Wetland destruction behind Lake Victoria surge — experts
Apr 16, 2024
When there is too much rain, water runs towards lakes and available drainage channels. The speed at which the water runs is so high that without controls like swamps and wetlands, it can easily increase water levels in water bodies.
Part of the road which has been reclaimed by Lake Victoria waters in Kalangala. (File Photo)
Prossy Nandudu
Journalist @New Vision
__________________ Transporters on their way to Kaazi-Malanga waiting for a boat to ferry their motorcycles across
Experts in water resources management have warned that continued clearance of wetlands and swamps for settlement and industrialisation, among other commercial activities, will fuel rising water levels on Lake Victoria.
The rise in water levels will not only be realised on Lake Victoria, but also in other water bodies, such as lakes Kyoga and Edward downstream. For the two lakes, Kyoga and Edward, known mainly for fish, fisheries activities will come to a standstill.
The warning was issued by Dr Callist Tindimugaya, a water resources management specialist working with the water ministry.
When there is too much rain, water runs towards lakes and available drainage channels. The speed at which the water runs is so high that without controls like swamps and wetlands, it can easily increase water levels in water bodies.
Unfortunately, most of the swamps around Lake Victoria have been degraded, explained Tindimugaya. He added that wetlands or swamps trap running water whenever there is a lot of rain, hence controlling the speed, and then gradually releasing it into water bodies.
Tindimugaya noted that the natural process minimises the sudden rise in water volumes.
Why the rise in water levels?
Tindimugaya explained that a rise in water levels comes in two ways, one, as heavy rains like those being experienced today and the other due to running water towards water bodies whenever there are heavy rains, since there are no controls in the form of swamps.
The heavy rains experienced today are due to the settlement and cooling off of winds from the Indian Ocean that were meant to release rains in March but were instead diverted, leading to a delay in the onset.
The winds finally cooling off is the reason Uganda is experiencing more than expected amounts of rain, leading to the increase in water levels on Lake Victoria.
Because the country is experiencing an increase in rainfall, which sometimes is short and intense, and sometimes over a longer period, these tend to be more destructive. “For example, you can have the same rainfall. If it starts raining from say 8:00 am and it ends at 10:00 am, you will have rainfall falling for two hours. But if it rains for only 30 minutes, it is the same amount of rainfall. So, due to climate change, we are seeing more intense rainfall falling in a very short period and that causes problems,” he explained.
Tindimugaya added that whenever it rains for a short time, Kampala floods and this has been made worse by the design of the drainage channels, which were not meant to hold large amounts of water.
If the drainage channels are filled with rubbish, too much silt, and no wetlands or swamps to trap the water and release it gradually, as well as no hills or forests, the situation worsens.
“So, the problem is too much rain falling within a short period and the general environmental degradation,” Tindimugaya added.
What determines the increase in water levels on the lake?
Tindimugaya said increased water levels on the lake are determined by the rains falling directly on the lake and then water coming from neighbouring countries like Kenya, Tanzania, Rwanda, and Burundi.
From Rwanda and Burundi, Lake Victoria gets this water through River Kagera. From Kenya, the waters come through the Nzoia and Malaba rivers.
And because those countries have also degraded the environment, more water tends to run to the lake, especially now that the whole region is experiencing the same rain.
How the rise in water levels can be controlled
Tindimugaya said because Lake Victoria is like a basin, it has only two ways through which water is released.
One is through the natural process of evaporation and the artificial process is the controlled release of water through the Nalubaale and Kiira Dams in Jinja.
If left uncontrolled, there will be a lot of pressure exerted on the dams, which can easily break, he warned.
Govt interventions
To manage the water levels, the Government, through the water ministry, recently directed dam operators to release 2,400 cubic metres of water per second to control the rising levels.
Tindimugaya said over the last month, they have been releasing 2,200 cubic metres of water per second, but because the levels have increased, dam operators have been directed to release 2,400 cubic metres per second, starting this Thursday.
“Once they release that amount, then the level will go down. The water is being released to create space for more water coming in due to the ongoing rains.
If we do not do that, then we will reach a point where water is released in Kampala, destroying bridges, and houses and, in a short time, the whole of Kampala, will be flooding.
Immediate solutions
In the meantime, Tindimugaya said restoration of wetlands continues, although most swamps are cleared at night. He added that the government has beefed up enforcement by increasing the number of environment police and recruiting staff to monitor wetlands.
Other impacts of current rains according to UNMA
According to the April 2024 rainfall outlook, more than normal rains will be experienced across the country and these will be characterised by thunderstorms and lightning, as well as flooding in most parts of the country.
To guide the public on how best to benefit from the forecast, the following sectors have been given tips to survive.
In the agricultural sector, farmers have been asked to continue planting and weeding their crops to reduce the rampant growth of weeds, such as nut grass, spear grass, wandering jew, and coach grass, which increase the cost of production.
Waterways, trenches, stone bands, contour trenches diversion channels, and grass bands should be put in place to minimise soil erosion and waterlogging
In pastoral areas, pasture conservation should be considered because there will be rapid growth of foliage and pasture for livestock.
Populations that depend on firewood should consider other energy sources as the forests will all be wet.
Those with Kraals should relocate to raised areas to prevent foot rot diseases due to water stagnating in most kraals whenever it rains.
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