Matanza Riachuelo Lot 1

The Matanza Riachuelo river catchment development includes the left margin collector, the Baja Costanera collector deviation and complementary works. The project, funded by the World Bank, will benefit more than 300,000 people living in flood affected areas. The water drainage tunnel alignment will cross under the Buenos Aires port area and thus requires severe control to manage water.
An underground main line tunnel of two different diameters is being excavated. It is bored with a 3.84m diameter Earth Pressure Balanced (EPB) TBM for a length of more than 9km, and a 5.25m diameter Mix Shield TBM for other 5km, connecting the different areas. The boring machines will be operating simultaneously for most of their journey. The two 60m depth circular secant shafts for the launch of the first of the two TBMs have been completed in the first half of December 2017 with the use of a last generation hydromill.
The mainline has overall 17km of ramified tunnels excavated with two different microtunnelling machines of 1.08m and 1.40m diameter and a 530m tunnel excavated through conventional drill and blast methods. These lines will connect 20 access shafts and 11 minor shafts excavated from the surface.