Villagers cope with changing Zambezi River

Works by Sino Hydro a Chinese Group of company doing construction works on the Zambezi River. Sino Hydro won a contract to build two additional units at Lake Kariba.

By DOREEN NAWA
FOR the last 40 years that Tryson Hamaambo, the Sitinkwe village headman has been living in Sitinkwe, a settlement for people who were displaced during Kariba Dam construction, he has never had to walk a long distance to find a waterlogged area for his off-season cultivation.
But today, the story is different; he walks quite a distance from his village to get an area that will sustain his year-round cultivation.
This is because the Zambezi River has never experienced reduced water levels as it has in the last five years.
“Convincing people living along the Zambezi River that a river they have known their whole lives is not the river it once was or could be is not difficult. This is because these changes are so visible because they have caused serious hardships to the community whose lives are dependent on the Zambezi Basin,” headman Sitinkwe says.
According to headman Sitinkwe, the changes mainly driven by developmental projects along the river basin have affected the soil, water levels and vegetation in the area.
The changes to the river have brought great hardships to the people and wildlife on the Zambezi basin, especially in the lower Zambezi valley of Zambia.
“We have had problems here in terms of water levels; the water flow keeps reducing every year. But normally the water levels only increase when the spillway gates are opened,” says Joseph Milandu, a peasant farmer in Sitinkwe village.

Headman Sitiinkwe

“This is not the Zambezi we knew a decade or two ago. I used to do my gardening very close to my home because I had enough dampness for my vegetables. But now I have to follow the water,” he says.
“And when we have floods, we have them in extreme levels.”
For Mr Milandu, flooding is another challenge, “Besides the changing water levels, the other challenge we have here is flooding. Floods come without warning, destroying our property and shelter.”
For 25 years, erratic and mistimed flooding below the Kariba Dam has adversely affected the living standards of thousands of downstream households and decimated one of the most productive and diverse wetland ecosystems in Africa; the Zambezi Delta.
According to Mr Milandu, the diminishing water levels are mostly due to the numerous construction of dams in the area.
“We never had these problems in the first few years after the construction of Kariba Dam about four decades ago.
But because of the high demand in hydroelectricity, the river has seen numerous construction of dams, therefore giving pressure to the river on the distribution of the water resource between wildlife and human beings,” says Mr Milandu.
There are fishmongers too whose lives revolve around the Zambezi River and any reduction in the water levels affects their livelihoods.

Cephas Mweemba

Cephas Mweenda, a fishmonger, has a similar story about how the diminishing water levels on the Zambezi River have affected his usual business.
“A few years ago, I used to fish a few kilometres away from our community and I could go for four hours only and come back with a satisfying catch. But now the situation is different. I go for the whole night to get a desired catch of fish which is too dangerous for me and my family. I get on the river around 07:00 hours in the night and get out at 06:00 hours the following day. The change has been due to an annual drop in the water levels on the Zambezi River. We only have adequate water flow when the flood gates on the Kariba Dam walls are open,” Mr Mweenda says.
And Elizabeth Karonga, the public relations and communications manager for the Zambezi River Authority (ZRA) acknowledges that the Zambezi River is no longer the same.
“It is true that the river that we knew three decades ago is not the same and this is because of numerous developments that are taking place along the Zambezi River. These developments could be hydro-power projects, tourism projects, human settlements, and just the impact of climate change,” Ms Karonga says.
The Zambezi is also one of the most heavily dammed rivers in Africa, with about 30 large storage reservoirs holding back its flow.
Four of the world’s largest hydroelectric dams are Kariba, the third largest man-made reservoir in the world, Itezhi-Tezhi, Kafue and Cahora Bassa in neighbouring Mozambique. These dams have stopped most of the river’s annual floods with their huge reservoirs.
The Zambezi is one of Africa’s most magnificent rivers. It is a lifeline for many people and provides a unique habitat for numerous significant species.

An aerial view of Lake Kariba on the Zambezi river

To meet human development needs, the river has been heavily modified, as evidenced by the construction of huge dams in the main stem and some of the river tributaries to meet the energy demand of Southern Africa. This turns out to be the challenge that the people living along this water body are facing.
According to a study, A Risky Climate for Southern African Hydro, the future of the Zambezi Basin exemplifies the challenges faced by decision-makers weighing potential benefits of hydropower developments against the risks of hydrological change.
The Zambezi basin is the largest in southern Africa, with a total drainage area of 1.4 kilometre squares. The basin currently has approximately 5, 000 megawatts of installed hydropower generation capacity, including the massive Kariba (whose reservoir is, by volume, the largest in the world) and Cahora Bassa dams. An additional 13, 000 megawatts of hydropower potential has been identified.
Across the continent, African leaders are under pressure to grow their national economies and to raise the standards of living for their people, which translate into increased demands for energy.
And hydropower is the easiest source as it is being promoted as a source of large-scale energy capacity for the continent.
However, southern Africa, home to the Zambezi River is already 60 per cent dependent on hydropower for its power supply, thereby putting the Zambezi River under pressure.
In the study, the Zambezi is expected to experience drier and more prolonged drought periods and there will be a significant reduction in the amount of water flowing through the river system, affecting all eight countries it passes through.

Zambezi River

The water that feeds the river is expected to decrease by between 26 per cent and 40 per cent in another four decades, the study observed.
The study says because large reservoirs evaporate more water than natural rivers, big dams could worsen local water deficits and reduces water for hydropower.
Already, more than 11 per cent of the Zambezi’s mean annual flow is lost to evaporation from large hydropower dams’ reservoirs. These water losses increase the risk of shortfalls in power generation, and significantly impact downstream ecosystem functions.
Two more dams are underway on the Zambezi. The design for two of the larger dam projects proposed for the Zambezi, Batoka Gorge and Mphanda Nkuwa dams, are based on historical hydrological records and have not been evaluated for the risks associated with reduced mean annual flows and more extreme flood and drought cycles. Sithembiso Mhlanga, Zambezi River Authority’s dam safety senior manager confirmed this.
The Zambezi River Basin is home to about 40 million people who rely on the river for drinking water, fisheries, irrigation, hydropower production, mining and industry, ecosystem maintenance, and other uses.