A milestone has quietly slipped by at the Vaal Dam.
As of 20 February 2026, South Africa’s largest dam has remained above its full supply level for 350 consecutive days, a sustained run that, when measured against where the dam stood at the same time last year, highlights how dramatically the water picture has shifted.
According to the latest data from The Reservoir, a Water Resource Information Centre for the Catchment Management Forums of the Upper Vaal Water Management Area, the dam closed out the week at 100.50%, with inflows of 47.0 m3/s and outflows of 21.4 m3/s.
No sluice gates were open, an indication that, while levels remain above full supply, the pressure on the structure has eased somewhat compared to earlier in the week.
Week of gradual decline, but still comfortably full
The week of 16 to 20 February told a story of slow but steady retreat from a high point, though the dam remained well within comfortable territory throughout.
On 16 February, the dam sat at 101.13%, recording its highest inflow of the observed period at 89.6m3/s, nearly double the outflow of 21.4m3/s.
By 17 February, levels had steadied at 101.00%, with inflows tapering to 73.4m3/s while outflows held constant.
The following day, 18 February, saw the dam maintain its 101.00% reading even as inflows continued to slow, dropping to 60.9m3/s.
By 19 February, inflows had further retreated to 50.3m3/s, nudging the level down marginally to 100.80%.
The week closed on 20 February at 100.50%, the lowest reading of the five-day period, but still above the full supply level that water managers use as a key benchmark.
The Vaal Barrage, situated downstream of the dam, maintained a water level of 7.5 metres throughout the period.
Its outflows varied during the week, rising from 10.1m3/s at the start to 30.0m3/s on 16 February before returning to 10.1m3/s by the end of the observed period.
Water temperatures at the barrage ranged between 20.9°C and 23.0°C over the five days.
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Year-on-year turnaround that water managers will welcome
Perhaps the most telling figure in the week’s data is not what the dam sits at today, but where it was at the same time last year.
Around this period in February 2025, the Vaal Dam stood at just 63.4%, according to the Department of Water and Sanitation’s weekly report on the provincial state of dams.
The recovery since then, more than 37 percentage points, reflects a sustained wet season that has kept the dam brimming for the better part of a year.
Even the comparison with last week underlines how stable conditions have been.
The Department of Water and Sanitation’s report placed the dam at 101.5% the previous week, meaning levels have dipped only marginally over the seven-day period, a sign that inflows, while slowing, have been sufficient to keep the dam effectively full.
350 days and counting
The 350-day streak above full capacity, while not accompanied by the dramatic scenes of open flood gates and surging spillways that South Africans witnessed during wetter periods, represents a sustained period of water security for the millions of people who depend on the Vaal system.
The dam supplies water to Gauteng, the Free State, and parts of the North West and Mpumalanga provinces, making its level a matter of national significance.
With inflows still positive, albeit declining through the week, and no gates open, the system appears to be managing volumes comfortably as the late summer rainy season begins to wind down.
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