Proud to have accompanied project owner RTE for the successful completion of a new microtunnel under the River Neste at the foot of the Pyrenees in southern France. The project falls within the framework of RTE’s ongoing network renewal and extension in the region.
Despite the relatively short tunnel length, the 65-metre-long, 12-metre-deep, AVN1800 microtunnel merited close monitoring, given the complex and varied geology of the area. The hard and abrasive nature of the successive alluvium, limestone, marble and granite blocks, made for challenging conditions and called for supervision by trenchless specialists.
OPTIMUM engineers began working on the project in 2018 with initial feasibility studies (G1 PGC) and design engineering (G2 PRO). They then supported RTE teams prior to the microtunnel construction by analysing and validating the trenchless engineering hypotheses. The resulting project knowledge (constraints, context, procedures) informed the supervision phase throughout, ensuring the 5-week-long tunnelling works ran as smoothly as possible.
