Tiger worm toilets: lessons learned from constructing household vermicomposting toilets in Liberia

David Watako; Koslengar Mougabe; Thomas Heath

doi:10.3362/1756-3488.2016.012

Tiger worm toilets: lessons learned from constructing household vermicomposting toilets in Liberia

David Watako | Koslengar Mougabe | Thomas Heath

In response to the poor urban sanitation in Monrovia’s slums and Buchanan’s peri-urban areas in Liberia, Oxfam piloted worm toilets (aka Tiger Toilets), constructing 180 toilets between 2011 and 2015. One toilet was constructed per household for families containing fewer than 10 people. Each toilet was connected to a biodigester containing 2 kg of African night crawlers (Eudrilus eugeniae). This paper documents the programme approach including how the community was mobilized and the construction process. The results section reviews field observations, challenges, and the maintenance problems encountered. In the discussion the paper reviews the design changes, lessons learned, limits for scale, and critical factors for success (favourable environment, local supply, infiltration capacity, and local technicians). The paper concludes that although the project is still ongoing, the study suggests that the African night crawlers can digest significant volumes of human excreta if proper conditions of aeration, moisture, and temperature are met.

BioLet (2015) ‘The theory behind composting toilets’ [online] <http://biolet.ehowplus.net/resources/id/The-Theory-behind-Composting-Toilets> [accessed 27 January 2015].

FAO (2015) ‘On farm composting methods: vermicomposting’ [online], Corporate Document Repository, FAO <www.fao.org/docrep/007/y5104e/y5104e08.htm> [accessed 17 October 2015].

Furlong, C., Templeton, M.R. and Gibson, W.T. (2014) ‘Processing of human faeces by wet vermifiltration for improved on-site sanitation’, Journal of Water, Sanitation and Hygiene for Development 4(2): 231–9 <http://dx.doi.org/10.2166/washdev.2014.107>.

Furlong C., Gibson, W.T., Patankar, R., Savant, S. and Oak, A. (2015) ‘Faecal sludge treatment by vermifiltration: proof of concept’, Briefing paper 2308, in Water Sanitation and Hygiene Services Beyond 2015: Improving Access and Sustainability, 38th WEDC International Conference, Loughborough University, UK, pp. 4–6.

Government of Liberia (2015) Ebola Virus Disease (EVD) Infection Prevention and Control Standard Operating Procedures (SOP) For Health Clinics, Health Centers and Hospitals, Greater Monrovia, Liberia: Ministry of Health and Social Welfare, Government of Liberia.

International Training Network Bangladesh University of Engineering and Technology (ITN-BUET) (2015) ‘Preliminary evaluation of sanitation technologies’, in SanMark-CITY: Intelligent Design in Urban Sanitation Marketing, Fostering Adaptation and Evolution of Innovative Technologies for Urban On-Site Sanitation in Bangladesh, Dhaka, Bangladesh: International Training Network Centre (ITN‐BUET).

IRIN (2009) ‘Liberia: disease rife as more people squeeze into fewer toilets’ [online] <www.irinnews.org/report/87110/liberia-disease-rife-as-more-people-squeeze-into-fewer-toilets> [accessed 17 October 2015].

Medecins Sans Frontieres (MSF) (2008) ‘MSF responds to cholera outbreak in Liberia’ [online], Stories from the Frontline <www.msf.org.uk/article/msf-responds-cholera-outbreak-liberia> [accessed 19 October 2015].

Rodriguez, A.C. and Lapeire, I.R. (1992) ‘Increase in weight, length and number of segments of Eudrilus eugeniae (Oligochaeta: Eudrilidae) at 24°C’, Revista de Biologia Tropical 6(215).

Vijaya, T.M., Middha, S.K., Usha, T., Aruna, H.K., Bharathi, R., Saini, D. and Govindaraj, G. (2012) ‘Morphological and histological studies on the vermicomposting Indian earthworm Eudrilus eugeniae’, World Journal of Zoology 7(2): 165–70 <http://dx.doi.org/10.5829/idosi.wjz.2012.7.2.62154>.

World Bank (2015) ‘World development indicators’ [online] <http://data.worldbank.org/indicator/NY.GDP.PCAP.CD/countries> [accessed 17 October 2015].

World Population Review (2015) ‘Liberia population’ [online]<http://worldpopulationreview.com/countries/liberia-population/> [accessed 17 October 2015].

WHO/UNICEF Joint Monitoring Programme (JMP) for Water Supply and Sanitation <www.wssinfo.org/> [accessed 17 October 2015].