Latrine, Latrine. Where are you?

3 min readAug 12, 2022

Drone-based Latrine detection with Amref Health Africa

In developed and industrialized countries, public sanitation can be something that people often take for granted. While some of the world’s population is privileged to quality sewage/septic systems and water treatment facilities, the majority is not. According to the World Bank, “only 33% of Sub-Saharan Africa’s population has access to basic sanitation and 220 million people across the continent still practice open defecation — in some countries, this number is increasing, as service providers fail to keep pace with population growth.” Poverty, increased pollution, and a lack of resources have been some of the major barriers influencing the water/sanitation crisis in sub-Saharan Africa. A lack of quality sanitation systems doesn’t just result in a lack of cleanliness, it goes beyond sanitation and water quality, it’s about the safety of women and the all-around wellbeing of those who call Africa their home.

Since its humble beginnings in 1957, Amref Health Africa has been on a mission to improve the lives of disadvantaged people in Africa by bridging the gaps between communities, health systems, and governments. As a leading force of advocacy for health system reforms in Africa, Amref Flying Doctors, along with Waste and Aqua for all are working in the FINISH Mondial program with governments, communities, businesses, and financial institutions, to create a sustainable sanitation market in Kenya, Uganda, Tanzania, and Ethiopia.

In order to do so, Amref Flying Doctors, collaborated with Space4Good to leverage earth observation technology to detect and count sanitation structures in selected areas of interest in Uganda. By doing so, they can see the density of these infrastructures, run the program to facilitate the market and the development of new ones, and check the impact after the end of the program.

Figure 1. Amref visiting the Space4Good office.

To find the most suitable pipeline, Space4Good developed and tested various deep learning-based methodologies resulting in an extensive mapping of latrines using UAV high-resolution imagery. Two main approaches were tested segmentation and object detection. Using the labels created manually, the chosen model reached a precision of 87% and a recall of 79%. The predicted points were then vectorized and the heat map was created. Considering that it can be very hard to distinguish some of the latrines due to the lack of distinguishing features or tree cover even for the human eye, these results are upstanding. The final results can be filtered according to the level of confidence desired.

Figure 2. Latrine prediction examples.

This proof of concept for Uganda proved the feasibility of the applied remote sensing methodology developed by Space4Good and it will lead to more efficient, applicable, and targeted planning and intervention processes in the sanitation market. To expand the partnership into further areas, Space4Good and Amref are looking to analyze and allocate more resources for the data retrieval (as well as to iteratively improve the methodology even further) to better locate latrines, retrieve distribution info and facilitate programs in areas with sub-optimal sanitation.

In addition to proving the capabilities of remote sensing for critical infrastructure identification, Amref along with knowledge from Space4Good has showcased that there is a seemingly endless array of possibilities and benefits brought forth by earth observation. A big thanks to all of those who made this project possible, and to those continuing to help facilitate and boost the integration of better and safer sanitation systems within Africa.

Would you like more information or are you interested in collaborating with Space4Good? Visit our website or contact us via




Space4Good is our name and driving force: leveraging space technology to support impactful, inspirational projects and change-makers around the world.