4th workshop of the working group 2 (WGII) « Hazards and disaster

risk management in Mountains » of the Working Party on the

Management of Mountain Watersheds (WPMMW) of the European

Forestry Commission (EFC).

Terms of reference

Effect of forest and check dams on water surface,

bedload input and debris earth flow

in Alpine watersheds

Traunkirchen - Austria

Date: June 11th – 13th, 2018

Context

Following the implementation of the WGII activities and according to the workplan 2017-2018, the

WGII leaders define the terms of reference for the 4th workshop to be held during the second quarter

of 2018.

This document specifies the topic, content and program of the workshop and will be used to present

the activity to other member countries of the WPMMW to encourage them in participation to the

WGII activities.

Topic of the Workshop

The workshop aims at discussing the effect of protection forest and check dams on permanent

sediment retention. Based on a case study, participants will focus on the impact of surface runoff and

debris earthflow on the bedload input. The catchment which will serve as a study area enables an

overview on historical and recent methods in natural hazard protection and is yet to obtain a further

project including forestal measures and check dams.

Location

The workshop will take place in Austria in the Salzkammergut-region in Traunkirchen and the

Kesselbach - valley.

The site is about 90 kilometers from Salzburg Airport and about 270 kilometers from Vienna Airport

and is easily accessible by public transport.

General objective

Build and spread knowledge of practitioners on the effect of forest and check dams on torrent-

processes and the protection effect for settlements and infrastructure.

die-wildbach.at

Overview of the region (source: maps.google.at)

Specific objectives

Compare methodologies, approaches and structures implemented by the countries for the

addressed issue.

Work in groups on a solution for a specific problem that is typical for mountain watersheds in

the context of natural hazard management.

Develop a common proposal on a case study.

Program

Day 1 – Afternoon –

Welcome and Introduction

Presentation of the detailed program and

objectives of the workshop

General presentation of the region and overview

on the case study

Excursion to the Kesselbach-valley: experience

the historical techniques of sediment

management

Traunkirchen

Kesselbach - Valley

die-wildbach.at

Day 3 – Presentation and discussion of the group results

Recap of the results of each group and discussion

Overview of the group results

Elaboration of common recommendations

End of the workshop (appr. 12:30)

Attended results

A synthetic report of the workshop will be prepared by the

Austrian Service for Torrent and Avalanche Control and reviewed

by the France counterpart. It will include:

A synthesis of presentations, field visits and technical exchanges between practitioners

A synthesis of the group proposals and common recommendations

Logistics

Austria provides the organization of the workshop and a limited pick-up service from Vienna airport

and Salzburg airport. As there is one mini-bus each, an in time coordination of the flight-arrival times

will be needed. Please get in touch with Thomas Fink (mailto:Thomas.fink@bmlfuw.gv.at).

A list of accommodation will be provided to the participants. There will be one favored location, were

all participants have the possibility to stay together.

Each country will cover travel costs, accommodation and meals for its participants.

The registration to the workshop has already started. For registration please contact Thomas Fink on

behalf of the organizers thomas.fink@bmlfuw.gv.at.

The watershed of the Kesselbach

Municipality of Bad Ischl (54%) and Ebensee (46%)

Small watershed of 3,7 km²

Tributary of the Traun river

Largely forested

Mixed torrent: sediment transport and debris flows

Problematic of woody debris management during

floods

Main stakeholder: Settlement on the alluvial fan,

Austrian railways ÖBB

Day 2 - Case Study: Kesselbach

sediment management

Presentation of the

characteristics of the

“Kesselbach” catchment.

Group work in the field.

Develop a proposal on how

to bind sediments in the

catchment area with forestal

and technical measures.