Steps for Technology Selection

Selecting locally appropriate sanitation technologies and combining them into viable sanitation systems can be complex: there are many aspects to consider and trade-offs to make. It helps to proceed in several steps. Additionally, it is an iterative process but already thinking in the first phase about the future for upgrading and hand-over. While in the initial phase, the focus is on providing safe community latrines (toilet user interfaces and on-site storage), as latrines fill up, appropriate technologies must be identified for on-site treatment, or transport and off-site treatment, safe disposal or use. Using a systematic assessment framework that includes the technology options and assessment criteria for each functional group along the sanitation chain and in different response phases, helps to eliminate inappropriate choices, consider the entire sanitation value chain and plan for incremental improvements over time.

Key Actions

1. Focus on the safe containment of faecesFaecesRefers to (semi-solid) excrement that is not mixed with urine or water. Depending on diet, each person produces approximately 50–150 kg per year of faecal matter of which about 80 % is water and the remaining solid fraction is mostly composed of organic material. Of the total… to protect human health in the immediate response.
2. Move as fast as possible from open defection to using shared latrines and on-site containments appropriate for the local context (e.g. shallow or deep trench latrines).
3. During the stabilisation phaseStabilisation PhaseThe stabilisation (or transition) phase usually starts after the first weeks/months of an emergency and can last six months or longer. The main focus is to increase sanitation service coverage and an incremental upgrade and improvement of temporary structures as well as to…, organise Emptying and Transport (as pits are filling up and desludgingDesludgingThe process of removing the accumulated sludge from a storage or treatment facility. is required) according to local skills and financial resources and consider Treatment Technologies that ensure Safe Disposal or Use Technologies.
4. Identify specific solutions for difficult contexts as described in Specific Challenging Contexts. E.g. consider raised latrines or container-based solutions that are water-tight if there is a risk of flooding, the groundwater tableGroundwater TableThe level below the earth’s surface which is saturated with water. It corresponds to the level where water is found when a hole is dug or drilled. A groundwater table is not static and can vary by season, year or usage. is high or the soil conditions do not allow pits.
5. Consider that selecting the most appropriate sanitation systemSanitation systemEffective network of people (community) and the systems of which they are a part, operating together to deliver sanitation services (IRC 2022). configuration is an iterative process.
6. Consider Inclusive Design (women, children, elderly people) and socio-cultural aspects when designing latrines (‘washers’ versus ‘wipers’).
7. Consider the interlinkages with other services: consider solid waste management and greywater managementGreywater ManagementGreywater management refers to the process of collecting, treating, and using or disposing of wastewater generated from non-toilet domestic activities, such as laundry, dishwashing, and bathing. Greywater is distinct from blackwater, which is wastewater generated from toilets… to avoid its disposal in the pits. Use positive interactions through combining collection and treatment systems.
8. Use urinals to reduce the volume of liquid entering on-site containments. UrineUrineThe liquid produced by the body to rid itself of nitrogen in the form of urea and other waste products. In this context, the urine product refers to pure urine that is not mixed with faeces or water. Depending on diet, human urine collected from one person during one year… usually does not contain pathogens and hence some infiltration is acceptable.
9. Consider potential synergies with the sanitation systems of host communities. Are there existing service providers (such as for Desludging or Mobile Toilets)?
10. Take account of subsequent phases when selecting technologies for each phase. The long-term goal (beyond the humanitarian response) is to establish sustainable sanitationSustainable SanitationSustainable sanitation aims to protect and promote human health by providing a clean environment and breaking the cycle of disease. In order to be sustainable a sanitation system has to be socially acceptable, technically and institutionally appropriate, economically viable… systems – systems that protect human health and the environment, that are technically appropriate, financially viable, socio-culturally and institutionally accepted and allow for resource recovery and reuseReuseUse of recycled water or other sanitation products. (SuSanA 2008). The development of an Exit Strategy together with the host communities and according to commonly agreed Standards crucial to guarantee the services for the future. Communities must be involved in the selection of land as early as possible: especially land for treatment is expensive, locations are controversial (nobody wants to live close to a faecal sludgeSludgeMixture of solids and liquids, containing mostly excreta and water, in combination with sand, grit, metals, trash and/or various chemical compounds. A distinction can be made between faecal sludge and wastewater sludge. Faecal sludge comes from on-site sanitation technologies,… treatment plant) and transportation distances should be optimised (see also Site Planning).

Relevance/Importance

Inappropriate sanitation or technology choices lead to misuse, a lack of ownership and resources for operation and maintenanceOperation and MaintenanceRoutine or periodic tasks required to keep a sanitation process or system functioning according to performance requirements and to prevent delays, repairs or downtime. and the failure of sanitation intervention; this has direct consequences for people and the environment.

Typical examples of inappropriate choices include flush toilets where there is no water, dry toilets where people use water for anal cleansing and flushing, pit latrines where there is a high groundwater tableGroundwater TableThe level below the earth’s surface which is saturated with water. It corresponds to the level where water is found when a hole is dug or drilled. A groundwater table is not static and can vary by season, year or usage. or no access for emptying, no space for the safe disposal of faecal sludgeSludgeMixture of solids and liquids, containing mostly excreta and water, in combination with sand, grit, metals, trash and/or various chemical compounds. A distinction can be made between faecal sludge and wastewater sludge. Faecal sludge comes from on-site sanitation technologies,… or activated sludgeSludgeMixture of solids and liquids, containing mostly excreta and water, in combination with sand, grit, metals, trash and/or various chemical compounds. A distinction can be made between faecal sludge and wastewater sludge. Faecal sludge comes from on-site sanitation technologies,… treatment when there is no energy supply or skills and finances for operation and maintenanceOperation and MaintenanceRoutine or periodic tasks required to keep a sanitation process or system functioning according to performance requirements and to prevent delays, repairs or downtime.. In addition to these technical and geophysical factors, the identification and selection of appropriate sanitationAppropriate SanitationCombination of sanitation technologies that are compatible and provide a socially and environmentally acceptable level of service at affordable cost. This can be translated into geo-physical, technical, socio-cultural, legal, financial as well as criteria concerning capacity and… technologies require consideration of socio-cultural, financial and institutional aspects as well as skills and capacities. Systematically matching technology options with these different factors (see What to Consider When Selecting Sanitation Technologies) helps practitioners to identify more appropriate options.

Overview

Technology selection always requires an initial assessment of the WASH situation. Baseline assessment and the factors to consider for technology selection are described separately.

Technology selection can happen in the following steps:

1. Identify two to three feasible system options based on the collected assessment data  and the system selection criteria (see What to Consider When Selecting Sanitation Technologies?). The Compendium of Sanitation Technologies in Emergencies provides a simple overview on technologies. SaniChoice provides an advanced technology appropriateness filter. You can also use simple guides and checklists such as those provided in OXFAM (2022) and Harvey (2007) or MacMahon et al. (2019). Key questions to ask:
2. • Assess the initial situation including the number of users, identification of the WASH practices, preferences and needs of the user groups to be served, the geographical conditions, and the institutional and regulatory environment
   • Find out what WASH infrastructure already exists and can be integrated.
   • Find out what sanitation practices the target communities are used to and evaluate if these are appropriate and can be implemented.
   • If parts of a sanitation systemSanitation systemEffective network of people (community) and the systems of which they are a part, operating together to deliver sanitation services (IRC 2022). already exist, think of whether and how to integrate them
2. Based on the initial assessment, identify the five most important criteria for technology selection along the functional groups and emergency phases (see What to Consider When Selecting Sanitation Technologies?). Key questions to ask:
3. • How much water is available and where?
   • What are the soil conditions?
   • How much space is available. onsite and off-site
   • How can facilities be accessed?
   • What kind of materials and skills are available for construction and operation and maintenanceOperation and MaintenanceRoutine or periodic tasks required to keep a sanitation process or system functioning according to performance requirements and to prevent delays, repairs or downtime. and what is their costs?
   • What are the financial resources available
3. Rank the different sanitation technologies from each functional groupFunctional GroupA functional group is a grouping of sanitation technologies that have similar functions. The five different functional groups from which technologies can be chosen to build a sanitation system include (1) the user interface, (2) the collection and storage/treatment, (3) the… according to their performance regarding the criteria (you can use a simple scale of "+", "++", and "+++")
4. Discuss the ranking with different stakeholders
5. Finalise the sanitation systemSanitation systemEffective network of people (community) and the systems of which they are a part, operating together to deliver sanitation services (IRC 2022). design by selecting a compatible set of locally appropriate sanitationAppropriate SanitationCombination of sanitation technologies that are compatible and provide a socially and environmentally acceptable level of service at affordable cost. This can be translated into geo-physical, technical, socio-cultural, legal, financial as well as criteria concerning capacity and… technologies along the five functional groupFunctional GroupA functional group is a grouping of sanitation technologies that have similar functions. The five different functional groups from which technologies can be chosen to build a sanitation system include (1) the user interface, (2) the collection and storage/treatment, (3) the…
6. Document including links to existing services with the humanitarian context or the host communities as well as potentials for upgrading in future phases.