Purification of Water at a Household Level in Zambia

Requirements and Functional Analysis

The requirement for the project is to design water purification device at a low cost using locally available materials. The purification device is to be used by refugees in Mayukwayukwa in Zambia to filter water to safe drinking standards (Engineers Without Borders, 2016). The functional analysis consists of a three level supply system. On the first level, water is to be obtained from its source such as boreholes and made safe for consumption. This can be done by using a purification device. Once the water is made safe, it is then distributed to water users. The second level of the water supply process stored untreated water is treated and then stored for future use such as during dry periods. The third level of the water supply involves the process used to ensure that water is made safe for consumption. The first step is to remove large particulate such as sand-sized particles in water. Once this is done, the next step involves removing small particulate matter. This is then followed by removing unwanted minerals and chemicals in the water. Finally, pathogens are removed for example treatment of water with chlorine.

Basic Requirements by the EWB

Engineers Without Borders Australia (EWB) in partnership with the United Nations High Commissioner for Refugees has developed a challenge where participants are required to design a water purification device. Zambia decided to integrate refugees from Rwanda and Angola (Engineers without Borders, 2016). This has led to the need to develop engineering and technical solutions to assist the refugees to create sustainable livelihoods as they integrate into the society in Zambia. The solutions will also help current refugees and the local communities in improving their ways of life. The EWB Challenge requires participants to design a low-cost water purification device that the refugees and local communities can use in their homes to make water safe for consumption. Currently, the source of water for the refugees has been boreholes and wells. They are encouraged to boil the water to make it safe. The aim of the challenge is to identify an alternative water purification method that can easily be used by the communities.

Refinement of the Scope of the Problem

Water is important in sustaining life. This means that a satisfactory supply of water must be availed to all people. The provision of a satisfactory supply of water means that such water must be adequate, safe and easily accessible (World Health Organization, 2006). Access to safe drinking water means ensuring that people access water that does not pose any significant risk to health when used for a long time. The water purification device to be designed must, therefore, be capable of removing hazardous constituents of water. Currently, the refugees boil water to make it safe for drinking. However, this is not always the case as many of them do not boil water from boreholes as it is considered naturally filtered. The water purification device should be capable of achieving the same results as boiling water so as to be considered a better alternative for the refugees.

Breakdown of the Problem

The process of making water safe for consumption means removing all particulate matter, unwanted minerals, and chemicals as well as removing pathogens (World Health Organization, 2005). The design of the filter should be such that it is capable of filtering the water to safe drinking standards. Although many countries may differ on what amounts to safe drinking water standards, there are categories of water characteristics or constituents that affect the quality of water. These elements are physical, microbial, chemical and radiological elements (National Health and Medical Research Council, 2011). The filter to be designed must be capable of removing these elements to make water safe for drinking. The physical elements refer to the colour, taste, and odour of water. The filter must be able to remove suspended particles in the water and leave the true colour of the water. Microbial elements refer to the contamination of water with human or animal waste (Hallmark, 2011). Chemical elements in water include pesticides, chlorides, dissolved salts among others. These elements are capable of causing health problems where there is prolonged exposure. The filter must also eliminate the radionuclides that may be in water which results from accidental releases of radioactive substances to the environment (Fraunhofer Institute for Interfacial Engineering and Biotechnology, 2016). The design of the filter must be such that these harmful elements are removed making water safe for consumption.


Engineers Without Borders (2016). UNHCR Zambia. Retrieved November 9, 2016, from: http://www.ewbchallenge.org/unhcr-zambia

Fraunhofer Institute for Interfacial Engineering and Biotechnology (2016). Treatment and purification of process (waste) water resource and energy efficient. Retrieved November 9, 2016, from: http://www.igb.fraunhofer.de/content/dam/igb/en/documents/brochures/_uber/1506-BR_%C3%BCber-prozesswasseraufbereitung-en.pdf

Hallmark, B. (2011). Sustainable development: Water purification technology in Zambia. Kungsholmens Gymnasium.

National Health and Medical Research Council (2011). Australian drinking water guidelines 6. Australian Government.

World Health Organization (2005). Water treatment. World Health Organization, Geneva.

World Health Organization (2006). Guidelines for drinking-water quality. World Health Organization, Geneva.