Maputo — Swollen by heavy rains in central Mozambique and in neighbouring countries, the Zambezi river reached flood warning level on Wednesday at several points, according to the National Water Board (DNA).
At Zumbo, on the border with Zimbabwe, the river rose from 4.78 metres on Tuesday to 5.4 metres on Wednesday morning, considerably higher than the flood alert level of five metres.
Further downstream, at Mutarara, the rise over the same period was from 4.57 to 5.05 metres, and at Caia, the rise was from 4.73 to 5.13 metres. At both these measuring stations, the flood alert level is five metres.
No information has reached the DNA from the Marromeu station, the last one before the Zambezi delta, but, given its proximity to Caia, it seems safe to assume the flood alert level of 4.75 metres here has been reached or exceeded.
At Tete city, the river is not yet in flood, but it has continued to rise ominously, reached 4.87 metres on Wednesday morning, just 13 centimetres below the alert level.
The seriousness of any flood on the Zambezi depends heavily on the behaviour of the Cahora Bassa dam. The dam lake is capable of storing vast quantities of water - but it is nearing its full capacity.
Measured at the dam wall, the lake rose from 323.77 metres on Saturday to 324.15 metres on Monday. When that reading reaches 326 metres, the lake is regarded as completely full.
The dam management has increased discharges from the lake from 1,569 cubic metres a second on Monday to 1,749 cubic metres a second on Tuesday. Despite this increase, most of the water entering the lake is being stored there: the inflow into the lake was measured at 5,254 cubic metres a second on Tuesday.
Another river causing concern is the Licungo in Zambezia province. Heavy rains in the Licungo basin pushed the height of the river, measured at the town of Mocuba, to 6.7 metres. This is well above the alert level of six metres, and the DNA expects the Licungo to continue rising over the next 24 hours.
In Sofala province, the river Buzi remains above alert level. The river was measured at 5.75 metres high at Goonda (where the alert level is five metres) on Wednesday, and since rain is continuing in the region the river is bound to go on rising.
Most of the rivers in the south of the country are subsiding. But the Incomati, measured at 5.29 metres in Magude, in Maputo province, remains above the flood alert level of five metres.