Implementation projects

The implementation projects pick up on the findings from research and transfer these to practice. They bend a bow between the dangerous processes (e.g. Storms, Hail, Floods) on one hand and the damage potential as well as the vulnerability of potentially exposed objects on the other hand. It is a risk-based approach.
The implementation projects shall benefit the transfer of knowledge between research and practice (and vice versa) and are conducted in collaboration with partners from Science, Administration and Practice.

Following implementation projects are being performed:

Preparation of a spatially and time-resolved data collection of damages and inventory data as a central foundation for current and future projects.

Development of a method for the preparation of maps of the hail activity of the pervious day.

Investigation of the relationship between hail activity on the radar and damages to passenger cars.

Users report the hail observations via the MeteoSwiss app and thus offer a great added value; as a ground measuring network is missing

Development a national hazard map for hail.

Preparation of a Swiss-wide hazard map for winter storm based on data series of the last 150 years under the leadership of FOEN and MeteoSwiss.

What makes flood protection projects successful? The Mobiliar Lab for Natural Risks evaluated 71 Swiss flood control projects concerning their planning and effectivity. The aim was to gain insights into project procedure and benefits of flood protection projects and risk development.

This report evaluates the role and perspective of Swiss communes in the process of planning and implementing flood control projects. The assessment focuses on the three main aspects project procedure (project initiation, involvement of insurance companies), benefits (economic, ecologic and social) and risk (risk-based approach, risk development). Based on these three main aspects we explore what makes a successful flood control project. To answer this question, we analyzed 71 Swiss flood control projects by evaluating technical reports, online-surveys and interviews with communal project managers. Finally, the communes' perspectives were contrasted with the positions of other important stakeholders of Swiss flood control management.

Flood control measures are mostly being planned and implemented in response to flood events. Generally, the planning of the physical flood control measures is not linked with organizational or spatial planning measures to reduce the flood risk. Tools and approaches to combine flood control with ecological-, economical- or social co-benefits are available but not fully exploited. The assessment shows that flood control measures lead to a risk reduction in the protected perimeter in the short term. However, the risk development in Switzerland (increasing population and construction activity etc.) flood risk is likely to increase in the future. In Swiss flood protection the influence of insurers and other third parties is negligible. Nevertheless, financial support of third parties for flood control measures may help to accelerate project progression.

To make a successful protection project it is important to include all stakeholders at an early stage and to enhance the exchange of information among them. Additionally, the integration of spatial (watershed management, coordination of up- and downstream land owners etc.) and secotral (urban drainage, revitalization, recreation) aspects should be promoted as it verifiably creates strong co-benefits. Furthermore, to be able to move from an event-based to a risk-based strategy, an appropriate basis is required. Thereby, insurers with their expertise related to the development of risk monitoring tools may play an important role to secure the envisaged security level of flood protection in the long run.

 

Test phase with several hundred users in summer 2015.

Hagelforschung

Needs of the population to app-based weather warnings and behovioral tips as a basis for optimizing the communication of storm warnings.

In Switzerland, flood events are causing damages running into the millions. Thanks to hazard risk maps, it is known where floods can occur. Yet, how many buildings are located in flood risk areas, what’s their value, and how many people live in these buildings? The Mobiliar Lab for Natural Risks of the University of Bern has addressed these questions and developed the website www.hochwasserrisiko.ch: it shows based on the hazard risk maps, the populations potentially at risk or buildings and building values per community, district and canton.

Throughout Switzerland 270’000 buildings with a total reinstatement value of 480 billion Swiss francs are located in flood risk areas, inhabited by about 1.1 million people. Looking at the percentage of affected people or buildings by the total population or building stock, the Alpine arch (e.g. Valais, Nidwalden and “St. Gallen Rheintal”) is highly threatened. If focusing on the number of threatened people and buildings, the Central of Switzerland and the cities (especially Zurich, but also St. Gallen, Biel or Lucerne) stand out. The most affected areas – in terms of percentage and number of threatened people and buildings – are the Rhône Valley (VS), the Interlaken region, the region surrounding the Lake Lucerne, the “Linthebene“ (GL, SG, SZ) and the “St. Galler Rheintal”.

„Monitoring flood risk in Switzerland“ is a research project by the Mobiliar Lab for Natural Risks and the Federal Office for Environment of Switzerland FOEN. The project aims at connecting science and practice and is funded by both participating institutions.

The ongoing pre study provides a “state of the art” concerning monitoring of flood risk in science and in political context likewise. Focus of the study is the gathering of existing knowledge, as well as (not yet) implemented instruments and methods regarding flood risk monitoring. Based on the findings of this pre study, research questions, aims and methods of the following main project will be further specified.

Large woody material transported by rivers during floods can be jammed in naturally or artificially narrowed stream sections. This often leads to a dramatically increase of the destructive power of the flood and can cause severe damages and high costs. It is important to consider these processes in risk managements, especially with regard to extreme events like the flood in August 2005 during which more than 110’000m3 of woody material was recruited and transported in rivers. In Berne alone, a clogging of the Mattenschwelle led to backwater effects and to inundations of the Matte district with damages of over 50 Mio. CHF (Bezzola & Hegg 2007).

Figure 1: Clogging at the Mattenschwelle and inundation of the Matte district during the 2005 event. Photos: srf.ch, blick.ch

Since direct observation of these processes are difficult and rare, numeric modelling is a promising alternative. The here presented model “LWDsimR” is an adaption of the model of Mazzorana et. al. (2011) and enables a vector based and object-oriented simulation of the woody debris dynamics during floods on the basis of irregular meshes and hydrodynamic 2D inundation models. Mobilization, transport, deposition and entrapment of the woody material can be modeled with temporal and spatial high resolution. This allows the identification of possible recruitment areas, transport pathways, deposition areas and critical stream configuration for log jams as well as an estimation of the expected volume of the woody material.

Figure 2: Spatial and temporal distribution of the simulated woody debris dynamics in Uttigen (left) and the Zulg in Steffisburg (right). Basic map data: swisstopo Reproduced by permission of swisstopo (BA17018)

The model code is open source and can be downloaded on Zenodo (including istructions) or using the direct link (only Zip file). It is based on the R programming language. Scripts for preprocessing and postprocessing of the data as well as example data are available.

For detailed information about the model set up and application see the User Manual (PDF, 1.0 MB). For a detailed description of the transport equations and further information please see Mazzorana et al. (2011). For the vector based version in R please refer to Galatioto (2016).

References:

Bezzola, G. R. & Hegg, C. (2007): Ereignisanalyse Hochwasser 2005, Teil 1 – Prozesse, Schäden und erste Einordnung. Bundesamt für Umwelt BAFU, Eidgenössische Forschungsanstalt WSL. Umwelt-Wissen Nr. 0707. 215 S.

Galatioto, N. (2016): Modellierung der Schwemmholzdynamik hochwasserführender Fliessgewässer. Masterarbeit. Geographisches Institut, Universität Bern.

Mazzorana, B., Hübl, J., Zischg, A. P. & Largiader, A. (2011): Modelling woody material transport and deposition in alpine rivers. In: Natural Hazards, 56, 2: 425–449.