Membrane construction aqueduct Langdeel N31

The Langdeel Aqueduct, built from 2004 to 2007, is a crucial component of the Standing Mast Route that connects the IJsselmeer with the Wadden Sea. This aqueduct has significantly reduced congestion by eliminating the crossing of the canal and the N31. One of the challenging aspects of this project was the excavation. The construction pit, approximately 800 meters long, 230 meters wide, and over 24 meters deep, remains one of the largest in the world where a geomembrane was applied “in den natte.”

The required geomembrane, covering an area of more than 120,000 square meters, was prefabricated by Genap into one complete membrane and then pulled over the wet excavation. Water was then pumped onto the geomembrane construction to sink it to the bottom of the construction pit. Subsequently, the pit was filled with sand, creating a dry working environment. The watertightness of the geomembrane construction was successfully tested by TNO. After that, the N31 was constructed in the pit, allowing the national highway to be led under the canal.