Department assures Vaal Dam’s low level is ‘no cause for panic’

A dam once bustling with boats ferrying sightseeing tourists lies dry, its ground parched and marked with cracks.

At a 28.62% capacity, the Vaal Dam is too low for boats to cruise.

A dry summer and a heatwave, worsened by maintenance work on the Lesotho Highlands Water Project that began on October 1, had led to the dam running dry, said Kathy Manten, owner of Manten Marina in Deneysville, Free State. 

Manten Marina operates several boats on the Vaal Dam.

Manten said the challenges stared last summer.

“It’s been a very dry and hot year and the storms that do come don’t help because they may damage the boats if they go out. With the heat, the drought and the closure of the water plant, it’s like the perfect storm,” she said.

However, a water analyst and the department of water & sanitation on Monday said there was no need to panic.

“We have enough water. Once the level sits at 18%, which is the minimum operational percentage, we would open the Sterkfontein Dam to supply water to the Vaal. The Sterkfontein Dam has enough water. There is no cause for alarm,” said department spokesperson Wisane Mavasa.

“The reason there is a low level at the Vaal is because we have closed the Lesotho stream due to the work being done in the area. We have not had rain and the Vaal Dam loses most of its water to evaporation,” she said. 

Manten said that once the stream from the Lesotho project was cut off “the water dropped drastically. Now we are heavily reliant on rainfall, which is rare.”

The Lesotho Highlands Water Project is undergoing essential maintenance on its tunnel system, with work expected to be concluded on March 31 2025.

A resident who asked not to be named said households were not affected by the dam’s low levels.

Prof Mike Muller, an expert engineer specialising in the structural design of water systems, said there was no need to be  concerned about the water level at the dam.

“The Vaal Dam is just one of the 14 dams in the system, so we don’t worry about the levels at the Vaal Dam, but rather about how much water there is in the whole system.

“The Vaal Dam loses a lot of water because it is very shallow and when it gets hot, it evaporates, and the levels fall. If the water level is at 20%, that’s good because that means we will not lose so much water to evaporation,” he said.

However, he said if the dry weather continued, then a problem could arise.

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