Electricity + Control January 2016

A SENSE OF AFRICA

Preventing Kariba Dam catastrophe Most of the funding has been secured for the massive engineering project required to secure and rehabilitate Kariba Dam. But in De- cember 2014 the critical period was defined as ‘the next three years’, while the rehabilitation project is only due for completion in 2025. Project delay from any cause, along with climate change, high rainfall patterns impacting future dam levels and potential seismic activity, could all contribute to the likelihood of failure of the Kariba Dam. The implications of the failure of Kariba Dam were released in a report in September 2015. The ‘Impact of the failure of the Kariba Dam’ was sponsored by Aon South Africa and researched and writ- ten by Kay Darbourn of IRMSA. It tells a story around the risks and challenges for the region related to the current state of the dam and the proposed rehabilitation project. Region’s devastation If the Kariba Dam fails, the water flow fromKariba will continue down the Zambezi River, impacting people, property, animals and plant life until it reaches the Cahora Bassa Dam, at which stage the flow will cause this dam to be breeched and the cycle of damage will continue downstream.The reduction in the supply of electricity to various coun- tries in the region will be significant and immediate.This will just be the start of years of economic, social, environmental, humanitarian and technological fallout that will devastate the region’s economies. Economic impact Some countries rely mainly on hydropower from the Zambezi and their economies will be seriously impacted, both for industries that rely on electricity to operate and in terms of revenue generated from the sale of electricity. South Africa, already in a precarious energy supply shortage, will lose 1 500 MW of imported power as the Ca- hora Bassa Dam fails. Access to water for people in the Kariba and Cahora Bassa catchment areas for drinking, food and agriculture will be severely restricted.Transportation and access to the areas affected will be curtailed. New projects and investment in the region will be severely compromised, as the ongoing lack of electricity and water

Aon’s Global Risk Management Survey released earlier in 2015, and IRMSA’s first edition of the South Africa Risk Report 2015, show that the failure and shortage of critical infrastructure is amongst the top 10 SouthAfrican risks identified by business leaders and risk managers. Power supply constraints The potential failure of the Kariba Dam is a Southern Africa regional risk that would lead to severe power supply constraints – another key challenge currently impacting the region. This risk needs to be viewed as part of the existing power supply and demand challenges in the region and will require a strong commitment from governments, pri- vate companies and financiers to prevent the failure from happening. Extract from theAfrican Development Bank’s Environmen- tal and Social ImpactAssessment Summary: October 2015 The Zambezi River Authority (ZRA), a corporation jointly and equally owned by the governments of Zambia and Zimbabwe, is the project proponent for the proposed Kariba Dam Rehabilitation Works. The ZRA have initiated the Kariba Dam Rehabilitation Project, which is required to rehabilitate the plunge pool and the spill way to allow for safe operation of the dam and avoid possible catastrophic dam failure in the future. The proposed Project involves rehabilitation work to the plunge pool (anticipated to take four years to complete – i.e. 2015 to 2018) and rehabilitation of the six sluice gates (anticipated to take eight years to complete – i.e. 2015 to 2022).

Enquiries: • www.irmsa.org.za • www.aon.co.za/Publication1.aspx • www.afdb.org

will make these uneconomical, potentially for up to eight years while the dams are being rebuilt.

Electricity+Control January ‘16

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