Maputo — The Zambezi River Authority (ZRA), which operates the Kariba dam on the Zambia/Zimbabwe border, on Monday opened one of its floodgates.

This was expected, since the ZRA had given notice of its intentions over a week earlier. However, according to a source in the Mozambican government's relief agency, the National Disasters Management Institute (INGC), the flood gate has only been opened 50 per cent, adding an extra discharge of 750 cubic metres of water a second into the Zambezi.

It is not yet clear what effect this will have on the Zambezi in Mozambique. AIM's source said there is still some capacity for storage in the Cahora Bassa lake, so the impact of a new flood surge from Kariba will at least be dampened.

The Cahora Bassa dam is currently discharging 4,000 cubic metres of water a second into the Zambezi. Should it be forced to increases these discharges, that will add to the pressure on the flooded areas on the lower Zambezi.