Italian construction firm Salini Impregilo has announced the start of $450m tunnel work in Buenos Aires, Argentina.
The project forms part of the Argentinean government’s public works project valued at $1.2bn to clean up the Matanza-Riachuelo Basin.
The 12km tunnel is being constructed by the consortium led by Salini Impregilo, which will flush the waste water that will be treated at one of two plants to be built near the River Plate.
The tunnel is touted to be one of the longest of its kind in the world, excavated 40m below the riverbed.
The last 1.5km of its length will be equipped with a series of steel tubes that will rise up to the riverbed. Work is anticipated to be completed by 2021.
The overall project is aimed at cleaning the basin, including drilling of dozens of kilometres of sewers and tunnels. It includes the construction of two treatment plants for sludge and water.
Inter-American Development Bank, a division of the World Bank, has provided partial funding for the project.