World’s largest man-made Kariba Dam in Zambia is experiencing dangerously low water levels which is bad in a country that over-relies on hydropower to generate electricity.
The water levels at Kariba Dam which is situated at the border of Zambia and Zimbabwe, has dropped with the Zambezi River Authority (ZRA) saying that if it does not rain any time soon, power generation will be suspended.
The drop has been contributed by the over-use by Zambians and Zimbabweans with poor rains worsening the situation. By mid-July last year, the low levels had dropped to 40% and by November the water stood at 21% with less than 1% left for usage.
Last week, the water levels dropped to below 14% prompting the shutdown of the dam’s hydroelectric plants. According to Bloomberg Business the Zambian Energy Minister Dora Siliya said: “The situation is dire,” Siliya told reporters Thursday in Lusaka, Zambia’s capital. “I’m praying. We sit here and gaze at the sky and say, ‘please, the levels of Kariba are at extremely dangerous levels.’”
Now businesses in Zambia are suffering due to the reduced electricity. Mining companies in Zambia, have had to reduce their electricity use and buy expensive imports. Households and businesses have to endure power cuts as long as 14 hours a day. Importing emergency generation could negatively affect government’s 2016 budget.
Normally, Zimbabwe requires up to 2 200 megawatts (MW) of electricity per day. However, the dam is only producing about 895MW inclusive of imports. Although Hwange Thermal Station adds to the national grid, the two produce 95% of power needed thus a collapse of one project results to a major electricity deficit.
It’s not just the water levels, the walls of the dam are wearing out
The status of the dam is not an ‘if’ but a ‘when’ situation.
The history of the gigantic dam dates back to 1950’s when the construction of the walls began. The structure which stands 128 meters tall and 579 meters wide is now on the verge of collapsing after being operational for more than 50 years.
With a thickness of over 24 meters, the walls are swelling due to chemical reactions as the water pass through the floodgates.
Kariba Dam was created to collect waters from the Zambezi floodplains and was among other things a great economic opportunity for locals. But these same waters, if the walls are not repaired could cause havoc to people living along the Zambezi river which extends to neighboring Zimbabwe, and Malawi and Mozambique further downstream. This is not mention the loss of the key source of electricity in Zimbabwe and Zambia.
The Zambezi River rises in north western Zambia and its catchment area covers 1 352 000 square kilometers and eight countries, namely Angola, Botswana, Malawi, Mozambique, Namibia, Tanzania, Zambia and Zimbabwe. It enters the Indian Ocean in Mozambique at Quelimane.
To reach the Indian Ocean, Zambezi river, the fourth largest river to drain into the ocean, flows for 2650 kilometers from Zambia. Kariba Dam is approximately situated halfway down Zambezi river.
A recent 4.6 magnitude earthquake that hit Kariba area and parts of Zambia in January 12, has further aggravated the weakening walls.
In a statement, the director at the Geological Survey Department in Zambia, Chipilaika Mukofu, said that the effects of the earthquake were being investigated to identify possible implications at Kariba Dam.
According to a report by the Institute of Risk Management SA (IRMSA), the state of Kariba Dam is a time bomb which will take a toll on many people within the course of the Zambezi River.
With a gaping crater of eroded bedrock undercutting its foundation, the report titled Impact of the failure of the Kariba Dam noted that the structure was in a dangerous state.
Although the low levels in the dam are taking some pressure off the failing construction, the future of the dam still remains critical and the concerned authorities should devise a long lasting solution before it is too late.
Even as Zambians and Zimbabweans sit and pray for rainfall, government and other stakeholders should strategize on how to renovate the walls to avoid the impending danger associated with the collapse of the walls. Up to 3.5 million people living downstream are said to be under the risk when the walls finally give way.