Dynamic River Management: Targets and consequences

1. Thinktank River Engineering TUD
Dynamic River Management
Targets and consequences
June 24 2002
1

2. 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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3. :
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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4. Floodplain of Rhine River near Karlsruhe
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5. Restoring small stream the “Sandbach” near Iffezheim
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6. 6

7. Also in the Dutch river “Geul”
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8. 8

9. Increasing flow conveyance :
The Gameren floodplain
June 2000
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10. Upstream view
South and East channels
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11. Downstream view
South and West channels
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12. Secondary channels and morphology
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13. 13

14. 14

15. 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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16. 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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17. Multibeam image of armoured layer
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18. Multibeam image of ds. end of armoured layer
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19. Relation between vegetation and
hydraulic roughness
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20. wilgenstruweel
20
18
[m1/2/s] 16
14
Resistance of willows 12
Chézy coëfficiënt
10
8
6
4
2
0
0 1 2 3 4 5 6 7 8
waterdepth [m]

21. Origin of hydraulic roughness
Vegetation type roughness
h
roughness
Av

22. LANDSAT
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23. Remote sensing voorbeelden: CASI
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24. detail
bushes
Height with
help of
Laseraltimetry
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25. Laseraltimetrie
•NAP – hoogte (± 5 cm)
•RD – coördinaten (± 2 cm)
•Intensiteit
•Minimaal 4 metingen/m2
inleiding weerstand lopend onderzoek hoe verder

26. 3D image
inleiding weerstand lopend onderzoek hoe verder

27. Vegetation height Hoogte op lijn door proefgebiedje
30
25
Hoogte tov NAP
20
15
10
5
170220 170240 170260 170280 170300 170320 170340
Hoogte op lijn door proefgebiedje
30
25
hoogte tov NAP
20
15
10
5
170220 170240 170260 170280 170300 170320 170340
inleiding weerstand lopend onderzoek hoe verder 27

28. Roughness map
Duursche Waarden ’97
inleiding weerstand lopend onderzoek hoe verder

29. 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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30. That’s all !
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