Department Sanitation, Water and Solid Waste for Development

Management of Excreta, Wastewater and Sludge (MEWS)

The research group Management of Excreta, Wastewater, and Sludge (MEWS) addresses solutions for city-wide inclusive sanitation (CWIS) through applied and fundamental research, design and optimization of treatment technologies, development of analytical and monitoring methods, and training and reference materials. The goal of city-wide inclusive sanitation is equitable, safe, and sustainable sanitation for everyone. The development of management solutions for the entire service chain are essential to fulfill the sanitation needs of urban areas, including containment, collection, transport, treatment, and resource recovery, and will vary depending on the associated infrastructure. Access to safely managed sanitation can be achieved through the implementation of a range of appropriate technologies tailored to the realities of rapidly growing cities, with integrated combinations of sewered and non-sewered, off-grid, and decentralised and centralised technologies. One third of the world’s population currently relies on non-sewered sanitation, predominantly in low- and middle-income countries, with only a fraction safely managed. There is an urgent need to find immediate solutions to bridge this gap, while in parallel researching more globally relevant and sustainable solutions for the future.

Faecal sludge (FS) is defined very broadly as what accumulates in onsite sanitation technologies and specifically is not transported through a sewer. It is composed of excreta, but also anything else that goes into an onsite containment technology, such as flushwater, cleansing materials and menstrual hygiene products, greywater (i.e. bathing or kitchen water, including fats, oils and grease), and solid waste. The importance and need for faecal sludge management (FSM) has been recognised worldwide, with rapidly occurring developments. Other possibilities for non-sewered sanitation include community scale solutions, emergency and humanitarian settings, and even co-treatment with sewered sanitation. Off-grid solutions include the reinvent the toilet challenge, in-building treatment in urban areas, and on property treatment in rural areas. Non-sewered sanitation can provide more sustainable options, however, there are major gaps in fundamental, scientific knowledge, applied research to scale-up solutions, standard methods for monitoring, design, and analysis, and reference materials. To address these gaps, our research has a focus on development of innovative but practical and reliable solutions, along with the resources that will allow practitioners to integrate management solutions into city-wide inclusive sanitation.


Ongoing Research Projects

MEWS researches fundamental mechanisms governing dewatering and settling in faecal sludge to gain insights for improved FSM.
The Volaser measuring device measures in situ volumes of faecal sludge in order to estimate Q&Q.
Smart phone app that can predict characteristics of faecal sludge.
Measures for monitoring need to be in place to ensure adequate protection of public health, and to evaluate progress towards achieving SDGs.
Sustainable management requires estimates of the Q&Q that are accumulating at community to city-wide scales.
The provision of adequate sanitation at every step of a crisis is crucial in order to protect human and environmental health.
Resource recovery, market based approaches, and business models, are key to sustainable management.
MEWS conducts applied research to push technologies from innovative and transferring, to technologies that are field-ready for implementation.

Training Material and Key Resources

FSM Book

WHO Guidelines

Highlights and Exercises


Methods book



Past Research Projects

Sandec is working in collaboration with the Hanoi University of Civil Engineering to evaluate the feasibility of treating faecal sludge through anaerobic digestion
The SEEK project aims to increase revenue potential by processing sludge together with other urban waste streams into fuel pellets and electricity through gasification.


Nienke Andriessen Project Officer Tel. +41 58 765 5082 Send Mail
Michael Vogel Tel. +41 58 765 5944 Send Mail
Kelsey Shaw Tel. +41 58 765 5551 Send Mail
Kayla Coppens Tel. +41 58 765 6717 Send Mail
Ednah Kemboi Tel. +41 58 765 6860 Send Mail

Nida Maqbool

Tel. +41 58 765 55 53