Confluence was retained by the Wyoming Game and Fish Commission to develop conceptual alternatives for reactivating and maintaining two side channels of the Green River on the Seedskadee National Wildlife Refuge. Long term monitoring efforts indicated a reduction in Green River side channels following construction of the Fontenelle Reservoir in 1965. Confluence completed a topographic survey and developed a hydraulic model to aid in developing conceptual design options for each project site. A hydrologic investigation of the Green River pre- and post-dam construction was conducted to analyze sediment transport patterns and causes for side channel deactivation over time. Confluence developed three conceptual alternatives for maintaining or reactivating two side channels for use by rainbow trout, brown trout, and kokanee salmon.
The Wyoming Game and Fish Commission and the Seedskadee National Wildlife Refuge adopted a preferred alternative for the Double Sill site and contracted Confluence to prepare a final construction design. The preferred alternative included installing a ramp across the river to maintain target flows down the side channel as well as an irrigation ditch on the opposite side of the river in order to provide water to a series of constructed waterfowl wetlands. The project was constructed by the Seedskadee National Wildlife Refuge in August, 2012.