Villagers around Masinga Dam and those downstream along Tana River must now move away because the dam is overspilling, having reached its highest levels on Thursday, Kengen has said.
In a statement, the Kenya Electricity Generating Company said the water level at Masinga rose to 1,058.22 metres above sea level on Thursday, against a full supply level of 1,056.50 metres.
The highest level ever recorded was 1,058.13 in May 2020.
The dam started overflowing late last month and the spillover will now be heavier and more ferocious.
Kengen managing director Eng Peter Njenga said they had warned villagers as early as November last year that the dam would likely reach full supply capacity and overflow in April 2024, which has come to pass.
At that time, Kengen advised communities living near the dams and along River Tana to relocate and move to higher grounds to avoid loss of lives and property.
“The communities residing in Mbondoni location, Kithecu, and Menguthe villages are particularly at risk. Given the current circumstances, we must prioritise the safety and well-being of our citizens.” Njenga said.
Flooding by River Tana usually affects lower Embu, Kitui, Garissa, Tana River and Kilifi counties.
Ministry of Interior confirmed many of the villagers have moved and are sheltering in schools.
“There is need for food, medical kits and non-food items to counties where search and rescue operations are still ongoing including Nairobi, Kirinyaga, Homa Bay and Tana River,” Interior ministry said in a statement.
It also said a lot of public infrastructure in these regions has been destroyed.
“Taita Taveta, Kitui and Tana River require massive post-flood recovery initiatives in public works, the reconstruction of schools, repairs to water treatment systems, road repairs and improvements to the accessibility of social and economic facilities,” the ministry said.
Kengen said Masinga’s water levels will remain high for most of this month as the ongoing rains persist as forecasted by the Kenya Meteorological Department.
Masinga dam straddles the border of Embu and Machakos counties and is part of the Seven Forks Cascade that include Kamburu, Gitaru, Kindaruma and Kiambere.
Kengen said all these large hydropower dams in the Seven Forks have reached full supply capacity.
“The Seven Forks dams hold the bulk of the water flowing from River Tana, way more than half the volume, which would otherwise be flooding areas downstream of the dams thereby reducing the damage caused by the ongoing rains,” Njenga said.
He said there’s no chance of any calamity at the Seven Forks dams because of the huge amounts of water they are holding.
“We constantly monitor our dams’ structure and would wish to assure all Kenyans that the dam safety measures we have put in place along with our disaster preparedness help allay risks of the water breaching the walls of the dams,” he said.
The dams usually help to regulate river flows and mitigate flooding downstream by temporarily storing the flood volume and allowing the water to naturally flow downstream later through the power plants.
Njenga said Kengen is considering raising of Masinga Dam by 1.5 metres, which will help hold more water and further delay the overflow of the dam during heavy rains.