The Engineering Institution of Zambia says there is no imminent collapse of the Kariba Dam.
EIZ Vice President for Policy, Public Relations and National Development George Sitali told a media briefing that the state of the dam report shows the dam is not under an imminent collapse.
Mr Sitali said the report also demonstrates the Zambia River Authority’s efforts to proactively enhance the safety of the dam and ensure that it continues to perform according to its intended purpose.
He however observed that the proposed remedial and plunge pool enlargement works and modernisation of the monitoring equipment need to be implemented in the shortest possible time to guarantee continued dam safety.
“The recommendations follow very serious and alarming concern raised by the media about the state of the Kariba dam. The EIZ constituted a team of experts to undertake investigations on the state of the Kariba dam and give recommendations,” Mr Sitali said.
He added, “The plunge pool scouring has reached depths of the order of 80M and if not addressed can lead to undermining of the dam wall foundation and instability of the wall.”
Mr Sitali said the present spill way gates do not allow emergency operation in cases when the downstream gates fail to close due to deformities over the years.
“The effects of Alkali Aggregate Reaction (AAR) are volumetric expansion of the concrete leading to deformation in the spillway gate built-in parts leading to gate operation problem.”
Mr Sitali recommended that large concrete structures while operating safely are characterized by cracks of one form or the other adding that the cracks on the Kariba Dam are due to shrinkage of concrete and temperate effects over the years.
He said currently there is no possibility of closing the sluice gates under flow conditions should there be need saying this has been proposed to install an emergency spillway gate and a new gantry.
Mr Sitali also observed that most of the research on the Kariba dam has been conducted by external institutions without the participation of local researchers.
“It is therefore highly recommended that the two nations (Zambia and Zimbabwe) consider funding research using local institutions.”