Lake Kariba water levels on upward trend

Lake Kariba’s water levels are on a steady upward trend, supported by sustained inflows from key upstream stations on the Zambezi River, according to the latest hydrological data for the week ending 5 May 2025.

The gradual but consistent rise signals renewed optimism for regional hydropower generation and water security, following a relatively subdued start to the 2024/25 season.

Lake Kariba Levels Improve to 15.15% Usable Storage.

As of 5 May 2025, Lake Kariba’s water level had risen to 477.68 meters, representing 15.15% usable storage, up from 13.95% just a week earlier on 29 April. This figure also exceeds last year’s level of 477.42 meters (13.31%) recorded on the same date.

The lake, which is designed to operate between 475.50m and 488.50m, has seen incremental increases daily, reflecting strong upstream flows on the Zambezi system.

Daily Lake Levels (2025):
-29 April: 477.51m (13.95%)
-1 May: 477.56m (14.30%)
-3 May: 477.63m (14.79%)
-5 May: 477.68m (15.15%)

Though still far below the Flood Control Rule Curve, the rising trend suggests an improving outlook for hydropower output, particularly for the Kariba South Power Station.

Zambezi River Flow Patterns: Chavuma Slows, Victoria Falls Strengthens.

Daily monitoring across key hydrometric stations—Chavuma, Ngonye, and Victoria Falls—shows mixed trends:

?Chavuma Station:
Flow at Chavuma decreased from a peak of 3,103 m³/s on 30 April to 2,584 m³/s on 5 May. This still far exceeds last year’s flow of 774 m³/s on the same date, confirming a stronger runoff season despite recent declines.

?Ngonye Station:
At Ngonye, river discharge remained strong, peaking at 3,014 m³/s on 2 May before slightly easing to 2,982 m³/s by 5 May. This compares favourably to 880 m³/s recorded on 5 May 2024.

?Victoria Falls (Nana’s Farm):
Victoria Falls continued its upward trajectory, recording 2,635 m³/s on 5 May, compared to 735 m³/s last year. This flow is well above the long-term mean annual flow of 1,100 m³/s, underscoring robust hydrological input into the Kariba catchment.

Hydrological Outlook.
The upward movement in both lake levels and river flows is a positive development for regional water managers and energy planners. However, storage levels at Lake Kariba remain below average, and continued monitoring is essential as the dry season approaches.

The 2024/25 season, while stronger than last year, is still tracking beneath several historical benchmarks, as shown by hydrological benchmarking curves. Nonetheless, projections for 2025/26 suggest further recovery by December, provided upstream conditions remain favourable.

The Zimbabwe National Water Authority (ZINWA) and the Zambezi River Authority (ZRA) are expected to maintain tight coordination in managing dam releases, energy output, and downstream water needs.

Rising lake levels and strong Zambezi inflows mark a welcome development for Zimbabwe and the region, especially given the importance of Lake Kariba for power generation and regional water supply. While the situation remains below optimum, the current trend offers a strong foundation for improved hydrological performance in the coming months.

Zimbabwe Economic Review