Urinal

A urinal is used only for collecting urine. Urinals are generally for men, although models for women have also been developed. Most urinals use water for flushing, but waterless urinals are becoming increasingly popular.

Urinals for women consist of raised foot-steps and a sloped channel or catchment area that conducts the urine to a collection technology. For men, urinals can be either vertical wall-mounted units, or squat slabs over which the user squats.

The urinal can be used with or without water and the plumbing can be developed accordingly. If water is used, it is mainly used for cleaning and limiting odours (with a water-seal).

 





Design Considerations

For water-based urinals, the water use per flush ranges from less than 2 L in current designs to almost 20 L of flushwater in outdated models. Water-saving or waterless technologies should be favoured. To minimize odours and nitrogen loss in simple waterless urinal designs, the collection pipe should be submerged in the urine tank to provide a basic liquid seal.

Waterless urinals are available in a range of styles and complexities. Some urinals come equipped with an odour seal that may have a mechanical closure, a membrane, or a sealing liquid.

By putting a small target, or painted fly near the drain, the amount of spraying or splashing can be reduced; this type of user-guidance can help improve the cleanliness of the facility. Because the urinal is exclusively for urine it is important to also provide a toilet to be used for faeces.

Appropriateness

Urinals can be used in homes as well as within publicfacilities. In some cases, the provision of a urinal is useful to prevent the misuse of dry systems (e.g. UDDT).Portable waterless urinals have been developed for use at large festivals, concerts and other gatherings, to improve the sanitation facilities and reduce the point load of wastewater discharged at the site. In this way, a large volume of urine can be collected (and either used or discharged at a more appropriate location or time). The remaining toilets can be reduced in number or used more efficiently.

Health Aspects/Acceptance

The urinal is a comfortable and easily accepted user interface. Although simple in construction and design, urinals can have a large impact on the well-being of a community. When men have access to a urinal, they may urinate less often in public, which reduces unwanted odours and makes women feel more comfortable. Men have generally accepted waterless urinals, as they do not call for any change of behaviour.

Operation & Maintenance

Maintenance is simple, but should be done frequently, especially for waterless urinals. All of the surfaces should be cleaned regularly (bowl, slab and wall) to prevent odours and to minimize the formation of stains.

Particularly, in waterless urinals, calcium- and magnesium- based minerals and salts can precipitate and build up in pipes and on surfaces where urine is constantly present. Washing the bowl with a mild acid (e.g., vinegar) and/or hot water can prevent the build-up of mineral deposits and scaling. Stronger (> 24% acetic) acid or a caustic soda solution (2 parts water to 1 part soda) can be used for removing blockages. However, in some cases manual removal may be required.

For waterless urinals, it is critical to regularly check the functioning of the odour seal.




References

  • AUSTIN, A.; DUNCKER, L. (2002): Urine-diversion. Ecological Sanitation Systems in South Africa. Pretoria: Council for Scientific and Industrial Research (CSIR).

  • MUENCH, E. (2009): Waterless urinals: A proposal to save water and recover urine nutrients in Africa. In: Proceeding of the 34th WEDC International Conference, Addis Ababa, Ethiopia, 2009.URL [Accessed: 10.08.2010]. PDF

  • MUENCH, E. von; WINKER, M. (2011): Technology Review of Urine Diversion Components. Overview of Urine Diversion Components such as Waterless Urinals, Urine Diversion Toilets, Urine Storage and Reuse Systems. Eschborn: Deutsche Gesellschaft für Internationale Zusammenarbeit (GIZ) GmbH. URL [Accessed: 16.10.2013]. PDF

  • NWP (Editor) (2006): Smart Sanitation Solutions. Examples of innovative, low-cost technologies for toilets, collection, transportation, treatment and use of sanitation products. Amsterdam: Netherlands Water Partnership (NWP). URL [Accessed: 13.04.2010]. PDF

Further Readings

  • Cover image of a reference journal article.

    MUENCH, E. (2009): Waterless urinals: A proposal to save water and recover urine nutrients in Africa. In: Proceeding of the 34th WEDC International Conference, Addis Ababa, Ethiopia, 2009.URL [Accessed: 10.08.2010]. PDF

    Waterless urinals save water and they allow the collection of undiluted urine, which – because of its nitrogen and phosphorus content - is a valuable resource as fertiliser in agriculture. In the context of African developing countries, costs and maintenance requirements of waterless urinals need to be as low as possible. Despite the fact that hundreds of thousands of waterless (and odourless) urinals are now already in use worldwide, many municipalities are not yet aware of their existence or are reluctant to accept them as a viable option. This paper aims to reduce this knowledge gap by describing available models, odour control methods in waterless urinals (flat rubber tube, silicon curtain valve or sealant liquid), and the aspects to be considered regarding maintenance requirements and costs.

Case Studies

  • Cover image of a reference book or miscellany.

    WINKER, M.; GROENWALL, P.N. (2010): Waterless urinal sheds in the inner city, Hamburg, Germany. Eschborn: Sustainable Sanitation Alliance (SuSanA). URL [Accessed: 10.08.2010]. PDF

    In 1994 the BSU (“Office for urban development and environment”) developed a general concept for the construction and maintenance of the public toilets in order to reduce annual operation and maintenance costs. All urinals installed in Hamburg’s public toilets today are waterless urinals (instead of conventional water flushed urinals which use 4-6 L per flush). In eleven urinal sheds, urine storage tanks were also installed. This urinal sheds have reduced costs than the other public urinals and it is possible, that the collected urine will be used in agriculture in the future.

Awareness Material

  • Cover image of a reference journal article.

    GEORGE, R. (2009): Yellow is the new Green. In: The New Your Times, 27.URL [Accessed: 27.07.2010]. PDF

    This opinion contribution from Rose George published in the New York Times emphasises the enormous potential urine as a sustainable fertiliser source.

Important Weblinks

  • http://www.flickr.com [Accessed: 23.09.2013]

    SuSanA Flickr picture collection on Waterless Urinals.

  • http://www.novaquatis.eawag.ch/ [Accessed: 10.08.2010]

    Novaquatis – a cross-cutting Eawag research project was concerned with urine source separation as a new element in wastewater management.