Client: EDIL IDRAULICA Sas – Italy
What I did: I made the project management and the supervision of the installation, by HDD, of three HDPE DN 560 (22 in) pressure sewer pipes under the Foglia river, Pesaro, Italy. Three directional pilot bore, with an interaxis of just 1,5 m, along a drill path with a very sharp bending radius (70 m), were successfully drilled under the river bed, facing challenging soil conditions, with big boulders and blocks of stone in a matrix of silt and clay. Although the three pilot bores were perfectly completed, on the first alignment, after completed the first final reaming at 700 mm, the first pull-back failed due to the collapse of underground unstable big blocks of rock. Despite the prohibitive soil conditions we successfully completed the pullback of the two remaining product pipes, achieving a remarkable result in a very difficult HDD work.