Lake Kariba water levels on upward trend

Water levels at Lake Kariba and key flow stations along the Zambezi River have shown a steady increase over the past week, indicating a positive hydrological outlook for the region’s power generation and ecosystem balance.

This rise is attributed to improved inflows from upstream catchments amid seasonal rainfall patterns.

Lake Kariba Levels: Modest but Steady Rise.

Lake Kariba, designed to operate between 475.50 meters and 488.50 meters (with a 0.70m freeboard), recorded a water level of 477.51 meters on 29 April 2025, translating to 13.95% usable storage.

This marks a slight increase from 477.44 meters (13.45% usable storage) on the same date in 2024.

Throughout the review period from 23 to 29 April 2025, lake levels gradually rose:

23 April: 477.39m (13.10%)
25 April: 477.43m (13.38%)
29 April: 477.51m (13.95%)

Despite this improvement, the lake remains significantly below mid-capacity, emphasizing the need for continued monitoring and prudent management of the resource, especially for hydropower operations.

Zambezi River Flows at Key Stations Surge Significantly.

1. Chavuma.
   Flows at Chavuma station experienced a substantial increase during the review period, closing at 3,065 m³/s on 29 April 2025 — more than triple the flow recorded on the same date last year (916 m³/s). The consistent daily rise reflects healthy upstream contributions:

23 April: 2,610 m³/s
25 April: 2,597 m³/s
29 April: 3,065 m³/s

1. Ngonye Falls.
   A similar upward trend was recorded at Ngonye, with flows reaching 2,970 m³/s on 29 April 2025, compared to 834 m³/s in 2024. This steady increase underscores the resurgence of river health in this midstream stretch.

2. Victoria Falls (Nana’s Farm Station).
   At one of the most critical observation points on the river, flows rose from 2,352 m³/s on 23 April to 2,498 m³/s on 29 April 2025.

This is a significant leap from 711 m³/s on the same date last year and remains a key indicator of catchment inflows into Lake Kariba.

Historical Context: Long-Term Flow Patterns.
The Zambezi River’s long-term mean annual flow at Victoria Falls is 1,100 m³/s. While current flows are well above this average, historical extremes provide a deeper perspective:

Highest flow: ~10,000 m³/s in March 1958 (during Kariba Dam’s construction).

Lowest flow: 390 m³/s during the 1995/96 drought season.

Conclusion
The latest hydrological data reveals encouraging signs for Lake Kariba’s water levels and the broader Zambezi basin.

With river flows increasing at all major stations, some surpassing triple their 2024 levels, water managers and regional energy planners can look forward to improved reservoir replenishment.

However, despite these gains, the lake’s usable storage remains under 14%, underscoring the need for sustained inflows to secure power generation and water resource sustainability.

Zim Economic Review