Major Kariba Dam rehabilitation to end in 2025

BY NOKUTHABA DLAMINI 

The Zambezi River Authority (ZRA) says the on-going Kariba Dam Rehabilitation Project (KDRP) will be completed in 2025 with the reshaping works involving excavation of rocks in the plunge pool to facilitate its stabilisation now underway.

ZRA said the implementation of the KDRP, which comprises reshaping the plunge pool and refurbishment of the spillway gates will be done in phases.

The authority 60 percent of the works have already been done and this has  ensured sustainable generation of power in Zimbabwe and Zambia.

“Works on the reshaping of the Plunge Pool have been progressing well,” ZRA said in a statement on Monday.

“The reshaping works involve bulk excavation of the rock in the existing pool to facilitate the stabilisation of the plunge pool and prevent further scouring/erosion along the weak fault zone towards the dam foundation.

“This will be achieved through construction of a temporary water-tight cofferdam to facilitate the reshaping works under dry conditions.

” The plunge pool reshaping works, which commenced in May 2017 are scheduled for completion by the end of 2024.”

ZRA said despite some delays encountered during implementation, in particular the unforeseen geological complexities, the project remained on course to be completed on schedule.

“The spillway refurbishment works are also progressing well,” the authority said.

“These works are meant to replace secondary concrete and built-in-parts of upstream guide slots of the stop beams and ensure free movement of the electromechanical equipment that is used to block the flow of water from the upstream face of the dam wall.

” An emergency gate for closure of sluices under  emergency conditions (to be used where a gate fails to close after release of excess flood  water) is also under manufacture.”

The rehabilitation of the Kariba Dam will be completed in 2025

The spillway refurbishment works, which commenced in November 2019 and

Are being implemented by a consortium of GE Hydro and Freyssinet International of France are targeted to be completed in January 2025.

ZRA said while consistent measures have been adopted and implemented to mitigate the effects of Covid-19 on KDRP, the project has not been spared as it still suffered some considerable impact in respect of site arrangements, offshore supplies and logistics.

” The impacts include loss of time due to returning expatriates and other local employees having to be quarantined each time they were diagnosed positive,” it added.

“Furthermore, the owner and owner’s engineer failed to timely witness the factory acceptance tests and vendor quality surveillance for project equipment before such equipment could be approved and shipped to the project site.

“The prevalence of the pandemic also led to tightening of border crossing restrictions resulting in traffic congestion, which impacted the project and hence impeding timely delivery of project equipment.”

The authority said such disruptions resulted in both time and cost overruns against the project baseline schedule and budget, respectively.

ZRA is a bi–national organisation mandated by the governments of Zambia and Zimbabwe to sustainably harness the hydropower potential offered by the waters of the Zambezi River for socio-economic and industrial development of the two countries.