Kampala — FOR weeks, Kwame Ejalu, a resident of Luzira, has not enjoyed fresh air in his villa. "In the evenings the stench is like faeces," he says.

Whenever he wants fresh air, Kwame has to go to other suburbs and then return late only to sleep. "Somehow when you go to bed the nose gets used to the smell," he says.

Like Kwame, more than 1,000 people who live or work around Luzira area have suffered from this stench over the past five weeks. The stench comes from Lake Victoria, as a result of massive algae growth in the Murchison Bay. "It has denied residents fresh air, but no one has explained or cleaned up the mess," says Joseph Senyange, a representative of the beach management unit at Luzira.

On a 10km boat ride from Ggaba to Port Bell last week, Saturday Vision saw a vast mass of green algae. In a one kilometre radius from the point where the Nakivubo Channel enters Lake Victoria, the water has turned black underneath the green algae mass. For another three kilometres beyond the black zone, the water is green and slimmy like paint. An offensive smell emerged from the water, especially the black zone, inconveniencing residents and workers around Luzira.

Fishermen said whereas in the past such green masses lasted only days, this time it had persisted for weeks. The black water closer to the mouth of the Nakivubo Channel has become a permanent feature. "This place is now permanently smelly," says Hussein Tamale, a fisherman at Ggaba landing site on Lake Victoria.

Some fishermen say the green mass has denied them fishing areas as they cannot fish in the smelly water. "I can't imagine eating smelly fish," says Hussein Tamale, a fisherman at Ggaba.

Others say it exposes them to health risks since many of them depend on raw water from the lake for cooking, drinking and other domestic uses.

Fishermen say the water in this area heats up by itself, and produces bubbles. Water Engineer Kiwanuka Ssonko says this could be a result of heat and methane gas produced during the decomposition of organic wastes that flow into the lake through the Nakivubo Channel.

The source of trouble

The locals refer to the green mass as Mubiru, because they associate it with spirits. However, experts blame it on pollution by waste being driven from Kampala through Nakivubo Channel and industries near Port Bell. "The problem is municipal waste and sewerage that flows untreated into the Nakivubo Channel and then into the lake," says Ssonko.

Naturally, algae grow in the lake in small quantities and is food for fish. Organic wastes act as manure, which helps the algae to overgrow. When there is too much algae, it consumes a lot of oxygen, which then causes fish to suffocate.

In addition, the Nakivubo Channel was designed to rush waste water into the lake instead of allowing it to settle in the swamp and be filtered naturally. "It was created by lousy engineering and misplaced priorities," says Dr. Aryamanya Mugisha, the head of the National Environment Management Authority (NEMA).

Mugisha says the channel should be re-designed. The last few kilometres of the channel should be split like the fingers of the human palm so that the waste water spreads into the swamp to encourage natural filtration, a process referred to as reticulation. This solution has been discussed for over nine years but has not been implemented because of bureaucracy and lack of funding.

Natural filter disabled

The Nakivubo wetland, which used to filter the waste, has been heavily encroached and destroyed by human beings through construction and farming, especially during the last 10 years. "The crops and wetland grasses that have replaces papyrus do not have the ability to clean the waste," says Ssonko. "Water used to settle in the swamp for over a week before going into Lake Victoria, but these days soon after a storm you can see dirty water flowing into the lake."

According to the NEMA, Nakivubo wetland has reduced from 6.5 to less than three square kilometres during the last 17 years.

As one of the ways to restore this vital wetland, NEMA plans to start evicting encroachers next week. "It would be useless to redesign the channel without saving the wetland that will filter the waste water," says Dr. Gerald Sawula Musoke, the deputy head of NEMA. "There is a small part of the wetland that is left and it is important to minimise destruction and restore the degraded part".

This destruction of the Nakivubo wetland comes at a time when there is increased pollution from industries that do not have proper waste treatment facilities. Recently, NEMA mounted an inspection of agro-based industries in Luzira, and found Ngege Fish Factory as one of the main polluters. "We found no waste treatment plant," says Dr. Festus Bagoora, an expert from NEMA.

William Olupot of the Wildlife Conservation Society says the pollution comes from various industries as well as Kampala's sewerage treatment plant.

Higher water bills expected

Only 5km from the mouth of the Nakivubo channel, is the Ggaba Water Works, the source of municipal water for Kampala and neighbouring districts. Some of the filth that enters Lake Victoria through the Nakivubo Channel, diffuses towards Ggaba Water Works. Kiwanuka Sonko, an engineer with the National Water and Sewerage Corporation (NWSC), says because of this, more chemicals have to be used to make the water safe for the consumers. "The inputs presently are five times what used to be applied in the 1990s," he says. "The cost of the chemical is still going up".

Sonko says as a result of increasing water treatment costs, NWSC has adopted desperate cost-cutting measures such as reducing staff size, to avoid passing on extra costs to the consumer. But, he warns, soon they might run out of cost-cutting options and resort to increasing water bills to cater for the increasing costs of treatment.

Another measure NWSC is exploring is to treat the waste water within the Nakivubo Channel before it enters Lake Victoria. "This has become like an open sewer and it is useless to pretend that it is a channel for water," says Sonko. "It also gets untreated waste from many sources."

With less than 10% of Kampala's population connected to public sewer systems and the widespread culture of throwing away rubbish, the intervention to treat the waste is timely to save the lake from further pollution.