2020 Okavango Delta Flood is on its way

Posted on 5th February 2020

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 (known here by its Portuguese name Rio Cubango)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.

Before it enters Botswana, the river drops 4 m 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, which is commonly known the Okavango Delta. 

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. 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 some time in August. August is Botswana’s dry winter season and therefore the flood-water will gradually evaporate over the next few months, depositing its rich river salts and minerals into the ground.

These ideal circumstances provide the perfect breeding ground for an incredible diversity of wildlife. 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.

The below graph (courtesy of the African Guide Academy) detailing the Okavango River water levels at Rundu (capital of the Kavango-East Region in northern Namibia – refer to above map) shows a significantly earlier first peak than last year (last year also being the first in many years where only one peak could be observed). This early larger volume of water promises to deliver a second peak, which should bring a decent volume of water into the Okavango Delta later this year – meaning the flood is on its way.