Department Sanitation, Water and Solid Waste for Development

Sanitation technology and system choice for urban planning (SaniCHOICE)

SaniChoice open-source webtool is available at

This project aims at developing methods and tools to help researchers and practitioners including expert consultants and decision makers in answering these questions. These methods help improving current sanitation planning practice by :

  • Providing a structured and thus transparent approach to technology and system option selection
  • Making international data on different technology and system options available to the local context for more empirical decision making.
  • Enforcing the consideration of entire sanitation system by providing suitable technologies for each and every step.
  • Reducing knowledge bias by enabling the consideration of a large and broad range of technologies and systems including novel options
  • Supporting planning for more resource efficient and sustainable sanitation by revealing how different options perform regarding relevant criteria and what trade-offs to expect.



Selecting a locally appropriate and sustainable sanitation system for a given case within a city is a complex multi-criteria decision-making problem. It involves

  • A continuously growing number of technology options and corresponding system configurations;
  • Multiple criteria from all sustainability dimension including health and hygiene, environmental protection, appropriate technology, operation and maintenance, financial and economic viability, socio-cultural and institutional acceptance;
  • And many stakeholders with sometimes conflicting interests.

The problem is particularly challenging in expanding urban areas of developing countries, where most of the current population growth is taking places. In these areas, conventional sanitation systems are often not viable because they depend on expensive sewer systems, large quantities of water and energy, and stable institutions.

Moreover, the sustainable development goals challenge us to come up with better solutions that close cycles at the lowest possible level in order to protect natural resources and people downstream.

This has led to the development of many novel technologies  and system configurations such as urine diversion toilets, container-based sanitation, or decentralized wastewater treatment systems. These options are more appropriate for developing urban areas because they are independent from sewers, energy, or water and often also require less space. The innovations are also potentially more sustainable because they allow for the recovery of nutrient, water, energy resources and are more flexible to changing socio-demographical or environmental conditions. This potential has also been recognized in high-income countries like Switzerland, where the focus is on optimising aging infrastructure.

While novel technologies potentially are more appropriate and enhance resource efficiency, they also increase planning complexity. How appropriate are different technologies in a specific case ? How can they be assembled into entire systems ? And how do these systems perform for different sustainability indicators at the scale of an urban settlement ?

Expected outputs


Santiago: the SANitation sysTem Alternative GeneratOr, a software that allows to answer following questions

  • What conventional and novel sanitation technologies are currently available and how can these be assembled into entire systems ?
  • How appropriate are the technologies and systems for a specific case?
  • How to select a set of systems as input into the planning process?
  • How sustainable are the selected systems in terms of resource recovery and what are the trade-offs to other sustainability indicators?

Santiago is flexible to be applied for any (future) technology or application case.


SaniCHOICE: An open-source web-based decision-support and training tool that combines SANTIAGO with the Compendium of sanitation systems and technologies .
The aim of this tool is to provide engineers, decision-makers, planners, implementers, NGO staff and students with the information and data they need to consider novel sanitation systems and technologies when planning for locally appropriate and resource efficient urban sanitation. It makes the technology and system selection systematic, transparent, and evidence-based.


Capacity development material:

Santiago methodology: a step-by-step guideline to apply Santiago integrated in a planning process such as CLUES or Sanitation 21.

A city sanitation planning (training) toolbox that provides an overview on existing training material and tools for each step of the planning process

Training material for the dissemination of the methods and tools in own and partners’ capacity development activities

Case studies with practice partners in different cities including small town development in Nepal or housing cooperatives in Switzerland.

Research questions


Throughout the development of the outputs, several research questions will be of relevance:

  • What technologies and system configurations are currently available and how can they be assembled into entire systems?
  • How can appropriate technologies and systems be select for a given case considering the local environmental, technical, institutional, and socio-cultural conditions?
  • What is the potential contribution to sustainable development, particularly resource recovery, and environmental footprint reduction?
  • What different planning cases do currently exist and how can they be characterised?
  • What kind of information do planners (expert consultants and decision makers) need to consider the broad range of technologies, systems, and sustainability criteria in strategic planning? And how would they access this information?