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METHODS <br />Initial draining of the stilling basins <br />Sampling in the outlet basin was done in 2002 and 2004. In 2002, pumping of the outlet <br />basin began on 4 March and was completed on 8 March. In 2004, pumping of the outlet basin <br />began on 15 March and was completed on 17 March. All fish were removed using a seine, <br />identified, and enumerated. A representative sample of fish was measured and weighed. <br />In 2002, pumping of the spillway basin began on 1 Z March and was terminated <br />prematurely as the reservoir began to spill on 28 March. Because of the incomplete pumping, <br />removal of all fishes was difficult. Despite not being able to remove all fish, crews were able to <br />use multiple sampling techniques (electrofishing, trammel netting, seining) to remove as many <br />fish as possible. In 2004, pumping of the spillway basin began on 18 March and was completed 7 <br />April. This was the only draining in 2004, as no spill occurred this year. In 2005, the spillway <br />basin was drained beginning 8 June and ending 14 June prior to the spill and was intensively <br />sampled to evaluate presence and relative abundance offish. <br />In order to keep fish from downstream sections of the river from moving into the <br />spillway basin, a block net weir (weir) was installed downriver from the basin. This weir was in <br />place from the beginning of the study in 2002 through the end of the study in 2005 (Figure 3). <br />The spillway basin weir was constructed using stock panels for a rigid frame overlaid with %" <br />mesh screening and was anchored to the riverbank using gabion baskets. The center of the weir <br />was also anchored to a gabion basket. The weir below the spillway basin was placed, monitored, <br />and cleaned daily during the spill period. Crews were asked by the Central Utah Water <br />Conservancy District to refrain from setting up a separate weir between the outlet basin and the <br />river in order to keep the outlet works clear for water releases. <br />6 <br />