To gain an understanding on the formation of the Okavango Delta and its annual flood patterns it may be helpful to look at the origin and flow of the Okavango River.
The source of the Okavango Delta flood actually lies in the extremely wet highlands of Angola north of Botswana. From here the Okavango River flows south through Namibia away from the sea. It forms part of the border between Angola and Namibia, and then flows into Botswana, where the river becomes known as the Okavango River. Channelled by ancient fault lines, the precious live giving waters begin the meandering journey.
Before the water enters Botswana, the river drops 4 meters in a series of rapids known as Popa Falls, visible when the river is low, as during the dry season. The Okavango River continues on and splits into several channels, forming a vast, fan-shaped, astonishingly vibrant wilderness of flood plains, forests, smaller streams and an array of lagoons, islands and channels, which is commonly known the Okavango Delta. This area is some 15 000 km2!
People tend to get confused by the fact that all of Botswana, including the Okavango Delta, has a summer rainfall, yet the flood occurs in the dry winter months. Summer rain falls first seep into the parched ground before the rivers start flowing. The rainfalls in the highlands gather momentum up North and slow down as they reach Namibia. Attributed to the shallow gradient of the land and the swamp vegetation slowing the water down, the flood travels very slowly at only one kilometre a day and it takes months for the flow of water to reach the actual Okavango Delta. During late April the flood usually arrives into the northern reaches of the Okavango Delta making its way steadily down reaching many camps only sometime in June, or possibly early July, depending on their precise location, reaching its peak sometime in August. August is Botswana’s dry winter season and this is what attracts the animals to the water. Some animals even become trapped on the larger islands- making game viewing spectacularly simple.
The weather in Botswana is very warm and the flood-water will gradually evaporate and trans evaporate over the next few months, depositing its rich river salts and minerals into the ground as channels and lagoons dry up. It is the only inland Delta in the world. The rivers were cut off from the sea thousands of years by earthquakes that shifted tectonic plates and created fault lines that ‘’trap’’ the flow of the water.
These ideal circumstances provide the perfect breeding ground for an incredible diversity of wildlife, which is drawn from all over Botswana to the abundant water in the dry winter months. Therefore it is no surprise that the Okavango Delta was named as one of the Seven Natural Wonders of Africa and declared a UNESCO World Heritage Site.
The excellent rains that have fallen in Angola these past months has resulted in the water levels in the Okavango River rapidly rising with a lot more still to come. It looks like the Okavango Delta's veins will flow well this year. Visitors are sure to hear the sounds of whistling ducks, reed frogs, squacco herons and the soft splash of lechwe trotting through the shallow flood plains.
To date the 2020 flood levels are at their highest at this time of year for at least the past 5 years. The below measurements have been provided by Hydrology Namibia and were taken at their measuring station at Rundu, just before the Okavango River flows into Botswana. On the 2nd of March 2020 the rainfall was sitting at 7.61m at Rundu – last year we were at 5.08m and the average per year is 5.80m.
We are very excited for an amazing flood this year. Those of you that experienced the delta in one of its driest phases last year, visit the Okavango Delta this year, it's going to be epic! For more information or for sample itineraries showing how the Okavango Delta can be incorporated into a package, please contact us.