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Poor/Glide and Riffle/Run. Deeper pool = better pool Deeper riffles & runs = better quality Diversity of current velocities available Mophology of riffles/pools affects characteristics and quality. Riffle-Pool Morphology. Current Velocities in Streams. Fast/Very Fasts. Fast. Eddy.
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Poor/Glide and Riffle/Run • Deeper pool = better pool • Deeper riffles & runs = better quality • Diversity of current velocities available • Mophology of riffles/pools affects characteristics and quality
Current Velocities in Streams Fast/Very Fasts Fast Eddy Moderate Slow
QHEI Riffle/Run Metric • If best areas < 5cm or no riffle, metric scores a zero
Riffle/Run Characteristics • What is depth of better riffle and run areas? • Measure depths in areas that are clearly run or riffle • Are substrates coarse or fine? • Are substrates in riffle/run area embedded?
Calculating Stream Gradient:“Map Gradient” • Locate site on topo map • Find upstream and downstream contour line crossings • Calculate miles between contours • E.g. 640’ – 630’/1.5 miles = 6.67’/mile
Large, Fast, Deep Riffles Low Embeddedness