Water levels remain above full capacity despite a small decline from last week.
As the rainy season sets in, the Vaal Dam’s water level has decreased marginally this week, according to the Department of Water and Sanitation’s weekly provincial report released on 29 September.
The dam now stands at 102.3%, down from 103.6% the previous week.
The slight drop still represents a dramatic improvement from the same period last year, when the dam stood at just 40.9%.
Current Vaal Dam statistics
According to the latest measurements from The Reservoir, a Water Resource Information Centre for the Catchment Management Forums of the Upper Vaal Water Management Area, the dam recorded a level of 102.40% on 1 October 2025.
The facility is currently receiving an inflow of 93.2 cubic metres per second while releasing 16.8 cubic metres per second as outflow.
The Vaal Barrage maintained a level of 7.5 metres with an outflow of 44.6 cubic metres per second.
Water temperature at the barrage measured 17.8°C on 1 October.
On the previous day, 30 September, the barrage recorded the same level but a significantly lower outflow of just 10.1 cubic metres per second. The water temperature was slightly cooler, at 17.3 °C.
Historical comparison
The dam stood at 102.27% on 30 September 2025, showing a downward trend from the previous day.
Additionally, the dam recorded an inflow of 85.1 cubic metres per second, lower than the following day’s measurement. The outflow remained constant at 16.8 cubic metres per second on both days.
Historical data for 30 September reveals significant year-on-year variations. In 2024, the level was 41.43%. The Vaal dam reached 80.30% in 2023 and 94.60% in 2022.
Earlier years showed 83.30% in 2021, followed by a particularly low 33.30% in 2020. The facility measured 54.70% in 2019 and 88.59% in 2018.
In 2017, the level stood at 85.06%. The year 2016 saw one of the lowest recordings at 29.56%, while 2015 registered 60.04%. In 2014, the dam was at 81.31%.
All historical levels for 30 September showed downward daily trends across the years measured.
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