120511iasi dynamic river management hendrik havinga
DESCRIPTION
Dynamic River Management: Targets and consequencesTRANSCRIPT
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Dynamic River ManagementTargets and consequences
Thinktank River Engineering TUD
June 24 2002
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Definition of Dynamic Rivermanagement (DRM)• Dynamic Rivermanagement :
River lay-out and management for functions
flood protection and navigation should offer
conditions for recovery of hydro-morphological
resilience:
System can return to original equilibrium: thus
attenuation of floodwaves, higher low water stages,
halt to bed degradation
Nature values are automatically restored !
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:Dynamic River Management: Counteracting negative effects of regulation measures
- General: small-scale measures without distant
respons (in x and t), so flexibel and reversible
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Floodplain of Rhine River near Karlsruhe
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Restoring small stream the “Sandbach” near Iffezheim
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Also in the Dutch river “Geul”
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Increasing flow conveyance :The Gameren floodplain
June 2000
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Upstream viewSouth and East channels
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Downstream viewSouth and West channels
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Secondary channels and morphology
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Consequences of “repair” measures
• Abundant vegetation in the floodplains, dynamic changes
• correction measures have to be carried out at irregular times.
• River management has to be able to track the (dynamic)
changes in the river system, forecasts the impact on different
user-interests, formulate strategies to cope with the changes
and finally (if needed) to execute short-term measures.
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Dynamic Rivermanagement System
• Elements are various quick-scan monitoring systems:
- multi-beam sounding methods
- laser-altimetry for changes in topography and vegetation patterns
- radar-reflection of waterlevels to detect changes in waterdepth (and bedlevels)
- satelite imaging
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Multibeam image of armoured layer
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Multibeam image of ds. end of armoured layer
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Relation between vegetation and hydraulic roughness
Resistance of willows
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2
4
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0 1 2 3 4 5 6 7 8waterdepth [m]
Ché
zy c
oëffi
ciën
t
[m1/
2 /s]
wilgenstruweel
Origin of hydraulic roughness
h
Av
Vegetation type
roughness
roughness
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LANDSAT
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Remote sensing voorbeelden: CASI
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detail bushes
Height with help of
Laseraltimetry
Laseraltimetrie
•NAP – hoogte (± 5 cm)•RD – coördinaten (± 2 cm)•Intensiteit•Minimaal 4 metingen/m2
inleiding weerstand lopend onderzoek hoe verder
3D image
inleiding weerstand lopend onderzoek hoe verder
27inleiding weerstand lopend onderzoek hoe verder
Hoogte op lijn door proefgebiedje
5
10
15
20
25
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170220 170240 170260 170280 170300 170320 170340
Hoo
gte
tov
NA
P
Hoogte op lijn door proefgebiedje
5
10
15
20
25
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170220 170240 170260 170280 170300 170320 170340
hoog
te t
ov N
AP
Vegetation height
Roughness mapDuursche Waarden ’97
inleiding weerstand lopend onderzoek hoe verder
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DRM: Consequences for day to day management
• Dealing with uncertainties
– more morpho-dynamics
– more interaction with terrain-owners
• Organisational modifications
• Introduction and implementation of high-tech monitoring
systems and DSS
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That’s all !