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<br />An experimental effort to improve connection was conducted in the spring of 2000 and <br />breaches were cut on the upstream ends of the Above Brennan and Bonanza Bridge sites. <br />Breaches configured in this manner should maximize larval razorback entrainment because water <br />flowing into the site is not dependent on "filling surges". Instead, water will flow into these sites <br />constantly during the period river flows exceed the flood ability level of the upstream breaches. <br />Evaluating the effectiveness of these new levee breach configurations will provide answers to <br />several important questions pertaining to the flood plain restoration program. These are: I) Can <br />we entrain larval razorback suckers in the flood plain by lowering levees to improve the riverine- <br />flood plain connection? 2) Can they be entrained at high enough numbers to ensure some <br />survival from predation by nonnative fish and piscivorous insects? And how should future levee <br />breaches be configured? To evaluate the entrainment effectiveness of the new upstream <br />breaches, the strategy is to monitor the passage of drifting larvae into the sites and estimate the <br />number of larvae entrained. Then, assuming some larvae are entrained, determine if any survi ve <br />within the sites. <br /> <br />Study Goal <br /> <br />To de,termine larval fish entrainment effectiveness of upstream breach configurations. <br /> <br />Studv Obiectives <br /> <br />I. Monitor passage of drifting native sucker larvae into flood plain sites through new <br />upstream connections. <br /> <br />2. Determine an estimate for the number of larvae entrained in each site. <br /> <br />3. Determine if upstream breach connections are more effective for entraining larval <br />razorback suckers than downstream breaches. <br /> <br />4. Determine if any entrained native sucker larvae survive in the flood plain. <br /> <br />IV. Study Schedule: <br /> <br />Initial year - FY 200 I <br />Final year - FY 2004 <br /> <br />As a result oflow river flows these flood plains did not connect in 2001 or 2002, so the <br />project and funding will be carried over to FY 2003. <br /> <br />V. Relationship to RIPRAP: <br />GREEN RIVER ACTION PLAN: MAIN STEM <br />II. Restore habitat <br />II.A.3. Implement levee removal strategy at high priority sites. <br />1I.A.3.c. Evaluation <br /> <br />(-6 larval entrainment page 2 <br />