only a foot of the top emerges from the ground. This way the septic drain is divided in two compartments the first one close to the toilet is connected to the pipe from the toilet. Most solid material will be retained in this compartment whereas liquid would flow into the second compartment and seep into the soil. The anaerobic bacterial action and ground filtration will prevent any pollution of sub-soil water. Throwing a thin layer of broken brick rubble at the floor of such a drain improves its efficiency.

The final step is covering the drain with the remaining four concrete tiles. The joints may be sealed with a little weak cement and sand mix in 1:12 ratio so as to permit easy removal from cleaning around once a year. Finally cover the tiles with soil and the septic drain is ready. A warning is in place that for the first few weeks or months a stench is likely to emanate from the drain but this will vanish soon as bacterial flora develop that will digest the waste over the years. Dimensions given here can be altered to suit available tiles . Smaller drains would require more frequent cleaning. If more space is available then extending the length of drain to six feet instead of four will work better, however width should not be increased beyond one feet. A plus point for the drain is safety. Children cannot fall down and drown in it nor can a person enter to get knocked out at the time of cleaning by poisonous gases.

Toilet Room:

Low Cost Toilet

A cheap option of the toilet room is 4.5 inch thick brick enclosure sans plaster of seven feet height without a roof (or a simple thatch roof) with a utility door in front. A second temporary improvisation is to dig in four wooden logs in four corners to create a 4 feet x 4 feet space. Bamboo bars may be tied secured at a height of seven feet to strengthen the structure. Three sides may then be covered with grass or jute matting and a jute drop down curtain can be installed in front.The brick structure on the other hand such as shown in figure would require about five hundred bricks and a bag of cement. The door even if in metal sheet would cost more but initially one may improvise with a curtain. The structure can be upgraded in future by adding a RCC roof at any time and even placing a plastic water tank on it in case water supply reaches the home; if it does, an ideal place to install a small connected wash basin would be in the open on a side outer wall of this toilet, that can be used for washing hands, shaving and brushing.

The enclosure can also be made in mud walls or mud bricks but if that is done it is a good idea to throw cement- water slurry on the inside walls to make them water proof. The walls in this case will be thicker, around ten inches thick. Mud bricks are made easily at home and adding five percent cement to the mix as well as rice husk/straw strengthens them. They would require around three weeks of drying time. The technology for these may be searched for easily since they are used widely around the world.

Required Materials

1. One 50 kg. bag Cement
2. Five 2 feet x 1 foot stone or cement tiles
3. Preferably one squat down type ceramic toilet bowl and trap
4. One five foot length, three inch diameter plastic pipe

Total Cost is approximately 1000 Rupees, less than twenty US dollars

Remaining materials may be improvised at site

Convert the Shit to Delicious fruit 

Trees growing in the author's home

Just as the waste and exhaled breath from plants is life for us, our waste is life for plants. The present septic drain is not lined and eminent for extraction of nutrients by tree and plant roots. If you plant a couple of fruit or food trees like drum-stick a few feet away from the septic drain, it shall draw the waste moisture, solids and other nutrients from the drain and convert that to delicious food. Large or small trees may be planted depending on space available and if little space is available, plant creeping food plants like grapes, gourd etc. to climb on home walls. Grape wines are an excellent climate control measure because they cool a home in summers and warm it in winter by shedding leaves exactly at the right time. Aside from the fruit the new leaves of the plant are also edible and widely used as such in Greece and other countries where this fruit grows. The author has been doing this in his urban home for years, that is why it is as lush green as the Himalayas or the rain forest even in a hot dry and semi desert city, as one of the photo here shows. Several more would be a found in a companion blog that is more philosophical and less technical at http://someitemshave.blogspot.com

Further Information:

A fellow blogger, Aditya Thakur,  has supplied a useful link (on Ecosan) as a starting point for a further exploration of the productive use of human waste
http://en.wikipedia.org/wiki/Ecological_sanitation

Note: Since this is a blog note and not a technical document many details were not entered. However, any competent engineer can work them out from the information provided. A suggestion is to try a few prototypes with feasible variations for demonstration and testing for a few months in chosen villages. The author will gladly supply more details if contacted, even through a comment to this note here.

UPDATE August 23, 2014

In response to a question by https://twitter.com/WaterAidUK on twitter if Narendra Modi government could rid the country of open defecation, the answer of this blogger was – Why not?

India requires less than twenty core toilets for the purpose (1 crore =100 lakh; 1 lakh = 100, 000). The suggested cost of 1000 rupees in this note is the bare minimum requiring a lot of improvisation. If it is assumed that two and a half times or 2500 rupees will be spent and all of this would be borne by the government, it requires 10 core thousands for four crore toilets per year. This year the government is likely to save forty thousand crores on diesel subsidy alone because of falling oil prices. The government gives a lot of subsidies of different kinds for the poor but directed to this cause it will be a source of relief and good health for all.