Filtration System for Harvested Water in Sub Saharan Africa Against Water Nexus

Deadline for applications: 26 January 2024

About the Project

In Ethiopia only 38% had access to basic water and 13% had access to safely managed water sanitation services in 2020 according to WHO and UNICEF. In Zambia, 68% had access to basic water and 45% had access to safely managed water in 2022 according to the same source.

The main investigations in the project cover the improvement of water availability for domestic use through implementation of green infrastructures such as revitalization of natural hydrological processes and water harvesting, water treatment with biological measures and filtering, pollutants and waste management and reuse.

The project aims to improve understanding of how Nature based Solutions can be scaled and customized to address the availability of water and consequently food in Ethiopia and Sub-Saharan Africa, using Zambia as case study. Thus it will be focused on one of Zambia’s largest wetland areas called Lukanga Swamp (crucial to the ecosystem of Zambia and the region) located in central Zambia.

Lukanga Swamp serves as a recharge zone for one of the major rivers, the Kafue River, which flows into the Zambezi River. Kafue River supports agricultural activities and the livelihood of local communities, and additionally is the source of water for the capital city (Lusaka) and surrounding areas. This wetland is home to many varieties of animals, reptiles, fish and birds, among them endangered species. Studies have shown that 6 million people (30% of the country population) directly rely on this wetland. Fishing in the wetlands is one of the major economic activities for the local communities. In the rainy season when surrounding areas are flooded, the Lukanga swamps absorb excess water, while in the dry season when areas record droughts, the wetlands serve as sources of water, income and food.  

The community in the Lukanga swamps and surrounding areas use surface water for both potable and non-potable use. The surface water is contaminated due to bacteria and germs resulting from inadequate sanitary facilities, as well as water pollution from heavy metals associated with mining activities. Agricultural activities also lead to contamination of water from phosphate and nitrate fertilisers as well as traces of pesticides. All these can have negative effects on human health and the environment. Despite having an abundant supply of water for most of the year, communities in the Lukanga wetland do not have access to clean water in the dry season (May to October).

During the rainy season (November to April), the area usually receives plentiful rainfall. Unfortunately, the rainwater just goes to waste. Rural communities have no effective means of harnessing rainwater, although there are some reservoirs for animal use, some for irrigation purposes, and a few for human consumption. Fish in the wetland are slowly being depleted, so having small-scale dams for aqua-culture purposes (fish farming) will enhance food security for the community.

The project will investigate sustainable solutions with a focus on rainwater harnessing and water purification using natural materials. The removal of pollutants such as heavy metals (i.e. Cd, Cr, Cu and Pb), organics such as Naftalen or even drugs such as Ibuprofen, can be successfully achieved using the absorptive and at the same time antiseptic properties of activated carbon, which has a well-developed hierarchical open pore structure in the foam, combined with the absorptive and antibacterial properties of Vermiculite.

Water storage and filtration on larger scales requires sensor development and installation for the monitoring of parameters such as Ph, Oxygen levels, etc. Working closely with Zambian Non-Governmental Organization partner partners, the Worldwide Fund for Nature Zambia (WWF), Ethiopian hydrologists, and urban engineers and social scientists from Mekelle University, the student will evaluate the effectiveness of these interventions.