Dry toilet

A dry toilet is for depositing human excrement without using water, very different from flush toilets that use water. It may be for sitting or squatting. The urine may get mixed with the feces or be kept separate.

Dry toilets can be made for squatting (left) or sitting (right).

There are different types of dry toilets: composting toilet, urine-diverting dry toilet, Arborloo, container-based toilet, bucket toilet, pit latrine, incinerating toilet, or freezing toilet.

Types

All of these types of dry toilets work without flush water and without connections to sewers or septic tanks:^[1]

A Composting Toilet.

• Composting toilet - usually with feces, urine, and sometimes food waste mixed together.
• Urine-diverting dry toilet – with urine kept separate to be used as a fertilizer for plants, while the feces stay drier.^[2]
• Arborloo – which is like a pit latrine but the pit is smaller and the outhouse is light and can be moved to another pit, while a tree is planted on the old pit.
• Container-based toilet - with excrement going into containers that are taken to places where it is processed.
• Bucket toilet – simply a pail, but can also have urine separate and feces covered with dry material.
• Pit latrine - a hole in the ground.
• Incinerating toilet, freezing toilet – these are more complicated and expensive.

Other dry toilets are being developed, some with funding from the Bill and Melinda Gates Foundation.^[3]

Uses

A Urine-diverting Dry Toilet, with a funnel on the left to catch this liquid.

There are four main reasons for using dry toilets:

• To save water and therefore money;
• To prevent water pollution;
• To recycle nutrients in agriculture, after treatment and storage to kill diseases;
• For places where sewers and wastewater treatment are not possible.^[2]

An ArborLoo for planting trees.

Dry toilets can be very presentable and are used in developed countries (for example, Sweden, Finland, and Norway), where they are often found at summer houses and national parks. They are more common in developing countries in places where flush toilets are not possible or not desired. Sewers often cost too much where the land is rocky or irregular and where houses are far from one another.

Challenges

Some people strongly believe that dry toilets are the best way deal with excrement, others argue that they cannot be done everywhere, and others simply do not want to change their habits. Dry toilets reduce water consumption and pollution, recover valuable nutrients for agriculture, and (when managed properly) eliminate diseases and chemicals efficiently.^[4]

A Bucket Toilet, which is also a type of Container-based Toilet.

It has been difficult to install and manage many dry toilets in cities (for example, in the Erdos Eco-City of the Inner Mongolia Autonomous Region of China).^[5] Designs need to be fine-tuned and carefully constructed and managed.^[4] The users also need to learn about the benefits of dry toilets and how to properly use them.

History

Nearly all toilets were dry toilets, and excrement was valued in agriculture, until flush toilets were invented.

Great Britain

In Britain, dry toilets were still used in some areas (including cities) until the 1940s. It seems that these were often emptied directly onto gardens, where the excreta was used as fertiliser. Sewer systems did not come to some rural areas in Britain until the 1950s or later.^[6]

Australia

Brisbane, Australia, was largely unsewered until the early 1970s, with many suburbs having dry toilets (called "dunnies") behind each house.

A pit latrine. (This kind of manual emptying should always be avoided.)

• 
  Nutrients recycle through the soil
• 
  Historical German dry toilet with a mechanism to add peat moss to cover feces

Related pages

• Sanitation
• Waste management

References

1. Tilley, Elizabeth; et al. (2014). Compendium of Sanitation Systems and Technologies (2nd Rev. ed.). Duebendorf, Switzerland: Swiss Federal Institute of Aquatic Science and Technology (Eawag). ISBN 978-3-906484-57-0.
2. Esrey S.A., Gough, J., Rapaport, D., Sawyer, R., Simpson-Hebert, M., Vargas, J., Winblad, U.,(eds). 1998. Ecological Sanitation. Sida. Stockholm.
3. Shaw, R. (2014). A Collection of Contemporary Toilet Designs. EOOS and WEDC, Loughborough University, UK. p. 40. ISBN 978 1 84380 155 9.
4. Flores, A. (2010). Towards sustainable sanitation: evaluating the sustainability of resource-oriented sanitation. PhD Thesis, University of Cambridge, UK
5. Rosemarin, Arno; McConville, Jennifer; Flores, Amparo; Qiang, Zhu (2012). The Challenges of Urban Ecological Sanitation: Lessons from the Erdos Eco-Town Project. Practical Action Publishers. p. 116. ISBN 1853397687.
6. Lewis, Dulcie (1996). Kent privies. Newbury: Countryside Books 1st.ed. edition (10 Oct. 1996). p. 128. ISBN 978-1853064197.

Other websites

• Global Dry Toilet Association of Finland Archived 2017-09-16 at the Wayback Machine
• Sustainable Sanitation Alliance Discussion Forum
• Dry toilet publications in the library of the Sustainable Sanitation Alliance
• InodoroSeco Blog of experiences and ideas about dry toilets (in Spanish and English)