Natural Flood Defences RhineMeuse

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Natural Flood DefencesRhine/Meuse

• Wouter Helmer
• Ark Foundation

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Ark Foundationnature and landscape development

• More room for natural processes

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Ark Foundationmain principles

• More room for natural processes
• (Economic) Partnerships

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Ark Foundationmain principles

• More room for natural processes
• (Economic) Partnerships
• Local commitment

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Ark Foundationworking method

• Regional vision Local examples

Upstream Ambleve (Ardennes) Mountains of
Water Geulle (Limburg-NL)
Downstream Millingerwaard Living
Rivers (Gelderse Poort)
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Mountains of Water

• Waterretention in lower mountains (Ardennes,
• Eiffel, Schwarzwald)

• Retention in brooks (Ambleve, Ourthe, Geulle,
  Worm, Ober-Main)

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Mountains of Water

• Waterretention in lower mountains (Ardennes,
• Eiffel, Schwarzwald)

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Mountains of Water

• Waterretention in lower mountains (Ardennes,
  Eiffel, Schwarzwald)
• Meuse reduction of discharge by restoration of
  the natural sponges in brooklets Ardennes
• 3000-3500 m3/s Borgharen ca.6 reduction!

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Mountains of Water
Retention in brooks (Ambleve, Ourthe, Geulle,
Worm, Ober-Main)

• Remove campshedding
• Let falling trees deregulate stream
• Clay-layer from centuries of unnatural
  sedimentation will be removed by the brook

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Mountains of water
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Mountains of Water

• Retention in brooks (Ambleve, Ourthe, Geulle,
  Worm, Ober-Main)

1924 1975 1989
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Mountains of Water

• Retention in brooks (Ambleve, Ourthe, Geulle,
  Worm, Ober-Main)
• Meuse reduction of discharge by restoration of
  the natural floodplains of the larger brooks
• 3000-3500 m3/s Borgharen ca. 5 reduction!

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Living Rivers

• Clay excavation
• Sidechannels
• Herbivory
• Cyclic rejuvenation

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Living Rivers

• Clay-excavation

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Living Rivers
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Living Rivers

• 50.000 new houses ca.150 ha new nature

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Living Rivers

• Sidechannels

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Living rivers

• 220 km new side channels
• Compensation for natural vegetation and new
  riverdunes

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Living Rivers

• Herbivory
• Wild horses and cattle
• animal/2-4 ha yearround
• delay of forest development
• Beaver
• 4000 kg/year/beaver
• local clearcutting of riverine forests
• facilitates grazing

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Living Rivers
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Living Rivers
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Living Rivers

• 16.000 m3/s solutions within Riverforelands
• 18.000 m3/s Old Rhine/Linge-floodplain

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Living Rivers