Beautiful blue skies in southern France on Friday for SUBTERRA’s successful installation of a DN300 HDD gas pipeline under the Garonne River, the second of 2 parallel 364-metre-long crossings. Crossing the Garonne was another important step in Teréga’s network renewal programme, which followed the 607-metre-long DN150 / DN300 parallel crossing under the Ariège River a few weeks ago.
With a 60-metre height difference between the entry and exit points on the Ariège crossing, the job was far from straightforward. The complex geology of both sites, with significant gravel layers and in flood risk areas, required careful monitoring and casing to enhance pipe stability.
OPTIMUM trenchless specialists accompanied SUBTERRA during the engineering design phase and throughout the drilling works of both crossings, determining casing characteristics and analysing drilling parameters.
Congratulations to everyone involved ; great teamwork !
