Three sluice gates are set to be opened at the Vaal Dam on Tuesday to manage water levels after heavy rain. These releases have further sparked concerns of possible evacuations
Five gates were already opened on Monday, as the dam surged to 109.26% capacity.
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 three gates were scheduled to be opened at 10am, 12pm and 2pm on Tuesday.
WATCH: Five sluice gates opened at the Vaal Dam on Monday.
This will bring the total number of open gates to eight.
The dam is currently receiving inflows of 883.4m³/s while discharging 727.0m³/s.
The Vaal Barrage, meanwhile, recorded outflows of 1 137.4m³/s with the water level at 7.5 metres and a temperature of 18.2° Celsius.
Evacuation warning
The high water levels have prompted authorities to issue evacuation warnings to residents living in low-lying areas in the Vaal Triangle. Residents and businesses along the Vaal River face potential flooding as controlled releases continue.
“Action Required: Residents and businesses along the Vaal River—especially in low-lying areas—are strongly advised to remain vigilant, heed all evacuation warnings, and remove any valuable assets from the riverbanks immediately as controlled releases are active,” a notice said to have been sent by the Department of Water and Sanitation (DWS) to residents read.
Midvaal councillor Pieter Swart confirmed the likelihood of water exceeding the riverbanks.
“There is a high chance of overflowing the riverbanks. The people who were previously affected will be affected again,” Swart told The Citizen.
He emphasised the risks facing properties built in flood-prone areas.
“Property and infrastructure built within the 1-in-100-year floodline are considered to be at risk. The DWS’s priority is dam and flow management, not guaranteeing the safety of assets in known flood-prone zones,” Swart added.
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Managing water
Swart explained that both the Vaal and Bloemhof Dams are actively managing the situation to ensure system safety.
“The Integrated Vaal River System (IVRS) is experiencing high inflows. Both the Vaal and Bloemhof Dams are actively managing outflows to ensure system safety and continued water security for Gauteng,” Swart said.
The Vaal Dam is utilising strategic surcharge capacity, having risen from 107.43% on Monday to its current level of 109.26%.
On Monday, the dam recorded significantly higher inflows of 962.2 cubic metres per second but much lower outflows of just 63.4 cubic metres per second, before authorities ramped up controlled releases.
At Bloemhof Dam, which stands at 99.62% capacity, authorities have been instructed to increase flows to 600 cubic metres per second starting at 10am on Tuesday.
The dam is currently discharging 400.39m³/s as it manages its own high inflow levels.
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