World’s largest artificial lake drops by six metres in three years after lengthy drought

This article is more than 6 months old

This article is more than 6 months old

Zambia is facing severe water and electricity shortages after a lengthy drought, with reservoir levels remaining worryingly low despite recent rains.

Water levels in Lake Kariba, the world’s largest artificial lake at more than 5,500 sq km, have dropped by six metres in the past three years.

In early March, available water for hydroelectric production at the Kariba dam, which spans the border between Zambia and Zimbabwe, was about 11.5%, a slight recovery on the record low in January.

A year earlier, hydro levels at the lake exceeded 42%. When running at capacity, the hydroelectric plant produces more than 2.1GW of electricity.

“People see the recent rainfall and the flooding and wonder why the lake isn’t filling up, but what you have to understand is just how huge it is, and how much water has been lost”, said Patrick Siptela, a design engineer with the Zambezi River Authority.

It is now restricted to about a quarter of capacity, leading to frequent power outages across both countries, with many businesses relying on diesel generators for eight hours a day.

About half of Zambia’s total electrical power comes from the Kariba dam, Siptela said. However, this key source of low-carbon power is susceptible to climate-driven impacts in the region. Records dating to 1960 show a warming trend of 0.34C per decade. This suggests the country has warmed by at least 1.7C in 60 years.

In tandem with this strong warming trend, average rainfall in Zambia has fallen by 2.3% per decade in the same period.

The nature and timing of rainfall is also changing. After months of severe drought, recent torrential downpours have destroyed crops and infrastructure.

“Some of our roads that have stood the test of time for years are now succumbing. We know the conditions are really extreme”, said Carol Mwape Zulu, the chief climate change officer at Zambia’s Ministry of Lands and Natural Resources.

She said climate change could “draw development backwards. It’s not just immediate infrastructure damage – you realise it has an impact on education, on children who can’t access schools. It also impacts health issues, nutrition, food security – and malnutrition is holding back children’s development.”

Facebook Twitter Pinterest Average rainfall in Zambia has fallen by 2.3% per decade since 1960. Photograph: Guillem Sartorio/AFP via Getty Images

Zambia was also experiencing rapid deforestation of 276,000 hectares a year, Mwape Zulu said. Many traders sell baskets of charcoal on the roadside, much of it sourced from larger hardwood trees. In urban areas, charcoal is used for cooking because it is cheaper and more reliable than grid electricity.

Some farmers whose crops and livestock have been hard hit by droughts are turning to charcoal production. “We don’t like to cut the trees but we have no choice,” said Diana Moono, a charcoal seller who has five children. “The drought has taken most of our crops, so we have to find some money somehow.”

Alexander Kasenzi, the director of the NGO Harvest Help Zambia said the death of wild animals in Gwembe valley during the recent droughts was unprecedented. “Local people cannot recall a period when even the wildlife was affected,” he said.

Cattle herders abandoned their livestock in the bush and many cows and goats have died from the water shortage. Local women have to queue from 1am each day to access what limited water is available from boreholes.

“I have a strong feeling that what we’re experiencing now has come to stay, and we have to completely change our thinking if we’re to survive. It’s getting tougher and tougher,” Kasenzi said.

In a remote rural part of Siavonga district, Lanson Hannidra, an 80-year-old farmer, recalls a comparable period of severe drought in the 1950s. “When that happened, we used to go looking for food and beg from our less affected neighbours – but this time, they too have nothing.”