Chronicle Editor
Walter Nyamukondiwa, Harare Bureau
More water is now flowing into Lake Kariba than this time last year with the Victoria Falls measuring station recording 340 cubic metres a second flowing down the Zambezi on Tuesday compared to 290 cubic metres a second at the end of 2017 and just 224 cubic metres a second at the beginning of December.
Almost all water flowing over the Victoria Falls and into Lake Kariba comes from rainfall in eastern Angola and western Zambia, with only trivial flows from northern Zimbabwe and southern Zambia.
The rising flows into Lake Kariba will allow the two power stations to continue generating at low levels even if they are unable to access any more stored water.
There is now very little stored water in Lake Kariba above the dead water level, the minimum to operate the two power stations, following a drop in the lake level of 41cm in December, meaning the moment is fast approaching where the two power authorities can only use what is actually flowing into the lake, minus evaporation losses.
Usable storage for power generation has dropped from 11,5 percent of total storage capacity over the dead water level at the beginning of December to about 8,23 percent by month end.
Satellite imagery from America’s NASA space agency shows lake levels have dropped to their lowest level since 1996. In the images, NASA compares the state of the lake on the same day in November and December 2018 and 2019 showing vast swathes of land that were under water now laid bare including rock outcrops and islands.
Receding water levels have also affected the abstraction of water by local authorities including Kariba Municipality resulting in some areas going for more than a month without supplies. While there is still a lot of water in the lake below the dead water level, the intakes for the municipality do not go far enough down.
The Breezes Intake Tower is now exposed and unable to draw enough raw water to feed the treatment plants.
Areas such as Nyamhunga, Baobab Ridge and Batonga suburbs have not received water in recent weeks while others are getting intermittent supplies.
Council has had to buy pumps and install them further into the lake where they will not be clogged by sand.
Online Reporter