Kariba Dam rehab completed

PHILLIMON MHLANGA

The Zambezi River Authority (ZRA), a joint venture outfit owned by the governments of Zimbabwe and Zambia, has completed the long-awaited rehabilitation of Kariba Dam’s six floodgates, a milestone that secures the structural integrity of one of Africa’s most strategic hydroelectric assets and brings fresh hope for energy stability in Zimbabwe and Zambia.

ZRA chief executive  Munyaradzi Munodawafa hailed the development as “historic for the region,” underscoring its significance not just for the two countries but for Southern Africa’s wider power grid.

“The successful completion of this final test confirms that all six refurbished sluices are now fully functional,  a critical milestone in strengthening the dam’s integrity and ensuring the long-term safety, resilience, and reliability of this vital regional power source,” Munodawafa said.

“With this final test, the Authority proudly celebrates another historic step forward in securing the Kariba Dam for generations to come.”

The final leakage tests, which released more than 9,000 cubic metres of water, equivalent to 18 seconds of full generation output, confirmed that water losses are now well below international safety thresholds.

The successful outcome concludes a decade-long, US$300m engineering and financing effort that some experts once feared might falter under technical and political pressures.

Commissioned in 1959, Kariba remains the world’s largest man-made reservoir by volume. Stretching along the border between Zimbabwe and Zambia, it has become the backbone of both countries’ power systems and a central pillar of regional energy trade.

On the Zimbabwean side, the Kariba South Hydropower Station contributes more than 1,000MW to the grid, providing over half of the nation’s electricity supply.

In Zambia, the Kariba North Bank Station produces a similar output, covering about one-third of domestic demand.

The combined capacity underpins industries, mines, and households across the region.

Crucially, Kariba’s hydroelectricity is the cheapest source of power available to both nations.

While thermal generation in Zimbabwe costs upwards of 10 US cents per kilowatt-hour, and emergency imports are even higher, Kariba’s hydropower is produced at a fraction of that cost.

For economies grappling with inflation, foreign currency shortages, and investment pressures, the availability of low-cost electricity from Kariba has been indispensable.

Yet this lifeline has faced immense strain.

A few years ago, engineers warned that decades of water discharge had dangerously deepened and narrowed the plunge pool below the dam wall, threatening its foundations.

At the same time, ageing sluice gates were corroding and leaking, raising the risk of catastrophic failure.

Left unaddressed, the vulnerabilities could have crippled energy supply for millions and destabilised two already fragile economies.

The Kariba Dam Rehabilitation Project, launched in 2014, was designed to avert that looming crisis.

It was backed by a consortium of international financiers including the World Bank, the African Development Bank, the European Union, the Swedish International Development Cooperation Agency, and other bilateral donors.

The financing package, exceeding US$300m, reflected not only technical urgency but also the geopolitical necessity of stabilising Southern Africa’s energy lifeline.

The project had three critical components.

The plunge pool reshaping reduced erosion risks and stabilised foundations.

The spillway and floodgate rehabilitation restored safe water regulation.

Institutional strengthening of the ZRA was also prioritised to ensure sound management for the future.

The plunge pool works, completed in 2021, involved advanced excavation techniques to widen and stabilise the pool, reducing turbulence and preserving the dam wall’s integrity.

The floodgate refurbishment — finalised this year, modernised decades-old steelwork, replaced failing mechanisms, and restored the gates to international safety standards.

The completion of the final leakage tests now closes a chapter that had long worried engineers and policymakers.

For Munodawafa, it is not merely a technical victory but a strategic safeguard for millions who rely on the dam daily.

For Zimbabwe, the completion of Kariba’s rehabilitation could not be more timely.

The country’s peak demand is above 1,700MW, yet generation capacity has repeatedly fallen short, especially during droughts. Breakdowns at thermal plants such as Hwange have left businesses and households facing rolling blackouts that have stunted industrial output and undermined economic recovery efforts.

Mining companies, the backbone of Zimbabwe’s export earnings,  have warned that unreliable power supply raises costs, disrupts production, and discourages foreign investment.

The promise of a more reliable Kariba, producing low-cost hydropower, eases some of that pressure and provides a firmer platform for industrial growth.

For Zambia, the stakes are equally high.

The country has ambitions to become a net exporter of electricity within the Southern African Power Pool.

Already, Zambia sells power into the regional market when surpluses allow, but Kariba’s structural vulnerabilities have constrained that ambition.

With the dam now stabilised, Lusaka’s vision of deeper integration into regional power trade looks more realistic.

As Munodawafa put it: “Kariba is not just about electricity generation. It is about national security, economic stability, and regional cooperation. This project ensures that Kariba continues to be a pillar of resilience for Southern Africa.”

Yet while the dam’s structure is secure, hydrological risks remain. The Zambezi Basin has been buffeted by erratic rainfall patterns linked to climate change.

Extended droughts in 2019 and 2022 forced authorities to curtail generation at Kariba drastically, leaving both countries facing crippling supply gaps.

Analysts stress that even the strongest engineering cannot insulate the dam from inadequate inflows.

The rehabilitation buys time and resilience, but long-term energy security depends on diversifying generation into solar, wind, and thermal projects.

“The rehabilitation strengthens Kariba against structural failure, but it does not solve the climate problem,” said one Harare-based energy expert, Nyasha Nyoni.

“Governments must treat this as breathing space to accelerate investment in alternative energy sources.”

The rehabilitation carries symbolic weight beyond energy economics. Built in the late 1950s during the colonial Federation of Rhodesia and Nyasaland, Kariba was once a symbol of imperial ambition.

Today, it is jointly managed by independent Zimbabwe and Zambia through the Zambezi River Authority, serving as a rare example of cross-border cooperation in a region often marked by political discord.

The successful navigation of technical and financing hurdles also underscores the enduring value of multilateral partnerships.

In an era where global capital is increasingly contested, the willingness of institutions like the World Bank and AfDB to commit to Kariba reflects recognition of its strategic importance to Southern Africa.

For millions of households, the completion of the rehabilitation will not immediately eliminate load shedding.

Water levels remain vulnerable to climate cycles, and demand continues to outstrip supply. Yet the assurance that Kariba is structurally sound and able to continue producing the cheapest electricity available to Zimbabwe and Zambia, offers much-needed stability.

For Zimbabwe, where chronic shortages have deepened inflation and discouraged industrial investment, this is a reprieve.

For Zambia, it bolsters credibility as an energy hub and strengthens its export ambitions.

For the region, it secures a backbone facility whose failure would have been catastrophic.

Munodawafa captured this broader significance: “This project was about more than steel and concrete. It was about protecting the hopes of millions, securing livelihoods, and demonstrating what cooperation can achieve. Kariba is now secure for future generations.”

The Kariba Dam rehabilitation marks a rare success story in Southern Africa’s turbulent energy landscape.

It demonstrates that with international support, political will, and engineering expertise, existential threats to infrastructure can be overcome.

But experts warn that the next challenge looms: building resilience against climate volatility and diversifying energy systems to meet rising demand.

If governments use the window created by Kariba’s rehabilitation to accelerate renewable investments and improve grid management, the region could move closer to genuine energy security.

For now, however, the successful completion of the floodgate works provides a moment to celebrate.

As the waters of Lake Kariba lap against the renewed dam wall, the facility stands as both a technical triumph and a symbol of what cooperation can achieve in the face of daunting risks.

For Zimbabwe and Zambia, it ensures the continued flow of their cheapest and most vital power source.

For Southern Africa, it means the lights are less likely to go out.