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IV.B.l.b. Sediment augmentation Management Action: Sediment is mechanically placed into the river from banks, islands and out-of-bank areas at a rate that will eliminate the sediment deficiency and restore a balanced sediment budget within the expected future flow regime. Starting in Year 1 of the Program, choose one location on Program lands, or Cooperator lands above Overton, as this would focus sand augmentation in upstream locations which may also provide benefits for later restoration efforts downstream. River sand will be moved from approximately 20 acres and be pushed to locations and elevations where it can be mobilized by the river flow. Leveled areas would need to be lowered to the elevation that can be overtopped and scoured by a flow to prevent seedling survival. At the time of or prior to full implementation of the annual high flows in the water plan, sediment augmentation at one or more additional sites would be implemented with volumes of sand augmentation based on the estimated sediment deficiency. The rate of augmentation at each site should be guided by sediment transport rates and flows, and by monitoring at, upstream and downstream of the augmentation site. The location for these sites should be guided by the location of sediment deficiencies as determined by available data, and numerical modeling, and guided by the availability of Program lands or Cooperator lands. In addition to sand augmentation, alternative methods above will be investigated, such as channel plan form changes, improvement to tributary delivery or flow routing changes and then develop a master plan for sustaining a sediment balance over the long-term. Potential Effects: Sand augmentation, combined with flows and mechanical actions, will have the same effects as described in Section IV.B.I.a. IV.B.l.c. Flows Management Action: Using the Environmental Account in Lake McConaughy and the Program's ability to deliver 5,000 cfs of Program water at Overton, as well as the flexibility in the CNPPID and NPPD canal and reservoir system operations (assuming mutually acceptable arrangement can be made for the use of that flexibility), short-duration near-bankfull flows will be generated in the habitat reach in the springtime or at other times outside of the main irrigation season. The intent is to achieve these flows, if possible, on an annual or near-annual basis. Testing will begin in the first year of the Program with a pulse flow target of up to 5,000 cfs for three days at Overton. An "operational plan" for achieving this objective will be developed by the EA Committee, with close coordination with the ED, and implemented within the first year of the Program. This pulse flow will be monitored to test the logistics of coordinating pulse flow creation, to evaluate the effects on infrastructure, and to assess the fate and effect of the pulse as it moves to and through the habitat reach. Biologic and geomorphic monitoring and research efforts will be developed through coordination with the TAC. As the Program develops an increased ability to safely deliver pulse flow water over time, including the recovery of some lost conveyance capacity in the North Platte River at North Platte, flows of larger magnitude and/or modified durations will be generated, with increasing emphasis on achieving measurable improvements in channel morphology and habitat conditions, including increased sand bar height and reduced vegetation in the active channel. September 1, 2006 Aclaptive Management Plan 24