-But there won’t be much of it
Expectations are that the flood water will wash into Maun’s Thamalakane River in three weeks’ time. There has been a lot of excitement as expectations grew by day, the anxiety of it all being the arrival date of the water at the Boro –Thamalakane river junction.
Okavango Research Institute (ORI) Researcher and Meteorologist Mike Murray-Hudson told The Ngami Times this week that the flood, anticipated to reach Maun mid-June will not be extensive as indicated by the volume that passes through at Mohembo.
Thamalakane River is fed by the Boro system. He revealed that about a week ago, they received information that the water had passed Nxaraga hence the expectations that the water will soon be reaching Maun.
“It’s very difficult to say what will happen but usually when this river system dries up completely the incoming water gets to fill up the soil first before it can flow further, and it might be that there was lot of dry soil, so we don’t know how quickly it is going to come,” Murray-Hudson explained in an interview.
He has however indicated that in the last rainy season (from September to April) there were good rains over the delta hence currently there is still water coming from Gomoti and Santantadibe river systems which are on the east side of chiefs island.
This, he explained then means that a least when the floods arrive the rainfall water in the two river systems will not take long to rise. According to him, the rate of water flow at Mohembo is about 65% of the flood that can be expected while the remaining percentage is generated by rain that would have been experienced over the delta.
“Usually the water moves at less than one meter per second especially on the Boro side but if you go to Mohembo at the peak flood its moving faster than that (might be 1.2 per second),” Murray-Hudson explained concluding that the water is probably moving at a pace of half a meter per second. The Acting ORI Deputy Director further revealed that this year’s flood is better than the ones of the past two years.
Murray-Hudson was however doubtful that the Kunyere system which feed into the Lake Ngami is going to carry water this year. Should that happen the researcher believes the water won’t be that much.
He has however indicated that this year’s flood won’t be extensive as the previous ones noting that they anticipate for it to be lower than in the previous years.
Meanwhile Hudson explained the high variation in timing and amplitude of the flood over the years and decades, highlighting the importance of variation in maintaining the productivity and biodiversity.
He further added that; “as long as the variation in water flow is maintained, the river system is highly resilient and capable of adapting to changes and given the complexity of the system, which may be affected by weather on the other side of the globe, such events can have far-reaching consequences for the topography and flow pattern of the river.”
Meanwhile the incoming flood is expected to improve the Maun’s water supply as the river had dried up forcing the Borolong Water Treatment Plant to cease operations leading to water shortages. The development is also expected to improve the local economic livelihoods for mokoro polers, boat-cruise operators, farmers and fishermen.