![Schematic of the Dry Toilet](https://upload.wikimedia.org/wikipedia/commons/6/62/Schematic_of_the_Dry_Toilet.png)
A dry toilet (or non-flush toilet, no flush toilet or toilet without a flush) is a
toilet
A toilet is a piece of sanitary hardware that collects human urine and feces, and sometimes toilet paper, usually for disposal. Flush toilets use water, while dry or non-flush toilets do not. They can be designed for a sitting position popu ...
which, unlike a
flush toilet
A flush toilet (also known as a flushing toilet, water closet (WC) – see also toilet names) is a toilet that disposes of human waste (principally urine and feces) by using the force of water to ''flush'' it through a drainpipe to another lo ...
, does not use flush water.
Dry toilets do not use water to move excreta along or block odors.
They do not produce
sewage
Sewage (or domestic sewage, domestic wastewater, municipal wastewater) is a type of wastewater that is produced by a community of people. It is typically transported through a sewer system. Sewage consists of wastewater discharged from residenc ...
, and are not connected to a
sewer system
Sewerage (or sewage system) is the infrastructure that conveys sewage or surface runoff ( stormwater, meltwater, rainwater) using sewers. It encompasses components such as receiving drains, manholes, pumping stations, storm overflows, and sc ...
or
septic tank
A septic tank is an underground chamber made of concrete, fiberglass, or plastic through which domestic wastewater (sewage) flows for basic sewage treatment. Settling and anaerobic digestion processes reduce solids and organics, but the treatme ...
. Instead,
excreta
Excretion is a process in which metabolic waste
is eliminated from an organism. In vertebrates this is primarily carried out by the lungs, kidneys, and skin. This is in contrast with secretion, where the substance may have specific tasks after lea ...
falls through a drop hole.
A variety of dry toilets exist, ranging from simple
bucket toilet
A bucket toilet is a basic form of a dry toilet whereby a bucket (pail) is used to collect excreta. Usually, feces and urine are collected together in the same bucket, leading to odor issues. The bucket may be situated inside a dwelling, or in ...
s to specialized
incinerating
Incineration is a waste treatment process that involves the combustion of substances contained in waste materials. Industrial plants for waste incineration are commonly referred to as waste-to-energy facilities. Incineration and other high ...
and
freezing
Freezing is a phase transition where a liquid turns into a solid when its temperature is lowered below its freezing point. In accordance with the internationally established definition, freezing means the solidification phase change of a liquid o ...
toilets.
Types
![Utedo](https://upload.wikimedia.org/wikipedia/commons/c/cb/Utedo.JPG)
Types of dry toilet, listed in approximate order from simplest to most complex, include:
*
Bucket toilet
A bucket toilet is a basic form of a dry toilet whereby a bucket (pail) is used to collect excreta. Usually, feces and urine are collected together in the same bucket, leading to odor issues. The bucket may be situated inside a dwelling, or in ...
– The most basic kind of toilet. May have a toilet seat, with or without a lid. May be accompanied by material (e.g. wood ash, sawdust, or quick lime) to cover excreta after use.
*
Pit latrine
A pit latrine, also known as pit toilet, is a type of toilet that collects human feces 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 ...
– excluding pour-flush versions with water seal
*
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 m ...
– urine and feces
collected separately
*
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 ou ...
**
Arborloo
An arborloo is a simple type of composting toilet in which feces are collected in a shallow pit and a fruit tree is later planted in the fertile soil of the full pit. Arborloos have: a pit like a pit latrine but less deep; a concrete, ferrocement ...
– shallow pit latrine designed for making compost
**
Treebog
A treebog is a type of low-tech compost toilet. It consists of a raised platform above a compost pile surrounded by densely planted willow trees or other nutrient-hungry vegetation. It can be considered an example of permaculture design, as it f ...
- on a raised platform above a compost pile, surrounded by densely planted willow trees (or similar)
*
Container-based toilet
Container-based sanitation (abbreviated as CBS) refers to a sanitation system where toilets collect human excreta in sealable, removable containers (also called cartridges) that are transported to treatment facilities. This type of sanitation ...
- excreta is collected in sealable, removable containers (also called cartridges) which are later transported to waste treatment facilities
** Packaging toilet – packages feces separately after each use
*
Incinerating toilets and
freezing toilet Freezing toilet is a kind of dry toilet powered by electricity which freezes the content in a short time. Freezing toilets work by electricity, as they are plugged into the wall. They do not need water, pipes, ventilation or chemicals to work.
The f ...
s – More complex technology than most dry toilets. Require electricity (or other suitable energy source) to function.
Other types of dry toilets are under development at universities, for example since 2012 funded by the
Bill and Melinda Gates Foundation
The Bill & Melinda Gates Foundation (BMGF), a merging of the William H. Gates Foundation and the Gates Learning Foundation, is an American private foundation founded by Bill Gates and Melinda French Gates. Based in Seattle, Washington, it was ...
. Such toilets are meant to operate
off-the-grid
Off-the-grid or off-grid is a characteristic of buildings and a lifestyle designed in an independent manner without reliance on one or more public utilities. The term "off-the-grid" traditionally refers to not being connected to the electrical gr ...
without connections to water, sewer, or electrical lines.
Terminology
One important source states that the term "dry toilet" should only refer to the "user interface" and not the subsequent storage and treatment steps.
However, in the
WASH
WASH (or Watsan, WaSH) is an acronym that stands for "water, sanitation and hygiene". It is used widely by non-governmental organizations and aid agencies in developing countries. The purposes of providing access to WASH services include achievin ...
sector, the term "dry toilet" is still used differently by different people. It often includes also the storage and treatment steps. For example, it is common that the term "dry toilet" is used to refer specifically to a urine-diverting dry toilet or a composting toilet.
[Platzer, C., Hoffmann, H., Ticona, E. (2008)]
Alternatives to waterborne sanitation - a comparative study – limits and potentials
IRC Symposium: Sanitation for the urban poor - partnerships and governance, Delft, The Netherlands[Flores, A. (2010)]
''Towards sustainable sanitation: evaluating the sustainability of resource-oriented sanitation''
PhD Thesis, University of Cambridge, UK
People also use the term to refer to a pit latrine without a water seal even though the pit of a pit latrine is not usually dry. The pit can become very wet because urine mixes with feces in the pit and
drainage
Drainage is the natural or artificial removal of a surface's water and sub-surface water from an area with excess of water. The internal drainage of most agricultural soils is good enough to prevent severe waterlogging (anaerobic conditio ...
might be limited. Also,
groundwater
Groundwater is the water present beneath Earth's surface in rock and soil pore spaces and in the fractures of rock formations. About 30 percent of all readily available freshwater in the world is groundwater. A unit of rock or an unconsolidate ...
or
surface water
Surface water is water located on top of land forming terrestrial (inland) waterbodies, and may also be referred to as ''blue water'', opposed to the seawater and waterbodies like the ocean.
The vast majority of surface water is produced by prec ...
can also get into the pit in the event of heavy rains or flooding. Sometimes households even discard
greywater
Greywater (or grey water, sullage, also spelled gray water in the United States) refers to domestic wastewater generated in households or office buildings from streams without fecal contamination, i.e., all streams except for the wastewater from ...
(from showering) into the same pit.
Some publications use the term "dry sanitation" to denote a system that includes dry toilets (in particular urine-diverting dry toilets) connected to a system to manage the excreta.
However, this term is not in widespread use nowadays, and might rather be replaced with "non sewer-based sanitation" or "non-sewered sanitation" (see also
fecal sludge management
Fecal sludge management (FSM) (or faecal sludge management in British English) is the storage, collection, transport, treatment and safe end use or disposal of fecal sludge. Together, the collection, transport, treatment and end use of fecal slud ...
).
The term "
outhouse
An outhouse is a small structure, separate from a main building, which covers a toilet. This is typically either a pit latrine or a bucket toilet, but other forms of dry toilet, dry (non-flushing) toilets may be encountered. The term may als ...
" refers to a small structure, separate from a main building, which covers a pit toilet or a dry toilet. Although it strictly refers only to the structure above the toilet, it is often used to denote the entire toilet structure, i.e. including the hole in the ground in the case of a pit latrine.
Gallery
File:Cleaning a urine-diverting dry toilet (UDDT) in Johannesburg (2947142348).jpg, A 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 m ...
in South Africa.
File:Compost toilet.jpg, 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 ou ...
at Activism Festival 2010 in the mountains outside Jerusalem.
File:Clivus Multrum Composting toilet with urine diversion-dehydration.svg, A 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 ou ...
schematic (Clivus Multrum
Clivus Multrum is a type of composting toilet and the name of a company that markets this brand name of composting toilets. " Clivus" is Latin for incline or slope; "multrum" is a Swedish composite word meaning "compost room", thus a "Clivus Mul ...
).
File:Arborloo-en.svg, An Arborloo
An arborloo is a simple type of composting toilet in which feces are collected in a shallow pit and a fruit tree is later planted in the fertile soil of the full pit. Arborloos have: a pit like a pit latrine but less deep; a concrete, ferrocement ...
for later planting trees.
File:Humanure dry toilet inside view, Mongolian family house, Ulaan Baatar 2010, by Wolfgang Berger (6211327744).jpg, A container-based toilet
Container-based sanitation (abbreviated as CBS) refers to a sanitation system where toilets collect human excreta in sealable, removable containers (also called cartridges) that are transported to treatment facilities. This type of sanitation ...
or bucket toilet
A bucket toilet is a basic form of a dry toilet whereby a bucket (pail) is used to collect excreta. Usually, feces and urine are collected together in the same bucket, leading to odor issues. The bucket may be situated inside a dwelling, or in ...
, another type of dry toilet.
File:Defecating into a pit (schematic).jpg, Schematic of a simple pit latrine
A pit latrine, also known as pit toilet, is a type of toilet that collects human feces 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 ...
with a squatting pan and shelter.
Uses
![Henry Moule's earth closet, improved version c1875](https://upload.wikimedia.org/wikipedia/commons/c/c8/Henry_Moule%27s_earth_closet%2C_improved_version_c1875.JPG)
Dry toilets (in particular simple pit latrines) are used in developing countries in situations in which flush toilets connected to septic tanks or sewer systems are not possible or not desired, for example due to costs. Sewerage infrastructure costs can be very high in instances of unfavorable terrain or sprawling settlement patterns.
Dry toilets (in particular composting toilets) are also used in rural areas of developed countries, e.g. many Scandinavian countries (Sweden, Finland, Norway) for summer houses and in national parks.
Advantages
Dry toilets can be a suitable alternative to
water-flushed toilets when water for flushing is of short supply.
[Rieck, C., von Münch, E., Hoffmann, H. (2012). Technology review of urine-diverting dry toilets (UDDTs) – Overview on design, management, maintenance and costs. Deutsche Gesellschaft fuer Internationale Zusammenarbeit (GIZ) GmbH, Eschborn]
Germany
/ref> Another reason for using dry toilets can be that the infrastructure to deal with the wastewater produced from flush toilets is too expensive to construct.
Dry toilets are used for three main reasons instead of flush toilets:
# To save water – when there is either water scarcity
Water scarcity (closely related to water stress or water crisis) is the lack of fresh water Water resources, resources to meet the standard water demand. There are two types of water scarcity: physical or economic water scarcity. Physical water ...
, water is costly (such as in arid
A region is arid when it severely lacks available water, to the extent of hindering or preventing the growth and development of plant and animal life. Regions with arid climates tend to lack vegetation and are called xeric or desertic. Most ar ...
or semi-arid
A semi-arid climate, semi-desert climate, or steppe climate is a dry climate sub-type. It is located on regions that receive precipitation below potential evapotranspiration, but not as low as a desert climate. There are different kinds of semi-ar ...
climates) or because the user wants to save water for environmental reasons. However, water savings from dry toilets might be insignificant compared to other possible water savings in households or within agricultural practices.
#To prevent pollution of surface water or groundwater
Groundwater is the water present beneath Earth's surface in rock and soil pore spaces and in the fractures of rock formations. About 30 percent of all readily available freshwater in the world is groundwater. A unit of rock or an unconsolidate ...
– dry toilets do not mix excreta with water and do not pollute groundwater (except for pit latrines which may pollute groundwater); they do not contribute to eutrophication
Eutrophication is the process by which an entire body of water, or parts of it, becomes progressively enriched with minerals and nutrients, particularly nitrogen and phosphorus. It has also been defined as "nutrient-induced increase in phytopla ...
in surface water bodies.
# To enable safe reuse of excreta
Reuse of human excreta is the safe, beneficial use of treated human excreta after applying suitable treatment steps and risk management approaches that are customized for the intended reuse application. Beneficial uses of the treated excreta may ...
, after the collected excreta or fecal sludge
Fecal sludge management (FSM) (or faecal sludge management in British English) is the storage, collection, transport, treatment and safe end use or disposal of fecal sludge. Together, the collection, transport, treatment and end use of fecal slud ...
has undergone further treatment for example by drying or composting
Compost is a mixture of ingredients used as plant fertilizer and to improve soil's physical, chemical and biological properties. It is commonly prepared by decomposing plant, food waste, recycling organic materials and manure. The resulting m ...
.
Dry toilets and excreta management without sewers can offer more flexibility in construction than flush toilet and sewer-based systems. It can be a suitable system to adapt to climate change scenarios
Climate change scenarios or socioeconomic scenarios are projections of future greenhouse gas (GHG) emissions used by analysts to assess future vulnerability to climate change. Scenarios and pathways are created by scientists to survey any long ...
in desert-like areas like Lima
Lima ( ; ), originally founded as Ciudad de Los Reyes (City of The Kings) is the capital and the largest city of Peru. It is located in the valleys of the Chillón River, Chillón, Rímac River, Rímac and Lurín Rivers, in the desert zone of t ...
, Peru.
Challenges
Dry toilets do not have a water seal, thus odors
An odor (American English) or odour (Commonwealth English; see spelling differences) is caused by one or more volatilized chemical compounds that are generally found in low concentrations that humans and animals can perceive via their sense ...
may be a problem. This is often the case for pit latrines, UDDTs or composting toilets if they are not designed well or not used properly.
Dry toilets that are connected to a pit (such as pit latrines) tend to make it very difficult to empty the pit in a safe manner when they are full (see fecal sludge management
Fecal sludge management (FSM) (or faecal sludge management in British English) is the storage, collection, transport, treatment and safe end use or disposal of fecal sludge. Together, the collection, transport, treatment and end use of fecal slud ...
). On the other hand, dry toilets that are not connected to a pit (e.g. container-based toilets, UDDTs and composting toilets) usually have a safe method for emptying built into them as they are designed to be emptied on a regular and quite frequent basis (within days, weeks or months).
History
The history of dry toilets is essentially the same as the history of toilet
A toilet is a piece of sanitary hardware that collects human urine and feces, and sometimes toilet paper, usually for disposal. Flush toilets use water, while dry or non-flush toilets do not. They can be designed for a sitting position popu ...
s in general (until the advent of flush toilet
A flush toilet (also known as a flushing toilet, water closet (WC) – see also toilet names) is a toilet that disposes of human waste (principally urine and feces) by using the force of water to ''flush'' it through a drainpipe to another lo ...
s) as well as the history of 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 ...
systems with regards to reuse of excreta
Reuse of human excreta is the safe, beneficial use of treated human excreta after applying suitable treatment steps and risk management approaches that are customized for the intended reuse application. Beneficial uses of the treated excreta may ...
in agriculture.
Dry earth closets
Dry earth closets were invented by English clergyman Henry Moule
Henry Moule (1801–1880) was a priest in the Church of England and inventor of the dry earth toilet, a type of pail closet.
Life Education and priesthood
Moule, sixth son of George Moule, solicitor and banker, was born at Melksham, Wiltshire, ...
, who dedicated his life to improving public sanitation after witnessing the cholera epidemics of 1849 and 1854. Impressed by the insalubrity of the houses, especially during the Great Stink
The Great Stink was an event in Central London during July and August 1858 in which the hot weather exacerbated the smell of untreated human waste and industrial effluent that was present on the banks of the River Thames. The problem had bee ...
in the summer of 1858, he invented what he called the 'dry earth system'.
In partnership with James Bannehr, he patented his device (No. 1316, dated 28 May 1860). Among his works bearing on the subject were ''The Advantages of the Dry Earth System ''(1868), ''The Impossibility overcome: or the Inoffensive, Safe, and Economical Disposal of the Refuse of Towns and Villages (''1870), The ''Dry Earth System'' (1871), ''Town Refuse, the Remedy for Local Taxation'' (1872), and ''National Health and Wealth promoted by the general adoption of the Dry Earth System'' (1873). His system was adopted in private houses, in rural districts, in military camps, in many hospitals, and extensively in the British Raj
The British Raj (; from Hindi ''rāj'': kingdom, realm, state, or empire) was the rule of the British Crown on the Indian subcontinent;
*
* it is also called Crown rule in India,
*
*
*
*
or Direct rule in India,
* Quote: "Mill, who was himsel ...
. Ultimately, however, it failed to gain public support as attention turned to the water-flushed toilet
A toilet is a piece of sanitary hardware that collects human urine and feces, and sometimes toilet paper, usually for disposal. Flush toilets use water, while dry or non-flush toilets do not. They can be designed for a sitting position popu ...
connected to a sewer system.
In Germany, a dry toilet with a peat dispenser was marketed until after the Second World War. It was called "Metroclo" and was manufactured by Gefinal, Berlin.
Great Britain
In Britain, use of dry toilets continued in some areas, often urban areas, through to the 1940s. It seems that these were often emptied directly onto their gardens, where the excreta was used as fertilizer. Sewer systems did not come to some rural areas in Britain until the 1950s or even after that.
Australia
Brisbane
Brisbane ( ) is the capital and most populous city of the states and territories of Australia, Australian state of Queensland, and the list of cities in Australia by population, third-most populous city in Australia and Oceania, with a populati ...
, Australia was largely unsewered until the early 1970s, with many suburbs having a dry toilet (called a dunny
An outhouse is a small structure, separate from a main building, which covers a toilet. This is typically either a pit latrine or a bucket toilet, but other forms of dry (non-flushing) toilets may be encountered. The term may also be used t ...
) behind each house. Academic George Seddon claimed that "the typical Australian back yard in the cities and country towns" had, throughout the first half of the twentieth century, "a dunny against the back fence, so that the pan could be collected from the dunny lane through a trap-door".
References
External links
Global Dry Toilet Association of Finland
Dry toilet publications
in library of Sustainable Sanitation Alliance
The Sustainable Sanitation Alliance (SuSanA) is a loose network of organizations who are "working along the same lines towards achieving sustainable sanitation". It began its work in 2007, one year before the United Nations International Year o ...
{{DEFAULTSORT:Dry toilet
Toilet types
Sanitation
Water conservation