Turning a Threat into an Opportunity: How Water Hyacinth Can Benefit Africa's Environment and Economy

The car’s engine rumbles as your face leans against the cool glass of the window. You stare at the vast, flat expanse of green foliage. A distant memory triggers an alarm in your mind. Hold on… isn’t this a lake? As your vision swims into focus, you realise you’re not looking at a large flat area of grassland, but a shifting, suffocating mass of floating plants – water hyacinth!

This is likely a familiar experience, given the alarming rapidity of water hyacinth’s global spread. This invasive species, originally from South America, is ubiquitous in African waterways. Creating anoxic conditions that threaten local biodiversity, providing a breeding ground for malarial mosquitoes, sheltering poisonous snakes, and clogging boat engines, water hyacinth is a serious environmental issue. Despite the efforts by local communities to curb its growth, the plant continues to thrive because of relentless pollution form manufacturing, agricultural, and wastewater processes.

Creative solutions to control this pest are urgently needed, and Africa is exploring ways to manage – and maybe even benefit from – water hyacinth. Here are some surprising facts about how this plant could be used to our advantage:

1.      Removal of pharmaceutical toxins from water systems

Medications that humans and animals consume are often excreted through waste. These pharmaceutical compounds accumulate in the food chain, causing severe disruption to ecosystems. Professor Lawrence Mzukisi Madikizela at the University of South Africa, in collaboration with the Johannes Kepler University, Austria, discovered traces of pharmaceutical compounds such as tramadol (pain-killer) and lidocaine (anaesthetic) in water hyacinths. This research not only highlights the value of water hyacinth for monitoring contamination, but also the potential of utilising water hyacinth to filter wastewater.

2.      Biogas and biofertilizer

The decomposition of water hyacinth can be harnessed to create biogas, a more environmentally friendly energy source than fossil fuels. Biogas offers an innovative solution to Africa’s fuel shortages and can be used for heating, cooking, and lighting, particularly in resource-limited communities. The byproducts of the decomposition process can be turned into biofertilizer, which can then be sold to the agricultural sector. However, caution must be exercised to avoid compromising food sources with pharmaceutical waste by using contaminated biofertilizer.

3.     Prevention of overfishing

Water hyacinth clogs waterways, hindering fishing activities. In partnership with the University of Gothenburg, Eseza Kateregga from Makerere University in Uganda studied the effects of water hyacinth on fish populations in Lake Victoria. The researchers found that fish catchability was significantly reduced due to the presence of water hyacinth, allowing pressured fish populations to recover and promoting greater fish biodiversity in the lake.

4.     Removal of heavy metals from water sources

In addition to pharmaceutical compounds, water hyacinth can also remove heavy metals such as lead and mercury from water, making it safer for both human and animal consumption.

5.     Textiles and building materials

Women in Kenya are converting water hyacinth fibres into eco-friendly household products such as bins, chairs, and handbags. Meanwhile, Samrawit Tewelde, in pursuit of his Master’s in Mechanical Engineering at the University of Addis Ababa, explored the feasibility of using water hyacinth as a building material.

The challenges that face Africa in terms of pollution, energy, and food insecurity are daunting. Yet these challenges present an opportunity to find creative solutions that can improve lives. While water hyacinth poses a serious threat to biodiversity and healthy ecosystems, it can be managed through innovative strategies that span multiple areas of expertise. Africa is working hard to address these issues, and I look forward to seeing these solutions implemented with hope and optimism.

Further reading:

• Ilo, O.P., Simatele, M.D., Nkomo, S.p.L., Mkhize, N.M., and Prabhu, N.G. (2020). The benefits of water hyacinth (Eichhornia crassipes) for Southern Africa: A review. Sustainability 12, 9222.

• Himmelsbach, M., Mlynek, F., Buchberger, W., Madikizela, L., and Klampfl, C.W. (2024). Analyzing water hyacinth plants from two South African rivers for the detection of seven pharmaceuticals and their metabolites. Electrophoresis.

• Tewelde, S.A., Lemu, H.G., and Dawit, J.B. (2022). Mechanical property characterization of water hyacinth and glass fiber reinforced hybrid composite. Materials Today: Proceedings 62, 6445-6449.

• Güereña, D., Neufeldt, H., Berazneva, J., and Duby, S. (2015). Water hyacinth control in Lake Victoria: Transforming an ecological catastrophe into economic, social, and environmental benefits. Sustainable Production and Consumption 3, 59-69.

• Kateregga, E., and Sterner, T. (2009). Lake Victoria fish stocks and the effects of water hyacinth. The Journal of Environment & Development 18, 62-78.

• Madikizela, L.M. (2021). Removal of organic pollutants in water using water hyacinth (Eichhornia crassipes). Journal of environmental management 295, 113153.

• Oketch, A. (2013). Women group makes cash weaving laptop bags from hyacinth. https://nation.africa/lifestyle/money/Women-group-makes-cash-weaving-laptop-bags-from-hyacinth/435440-2062452-4hdkee/index.html.