The persistent foul smell reported along sections of Lake Victoria has been attributed to intensified algal blooms caused by rising pollution levels, according to information released by the Ministry of Water and Environment.
The ministry said Lake Victoria and its basin support more than 45 million people as a source of drinking water, transport, hydropower, fisheries and trade, but the lake is increasingly under pressure from pollution originating within its catchment.
The Inner Murchison Bay, one of the most heavily utilised sections of the lake in Uganda, has been identified as the most affected area due to its shallow depth of less than 10 metres and its sheltered nature. Other bays experiencing similar challenges include Kitubulu and Nakiwogo in Entebbe, and Napoleon Gulf in Jinja.
According to the ministry, these bays receive heavy pollution loads from surface runoff laden with silt, human and plastic waste, municipal wastewater from surrounding suburbs, industrial effluent and agricultural runoff. The situation has been aggravated by degradation of wetlands around the lake, which previously acted as natural filters for nutrients and organic matter.
The ministry operates a water quality monitoring network comprising 23 stations in Inner Murchison Bay and 10 stations in Entebbe Bay. Data collected quarterly shows a persistent rise in nutrient concentrations, particularly nitrogen and phosphorus, which are key drivers of excessive algal growth.
Government said prolonged dry conditions and high temperatures experienced over the past month triggered mixing in the bays, accelerating algal blooms. When the algae die and decompose, they consume oxygen and release gases such as hydrogen sulphide and ammonia, which are responsible for the foul smell being reported, especially around Luzira and parts of Entebbe.
“These conditions lower oxygen levels in the water, posing a serious threat to aquatic life and potentially leading to fish kills,” the ministry said. Decomposing algae also release absorbed nutrients back into the lake, sustaining a cycle of repeated blooms.
To address the problem, the ministry said it is restoring degraded wetlands, prioritising enforcement of the 200-metre lake buffer zone, and strengthening regular water quality monitoring to guide policy and remedial action.
Industries in the lake catchment are being supported to adopt cleaner production techniques that minimise wastewater generation and reduce effluent discharge.
Enforcement of effluent discharge permits for industries and municipal treatment plants has also been scaled up, while community awareness campaigns are being intensified to curb pollution of the lake.
However, the ministry acknowledged that additional efforts are required, including improved solid waste management, promotion of environmentally friendly agricultural practices, stronger enforcement by urban authorities, and expanded public sensitisation to foster collective responsibility for protecting the lake.
The ministry emphasised that restoring and maintaining the ecological balance of Lake Victoria will require coordinated action among government agencies, local authorities, communities and environmental organisations.
“Protecting the environment and saving our valued Lake Victoria requires the contribution of every Ugandan,” the ministry said.
