For time millennia, the levels of the Zambezi River has ebbed and flowed with the changing of the seasons. Read on to find out more how the highs and lows of the river are tracked, and what is “normal”…
How is the water over the Victoria Falls measured?
The Zambezi River Authority was established in 1987 and is the body that monitors water flow along the Zambezi River to Kariba, through its hydrometric network. There are thirteen stations along the river where water levels are monitored daily – one being the Victoria Falls/ Big Tree station.
What are the Annual Variations of Water Flow?
In Victoria Falls, there is the high water season from March to May when the Falls is at the highest and the low water season from September to December when the Falls are at their lowest. How much water is flowing over the Victoria Falls is due to the rainfall in the catchment areas further upstream in Zambia, Angola and Botswana.
If you take a look at this sunrise series taken by Ilala Lodge Hotel, you can tell the difference in water flow during high and low water season. Here is a comparison between October 2019 and March 2020. You can expect the water levels to start to rise in December and January in most years.
What do the Records say?
The maximum flow recorded at Victoria Falls was during the early construction phase of Kariba Dam in March 1958 at 10,000 cubic metres per second. The lowest flows recorded to date at Victoria Falls were during the 1995/96 season which had an annual mean flow of 390 cubic metres per second, whereas the Long Term Mean Annual flow at Victoria Falls is 1,100 cubic metres per second.
2019 was one of the driest on record, but not the lowest as the water flow was an estimated 3cm higher than the lowest level recorded back in 1995. The rainfall in 2020 so far has been good, and the volume of the Zambezi River flowing over the Victoria Falls has continued to increase steadily and was measured to be 2,520m3/s on 19th March 2020. Last year on the same date, the flow was 800m3/s which means the Zambezi River flows at Victoria Falls are above the long-term mean!