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' Long-term: 5. Develop a mechanism to allow wild larvae and adult razorback ' sucker access to this bottomland during runoff in the spring. This could be accomplished when adult razorback sucker become established in the river and spawn upstream. 6. Provide wetland habitat for waterfowl, shorebirds, and other wildlife. ' From the contour maps, the site is relatively flat with only three identified depressions that are remnants of the former side channel (Appendix A: Photo 5). Tamarisk stands are the dominant vegetation type. The restoration ' strategy at Site 1 is to reconnect the mainstem river with the former side channel that will allow inundation during spring runoff. This proposed conceptual design should serve as an off-channel habitat for endangered fish and ' will create waterfowl nesting habitat. Initially, both water and fish control structures would be installed at the inlet and outlet to regulate water and fish access from the river. These structures would be incorporated into the existing dike. Although diking is considered detrimental to floodplain restoration, this ' dike will serve as a 'containment area' from high flows and provide lateral support for the inlet and outlet structures. Three compartments or cells would be developed in Site 1 to conduct in situ biological studies aimed at, 1) ' monitoring survival and growth of stocked post-larval and fingerling razorback sucker in the presence and absence of non-native fishes found in the Gunnison River, and 2) determining the extent and impact trace metals (selenium, boron, zinc) may have on the various life stages of razorback sucker. Initially, the ' containment area could serve as a grow-out for restoration stocking of endangered fish into the river. When needed studies are completed, the fish control structures could be removed to allow unregulated access for fish to and from the ' river. Water control structures would remain in place to control river flows into the side channel, if necessary. ' A 6-foot deep channel with an "S"-shaped configuration would be constructed from the inlet to the outlet, utilizing much of the existing depression (Figure 4). The proposed design provides a variety of water depths to create a variety of habitats for endangered fishes. A combination of one to four-foot deep areas ' adjacent to the 6-foot channel would be constructed to provide shallow-water areas for the production of aquatic invertebrates and zooplankton. These areas would be "stepped" to form terraces or benches. Two backwaters, part of the ' existing depressions left from the former side channel, would be gently graded toward the 6-foot channel to provide two additional shallow-water habitats. The existing upland areas for game birds would be maintained. Two stop-log structures each with fish screens would be installed to regulate flow and to ' drain the three compartments if desired for fish retrieval or removal. Fish screens would facilitate biological studies by maintaining isolated compartments. Stop-log structures should be installed and placed at elevations necessary to drain 50-75% of the 6-ft deep channel. It will be almost impossible to totally drain the 6-foot deep channels because groundwater from the river will maintain levels at the elevation of the river. Total draining would be accomplished only ' with mechanical pumping. Fish would be retrieved or removed with seines following water drawdown. As part of mitigation for loss of wetland habitat related to the Salinity Control Program, a similar design, but larger, was 14