
An arborloo is a simple type of
composting toilet
A composting toilet is a type of dry toilet that treats human waste by a biological process called composting. This process leads to the decomposition of organic matter and turns human waste into compost-like material. Composting is carried out b ...
in which
feces
Feces (also known as faeces American and British English spelling differences#ae and oe, or fæces; : faex) are the solid or semi-solid remains of food that was not digested in the small intestine, and has been broken down by bacteria in the ...
are collected in a shallow pit and a
fruit tree
A fruit tree is a tree which bears fruit that is consumed or used by animals and humans. All trees that are flowering plants produce fruit, which are the ripened ovaries of flowers containing one or more seeds. In horticultural usage, the te ...
is later planted in the
fertile soil
Soil, also commonly referred to as earth, is a mixture of organic matter, minerals, gases, water, and organisms that together support the life of plants and soil organisms. Some scientific definitions distinguish dirt from ''soil'' by re ...
of the full pit. Arborloos have: a pit like a
pit latrine
A pit latrine, also known as pit toilet, is a type of toilet that collects human waste in a hole in the ground. Urine and feces enter the pit through a drop hole in the floor, which might be connected to a toilet seat or squatting pan for user ...
but less deep; a
concrete
Concrete is a composite material composed of aggregate bound together with a fluid cement that cures to a solid over time. It is the second-most-used substance (after water), the most–widely used building material, and the most-manufactur ...
,
ferrocement or other strong floor; a superstructure (toilet house or
outhouse
An outhouse — known variously across the English-speaking world otherwise as bog, dunny, long-drop, or privy — is a small structure, separate from a main building, which covers a toilet. This is typically either a pit latrine or a bucket ...
) to provide privacy; and possibly a ring beam to protect the pit from collapsing.
The pit should remain well above the
water table
The water table is the upper surface of the phreatic zone or zone of saturation. The zone of saturation is where the pores and fractures of the ground are saturated with groundwater, which may be fresh, saline, or brackish, depending on the loc ...
in the soil, so as to not
contaminate groundwater
Groundwater is the water present beneath Earth's surface in rock and Pore space in soil, soil pore spaces and in the fractures of stratum, rock formations. About 30 percent of all readily available fresh water in the world is groundwater. A unit ...
.
The arborloo works by temporarily putting the slab and superstructure above a shallow pit while it fills. Feces, urine, paper, leaves, other materials for wiping, and potentially
anal wash water all go into the pit. After each use, a cup of the excavated soil should be added to help to control smell and flies. When the pit is nearly full, the outhouse and slab are moved to a newly dug pit and the old pit is covered with some of the earth from the new pit and left to compost. A fruit tree or other useful vegetation is planted in the old pit, preferably during the rainy season.
Feces are safely stored and converted in the soil, avoiding
disease
A disease is a particular abnormal condition that adversely affects the structure or function (biology), function of all or part of an organism and is not immediately due to any external injury. Diseases are often known to be medical condi ...
transmission, and do not have to be processed or manipulated by anyone. Instead, fruits on trees are grown, fertilised by human excreta.
The arborloo is a type of
dry toilet
A dry toilet (or non-flush toilet, no flush toilet or toilet without a flush) is a toilet which, unlike a flush toilet, does not use flush water. Dry toilets do not use water to move excreta along or block odors. They do not produce sewage, and a ...
. By using the nutrient-rich soil of a retired pit, the arborloo, in effect, treats feces as a resource rather than a waste product. Arborloos are used in rural areas of many
developing countries
A developing country is a sovereign state with a less-developed Secondary sector of the economy, industrial base and a lower Human Development Index (HDI) relative to developed countries. However, this definition is not universally agreed upon. ...
, for example in Zimbabwe, Malawi and Ethiopia.
Design
The defecation pit may be circular or square and this may depend on the slab and superstructure. A circular pit is less likely to collapse.
The pit of the arborloo is shallow (between deep).
If the pit is dug by hand it must have a diameter of at least to accommodate effective digging.
The floor should be at least wider than the pit, to allow for its stability.
If the floor is round and unattached to the outhouse, it can be rolled to the new pit.
A roof is optional, especially if the floor is made such that rain runoff does not flow into the pit. The advantages of not making a roof include: more light, better ventilation, automatic rinsing with the rain,
disinfection via solar ultraviolet radiation, reduced cost, and less weight.
See also
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Ecological sanitation
Ecological sanitation, commonly abbreviated as ecosan (also spelled eco-san or EcoSan), is an approach to sanitation provision which aims to safely reuse excreta in agriculture. It is an approach, rather than a technology or a device which is ch ...
*
Reuse of excreta
Reuse of human excreta is the safe, beneficial use of treated human waste, human excreta after applying suitable treatment steps and risk management approaches that are customized for the intended reuse application. Beneficial uses of the treated ...
*
Treebog, another version
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Urine-diverting dry toilet
A urine-diverting dry toilet (UDDT) is a type of dry toilet with urine diversion that can be used to provide safe, affordable sanitation in a variety of contexts worldwide. The separate collection of feces and urine without any flush water has ...
*
Waterless urinal
References
External links
{{Permaculture
Toilets
Toilet types
Phytoremediation plants
Home composting
Permaculture
Sustainable building
Sustainable technologies
Bioremediation