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Fishways Their Application in Affording Fish
Passage
Washington State Department of Fish and Wildlife
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Fishway

• Any human-made structure that facilitates the
  passage of fish over, through or around a
  barrier.

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RCW 77.53.030

• A dam or other obstruction across or in a stream
  shall be provided with a durable and efficient
  fishway.
• The fishway shall be maintained in an effective
  condition and continuously supplied with
  sufficient water to freely pass fish.

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Aggrading Channel
Degrading Channel
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Design Factors

• Fish species
• Fish age class
• Fish condition
• System scale channel and hydrology
• Degree of flow control
• Operation and maintenance dependability

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Fishway Types

• Weir-Pool
• Vertical Slot
• Trap Haul
• Pool-Chute
• Streambed Controls
• Baffles Weirs
• Alaskan Steep Pass
• Rock-cuts

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Weir Pool Fishways
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Maintenance Issues
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Vertical Slot Fishways
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Trap Haul
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Pool Chute Fishways
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Streambed Controls
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Maintenance Issues
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Baffles
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Maintenance Issues
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Summary

• A fishway prescription should only be applied to
  human-made barriers when the infrastructure must
  be retained and can be adequately maintained over
  time.
• Realize that fishways have a relatively short
  stream life before requiring major
  repair/replacement.
• Fishways can only be effective if continually
  monitored and maintained.