Post on 27-Jul-2022
Natural Hazards and Risk Analysis in Mountain Regions,
‘Blockkurs’ GEO 805
Field part, Lauterbrunnen, 4-6 September, 2019
Christian Huggel, UZH
Brian McArdell, WSL
Demian Schneider, Tiefbauamt, Kanton Bern
Randy Muñoz, UZH
Hazard and Risk Analysis Course, Lauterbrunnen
Keystone / VBS / sda / Blick
Cengalo/Bondo events 2017
Hazard and Risk Analysis Course, Lauterbrunnen
Lin Nyunt / The Telegraph
Hazard and Risk Analysis Course, Lauterbrunnen
20Minuten
July 2019
Debris flow from subglacial drainage, Triftbach, Zermatt
Hazard and Risk Analysis Course, Lauterbrunnen
Learn, collect experiences
Hazard and Risk Analysis Course, Lauterbrunnen
Informed and critical thinking and assessment
Hazard and Risk Analysis Course, Lauterbrunnen
Recognize problems and uncertainties
Hazard and Risk Analysis Course, Lauterbrunnen
Orders of magnitude, no fine tuning
Hazard and Risk Analysis Course, Lauterbrunnen
Estimate, generalize, leave out
Hazard and Risk Analysis Course, Lauterbrunnen
Working under pressure
Hazard and Risk Analysis Course, Lauterbrunnen
Time management
Hazard and Risk Analysis Course, Lauterbrunnen
Improvisation
Hazard and Risk Analysis Course, Lauterbrunnen
FUN !
Hazard and Risk Analysis Course, Lauterbrunnen
• There is not THE solution
• Collect experiences, feedback is important
• We support you but you decide
Hazard and Risk Analysis Course, Lauterbrunnen
Learning objectives:
After this course you should be able to:
… understand and correctly apply the terminologies related to hazards,
vulnerability, damage potential and risk.
… perform a hazard assessment and hazard mapping of debris flows and
floods in mountain areas.
… distinguish a variety of vulnerability-categories and perform the
according data acquisition and mapping.
… realize a simple risk assessment and -mapping on the basis of the
hazard- and vulnerability/damage potential-mapping.
… analyze hazards, vulnerability/damage potential and risk for a given
case study appropriately and derive according recommendations for
stakeholders.
Hazard and Risk Analysis Course, Lauterbrunnen
Study area and processes: limitations
Hazard and Risk Analysis Course, Lauterbrunnen
Concentration on debris flows (torrents) and floods
Rock fall, landslides, avalanches are not considered
Hazard and Risk Analysis Course, Lauterbrunnen
Study area Lauterbrunnen
Rybibach
Mättlibach
Gryfenbach
Fluebächli
Louwibach
Weisse Lütschine
Hazard and Risk Analysis Course, Lauterbrunnen
Hazard and Risk Analysis Course, Lauterbrunnen
Hazard and Risk Analysis Course, Lauterbrunnen
Hazard and Risk Analysis Course, Lauterbrunnen
2009
Hazard and Risk Analysis Course, Lauterbrunnen
2012
Hazard and Risk Analysis Course, Lauterbrunnen
2013
Hazard and Risk Analysis Course, Lauterbrunnen
Hazard and Risk Analysis Course, Lauterbrunnen
Hazard and Risk Analysis Course, Lauterbrunnen
Louibach
Hazard and Risk Analysis Course, Lauterbrunnen
Spiessbach
Hazard and Risk Analysis Course, Lauterbrunnen
Spiessbach
Hazard and Risk Analysis Course, Lauterbrunnen
Flood process
Hazard and Risk Analysis Course, Lauterbrunnen
2005 floods in Switzerland
Bern Entlebuch
Processes
Hazard and Risk Analysis Course, Lauterbrunnen
Processes
Damming and lateral overflow
Klosters - 2005 Schattdorf - 2005
Emmental – Kemmeribodenbad - 2014
N. Wächter
Hazard and Risk Analysis Course, Lauterbrunnen
Processes
Lateral overflow
N. Wächter
Engelberger Aa 2005
Planat.ch
Hazard and Risk Analysis Course, Lauterbrunnen
Processes
Blocking at structural
barriers such as bridges.
Damming and lateral
overflow
Thun
Emmental 2014
20 minuten
Hazard and Risk Analysis Course, Lauterbrunnen
Lateral undercuttingEngelberg
Sediment transport and deposition
Processes
Hazard and Risk Analysis Course, Lauterbrunnen
Undercutting
Río Vilcanota, Aguascalientes (Machu Picchu, Peru), Jan. 2010
Processes
Hazard and Risk Analysis Course, Lauterbrunnen
Transformation into
torrent and debris flow processes
Lütschinental
Processes
Hazard and Risk Analysis Course, Lauterbrunnen
Unchannelized (hillslope) debris flows
Processes
Hazard and Risk Analysis Course, Lauterbrunnen
Catchment
• Precipitation intensity and
duration
• Characteristics of soil and
surface (glacier, bedrock,
vegetation etc)
• Catchment size
• Topography
• etc
Lauterbrunnen
Runoff coefficient
Processes: runoff generation
Hazard and Risk Analysis Course, Lauterbrunnen
Processes: Precipitation
Meteoswiss precipitation radar
Hazard and Risk Analysis Course, Lauterbrunnen
Processes: Precipitation
Precipitation radar in the Andes of Peru
U Stuttgart / UZH / UNASAM
Hazard and Risk Analysis Course, Lauterbrunnen
Runoff response depending on rainfall and catchment characteristics
Runoff response
slideshare.net
Hazard and Risk Analysis Course, Lauterbrunnen
Extreme value analysis on the basis of
observed runoff measurements
BWG, 2003
Hazard and Risk Analysis Course, Lauterbrunnen
Typical return periods
(‚Jährlichkeiten‘)
• 30 yr return period flood (30-jährliches HW)
• 100 yr return period flood (100-jährliches HW)
• 300 yr return period flood (300-jährliches HW)
• Extreme flood (EHQ)
Hazard and Risk Analysis Course, Lauterbrunnen
Flood estimates in catchments without runoff measurements
• different, mainly empirical methods
• partly distinction of medium-sized (10-500 km2) and small catchments (<10km2)
e.g. Kölla (1986):
Hazard and Risk Analysis Course, Lauterbrunnen
bFnaHQ 100bFnaQ max
HQ100 100-jährliche Abflussspitze [m3/s]
Qmax maximale Abflussspitze [m3/s]
a regionenspezifischer Parameter [-] Region A1: 4,36 für HQ100 bzw. 6.03 für Qmax
b regionenspezifischer Parameter [-] Region A1: 0.64 für HQ100 und Qmax
Fn Einzugsgebietsgrösse [km2] Karte
GIUB’96
Hazard and Risk Analysis Course, Lauterbrunnen
Hazard mapping
Hazard and Risk Analysis Course, Lauterbrunnen
Prozess Low intensity Medium
intensity
High intensity
Rockfall E < 30kJ 30 < E <
300kJ
E < 300kJ
Landslide v: ≤ 2cm/Jahr v: dm/Jahr (>
2cm/Jahr)
starke
Differentialbeweg
ungen;
v > 0.1m/Tag bei
oberflächlichen
Rutschungen;
Verschiebungen >
1m pro Ereignis
Debris flow h < 1m h > 1m
Intensity - debris flow Intensity - Flood
E = kinetic energyh = Thickness of debris flow depositsv = long-term average slope deformationafter Lateltin, 1997.
Hazard and Risk Analysis Course, Lauterbrunnen
Probability Return period
Hazard and Risk Analysis Course, Lauterbrunnen
123
456
789
0
red
blue
yellow
whiteor hatched
yellow-whiteIn
te
ns
ity high
medium
low
high medium low
Probability
residualrisk
nach Raetzo et al., 2002
Gefahrenstufe Sachliche Bedeutung Raumplanerische
Bedeutung
Rot Erhebliche Gefährdung Verbotsbereich
Blau Mittlere Gefährdung Gebotsbereich
Gelb Geringe Gefährdung Hinweisbereich
Gelb-weiss Restgefährdung Hinweisbereich
Weiss Keine Gefährdung* Keine Einschränkungen*
*nach derzeitigem Wissensstand
Nach BWG, 2001
Hazard and Risk Analysis Course, Lauterbrunnen
Hazard maps are instruments of spatial planning to delimit endangered areas
and to prevent from damages.
Hazard maps often do not exactly correspond to actually occurring processes
and need to be updated.
Example
Brienz 2005
Hazard and Risk Analysis Course, Lauterbrunnen
Hazard zone limits cannot be understood as precise delimitation of processes
Example
Bondo 2017(Keystone)
Hazard and Risk Analysis Course, Lauterbrunnen
Hazard mapping in the broader land-use planning and construction processes
Guidelines Kanton
Graubünden, 2017
Hazard and Risk Analysis Course, Lauterbrunnen
The final presentation
should take 10 minutes (plus ca. 5 min discussion) and all the
treated aspects need to be involved, such as:
1. Debris flow hazards (values / map) (you can focus on 2
catchments out of 4)
2. Flood hazards (values / map)
3. Damage potential (classes / map)
4. Risk (matrix / values / map / hotspots)
5. Possible measures with a limited budget (priority list)
6. Discussion / further information
Hazard and Risk Analysis Course, Lauterbrunnen
Status of examination of the course:
Passed / not passed