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. Stewart Lake, 2006 Stewart Lake, which had an open outlet throughout the 2006 sampling period and thus, was a flow-through site the entire sampling time, began filling from the outlet when flows reached about 227 m3/sec. This occurred because the outlet was at a sufficiently lower elevation than the inlet and water flowed into the downstream "outlet." Partial filling likely occurred as early as mid-April when Green River flows began increasing. Even though the flood plain was connected with the river at this flow, very little flow was passing through the inlet breach until river stage increased. Therefore, sampling did not begin until flows rose to over 322 m3/sec (includes flows from Brush Creek) on 17 May. Four sampling occasions were conducted at Stewart Lake in 2006, all on the ascending limb of the hydro graph. The percentage of flow and beads entrained increased as river stage increased, particularly as river stage increased above 424 m3/sec (Figure 17). The percentage of beads entrained increased as flows increased, which again suggested that entrainment will increase with higher river flows at Stewart Lake (Table 11). The pattern of entrainment relationships was consistent whether only top channel net samples were used, or if both top and the bottom bead density corrected samples were used; only the magnitude of bead density entrainment differed. Similar to Thunder Ranch, total bead entrainment and percent bead entrainment at Stewart Lake were highest at the highest flows. Interestingly, total beads entrained per flow entrained and total beads entrained per flow in the river were highest at the third sampling occasion (not at the peak). This is similar to Thunder Ranch in 2005, which, before the peak, also showed a higher total bead entrainment per flow entrained though not a higher bead entrainment per amount of flow in the river. . . . . . . . . . 47 .