Launch of works to clean up Buenos Aires rivers 10 Aug 2017

TBM components lowered for assembly

President Mauricio Macri launches preparatory works

Preparatory work has started on the water tunnel to clean up the Matanza-Riachuelo Basin in Buenos Aires, one of the most polluted rivers in the world. To be built by Salini Impregilo, the US$450 million tunnel system is part of the biggest public works project undertaken by the Argentine government, valued at $1.2 billion.

The tunnel will be built by a double shield TBM and lined with reinforced concrete and will take away the wastewater that has been treated at one of two plants. At 12km, the tunnel will 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 puncture the bottom of the river bed, allowing the treated water to exit. With a hydraulic diameter ranging between 1.7m to 3.8m i.d. the tunnel will be able to carry this water at a flow rate of 27m³ per second.

“This is a great day,” said Argentine President Maurcio Macri as he presided over the lowering of the TBM head down the shaft where drilling will start. “It fills me with hope and is one of the most important projects being financed by the World Bank today.”

The Matanza-Riachuelo Basin is home to 23% of the residents of metropolitan Buenos Aires and 9.16% of the total population of Argentina who stand to benefit from the project at the health and environmental level. Work is expected to finish by 2021.