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Tuesday
08 Apr 2025

Main Construction Work on Gigerwald Dam Renovation Completed on Schedule

08 Apr 2025  by water power   
 Axpo and Kraftwerke Sarganserland AG (KSL) have wrapped up the primary stage of the Gigerwald dam’s partial renovation in St. Gallen, Switzerland. The last concrete pour took place on Wednesday, 2 April 2025, completing the structural efforts to elevate the bottom outlet and headwater intake. With the temporary dewatering system shut off, the reservoir is now refilling.


Construction site at the Gigerwald reservoir, owned by Axpo and Kraftwerke Sarganserland, photographed on Tuesday, March 18, 2025, in Vaettis.

The project tackled silting challenges by raising key intake structures roughly 20 meters higher, ensuring the dam and the Mapragg power plant remain safe and functional. Axpo, working with Lombardi Engineering Switzerland, spent years planning the upgrade, which carries a cost of about CHF 25 million. The adjustment secures the dam’s long-term reliability.

Erich Schmid, Axpo’s project manager, noted: “Thanks to the good preparation and the great commitment of everyone involved, we were able to complete the work on schedule, according to plan and without any major incidents.” The successful execution reflects strong teamwork and careful coordination.

Work kicked off in June 2024 with site setup. The reservoir was drained in September to access the intake structure, and the main construction unfolded over the winter, a period of lower water flow that reduced production downtime. Up to 50 workers operated in two shifts, six days a week, to keep progress steady. Marti Group contributed to both preparation and construction phases.

Since late March, the Gigerwald reservoir has been refilling, a process expected to last around three weeks, depending on water inflow. The Mapragg power plant should restart by late April. Meanwhile, crews are dismantling construction equipment, and the dam crest path will reopen to visitors by the end of May.

This renovation enhances the dam’s infrastructure without altering broader economic patterns like exports or consumption. It focuses purely on operational improvements, maintaining energy production capacity in the region. The collaboration between Axpo and KSL, supported by skilled engineering and labor, ensures the facility’s continued service.

The Gigerwald dam project highlights practical engineering solutions for aging infrastructure, adapting to natural challenges like silting. With the structural phase complete, the focus shifts to restoring full operations and public access, marking a smooth transition from construction to regular use. The investment reflects a commitment to sustainable energy infrastructure in Switzerland, benefiting the local area without disrupting wider trade dynamics.

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