Water purification denotes the process of making water safe for human consumption, but the term is also used for other cleansing processes to make water suitable for e.g. industrial or agricultural uses (see also water use Africa). To make water safe for human consumption, contaminants such as organic material, pathogens or chemical substances have to be removed from raw water (see also pathogens and contaminants).
Water purification should combine both software (behavioural change, e.g. invalid link) and hardware approaches (technologies based on physical, chemical or biological processes, e.g. slow sand filtration).
Some of the most relevant software tools for water purification in the Sub-Saharan Africa region are described below: invalid link, media campaigns, and the invalid link. Moreover, you will find an overview on some of the most relevant hardware tools for water purification in the Sub-Saharan Africa region such as solar water disinfection, chlorination, biosand filters and boiling.
At the end of this factsheet, you will also find an overview of tools. An exhaustive collection of software and hardware tools for water purification can be found in SSWM Water Purification Implementation Tools.
Social Marketing
invalid link is the use of commercial marketing techniques to promote the adoption of behaviour that will improve the health or well-being of the target audience or of a society as a whole. CARE Kenya, for example, uses a combined social marketing/community mobilisation approach to successfully implement the Safe Water Systems (SWS) in rural communities in Western Kenya, Kenyan clinics and schools. Program results show that over a third of the target population adopted the SWS disinfectant solution in less than six months (MAKUTSA et al. 2001). A cost analysis of a social marketing initiative for “Clorin” brand product sold in bottles in Zambia shows that if the bottle price increased to $0.18, the project would be self-sustaining at maximum capacity. The analysis, which considers production, marketing, distribution, and overhead costs of “Clorin” before and after sales reached nationwide scale and sales revenue, demonstrated that efficiencies in the SWS supply chain can be achieved through social marketing. Even with a subsidy, overall program costs per beneficiary are low (BANERJEE et al. 2007).
Media Campaigns – Poster and Flyers
Posters and flyers (see also invalid link) are commonly applied to penetrate Safe Water System (SWS) products such as WaterGuard, PUR and Aquatab, etc. in the context of water treatment marketing and outreach/community mobilisation activities to the vulnerable population in Sub-Saharan Africa (see also invalid link). In Kenya for example, the Linda Kila Tone campaign ran during the last quarter of 2008. It sought to dispel the assumption that clear water is safe to drink, a key barrier to adopting point-of-use (PoU) water treatment. The campaign encouraged caregivers to “guard every drop.” In 2009, the program aired diarrheal disease prevention campaign radio spots (see also invalid link) as part of a broader child health campaign in Kenya. The Malezi Bora initiative ran for two two-week “bursts” in May and November and sought to increase health-seeking behaviours. Integrating messages on PoU water treatment into the broader campaign ensured water treatment as a key child health message and practice (PSI n.y.).
Developing Human Resources
The invalid link is at the core of sustainable development. People and communities that are empowered with the necessary knowledge and skills will be the architects of their own development and able to confront a diverse set of challenges in a rapidly changing social, economic and environmental landscape. A study of human resource development requirements in five countries – amongst them Mali, South Africa and Zambia – identified (amongst others) the following common human resource deficiencies in the drinking water, sanitation and hygiene promotion (WASH) sub-sectors:
- inappropriate trainings: often recently qualified people lack some important competences that are needed to work in the WASH sector,
- transition from academia to the work environment: there is inadequate support for the transition from academia to the work environment,
- lack in work experience: there is a lack of opportunities to get practical WASH related work experience,
- gender inequalities: in general there is a low level of women graduates from universities especially from technically oriented courses,
- training of semi-skilled/unskilled technicians: formal vocational training are missing often and water and sanitation services are provided by semi-skilled or unskilled workers that acquire practical skills informally as apprentices or from members of their family (IWA 2011).
Chlorination
Chlorination of drinking water within the drinking water network (see also centralised chlorination) or at the point-of-use (POU chlorination) is common practice in many Sub-Saharan African countries. It is for example used in Angola, Cameroon, Ethiopia, Guinea, Kenya, Madagascar, Malawi, Mozambique, Nigeria, Rwanda, Tanzania, Uganda, and Zambia (PELETZ & MAHIN 2009). The city of Cape Town, South Africa, for instance adds chlorine to drinking water to ensure the prevention of bacterial re-growth in holding water reservoirs and the network of pipes that transport water from treatment plants to homes (CITY OF CAPE TOWN n.y.) (see also prevention of recontamination). In Kenya, an innovative dispenser system has achieved remarkable and sustained use. The dispenser is filled with dilute chlorine and placed near a communal water source, allowing individual users to treat their water with the correct dose of chlorine in their jerry cans after it has been collected from the source (IPA 2011). A similar approach has been developed by the Swiss organisation (see ANTENNA 2010)in Burkina Faso, Cameroon, Kenya, Guinea, Mali, Mozambique, and Rwanda: a special device producing chlorine solution from salt (see also WATASOL) is placed in water kiosk (see also water vendors and health posts from where it is distributed/sold directly or used to pre-treat drinking water for the population around.
Solar Water Disinfection
Solar water disinfection (SODIS) is a simple point-of-use water treatment technology that is applied at household level to improve the microbiological quality of drinking water with solar radiation. This approach is particularly adapted to regions which strong solar radiation. It is applied in many Sub-Saharan African countries such as Angola, Burkina Faso, Cameroon, Democratic Republic of the Congo, Ethiopia, Ghana, Kenya, Mozambique, Senegal, Sierra Leone, Tanzania, Togo, Uganda, Zambia, and Zimbabwe (SODIS 2012a, PELETZ & MAHIN 2009). SODIS is e.g. implemented in the context of the Safe Water School project in Kenya covering 30 schools in Kisumu and Nairobi. In the Nyalenda and Manyatta slums of Kisumu, the project collaborates with 20 public primary schools totalling about 25,455 pupils. In Nairobi, the capital city of Kenya, 10 public primary schools with some 12,673 pupils are participating in the Safe Water School project (SODIS 2012b). Because the SODIS process is dependent on short radiation, which is partly attenuated by the presence of clouds, dust or turbid water, solar pasteurisation may be an alternative.
Biosand Filter
Biosand filters (BSF) are a small, household sized adaptation of slow sand filters, with the advantage that they can run intermittently. This technology has been successfully applied in several Sub-Saharan countries, such as: Cameroon, Ethiopia, Kenya, Namibia, Niger, Nigeria, Sudan, Tanzania, Uganda, Zambia (PELETZ & MAHIN 2009).
Boiling
Boiling is considered the world’s oldest, most common, and one of the most effective methods for treating water. If done properly, boiling kills or deactivates all bacteria, viruses, protozoa (including cysts) and helminths that cause diarrheal disease (CAWST 2012). The rates of water boiling vary regionally – 90.6 percent of households in Indonesia boil, whereas only an average of 4.5 percent use this technique across 22 African countries. Within Africa, the range is still high in those countries that have been studied - with 39.8 percent in Uganda, while almost non-existent in some of the other countries (ROSA & CLASEN 2010). In South Africa, for example, boiling (ca. 51%) and chemical treatment (ca. 42%) are the most commonly used treatment methods among rural households having unclean drinking water sources and treating their water (ANDERSON et al. 2011).
Awareness of Water Pollution as a Problem and the Decision to Treat Drinking Water Among Rural African Households with Unclean Drinking Water: South Africa 2004-2005
Safe Water Treatment
Cost and Financial Sustainability of a Household-based Water Treatment and Storage Intervention in Zambia
This is a study to assess the potential sustainability of the Safe Water Systems (SWS). An analysis of costs was carried out in Zambia for the “Clorin” brand product sold in bottles sufficient for a month of water treatment at a price of $0.09. This analysis demonstrated that efficiencies in the SWS supply chain can be achieved through social marketing.
BANERJEE, A. ; MCFARLAND, D.A. ; SINGH, R. ; QUICK, R. (2007): Cost and Financial Sustainability of a Household-based Water Treatment and Storage Intervention in Zambia. In: Journal of Water and Health: Volume 5 , 385-394. URL [Accessed: 17.10.2012]HWTS Fact Sheets – Detailed
This document is a compilation of Household Water Treatment and Safe Storage (HWTS) factsheets providing detailed information on various source protection, sedimentation, filtration, disinfection and safe storage processes/measures such as settling, natural and chemical coagulants, straining, biosand filter, candle filter, boiling, chlorination, SODIS, solar pasteurization, safe storage, etc.
CAWST (2012): HWTS Fact Sheets – Detailed. Calgary, Alberta: Centre for Affordable Water & Sanitation Technology URL [Accessed: 26.09.2012]Drinking Water Quality
SODIS Projects - Africa
Safe Water School
Chlorine Dispensers for Safe Water
Meeting the Water and Sanitation Millennium Development Goals
Influencing Household Water Treatment Behaviors
Challenges in Implementing a Point-of-Use Water Quality Intervention in Rural Kenya
Effectiveness of Different Household Water Treatment Approaches for People Living with HIV/AIDS in Africa
Assuring Rural Access to Water Treatment Products in Kenya’s Coast Provinces
Estimating the Scope of Household Water Treatment in Low- and Medium-Income Countries
Safe Water Systems for the Developing World
This manual was developed for program managers, technical staff, and other organisation personnel who would be involved in implementing a project to improve water quality. The manual is designed to take people through the necessary steps to initiate the planning process, assemble a team, decide between various water treatment and storage options, and devise strategies for distribution, cost recovery, promotion, behaviour change, and monitoring and evaluation.
CDC CDC (n.y): Safe Water Systems for the Developing World. A Handbook for Implementing Household-Based Water Treatment and Safe Storage Projects. Atlanta: CARE/CDC Health Initiative URL [Accessed: 02.10.2012]Modification of a Biosand Filter in the Northern Region of Ghana
This master thesis designs, pilot tests and evaluates modified local plastic design (LPD) biosand filters for treatment of highly turbid water in northern Region of Ghana.
KIKKAWA, I. (2007): Modification of a Biosand Filter in the Northern Region of Ghana. Cambridge, MA: Massachusetts Institute of Technology (MIT) URL [Accessed: 25.09.2012]Best Practices in Social Marketing Safe Water Solution for Household Water Treatment
This paper synthesises lessons learned, best practices, successes, and challenges of social marketing safe water solution, and discusses how these lessons may be applied to planning safe water treatment programs around the globe.
POUZN (2007): Best Practices in Social Marketing Safe Water Solution for Household Water Treatment. Lessons Learned from Population Services International Field Programs. Point-of-Use Water Disinfection and Zinc Treatment (POUZN) URL [Accessed: 20.09.2012]Monitoring Effective Use of Household Water Treatment and Safe Storage Technologies in Ethiopia and Ghana
This thesis offers a consistent framework for the operational monitoring of effective use of a set of eight Household Water Treatment System (HWTS) technologies including dilute bleach solution, Aquatabs, solar disinfection (SODIS), cloth filters, the ceramic pot filter, the biosand filter, PUR and associated safe storage practices.
STEVENSON, M.M. (2008): Monitoring Effective Use of Household Water Treatment and Safe Storage Technologies in Ethiopia and Ghana. URL [Accessed: 20.09.2012]Safe Water School-Training Manual
This manual, developed for primary schools in developing countries, is a working tool for teachers, school directors and school staff to turn schools step-by-step into safe water schools.
SUTER, F. (2011): Safe Water School-Training Manual. SODIS & Antenna Technologies Foundation URL [Accessed: 20.09.2012]A Planning Framework to Position Rural Water Treatment in South Africa for the Future
This report compiles the findings of a consultancy project that was undertaken to study the factors impacting on rural water treatment in South Africa. It proposes adaptive strategies to address these impacts, and develop a planning framework that can be used to position rural water treatment for the future.
SWARTZ, C.D. (2009): A Planning Framework to Position Rural Water Treatment in South Africa for the Future. Gezina: Water Research Commission URL [Accessed: 20.09.2012]Status of National Household Water Treatment and Safe Storage Policies in Selected Countries
This report assesses the status of national Household Water Treatment and Safe Storage (HWTS) policies and regulations and progress towards the global policy targets. The report details responses from a survey – amongst others in many Sub-Saharan Africa countries - and categorises countries into three tiers of readiness to scale-up HWTS.
WHO (EDITOR) (2012): Status of National Household Water Treatment and Safe Storage Policies in Selected Countries. Results of global survey and policy readiness for scaling up. Geneva: World Health Organisation (WHO) URL [Accessed: 20.04.2018]Household Water Treatment and Safe Storage Implementation Case Study
This document provides information on three case studies on household water treatment and safe storage (HWTS) projects. The Kenyan case study describes a project that - as per August 2011 - had implemented more than 1,800 bio-sand filters in two main areas in rural communities around the towns of Kisii and Eldoret.
CAWST (2011): Household Water Treatment and Safe Storage Implementation Case Study. Biosand Filters. Alberta: Center for Affordable Water and Sanitation Technology (CAWST) URL [Accessed: 25.09.2012]The Safe Water System Project - Social Marketing and Community Mobilization in Kenya
This short document reports on successful social marketing interventions, creating demand for Safe Water System (SWS) products such as a bottle of sodium hypochlorite solution branded as ‘WaterGuard’, PUR and Aquatabs in Kenya.
CDC (2012): The Safe Water System Project - Social Marketing and Community Mobilization in Kenya. Atlanta: Centers for Disease Control (CDC) URL [Accessed: 26.09.2012]The Safe Water System Project - Working with Local Health Care Staff in Kenya
This short document reports on an intervention that proved effective in linking a socially marketed health product with local information that encourages and increases adoption of the Safe Water System (SWS) and hand washing knowledge in vulnerable populations by training nurses at local health clinics to educate their clients about the importance of safe water and proper hand washing techniques.
CDC (2012): The Safe Water System Project - Working with Local Health Care Staff in Kenya. Atlanta: Centers for Disease Control (CDC) URL [Accessed: 26.09.2012]The Safe Water System Project - Safe Drinking Water and Hygiene in Kenyan Schools
This short document reports on a school-based safe drinking water and hygiene intervention. Locally produced dilute chlorine solutions that were socially marketed by a non-governmental organisation were used combined with hand washing education in 45 rural primary schools in Nyanza Province, western Kenya.
CDC (2012): The Safe Water System Project - Safe Drinking Water and Hygiene in Kenyan Schools. Atlanta: Centers for Disease Control (CDC) URL [Accessed: 26.09.2012]SODIS - Water Quality improvement at Household Level. A case example from Kenya
LEAD, a local women’s organisation, promotes SODIS for the treatment of drinking water at household level, making use of its existing network of sangams (women self-help groups). In addition, teachers and students of local schools are trained. For the supply of PET-bottles, a micro-credit system was implemented.
EAWAG/SANDEC (n.y): SODIS - Water Quality improvement at Household Level. A case example from Kenya. (= SODIS Project Case Study ). Kenya: EAWAG/ SANDECWater Purification in Rural South Africa
This paper presents a sustainable development project to address water problems in a village in the Venda region of the Limpopo Province, South Africa. The authors present the design and constructed process for a slow sand filtration system intended to provide clean drinking water to most households in the community. They present and analyse successes, failures, and ethical dilemmas encountered throughout project execution.
HARSHFIELD, E. ; JEMEC, A. ; MAKHADO, O. ; RAMARUMO, E. (2009): Water Purification in Rural South Africa. Ethical Analysis and Reflections on Collaborative Community Engagement Projects in Engineering. In: International Journal for Service Learning in Engineering: Volume 4 , 1-14. URL [Accessed: 20.09.2012]SODIS - Water Quality Improvement at Household Level. A Case Example From the Kibera Slum, Nairobi, Kenya
This document outlines that the drinking water sources in the Kibera Slum in Nairobi are of very bad condition. It contains information about Kenya Water for Health Organization (KWAHO) and its implementation of a Solar Water Disinfection (SODIS) project.
KWAHO (n.y): SODIS - Water Quality Improvement at Household Level. A Case Example From the Kibera Slum, Nairobi, Kenya. Nairobi: EAWAG / SANDEC URL [Accessed: 16.05.2019]Safe Water Systems: An Evaluation of the Zambian CLORIN Program
This evaluation report provides the findings and key lessons learnt from assessment study conducted in Zambia for the use of chlorine solution.
OLEMBO, L. FAD, K. TUBA, M. BURNHAM, G. (2004): Safe Water Systems: An Evaluation of the Zambian CLORIN Program . URL [Accessed: 31.05.2010]The Chlorine Dilemma
In this report, an extensive ethical and technological reflection on the use of chlorine as a disinfectant of drinking water is performed. Two cases are particularly investigated: the first being the choice of disinfectant in the Netherlands, a country renowned for its high standards in drinking water quality and its progressiveness in the application of novel techniques. The second case concerns the choice of disinfectant in Kenya, a developing country dealing with water shortages and especially a lack of safe drinking water. Moreover, the country can serve as an exemplary case for other countries in the same region (sub-Saharan Africa).
TUE (2011): The Chlorine Dilemma. Final Report. Eindhoven: Eindhoven University of Technology (TUE) URL [Accessed: 20.09.2012]Poster Biosand Filter
This is a poster-sized cross section through a biosand filter.
CAWST (2010): Poster Biosand Filter. URL [Accessed: 26.09.2012]Puzzle Biosand Filter Part 1
Puzzle parts of a biosand filter.
CAWST (2010): Puzzle Biosand Filter Part 1. URL [Accessed: 26.09.2012]Puzzle Biosand Filter Part 2
Puzzle parts of a biosand filter.
CAWST (2010): Puzzle Biosand Filter Part 2. URL [Accessed: 26.09.2012]SODIS in Zambia
This video explains the concept of Solar Water Disinfection (SODIS) based upon a project implemented in Lusaka, Zambia.
EAWAG (2009): SODIS in Zambia. Keepers Zambia Foundation URL [Accessed: 25.09.2012]SODIS in Senanga, Zambia
This video explains application of Solar Water Disinfection (SODIS) as a simple, cheap and effective method to treat water at the household level by exposing filled bottles to sunlight in Zambia.
EAWAG SODIS in Senanga, Zambia. Keepers Zambia Foundation URL [Accessed: 25.09.2012]Drink Safe Water with SODIS
This poster describes the application of Solar Water Disinfection (SODIS).
KZF (n.y): Drink Safe Water with SODIS. Keepers Zambia Foundation (KZF) URL [Accessed: 20.09.2012]Medical Research SODIS "Solar Water Disinfection"
This video shows Solar Water Disinfection (SODIS) as a solution for providing disinfect drinking water and support one of the world's poorest people with safe and clean water in rural Africa.
NWI (2012): Medical Research SODIS "Solar Water Disinfection". New World International (NWI) URL [Accessed: 25.09.2012]WaterGuard
A poster promoting the point of use water treatment tablet, WaterGuard, as part of the Juba Community Hygiene Improvement Initiative. The actual tablet is the tangible product of a large-scale behaviour change and hygiene improvement strategy.
SISP (2012): WaterGuard. Safe Water for Better Health. Sudan Infrastructure Services Project (SISP) URL [Accessed: 26.09.2012]The Manufacture of Bio-Sand Water Filters in Rural Tanzania
This video shows the manufacture of biosand filters in rural Tanzania.
WATER4LIFE WATER4LIFE (2012): The Manufacture of Bio-Sand Water Filters in Rural Tanzania. URL [Accessed: 25.09.2012]Nyakongo Biosand Filters
This poster summarises an initiative that was conceived to stimulate and support development of social enterprises among students and recent graduates by empowering them with necessary resources, technical skills, and networks to provide sustainable solutions to poverty-related issues in Africa. Its flagship water and sanitation project in Kenya is aimed at providing simple, sustainable access to safe drinking water and basic sanitation.
WSCSD (n.y): Nyakongo Biosand Filters. World Student Community for Sustainable Development (WSCSD) URL [Accessed: 25.09.2012]www.psi.org
Animated Safe Water flyer.