Case Study: Avalanche Control Authority halts a major landslide and protects homes with Trimble GNSS solutions

Stopping a Landslide in Austria Using GNSS Technology to Measure a Mass on the Move

The Austrian Service for Avalanche and Torrent Control (Wildbach und Lawinenverbauung) confronted a fast-moving landslide in the narrow Gschliefgraben valley near Gmunden that threatened homes and businesses. A mass of debris mobilized after heavy rains, moving as much as 4.7 m per day and prompting evacuation and a disaster declaration; unstable, shifting ground made traditional surveying impractical, so rapid, accurate displacement monitoring was urgently needed.

Wildbach adopted GNSS monitoring using a Trimble 5800 receiver with a TSC2 controller and real‑time corrections from Energie AG’s NetFocus RTN over cellular links, establishing roughly 150 monitoring points and measuring remaining points in under three hours. The GPS data supported airborne laser scans and guided drainage wells, ditches, pilings and earthworks that halted movement (about 3.8 million m3 of earth stopped), removed 250,000 m3 of material, allowed some reoccupation, and established ongoing monitoring (66 weekly points) as part of a broader €11M prevention program.