Human activity chocking Uganda's wetlands

trueLake Victoria is under threat, and the very people this natural resource is supposed to serve are the ones threatening its existence. Until World Environment Day, June 5, in a campaign, Save Lake Victoria, Vision Group media platforms will run investigative articles and commentaries highlighting the irresponsible human activities threatening the world’s second largest fresh water lake.

By Watuwa Timbiti

Kampala hills have, over the years, presented panoramic eye-hugging sights, comprising splendid houses and sprawling residences. Down from the hills, almost every available piece of land is a construction site.

The situation in the city centre is a tenser sight — it is a bastion of huge construction works, almost every other road or corner has an iron-sheet fenced plot inside which is a multi-billion storeyed structure under construction.

On the other hand, finished or quarter-finished shopping malls and arcades, with traders getting in their merchandise to start business, are a common sight in Kampala and other towns.

Although the changing face of Uganda’s construction sector is a positive development expected to improved living and housing standards, the sector’s dependence on natural resources such as extraction of clay in wetlands for brick making, hard core mining and sand mining does not augur well for the future.

The extraction has, for instance, disfigured the overall topography and altered the biodiversity and ecosystem of many areas.

This is not only a dangerous trend to the environment, but has affected the large water bodies such as Lake Victoria, the streams that feed into these water bodies and the surrounding wetlands from which all Ugandans derive a livelihood.

Wetlands are ­ filters

The environmental effects of commercial brick-making are, for instance, visible in the Kawanda wetland in Wakiso district on the Kampala- Luwero road.

The wetland has been reduced to huge gaping holes filled with dirty stagnant water.

Prof. Majaliwa Mwanjalolo of the department of geography, geo-informatics and climate sciences at Makerere University explains that wetlands act as filters of pollutants and holding places of runoff water and silt.

He warns that destroying and altering such natural resources spurs pollution, fl ooding and siltation of larger water bodies such as Lake Victoria, which receives most of the water from other wetlands.

Similarly, Victor Egwal, a post-graduate student of environmental and natural sciences at Makerere University, notes that brickmaking is a threat to the country’s wetlands.

“The activity affects the environment through clay extraction, dust from material handling and processing as well as gas emissions from fuel combustion,” he says.

Brick burning due to the increased demand of building materials, he explains, results in gas emissions from fuel combustion.

The demand for bricks has resulted into the demand for wood energy to burn the bricks causing massive deforestation, reducing the amount of rainfall and lowering the water levels in Lake Victoria.

Apart from carbon emissions, brick-burning, over the years, destroys the fertility of wetlands and affects the vegetation cover.

The holes that are dug in the process of extracting clay, Egwal notes, lower the water table of the area, drying up the uplands around the affected areas, which causes a significant reduction of water in wetlands and affects the water levels of the lake.

“The stagnant water in the resultant ponds provides a breeding ground for mosquitoes that cause malaria to people in such places,” Egwal warns.

He observes that the activity equally displaces animals and plants in these areas and disturbs the entire ecosystem.

true
Water-filled pits like these are a common sight in a wetland at Kawanda on Bombo Road, where clay for making bricks is dug

Hard core mining

Apart from brick making and other human activities such as settlement and subsistence farming, Egwal says hard core mining, such as the one taking place on the hills near Kigo Prison off Entebbe Road, is a threat to the wetlands and Lake Victoria as it affects the water quality.

“Dust and small stones from stone quarries disturb the flow of minor rivers, streams and canals that feed into the wetlands, resulting causing blockage and alteration of drainage. This leads to soil erosion and floods in the adjacent areas,” he says.

He warns that the silt from the rubbles from broken stones and hard core mining alters the aquatic habitat of fish and other organisms, leading to an imbalance in the ecology in the wetlands and the lake.

For heavy industrial hard core mining, where heavy machinery is used for mining and transportation, Egwal says the machines use fuel and lubricants.

The oil spills from the equipment during repairs and maintenance will seep into the ground near the wetlands and subsequently flow into the lake affecting the terrestrial and aquatic ecosystem.

Egwal notes that in most cases, the heaps of soil dug up during the mining get carried down into the wetlands, resulting in siltation.

And, in areas where wetlands have been destroyed, the soil is directly deposited into the lake, making it shallower and causing difficulty in fish breeding.

Rocks and deadly chemicals

Apart from affecting the wetlands and the lake with siltation, Mwanjalolo warns that hard core mining can be a health risk.

“Some of the mined rocks could even be dangerous to human health depending on the intensity of their chemical content,” he notes.

“They might have chemical elements that are dangerously to human life yet people may not be able to tell which rock is dangerous and which one is not.”

These dangerous chemical elements get washed down into the wetlands and subsequently into the lake, destabilizing fish breeding and the entire aquatic life.

Mwanjalolo cites a case in the D.R. Congo, where a man inadvertently dug up uranium and kept it in the house covered with a saucepan.

However, almost every other day, he realised the rock was reducing in size until a friend, who had paid him a visit told him it was uranium. He had to throw it away immediately.

According to online sources uranium inhalation causes kidney toxicity. Inhalation can be caused by breathing air containing uranium dusts or eating substances containing uranium, which then enters the bloodstream.

Once in the bloodstream, the uranium compounds are filtered by the kidneys, where they can cause damage to the kidney cells. Very high uranium intakes can cause acute kidney failure and death.

Need to re­fill dug up areas

Most of the wetlands and areas where hard core mining has taken place, Mwanjalolo observes, belong to the Government or individuals.

“The brick makers and hard core miners pay money to the land owners to operate on their land. The solution, therefore, would be to identify these land owners and involve them in the process of refilling and replanting the dug up areas,” he suggests.

Dug up areas should be filled during or at the end of the mining process to minimize loss of vegetation cover and the resultant effects such as run-off, soil erosion, siltation and water pollution.

The sites should be restored through construction of burrow pits, landscaping and tree and grass planting where appropriate.