Ggaba suffocating Lake Victoria

Until June 5, World Environment Day, in a campaign, Save Lake Victoria, Vision Group media platforms are running investigative articles, programmes and commentaries highlighting the irresponsible human activities threatening the world’s second largest fresh water lake. Today we explore how the community around Ggaba landing site is polluting the lake.

By Watuwa Timbiti & Agnes Nantabi

Ggaba community and landing site are some of the point sources of pollution which is increasingly eating up the Inner Murchsion Bay. This is where the Ggaba water plant gets water used in Kampala, according to a statement from National Water and Sewerage Corporation (NWSC).

Although the upper side of Ggaba has formal settlement patterns, the settlements in lower Ggaba trading centre, which house low-income earners, are mostly informal, with near make-shift structures, without adequate access routes and sanitary facilities.

“The disposal of human excreta constitutes one of the most critical aspects of environmental health. Although the project area is fully covered by piped water, the waste water management system mostly comprising traditional pit-latrines and septic tanks is lacking in many aspects,” the statement reads in part.

With such low-income informal settlements comes reliance on pit-latrines for excreta disposal worrying though, majority of the pit-latrines are in poor physical condition.

Worse still, a significant proportion of the households, the statement notes, do not possess or have access to a private latrine. And, the few available are difficult to empty because of physical limitations and lack of accessibility due to unplanned housing.

“Since it is not feasible to develop new pits whenever old ones fill up, some of the pits are unplugged during rainy seasons and the sludge is allowed to flow through open channels into the neighbouring Inner Murchison Bay of Lake Victoria,” the statement notes.

Volumes of waste generated

Apart from poor pit-latrine facilities and limited accessibility, Gaba is equally suffocating the lake due to poor and irresponsible garbage disposal and diminishing vegetation cover.

The waste in most cases ends up in water drainage channels and pit-latrines, thus the resulting runoff and siltation ends up in the lake when it rains.

“The situation is aggravated by the fact that most of the surrounding lake shore has been encroached on by private developers. This has led to the depletion of the wet lands, mainly papyrus lining that would act as a natural filter,” the statement says.

Therefore, poor sanitation and solid waste management within the community, have reduced the lake to a siltation and excreta repository.

Poor sewerage system

Speaking during a feasibility study at Gaba landing site early this month, Christopher Kanyesigye, the manager of water quality control at NWSC blamed the mess on poor planning of the city.

“Many people come to the city without good income to construct decent houses. This has made it difficult to provide utilities such as water and sewerage systems, sanitation, waste water collection and solid waste management systems to them,” he noted.

Kanyesigye’s observation enhances Paddy Twesigye’s, the NWSC senior manager projects, who argues that a modern city should have a fully-established sewerage system and of a wider coverage.

“You cannot give sewerage services to a rich man in a slummy area. How about his poor neighbours? What will they use because, obviously, they cannot afford the sewerage services?” he asks.

An aerial view of Ggaba landing site showing human settlement.The crowded houses have poor sewerage and solid waste disposal system, making most of the waste to end up in the lake. PHOTO/Enock Kakande

Water extraction in the lake

As a result of increased pollution in the inner Murchison Bay and subsequent growth of algae, the cost of water treatment has more than tripled from sh170 per cubic metre in 1992 to sh470 today.

This is worsened by temperature inversion during sunny days when the hot water on top turns to the bottom and that at the bottom, which is cold, moves to the top.

“This upward water movement carries with it sediments which feed the algae, thus the greenish algae-loaded water, which is about three metres deep,” explains Twesigye.

Treating and decolouring such water, he notes, is expensive, thus affecting the quality and quantity of water treated. For instance, comparatively, treating a cubic metre of water at Gaba is much more expensive than at the Jinja water treatment plant.

As an immediate solution, NWSC at a cost of 6.5m euros chose to extract water from an algae-free area of the lake.

“We moved a bulk-water pipe 200 metres into the lake and placed another pipe 16 metres deep with water abstracted at 14 metres down,” Twesigye explains.

Construction measures

To curtail the amount of excreta flushed into the lake, NSWC has designed and is establishing sewage treatment plants to extract human waste from the channels.

“One is already under construction between Bugolobi and Namuwongo at a cost of 50m Euros. The one to be constructed at Kinawataka has already been tendered,” Twesigye says.

“This, however, may not be as effective as expected or required if there is no behaviour change upstream of the channels,” warns Twesigye

“It is important to sensitise people to ensure that all excreta is piped to gazetted places for treatment. The Gaba water works was designed to treat unpolluted water, not to clean excreta out of water,” he observes.

Reconstructing wetland

Reconstructing the wetland between Namuwongo and Bugolobi to its capacity of cleansing waste water could be one of the achievements in pollution control, says Alex Gisagara, the NWSC acting managing director.

This can be done using the same natural plants that were there before, for instance, the reeds and papyrus.

The other measure, he points out, is mapping out boundaries on the lower side of the channels. Gisagara says KCCA should ensure supervised and guided construction so that runoff rain is properly controlled to the drainages.

This, he says, requires massive investment upstream of the drainage areas, for instance, in Kololo and Nakawa, so that people can behave responsibly when it comes to solid waste management.