Water Levels In Botswana
A Miracle of Nature – the Okavango Delta and its changing water levels
The Okavango Delta is a very unique part of the world. Looking at a satellite image you can easily see a few blue lines meandering from the Angolan highlands all the way to Botswana, forming a magnificent river that spreads into an alluvial fan and then simply disappears. It creates an amazing oasis in the middle of the world’s biggest stretch of sand, the Kalahari, reaching from Congo to South Africa. Magic. But the true magic is in the timing of the flood!
Rainy season in the catchment area and around the Okavango usually begins in November, with the majority of rain falling in January and February. The local rainfall only contributes to between 2 and 25% of the delta waters, the majority of water is coming down from the Angolan highlands.
If we traveled with a little drop of water from the source of one of the main contributories, the Cubango and Cuito River in Angola, the start of our journey would be quite exciting, through the Angolan highlands and then down to Botswana, but even before we’d cross over the border we’d already travel at a rather leisurely pace simply due to the lack of gradient. It takes this little drop of water average 8-9 weeks to reach Botswana and the panhandle of the Okavango Delta. From here onwards the journey slows down even more: the northern part of the Okavango is 250 km away from the Thamalakane fault line – the delta’s southern border – but there is only a difference of 50 meters in altitude!
The main waters reach Botswana in April and start to spread throughout the alluvial fan slowly filling up the channels, backflows and floodplains, with the delta being at its fullest in July/August. From August onwards the water levels start going down again due to evapotranspiration now exceeding the input by rain waters. The driest period in the delta is in October and November, when food is scarce and animals are found around the remaining water sources and rivers. Many channels have dried up, avid birders can’t get enough of all the bird life gathering around fish traps as the water keeps receding and cars can be used where just a few months ago boats were necessary to get around. Just then the first rains fall again, the shades of brown start turning into shades of green once more, impala and other antelope drop their young and the cycle starts over – the Okavango becoming a place of plenty. The water levels in the heart of the delta though will only rise significantly once the rains have long gone.
So what does this mean for us selling the destination?
This region is highly dynamic and each year presents a varying amount of flood water in winter and a varying amount of rainfall in summer. With nature, water levels provides a certain amount of unpredictability and nobody knows what will happen from one year to the next.
A well-rounded Botswana Safari consists of game drives in drier areas and also water activities, be it by boat or mokoro. Mekoro are ideal to travel over floodplains in shallow water, gliding through reeds, discovering the little hidden gems of the area. Once the floodplains have fallen dry it becomes difficult to offer mokoro excursions due to safety concerns in deeper waters of permanent channels and rivers. Even if those deeper waters are actually not that deep anymore, they are considered prime real estate amongst hippos, who are in not that great a mood, as their territories are shrinking with the receding water and they are now very much up close and personal with their competitor and neighbour.
It is far easier on the nerves to observe those dynamics from a motor boat, but be aware that cruises can be a lot shorter due to a lack of either depth or river altogether! Some camps may not be able to offer mokoro during very low flood levels, so please understand that all water activities are water level dependent. The camps shift their focus. The floodplains may not be ideal for mokoro anymore, but they provide wonderful grazing for herds of buffalo amongst other game and the floodplains fill up with big herds of lechwe, enjoying the greenery so different experiences are always ready to reveal themselves. Other camps might not be that heavily affected and still happily take their guests on mokoro excursions and motor boat activities. Your itinerary expert can advise you on water levels, dependent of the time of year that you have requested for travel.