The City of Yakima (City) desires to enter into an Interlocal Agreement (ILA) with Yakima County (County) to transfer $4,734,723 Department of Ecology Floodplains grant funds from the County to the City to complete the cooperative design and construction of the Nelson Dam and By-pass / Rambler’s Park project. No City matching funds are required.
Nelson Dam is located just upstream of the twin bridges on SR 12 where the City diverts water for irrigation. It was damaged during the 1996 and 2011 floods and is nearing the end of its life-expectancy. Stall will replace the existing Nelson Dam and the connected fish by-pass. This work will reduce flood risk, impact flood risk maintenance and improve fish habitat conditions, particularly for Endangered Species Act listed Steelhead and Bull Trout, by improving the natural physical processes of the river. The project consists of:
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Demolition of existing site floodplain and channel structures
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Demolition of a portion of the existing Nelson Dam
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Construction of the new 2 acre Nelson Dam boulder by-pass and upstream weir
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Excavation of 2,500 feet of floodplain dam approach channel
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Placement of a road protection structure just upstream of the new Powerhouse Bridge
The City owns the current structure while the County owns the land. Since the structure design was established with basin cooperation and physical model studies, this ILA eliminates conflicts associated with having separate consultants and contractors working on this project. County staff would remain involved in the design and inspection. The ILA is attached for City Council review. |