News and Views on Africa from Africa
Last update: 1 July 2022 h. 10:44
Subscribe to our RSS feed
RSS logo

Latest news


Lake Victoria chokes under the water hyacinth

The heavy pollution of Lake Victoria has provided a conducive environment for the spread of numerous weeds such as the deadly water hyacinth, which continues to threaten the lives of the lake basin community.
Zachary Ochieng

Lake Victoria, the second largest fresh water lake in the world after Lake Superior of the US, is facing a serious threat, thanks to the water hyacinth, a deadly weed that has wreaked havoc to urban water supply systems, marine transport and fishing activities. While there are other threats to the lake such as overfishing and pollution of the lake waters, the hyacinth has so far been the strangest phenomenon. The weed has from the early nineties blocked fish landing sites and communal water points along the lakeshore.

The weed, scientifically known as Eichoirnia Crassippes , is found in lakes, swamps, dams and riverine wetland throughout the main drainage systems of Africa. Scientists, however, believe that the water hyacinth originated from the Amazon basin. It is believed to have been brought to East Africa as a pot plant that later found its way into the lake waters. Its rapid proliferation has been blamed on the emission of untreated industrial effluents into the lake.

The proliferation of the hyacinth is directly attributed to the enrichment of the water environment by the effluent from the expanding population around the lake , says Dr Margaret Oduk, a research scientist at the United Nations Environment Programme (UNEP). Dr Oduk adds that the continued infestation of the weed could result in food insecurity as it blocked access to fishing ground.

The green plant produces beautiful purple flowers and has long fibrous roots. The spongy tissues in its stem enable it to float in water. It grows in clusters that form floating mats in the lake and thrives best in polluted waters. According to scientists, the weed spreads out at an alarming rate, doubling its biomass every 15 days.

Mr Obiero Onganga, the Executive Director of OSIENALA (Friends of Lake Victoria) a local environmental NGO based in the lakeside city of Kisumu the weed is an environmental and ecological disaster that has devastated the lake, choking life out of it and threatening it with impunity. According to Onganga, the declining fish stock has had a direct bearing on the declining biodiversity.

Says he: The hyacinth has been spreading very fast over the lake and interfering with light penetration, dissolved oxygen, fish breeding sites, landing beaches and ecology .

Unfortunately, a plan to save the lake shared by the three East African countries of Kenya, Uganda and Tanzania, and funded by the World Bank and the Global Environment Facility (GEF), has made very little impact, especially in Kenya where the first phase is behind schedule by two years. The lake is a shared resource between Kenya (6 per cent), Uganda (45 per cent) and Tanzania (49 per cent).

The rescue plan, mooted in 1994, has been hampered by implementation hurdles, despite elaborate attempts to eliminate the deadly weed. Consequently, the livelihood of the riparian communities who eke out a living from the lake is still threatened.

The project was funded jointly with Uganda and Tanzania in a five year programme at the cost of US$ 70 million, with the World bank providing US$35 million through the International Development Association (IDA) and GEF giving a similar amount. The World Bank document on the Lake Victoria Environmental Management Project (LVEMP) listed water quality monitoring, hyacinth control, fisheries management, research and industrial and municipal waste management as key project objectives.

But five years since the first phase of the project rolled out in 1998, environmentalists admit that Kenya still lags behind Uganda and Tanzania, which have succeeded in controlling the weed and taming pollution and management of waste discharged by municipal authorities in their respective countries. But in Kenya, this has not been the case. Only last month, the Homa Bay Municipal Council invited the ire of environmentalists and the public at large when it discharged raw sewage into the lake. Kenya has already spent US$1.5 million of the project money with nothing to show for it.

A senior LVEMP official who requested anonymity told Africanews that his predecessors at the project never got their priorities right. He explained that instead of the leaders implementing the core projects, they started with some less important ones.

Procurement was bogged down in bureaucracy and mystery. The process was too long, revolving around treasury, the Environment ministry and the Central Bank of Kenya , he said. The official cites the water control laboratory meant to check on pollution at the Kisumu provincial water offices as a casualty of bureaucracy, stalling for several years with 75 per cent of the work already done.

A monitoring and evaluation team from Washington also expressed dissatisfaction over the progress in the fight to eradicate the weed . But as the weed continues to wreak havoc in the lake, opinions are sharply divided over what method should be used to eliminate the hyacinth hassle. Planning and Development minister Prof. Anyan g Nyon go argues that the lake is only 80 metres deep and chopping and dumping the weed into the water body would be disastrous.

Other conservationists argue that the weed can be controlled by mechanical means manpower and machines, but this has mostly been unsuccessful since the weed grows faster than mechanical clearance can cope with it. Various herbicides are also effective but have significant risks for other wetland biodiversity.

However, both methods have been successfully used in Uganda and Tanzania. The Kenya Agricultural Research Institute (KARI) claims that the more than 200000 weevils it had released into the lake to feed on the weed had succeeded in reducing its spread, but the residents as well as a visit to the lake by Africanews confirm that little has been achieved.

The slow implementation of the project has brought to Kisumu a paradox of scarcity in the midst of plenty. Perennial water shortages continue to dog Kisumu city as all the intake points have been blocked by the weed. Marine and navigational activities at the port of Kisumu are also often blocked and clogged by the weed, making it impossible for light steamers to dock.

Marine experts say that the weed would hamper rescue operations in the lake in the event of a disaster.

Contact the editor by clicking here Editor