Alternative Sanitation in Protracted Emergencies

Principal Investigator: Thomas Handzel, Centers for Disease Control and Prevention

What did this study set out to achieve?

This mixed methods study aimed to determine the safety and acceptability of UDDTs in refugee camps to provide evidence and inform guidance on their use at scale in humanitarian crises. It examined the performance and use of the toilets under real field conditions, with findings feeding back into their on-site management to create a safe end product and strengthen best practices.

To evaluate the biological performance of the UDDTs, a selection of 20 were seeded with known quantities of parasitic worm eggs, and samples were collected and analysed at regular intervals over a 12-month storage period. Laboratory research was also done to understand the optimal combination of lime/ash to stored waste needed to enhance microbial inactivation.

To evaluate the acceptability of the UDDTs, quantitative surveys were carried out across 400 households of people both using and not using UDDTs. They were conducted 18 months apart to determine changes in use, condition and perceptions of the UDDTs.

What were the key findings?

• The study found that refugees in the Hilaweyn refugee camp were using the UDDTs, and that they were using them correctly and consistently. Reported satisfaction levels were significantly higher among respondents in the second survey: 97.0% of respondents were ‘mostly satisfied’ or ‘very satisfied’ with their UDDT compared to 62.8% in the first survey. Satisfaction depended on factors such as familiarity, cleanliness, and length of time to become accustomed to it. There was no significant difference in satisfaction between UDDT and latrine users.
• Biological performance evaluations found that 95% of UDDTs met World Health Organization (WHO) microbial guideline levels for safety at 12-months of storage.
• Results from the laboratory research show that the addition of lime (at 2-5% by weight) to increase pH can assist in killing microbes. This could help with safe transport and disposal and provide an additional safety measure if vault contents had to be emptied earlier than 12 months. However, the study suggested that UDDTs may not be suitable for every setting. Conditions in Hilaweyn were very hot and dry, which helped to inactivate micro-organisms. Barriers to uptake and scaling up of UDDTs in humanitarian contexts may be the initial cost, complexity, and maintenance.

What does this mean for policymakers and practitioners?

The study findings have validated and reinforced UNHCR’s use of UDDTs at Hilaweyn camp. They have inspired humanitarian agencies to consider alternative sanitation options and helped to strengthen the argument to use UDDTs in certain humanitarian contexts.

Since the study was completed, the International Rescue Committee (IRC) has constructed more UDDTs at Hilaweyn camp, and some at another location, Buramino camp.

In 2018, supported by the Bill and Melinda Gates Foundation (BMGF), Oxfam and UNHCR jointly published standard operating procedures for UDDTs, which reference the biological performance evaluation data from the study. Oxfam also updated its own standard operating procedures for refugee camps in 2020, again referencing data from the study.

In Gambella, Oxfam is now implementing a large pilot of UDDTs with support from the NRC and a further pilot of 4,000 UDDTs across five refugee camps for a UNHCR project also funded by BGMF. Given that Oxfam was a study partner and noting the updated Oxfam standard operating procedures, it can be inferred that the study contributed to the decisions made around these pilots.

Finally, the study findings informed the refinement of UDDT design and best practice implementation, for example how to best empty and store waste.