The dam's gates remained firmly shut.
Picture; Nigel Sibanda
The Vaal Dam continues to hold above 100% capacity, with daily inflows consistently outpacing releases as water managers keep spillage controlled heading into winter.
Vaal Dam holds steady
The Vaal Dam remains well above its full supply level, sitting at 107.17% on 27 May 2026, 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.
This follows a marginal decline from the 107.30% recorded on both 25 and 26 May, and a recent high of 107.56% on 24 May.
“Level: 107.17%,” The Reservoir reported on 27 May, with inflows recorded at 68.4 m³/s against an outflow of just 3.8 cubic metres per second.
The dam’s gates remained firmly shut, with zero gates open.
The Reservoir noted that inflows on 24 May stood at 75.0m³/s, even as outflows were kept low at 3.8m³/s with no gates open, pushing the level to its highest point in the reported period at 107.56%.
Brief release on Monday
A notable shift occurred on Monday, when dam managers opened one gate and significantly increased outflows to 119.6m³/s even as inflows reached 72.0m³/s.
The Reservoir confirmed the dam level held at 107.30% despite the elevated discharge.
“Outflow: 119.6m³/s. Gates Open: 1,” The Reservoir reported.
By Tuesday, the gate had been closed again, with outflows dropping back to 3.8m³/s.
The data reflects a consistent operational pattern over the period. “Level: 107.30%. Inflow: 65.6m³/s. Outflow: 3.8m³/s. Gates Open: 0.”
Vaal Barrage remains stable with steady outflows
Downstream, the Vaal Barrage maintained a consistent water level of 7.4 metres across all four days of the reporting period.
Outflows were stable at 5.0m³/s on 24, 26 and 27 May, spiking to 103.7m³/s on 25 May.
“Outflow: 103.7m³/s,” The Reservoir recorded at the Barrage on 25 May, reflecting the downstream pass-through of the controlled release from the main dam.
The swift return to 5.0m³/s the following day underscores the efficiency of the coordinated management between the two structures.
Water temperatures at the Barrage remained in the low-to-mid teens throughout the period.
“Water Temp: 14.4°c,” The Reservoir reported on 27 May, while the lowest reading of 13.8°c was logged on 26 May and the highest of 14.7°c on 24 May.
