Another Flood Warning ! Orange River 02 Feb 2011

[Michael Alexander]

Upington - An urgent flood warning was issued to communities downstream of the Orange River, in Upington in the Northern Cape, by the Department of Water Affairs on Wednesday.

It was predicted that with a water flow of 5 100 cubic metres a second (m3/s), the Lower Orange River, it would reach a height of 7.7 metres in that area at midday on Wednesday, spokesperson Linda Page said.

She said this level was about 0.1 metres lower than the peak that caused widespread flooding in January.

Dams overflowing

The department was still monitoring the situation at the four largest dams in the Vaal and Orange River catchments.

The Vaal Dam was at 106% full, with six floodgates open and an outflow of 770 m3/s.

At the Bloemhof Dam, a capacity of 100% had been reached with outflow of 1 400 m3/s and it was expected to remain stable until next week, Page said.

She said the Gariep Dam was 115% full and decreasing steadily. Its outflow was 2 000 m3/s. The capacity of the Vanderkloof Dam was 114% with an outflow of 2 500 m3/s.

In the Lower Orange River, the department recorded the flow at Katlani, which is the Orange-Vaal River confluence, at 4 600 m3/s.

About 4 910 m3/s was recorded at Prieska, which peaked at 5 050 m3/s on Tuesday.

Rain expected

The predicted high flow in Upington was 5 100 m3/s on Wednesday.

The predicted high flow at Brand Karos, near Alexander Bay, for Saturday was 4 900 m3/s.

Page said the SA Weather Service was predicting a 30% chance of showers and thundershowers in the next 24-hours in the Upper Vaal River catchment and a 60% chance in the Middle Vaal River.

She said a 60% chance of showers and thundershowers in the next 24 hours was also predicted in the Orange River catchment upstream of Douglas.