The Kariba Dam regulates the flow of water into the Zambezi River, which straddles the border between the two countries, from Lake Kariba, which is formed by the dam. But because of a lack of rainfall and low inflow from the upstream portion of the river and its tributaries, Lake Kariba’s water level fell below 1 percent of capacity on Dec. 28, compared with 20 percent one year earlier, according to data from the Zambezi River Authority.
The dam generally produces 1,080 megawatts of electricity output for Zambia and 1,050 megawatts to Zimbabwe. Now, both countries are limited to less than 400 megawatts.
Zambia’s leading power company, ZESCO, which supplies energy to over 80 percent of the country, said early Wednesday that it would immediately increase the length of power cuts from six hours to 12 hours.
In a statement, ZESCO said that, as of Dec. 31, the water level was at 475.60 meters above sea level, “a situation that has necessitated the reduction of generation.” It added that the reduction, to below 400 megawatts, affected “the ability to meet the system load/customer power demand, especially during morning and evening peak demand periods.”
Because of the insufficient levels, Zimbabweans have been forced to endure 19 hours of power outages a day.
The shortage is bringing challenges for small businesses and households that can’t afford alternative electricity supplies and rely on hydroelectric power for their daily activities.
“Everyone in Zambia now is nervous about the shortage of electricity due to the load shedding being implemented currently by ZESCO,” Archie Mulunda, a civil rights activist based in Kitwe, Zambia, told The Washington Post.
He worries that power outages will cause food to spoil in supermarkets and that other small businesses will be “seriously affected.” He fears that the outages will make it nearly impossible to use his desktop computer, affecting his ability to work from home.
Mulunda, 40, is also nervous about what the extended power outages will mean for his wife and three children, who will be home until the middle of January because of school break.
“We [will] need to find other means of energy to prepare some warm foodstuff for my children. We really need enough energy for the family use,” Mulunda said. “We are more worried about food storage in our homes. Definitely, a lot of people’s foodstuff will go bad due to long hours of load shedding.”
Bloomberg News reported the low water levels have seriously harmed the local fishing industry.
Harry Verhoeven, a senior research scholar at Columbia’s Center on Global Energy Policy, wrote that the power cuts have already “crippled” Zimbabwe’s basic industrial and agricultural activities.
“[T]he drying up of the Kariba reservoir has devastating consequences not only for electricity generation and regional water security, but also because it undercuts traditional strategies in Zambia and Zimbabwe for adapting to climate variability,” Verhoeven wrote.
The dam, which is 420 feet tall and 1,900 feet across and built in the 1950s, may get a boost if the rainy season — which typically extends into March — delivers. However, rains have proved unreliable in recent years.
A 2021 study in the Frontiers in Climate journal noted temperatures in Zimbabwe have risen about 1 degree Celsius over the last 40 years, while drought frequency has increased from once per decade to once every three years, and that human-caused climate change has intensified these trends.
Jason Samenow contributed to this report.