Department Sanitation, Water and Solid Waste for Development


Sandec conducts projects worldwide in close collaboration with international and local partner organisations. These projects contribute to increasing the research capacity and professional expertise in the partner countries, and are part of the work of our five research groups:


Strategic Environmental Sanitation Planning

Research Projects

Municipal Solid Waste Management

Research Projects

Black Soldier Fly Biowaste Processing
Organic waste sources have a high nutritional potential and thus make an excellent feed substrate for insect larvae of the black soldier fly (BSF), Hermetia illucens. These larvae are able to reduce the waste by 50-80% and convert up to 20% of the waste into larval biomass within ±14 days.

SWIFT-Sustainable Waste-based Insect Farming Technologies in Uganda and Malawi
SWIFT is an innovative and transdisciplinary R&D project funded by the Swiss National Science Foundation and the Swiss Agency for Development and Cooperation (SDC) under the Solution Oriented Research for Development Programme (SOR4D)

Amplifying Waste Recovery Solutions – Towards a Circular Society (AWARE)
WARE is an applied research project that develops and validates methods focusing on plastics management and on strengthening the circular economy. Implemented in the Phu Yen province in Vietnam, the project will contribute towards better understanding of 1) assessment of plastic sinks and pollution for a city or watershed, 2) socio-psychological measures to enhance participation and behaviour change towards more circular waste management practices, and 3) appropriate technologies for recycling of mixed plastic fractions.

Zero Waste Schools and Communities
Zero Waste at Schools (ZW@S) develops and validates methods to foster integrated strategies and technologies leading to a “zero-waste” approach at school level.

SDG monitoring of solid waste collected and managed in controlled facilities
In collaboration with UN-Habitat and Wasteaware, this applied research project develops a systematic approach to measuring the SDG indicator 11.6.1 “Proportion of municipal solid waste collected and managed in controlled facilities”

Waste Flow Diagram (WFD)
In collaboration with GIZ, the University of Leeds and Wasteaware, this research project develops and validates a rapid and observation-based assessment to quantify and map plastic leakage from municipal solid waste management systems

Carbonization of Urban Bio-waste
Carbonization is a process during which biomass is heated in the absence of oxygen; the primary goal is to produce char. This char can be further processed into briquettes and used as household cooking fuel. The objective of our research on slow pyrolysis and hydrothermal carbonization (HTC) is to explore the potential of using organic waste to generate a char product that has a value in the local market as a replacement for wood-based charcoal and thus, could be a financial driver of organic waste processing businesses.

SOWATT - Selecting an Organic Waste Treatment Technology
This project provides decision support to help structure and assist in the process of comparing and selecting the most promising biowaste treatment options for a given case study.

Anaerobic digestion of organic solid waste
Besides composting or direct animal feeding, anaerobic digestion (biomethanation) of organic solid waste is considered a promising treatment option for this particular waste fraction. Anaerobic digestion converts biomass into energy (biogas). Biogas – a mixture of CO2 and methane (CH4) – can be used as a renewable energy source for cooking, lighting or to generate electricity, thereby replacing other fuel sources. Biogas digestate is a nutrient-rich fertiliser that can be applied in gardens or agriculture.

Decentralised composting
The existing physical plan and socio-economical situation of many cities in low and middle-income countries strongly favours the implementation of decentralised composting systems. Decentralised composting is less technology dependent, using locally available materials and simple technology. Our research on composting includes co-composting of organic waste and faecal sludge as well as market demand for compost from organic waste.

Management of Excreta, Wastewater and Sludge

Research Projects

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

Completed Projects

Water Supply and Treatment

Research Projects

Evaluation of a locally constructed in-line chlorination technology for piped water supplies in rural Guatemala
Access to safe drinking water continues to be a challenge in low- and middle-income countries, especially in rural areas. In the context of the Lake Atitlán region of Guatemala, high rates of diarrheal disease indicate pressing need to improve the quality of the water supplies. Low-cost in-line chlorination technologies for passive, automatic disinfection have great potential for achieving sustained treatment of small rural drinking water systems with limited technical and managerial capacities. However, little evidence exists on the effectiveness of these novel chlorination technologies when implemented at program-scale, particularly in a rural context. Eawag is collaborating with Helvetas Swiss Intercooperation Guatemala on the project ETH4D Research Challenge: Chlorination Interventions for Rural Supplies. Using a mix-methods approach, this project aims to systematically evaluate the applicability of a locally constructed in-line chlorination device (A’Jin chlorinator) designed by Helvetas for use in piped systems served by the RU’K’UX YA’ program in the Lake Atitlán region of Guatemala.


REACH: Establishing a Drinking Water Security Strategy for Rural Nepal
In rural Nepal, 92% of households have access to an improved drinking water source. Yet assessments of microbial contamination in Mid-Western Nepal shows that 70 - 80% of taps are not delivering water that is safe for drinking. Achieving Sustainable Development Goal Target 6.1 (SDG 6.1), to deliver “universal and equitable access to safe and affordable drinking water for all,” is especially challenging for remote rural settings facing multiple obstacles. These include unreliable supply chains for sampling materials, the high cost of laboratory equipment, and unreliable or non-existent access to electricity.


Participatory Action for Long-Term Arsenic-Safe Water (PACT)
This health related behaviour change research focuses on the prevention of arsenicosis and prevention of diseases caused by microbial contamination of drinking and cooking water in Bihar, India. Many safe water mitigation options exist, but most of the community based infrastructure is functional and not used. Combined, intervention on psychological ownership and habitual behaviour can lead to a long-lasting functionality and sustainable use of the safe water infrastructure. The effectiveness and the way how these concepts change peoples behaviour through psycho-social factors are subject to this research. The project takes place in Arsenic-affected areas of Bihar.


SMALL: Water Supply and Sanitation Service Provision in Small Town at the Urban-Rural Intersection
Project SMALL aims to support the development of applicable and sustainable water and sanitation provision models for small towns in Sub-Saharan Africa. Practice and research have traditionally focused either on distinct urban centers or rural communities. However, areas under transition, including small towns throughout Uganda and Mozambique, do not easily fit the definitions used by rural or urban planners. Small towns therefore lack clear guidance on applicable water and sanitation service models and, as a result, suffer from poor progress in expanding access to safely managed water and adequate sanitation. This project aims to identify and account for the specific needs, opportunities and challenges of transition zones in Uganda and Mozambique when devising improved service provision models, focusing on the experiences of the National Water and Sewerage Corporation (NWSC) and the Administração de Infraestruturas de Abastecimento de Água e Saneamento (AIAS).


Evaluation of Open Defecation Free (ODF) Toilets in Flood-Prone Regions of Nepal
The concept of Open Defecation Free (ODF) zone started with the introduction of Community-Led Total Sanitation (CLTS) in Nepal. From 2000 to 2010, sanitation coverage in Nepal has improved from 27% to 43% due to the introduction of sanitation initiatives like ODF movement and this coverage further increased to >97% in 2019. On September 30, 2020, all 77 districts in Nepal were declared free from open defecation. However, there are several reports about the sub-par quality of the constructed toilets in Terai districts, which raises questions about its long-term sustainability. Furthermore, extreme weather events like flooding, which is quite common in the region, pose further risks. Flooding events can make toilets partially or completely unusable, forcing the residents to open defecate in the fields. Overflowing of the pits or leaching of fecal matters in the groundwater also can cause diarrheal diseases outbreak during such events. Therefore, the provision of suitable and safe sanitation facilities that are low cost and socially and culturally acceptable still remain a challenge in flood prone regions. This study will focus on three main districts in the Terai region, Rautahat, Sarhali, Sunsari and Jhapa to conduct a study to evaluate the sustainability of the constructed toilets in the flood-prone regions.   


Sanitation Policy Brief for pan-European Region
Sandec will provide consultancy service to World Health Organization (WHO) European Centre for Environment and Health to develop a sanitation policy brief for the pan-European region. The policy brief for the pan-European region is intended to provide a clear pathway to understand the challenges requiring urgent attention and action in the region's sanitation sector. The brief with summarise the sanitation situation in the region, explore the current and emerging sanitation challenges, advocate for financing in sanitation and outline potential climate change adaptation options for strengthening climate resilience of sanitation governance, policies, and systems and services.


Adapting Water Quality Testing Tools and Methods
The demand for water quality testing is rising globally, driven by efforts to meet SDG 6’s drinking water targets and, more generally, a growing awareness of widespread contamination of drinking water supplies of all types. However, access to the equipment, materials and logistical support needed for routine monitoring remains concentrated in urban centers, with slow diffusion of even basic water testing tools to non-urban areas. Our research in this area aims to test and adapt materials, equipment and laboratory protocols, with an emphasis on overcoming the major technical, logistic and financial barriers that impede local uptake.


Identifying factors contributing to sustained functionality of water supply infrastructure
As efforts to rapidly expand access to drinking water supplies intensify under SDG 6, concerns have been raised about the risks of wasted investments and poorly maintained projects. The WST group's research on system functionality aims to inform program managers and national governments concerned with ensuring the longevity of water infrastructure. These studies rely on variable-oriented designs and moderate to large sample sizes to identify factors determining project outcomes.

Compendium: Drinking Water Systems and Technologies from Source to Consumer
The Compendium combines and discusses the entire range of drinking water technologies, approaches and concepts relevant for rural, peri-urban and urban contexts in a single concise and well-structured document. It is a comprehensive and user-friendly manual that supports decision making for developing drinking water supply and treatment systems in the context of the global south. Technologies from six functional groups build drinking water systems applicable for different water sources, scales and contexts. The two-page information sheets developed for each technology provide major design, O&M considerations and key decision criteria. They link the choice of the technologies to key aspects of the enabling environment and crosscutting issues.


Evaluating Household Water Filters for Use in Emergency Contexts
Point-of-use water treatment is essential for ensuring the safety of drinking water during humanitarian emergencies. Over nine months an interdisciplinary team conducted a comparative analysis of five water treatment devices in emergency contexts in Palestine, Kenya and Somalia. Filters were assessed in terms of technical performance, acceptance and consistency of use. Based on the study results, the team delivered recommendations to manufacturers for filter design modifications to improve the suitability of household water filters for vulnerable populations.


Hybrid Coagulation-Ultrafiltration
Ultrafiltration (UF) is a promising technology for decentralised water treatment in developing countries; yet, a major hindrance to long-term operation of UF is membrane fouling. This leads to permeate flux losses, increased membrane cleaning routines and high operating costs. Several researchers have studied coagulation pre-treatment of feed water to overcome fouling, but little research exists on surface water sources characterised by the concentrated organic and inorganic matter content found throughout Uganda. This study examined the performance of a UF system for drinking water treatment, using polyaluminium chloride (PACl) coagulant for fouling control


Multiple-use Water Services Impact Evaluation
People living in poor rural areas need water for domestic and productive activities. Multiple-use water services (MUS) is an integrated water service delivery approach that takes into account households’ range of water needs as the starting point when planning, financing, and managing water supply services for rural communities.


Water-Energy-Environment (3E) Programme
The Water-Energy-Environment (3E) programme was launched in 2012 with funding support from the Swiss Agency for Development Cooperation (SDC), with the aim to support scientific partnerships between the International Institute for Water and Environmental Engineering (2iE) of Ouagadougou, Burkina Faso, and Swiss universities and institutes (EPFL, HEIG VD and EAWAG).

Water Safety Management

Research Projects 

Gravity Driven Membrane Filtration (GDM) – The GDM technology uses the gravity pressure of water and ultrafiltration membranes to treat microbiologically contaminated water. We are assessing the performance of different configurations and implementation models for drinking water treatment using GDM at household or community level. Together with our partners, we have developed a practical user guide for the GDM technology and a video series, explaining the technology, key concepts and operation and maintenance procedures.


Strategies to reduce the recontamination of water during transport and storage - Water managed in hygienically critical environments is at high risk to being recontaminated during transport and storage. We are therefore experimenting with different approaches to enhance safe storage such as secondary disinfection using UVC LEDs in storage containers, evaluation of passive low-cost chlorination approaches at the point of delivery, assessment of cleaning strategies for water containers and the development of improved water transport containers.


Urban Water Flow Diagram - We are developing a tool to visualize urban water flows, the “urban Water Flow Diagram” to facilitate integrated urban water management. The tool will give an overview of the local urban water situation in a snapshot by visualizing the major water flows from source to discharge together with a judgement for every flow, whether the management practices are appropriate or problematic.


Evaluating automated chlorination for drinking water treatment using on-site production of chlorine - Lacking supply chains and unreliable access to chlorine products are an obstacle for the continuous operation of automated drinking water disinfection approaches using chlorine. In this project we therefore assessing locally produced low-cost automated systems for in-line chlorination that use salt, water and electricity for operation. We are further developing the systems, evaluating their performance, robustness and impact on water quality at different points of distribution and the impact of their implementation on hygiene and health in the local community.


Completed Research Projects


Changes in water treatment, hygiene practices, household floors and child health before and during the Covid-19 pandemic in Nepal- During this project we conducted cross-sectional surveys in Surkhet, Accham and Dailekh Districts Nepal, before and during the Covid-19 pandemic to assess the impact of water safety interventions and hygiene training implemented before and during the pandemic on WASH conditions and practices and to assess the association of these changes with child health.


Assessing the impact of carrying water on women’s health - Improved access to safe drinking water and sanitation are important determinants of human health. This project is assessing women’s health burden associated with transporting water from community water points to their homes.


Production and Marketing Models for Ceramic Water Filters – this project assessed challenges for production and marketing of ceramic water filters in Nepal and carried out marketing trials for ceramic water filters in Kenya and Bolivia to to assess the influence of the different stakeholders responsible for community education and operation of distribution and retail sales, as well as different payment in installment options on product sale and willingness to pay for ceramic water filters.


Solar Water Disinfection (SODIS) – is a simple low-cost method for drinking water treatment at household level using PET-bottles and solar radiation for disinfection. We supported the development and spread of the SODIS method through research in microbiology, health impact, material assessments, behaviour change strategies and global promotion activities.  SODIS Website.