Name and Location
Kariba dam rehabilitation project, Zambia.

Client
Zambezi River Authority (ZRA).

Project Description
After 50 years of serving the Southern Africa region, the Kariba dam requires a series of rehabilitation works for its continued safe operation.

Failure to invest in the timely rehabilitation of the dam will result in the gradual degradation of key safety features associated with the structure to a level that is not acceptable in accordance with international standards.

These works include:
• the design, fabrication and installation of an emergency gate and a new gantry to prevent the uncontrolled loss of water in the event of floodgate failure, which will result in water levels dropping to below the minimum operating levels and interrupting power production;
• the refurbishment of the upstream stop-beam guides and the replacement of secondary concrete to prevent failure during the operation of stop-beams; and
• the reshaping of the plunge pool downstream of the dam to limit scouring and erosion that could potentially undermine the dam foundations, leading to dam failure.
The Kariba dam is one of the world’s largest hydro dams, generating more than 1 300 MW of hydropower. The dam’s wall, which is 128 m high, straddles Zambia and Zimbabwe. Should it collapse, flooding from the Zambezi river could affect parts of Zambia, Zimbabwe, Malawi and Mozambique, affecting millions of people.

Value
The cost of the Kariba dam rehabilitation is estimated at $200-million, based on a series of feasibility and design studies completed in July 2012 by consultants appointed by the Zambezi River Authority.

Duration
The Kariba dam faces collapse if not repaired in three years.

Latest Developments
The World Bank, the European Union (EU), the African Development Bank (AfDB) and the government of Sweden have agreed to provide Zimbabwe and Zambia with $294-million for the repair of structural deformations on the Kariba dam wall and avert the possible collapse of the giant hydropower station, which supplies power to both countries.

The four international financing partners and the Finance Ministers of Zambia and Zimbabwe met in Harare in February this year to sign a deal that paves the way for the start of the decade-long wall rehabilitation and repair work during the first half of 2016.

EU ambassador to Zimbabwe Phillipe van Damme said the bloc decided to provide the funding because of the potentially grave humanitarian and economic costs the region could face, should the Kariba dam wall collapse.

The EU will provide $100-million, while the World Bank and the AfDB will provide $75- million each. The remainder will come from the Swedish government, which has plegded a grant of $25-million.
Some of the money will be directed to Zambia, which will on-lend it to the ZRA.

Zambian Finance Minister Alexander Chikwanda has said that the Kariba dam wall should never collapse, as this will cause a catastrophic humanitarian disaster on communities and economic infrastructure downstream.

The Minsiter has said that any postcollapse reconstruction of the dam – which is 617 m long and holds up to 181-million cubic metres of water – will cost each of the countries more than $5-billion, which neither can afford.

Zimbabwe Energy and Power Development Ministry permanent secretary Partson Mbiriri has said that rehabilitation on the dam will start in the first half of 2016.

ZRA chairperson Charity Mwansa has said that the reshaping of the plunge pool will take three years, while the rehabilitation of the spillway gates is scheduled to take six years, with minimal disruptions to normal operations.

Key Contracts and Suppliers
AfDB (loan finance).

On Budget and on Time?
Not stated.

Contact Details for Project Information
Zambezi River Authority, tel +260 1 228401, fax +260 1 227498 or email zaraho@coppernet.zm.
AfDB senior power engineer Elizabeth Muguti, email e.muguti@afdb.org.