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<br />. <br /> <br />sand and gravel over the largely immobile cobble and boulder bed), Sediment transport at this <br />cross section was initially higher, but peaked at 413 gls on 13 May, well before the discharge peak <br />on 3 June, The downstream sampling cross section has 12 upstream pools and began with an <br />initially finer mobile-sediment distribution. Sediment transport at this cross section peaked at 452 <br />gis, simultaneously with discharge peak on 3 June. The upstream sampling cross section <br />effectively became supply-limited after 13 May, whereas the downstream cross section may not <br />yet have reached this condition, although bedload transport was lower for equivalent discharge on <br />the falling than on the rising limb. <br /> <br />Summa!)' <br /> <br />Our observations along the North Fork Poudre River following the release of sediment from <br />Halligan Reservoir suggest that magnitude, duration, and sequence of flows are all important <br />controls on bedload transport and channel recovery, As bedload moves downstream it will be at <br />least temporarily stored along pool margins and in the lee of clasts protruding from the bed of <br />riffles, Discharge magnitude will govern the volume and grain-size distribution of bedload as long <br />as the channel remains transport-limited, Flow duration will also govern bedload volume under <br />these conditions, The sequence of flows may govern bedload volume as sediment temporarily <br />stored along pool margins during high flows moves into the pool thalweg during lower flows, <br />where it can be re-entrained during subsequent higher discharges. Pool volume, which controls <br />overwinter habitat for fish, will not be substantially restored to pre-sedimentation conditions until <br />upstream pools, which function as sediment storage sites, are also substantially scoured. Fine <br />sediments will also not be flushed from pool tail and riffle spawning gravels until upstream <br />sediment storage sites are largely depleted, These conditions are now present along the study <br />portion of the North Fork Poudre River, where more than 50% of the original (pre-September <br />1996) pool volume has been recovered, <br /> <br />, <br />