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' constructed upstream of the Escalante SWA at Confluence Park. This was a joint venture between the U. S. Soil Conservation Service, CDOW, City of Delta, and ' Ducks Unlimited (Personal Communication, Paul Obert, 1994). The inlet may have to be relocated upstream of state controlled property ' on an adjacent landowner's property to acquire the slope needed to deliver water to the site. The inlet structure would be situated at an minimum elevation so that spring high water flows would enter the site. Although it might be desirable to flush the site with water from the river at other times of the year, ' the elevation of the river at low flows may preclude this action, regardless of the inlet elevation. Lateral subsurface percolation of river water into the 6- foot deep channel during low-water periods should maintain an adequate water ' level in the site. A constant surface flow through the site would not be necessary because historically many of these off-channel areas were only connected to the river during spring runoff. Following runoff, the standing ' water left should warm quickly that will provide good primary production and fish growth. Although not preferred, as a contingency, irrigation water returning to the river along the drainage ditch to the east of the tract could be diverted to maintain water levels in the site. The 6-foot deep channel will provide a ' hydrological connection to the river to maintain water levels and also provide a deep-water fish habitat to minimize avian predation and provide overwinter habitat. n The outlet structure could be incorporated into the existing cement spillway. This possibility will be explored during engineering, planning, and design. The existing upland acreage would be slightly reduced. However, the diversity of habitats from the proposed development will increase biodiversity at the site and improve habitat for upland game and waterfowl. Public access to this area would not be affected by the proposed action. Site 2. Specific Management/Research Objective: 1. Develop a large backwater habitat that will provide access one out-of-every-third year during spring-high water to drifting larval razorback sucker and adult razorback sucker. The restoration strategy at this site (Figure 5) is less elaborate than ' that described for Site 1. The strategy here would be to re-establish connectivity with the oxbow/backwater to the river more frequently during spring high flows than now occurs. The design and concept originally proposed at the ' 29-5/8 Road Gravel Pit site on the Colorado River (Valdez and Wick 1983; Cooper and Severn 1994e) might be appropriate for this oxbow. Modification of this oxbow would bring the ground surface closer to that of the river so that it would be more active approximately every third year (Cooper and Severn 1994c). The ' site presently has a gently sloping grade (1 foot in 250 feet) with only a 2-3 foot sand/loam berm that separates the river from the oxbow. A stepped or gently sloping cross-section with the deepest section sloping toward the river would be ' created allowing water and fish access in and out of the oxbow/backwater. The productive nature of this shallow embayment could provide vital fond resources for larval fishes, as well as resting and feeding areas for adults. This site ' 16 11