Webuild has raised the structure of the Rogun hydropower dam in Tajikistan to an elevation of 1,155m above sea level, a step that will allow the level of water in the reservoir to rise by a further 40m to 1,140m above sea level.
The higher water level will increase the volume and hydraulic head available to the two generating units already running at the site, lifting their electricity output.
Webuild is carrying out Lot 2 of the scheme, which is valued at approximately $2.3bn, for OJSC Rogun HPP.
The dam is being built on the Vakhsh River and is designed to reach a final height of 335m, which the company says will make it the tallest in the world. The structure currently stands at 190m.
Once complete, the plant is to house six turbines of 600MW each, for a total installed capacity of 3.6GW, which would double Tajikistan's electricity generation capacity.
The company reports that work is on schedule across several fronts, including raising the embankment, consolidating the foundations, building grouting galleries and installing the impermeable curtain system.
Around 49 million cubic metres of material have been placed so far, more than half the planned total while over 500,000 linear metres of drilling have been completed for foundation consolidation and the grout curtain.
The project uses a phased approach under which power is produced while construction continues.
An early generation phase has been completed with the activation of the first two units.
In the initial stages, the Vakhsh was diverted through two underground tunnels to keep the dam's foundations dry, work that could only be carried out during the winter months when river levels were lower.
Financing comes from the World Bank, Cassa Depositi e Prestiti and other international financial institutions.
Webuild says the additional output could support electricity exports to neighbouring countries, including Afghanistan, Kyrgyzstan and Pakistan, and help reduce winter power shortages.
Tajikistan President Emomali Rahmon recently visited the site with Prime Minister Qohir Rasulzoda, government officials and representatives of the client.
Webuild's record includes 320 dams and hydropower plants, among them the Grand Ethiopian Renaissance Dam.
Earlier this month, Webuild signed a €2.7bn ($3.1bn) contract to deliver the Pape Tunnel and Underground Stations (PTUS) package, marking a new phase in the construction of Toronto’s Ontario Line.
