Bateman Island is connected to the City of Richland by a short earthen causeway at the confluence of the Yakima and Columbia Rivers. The presence of the causeway has altered flow and water quality conditions in the Delta and created a water temperature barrier that can delay adult salmon migration. Flow modeling indicates that salmonid migratory conditions in the Delta would improve with causeway breaching. The Mid-Columbia Regional Fisheries Enhancement Group will identify alternatives to breach the causeway to allow flow along the south side of the island while accommodating recreational and emergency access to the island. The project will also identify and address the concerns of stakeholders in the area, including the landowners (Washington State Department of Natural Resources, US Army Corps of Engineers), lessees (City of Richland, Columbia Park Marina), and recreationists. Alternative development will consider: mobilization of sediment deposited to the west of the causeway, bank scour, reduction of rearing habitat for non-native species, protection of marina resources, and relative project costs. Monitoring of water quality parameters and fish utilization will continue throughout the alternative development process. The goal of this project is to design alternatives for improving migratory conditions for juvenile and adult steelhead, spring, summer, and fall Chinook, coho, and sockeye salmon at the confluence of the Yakima and Columbia Rivers.