Next step
A. Overview
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The objective is to use natural scouring from stream flow at in-stream structures to improve pocket refuge.
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Materials for actions would be in-stream or streamside rocks and wood.
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Tools for the actions would be portable (shovels, picks, saws) for working at a stream without needing road access.
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Pockets refer to locations of more volume per unit length than elsewhere in the stream.
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They would be available to trout for refuge during periods of dewatering.
Opportunity to improve refuge by strengthening one structure and adding another
B. Reading the stream
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This next step is “reading the stream” for locations to take actions for improving pocket refuge.
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Locations where actions would cause little or no backup of water are preferred so flow would be unimpeded.
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That would mean where there is little or no adjacent flood plain for water to spread upstream of a structure.
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Locations where flow velocity is naturally higher would be preferred for the opportunity to increase it.
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This would be where streambed gradients are greater and channel widths are narrower.
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Actions would be taken to deepen and lengthen some naturally occurring pockets.
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As well, actions to create new pockets would be away from existing ones.
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That would improve refuge by distributing it along a stream.
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Locations where stream-side shade can be used would minimize heating from direct solar radiation.