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. . . adequate water quality; and . physically self-sustaining wetlands. Our research has shown that flow-through wetlands entrain the greatest number of particles and the most flow, which is advantageous for placing larvae into a productive environment and may increase their short-term survival. Thus, to maximize entrainment, flood plain wetlands should have at least one upstream breach and one downstream breach. Research performed to evaluate the Levee Removal Program demonstrated that these flow-through sites were also more efficient at transporting and entraining particulate carbon, one important component of productivity, into the flood plain (Birchell et al. 2002). High productivity, combined with potential for warmer water, should ensure that growth rates of razorback sucker larvae are fast relative to that in main channel environments (Bestgen 2008). It is difficult to ensure that nonnative predators can not infiltrate the site and reproduce. However, prior research has shown that larval razorback sucker can survive in the presence of low numbers of nonnative fishes in a year after a flood plain wetland dries (resets) because the fish community was eliminated (Modde and Haines 2005; Christopherson et al. 2004; Birchell and Christopherson 2004; Brunson and Christopherson 2005). A negative aspect of flow-through wetlands is that all suspended particles are entrained, including sediment (Heitmeyer and Fredrickson 2005). Therefore, over time, breaches as well as the associated wetland will fill and ultimately, these types of wetlands will not be sustainable without active management. For example, the natural levee at Bonanza Bridge was originally breached at a river stage of 368 m3/sec. Entrainment studies in 2006 showed that connection now occurs at a higher river stage (minimal connection at 434 m3/sec). From the high amount of scouring of sediment observed in Breach 2 in 2006, it is not difficult to hypothesize the pattern: . . . . . . . . . 50