Wasserbau Projekt Glyssibach and Trachtbach (Torrent Control project; several contracts)

Client: Municipality of Brienz and Canton of Bern

Location: Brienz, Berner Oberland, Switzerland

Duration: August 2005 – September 2017. Read inauguration blog post (German)

Assignment: 1 Project coordinator, DRR expert, 1 social scientist, and 1 geologist, mapping specialist

Duties and tasks
Services provided by NDR Consulting GmbH within the consortium were:

  • Documentation and analysis of disasters
  • Hazard and risk mapping for three rivers
  • Development of structural and non-structural protection concepts; cost-benefit
    analysis of structural protection works
  • Training of local intervention units
  • Development of monitoring system for landslide
  • Policy dialogue within town officials (level of safety) and awareness building of
    local inhabitants

Project Description

Extraordinary debris flows occurred in the Glyssibach and the Trachtbach in August 2005, causing damage of the order of CHF 60 M, killing 2 persons.

The works included a thorough documentation and analysis of the destructive events. An integrated safety concept included structural and non-structural measures, including hazard mapping for all rivers affecting the area. Non-structural measures: danger zones in the 2 threatened town districts with restrictions for development; flood-proofing of individual houses; monitoring, warning and evacuation concept. Structural measures: debris flow deviation, discharge corridors, accumulation basins.


  • Documentation of events and protection concept (LLE; Lokale Lösungsorientierte
    Ereignisanalys, local, solution-oriented event analysis)
  • Hazard map for Brienz and Schwanden municipalities
  • Protection concept for Brienz town and Schwanden

Partners: Consortium of firms with individual contracts: NIPO AG Utznach; Mätzener+Wyss AG Interlaken; Geo7 AG Bern

Deviation in the upstream section; discharge corridor in the downstream section