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. . density was uniform in the portion of the water column above a horizontal line across the breach consistent with the top of the two lower nets. Entrainment rates of beads were then estimated for the volume of water carried in each of the lower and upper cells of the inlet canal. Because previous unpublished laboratory tests showed that semi-buoyant beads similar to the ones used were heavier than water at temperatures below about 180C, and because all samples were collected at water temperatures lower than that, we adjusted entrainment rates of Stewart Lake samples accordingly using the proportion of beads carried in the lower cell compared to the upper. This proportion varied at each sampling period by the amount of water carried in the upper cell relative to that in the lower. At higher flows the upper cell was a greater percentage of the total inflow; at flows lower than those observed on 18 May 2006, the percentage was lower because the thickness of the lower layer did not change for each sampling occasion. Flows in the two mid-column nets (16 and 20 cm/sec, mean = 18 cm/sec) on 18 May were on average two cm/sec faster than the two lower-column nets (14 and 18 cm/sec, mean = 16 cm/sec) so for sampling occasions other than on 18 May, lower-column cell flow rates were assumed only 89% (16 cm/sec mean velocity in the lower cell divided by 18 cm/sec in the upper cell * 100 = 89%) of that estimated from upper cell rates. The lower cell flow rates were used as the average velocity in the lower cell, and bead entrainment rates were adjusted accordingly. . . . . It . . Bonanza Bridge Bonanza Bridge was sampled on only three days (23, 25, and 27 May, Table 1) due to its higher flow connection to the river (approximately 453 m3/sec). Connection at Bonanza Bridge occurred on 22 May. However, the inflow into Breach 2 (the largest breach) was only 0.1 m3/sec so the site was not sampled until the following day when flows were higher. Red beads were . 30 .