MMtodos para la estimacitodos para la estimacin de n de sedimentossedimentos

ALPS

JURA

FLAT L

AND

Europakarte

Densidad de la Populacion Suiza Densidad de la Populacion Suiza

populacion densa Uso del suelo: conflicto entre la natura y la actividad humana

Hace pocos anos: elaboracion de mapas de riesgo

estimacion del arrastre de fondo= una herramienta importante para la elaboracion de mapas de riesgo y la planificacion del ordenamiento territorial tanto como para la planificacion y construccion de medidas de proteccion

2 metodos para la estimation del aporte de sedimentos en cuencas alpinas

Como determinar Como determinar el aporte de los el aporte de los

sedimentos?sedimentos?

Estimacin del Transporte de Sedimentos a travs de Depsitos

Estimation of sediment transport by sediment retention Estimation of sediment transport by sediment retention reservoirsreservoirs

por una red depor una red demedicionmedicion

Por la calculacion a travez de formulasPor la calculacion a travez de formulas

??

Dos metodologias para Dos metodologias para la estimacion la estimacion ..

project

development

Estimated Process

Estimated bed load

Lehmann Gertsch

PH D Thesis 1993

80 torrents, 1987-1992

Sediment transport

Bed load balancesTotal Bed load charge

Return period100 years

PH D Thesis 2009

58 events , 1987-2005

Debris flows

Bed load balancesTotal Bed load charge

Return period>100 years

Metodologia

Metodologia Lehmann

A Handbook with description of the method is available

Erosion + Transport

Accumulation ?

Retention Basin planned

Sediment yield? Scenarios?

Procedure to assess sediment yield in mountain streams

Procedimiento de la Estimacin del Aporte de Sedimentos en Torrentes

Preparations

Collect data

Study and interpret data

First evaluation of mountain stream

Collection and processing ofdischarge information

Field Work

Assign mountain stream to a category:- no debris flow stream- debris flow stream with deposits- debris flow stream without deposits

Record parameters applicable tocategory

Analysis

Calculation of sediment yield at the conefor the corresponding category

Plausibility check and sensitivityanalysis

Check results of prepartion work againstfield conditions

Assessment in the field

Alta relevancia Relevancia posibleRelevancia probable

Deslizamiento

Transporte enBarranca

Flujo de Lodo

Falla de la Escarpa

Transporteen el Ri

Fuente Fuente de erosion?de erosion?

Cual de los Cual de los procesos es procesos es relevante ?relevante ?

Calculo con formulaCalculo con formulaT

ran

spo

rtkapa

zitt

gross

klein

Bannwald

Pendiente

?? Dimensiones?

Aporte lateral: Deslizamientos

?espesor

longuitud

Ejemplos para la estimacion de los volumenes

Propuestas para cada tipo de fuente

de sedimentos

Procedure:Determination of sediment balance for each channel section

Level of operation: Handbook Theory book Computer program for calculation

Procedimiento: Determinacin de la Erosin y de la Acumulacin para cada seccin del Torrente

Herramientas para el Procedimiento: Manual Libro Especializado Programa de Computacin

Assessment of sediment yield in mountain streams

Estimacin del Aporte de Sedimentos en Torrentes

...por tramos...

Estimation of sediment transport in small mountain streamsResultado de la Estimacin del Transporte de

Sedimentos en el Torrente Guppenruns

Sediment transport during a 100-year flood in the Guppenruns

Cross section Nr.

V

o

l

u

m

e

Transport capacitySediment yield

Sediment potentialDeposits

740

760

780

800

820

840

860

880

900

920

940

0

5000

10000

15000

20000

250007

2

5

6

7

4

5

6

7

6

5

6

7

8

5

6

7

9

9

6

8

1

5

6

8

3

5

6

8

5

5

6

8

7

5

6

8

9

5

6

/

2

4 6 8

1

0

1

2

1

4

1

6

1

8

2

0

2

2

2

4

2

6

2

8

3

0

3

2

3

4

3

6

3

8

4

0

4

2

4

4

4

5

a

4

6

a

4

8

5

0

5

2

F

e

s

t

s

t

o

f

f

f

r

a

c

h

t

(

m

3

)

Nr. der Querprofile

Scenarios with a short and long rainfall input with a river bed widening

Bornige BrckeMdg. Trmmelbach

Mattebach

Sefinenltschin

untere --- obere Stechelbergbrcke

change of bed levelBornige Brcke

Mdg. Trmmelbach

Mattebach

Sefinenltschi

untere --- obere Stechelbergbrcke

Q = 83 m3/s Q = 57 m3/s

Lange Ganglinie

Metodologia Gertsch

Assessment of hillslope processes

Assessment of channel processes

Bed load balances in all channel parts in dependance from scenario

Total bed load at fan apex

Composition of data Digital data, and field data

Scenario definition qualitative, descriptive

With the aid of developped assessment matrixes for hillslopes and channel automated programme

Delineation of channel parts and adjoining slope parts

Possible with GIS

Extraction of input parameters

Combined impact of all influence factors Combined impact of all

influence factors is essential for bed load mobilisation

Every channel part is influenced by a unique and individual combination of influence-factors

Combined impact = complex

During the combined impact, the different influence-factors can: cumulate each other

compete against each other eleminate each other I

Influence-factor do not have the same weight in each situation

Understanding system element studying channel part

Channel part to be assessed

perspective

Influence factors system element-level

local disposition

Bed load supplyEdisriederbach, Sachseln

rock

Leimbach, Frutigen

limited

Milibach, Meiringen

unlimited

Local disposition

Torrent de Sax, Fully

steep erosion flat deposition

Rio de Tennasses, Chteau-dOex

Channel gradient

Local disposition

Channel part to be assessed

perspective

Interaction between system elements studying channel parts upstream

conditions upstream

Influence factors interaction-level

Runoff supply / catchment area aboveLes Creusats, Orsires

Local disposition

Channel part to be assessed

perspective

flip-over-effects in the system looking for critical constallations or processes

negative factors

special conditions or processes

release of extreme debris flows

extreme erosion rates from release point untill fan apex flip-over-effect

erosion rates > 30 m3/m

Influence factors flip-over-level

Release of debris flows in bastion-moraines Rotlauibach, Guttannen (Foto: Flotron AG)

Confluence of several channels at the same locationRotlauibach, Guttannen (Foto: Flotron AG)

Assessment criteria Decision-making support Assessment and quantification

Local disposition

Transport process

Repressing and increasing factors for

erosion

influence-factor-combination

Assessment line

Quantification

* 400m = 1600m3

* 200m = 8000m3

* 800m = 0m3

* 130m = 11700m3

Simulacion Evento 2004 (oleaje)

Total = 21000 m3

4m3/m40m3/m0m3/m

90m3/m

* 400m = 1600m3

* 200m = 2000m3

* 800m = 0m3

* 130m = 2210m3

Scenario Flujo de escombros

Total = 6000 m3

4m3/m10m3/m0m3/m

17m3/m

Scenario Bed load transport without release of debris flow

Total = 1720 m3

* 400m = 800m3

* 200m = 400m3

* 800m = 0m3

* 130m = 520m3

2m3/m2m3/m0m3/m

4m3/m

Estimated Process

Estimated bed loadReturn period

Necessary time for application for a unit of 5km2-catchment

ScaleChannel gradient

Methode Lehmann Methode Gertsch

Sediment transport

Bed load balancesTotal Bed load charge

Return period100 years

3 days

< 50 km2

> 2%

Debris flows

Bed load balancesTotal Bed load charge

Return period>100 years

2 days

< 10 km2

> 10%

Comparacion final

Gracias por su atencion!!!!!