After final completion of the Nelson Dam removal and new irrigation diversion in 2022, phase 2 of the project is scheduled to begin.
Interwest Construction, Inc. (ICI) of Burlington, WA is scheduled to start work today, Monday, October 14th. Initial work will include mobilization of materials and equipment to the City of Yakima irrigation reservoir site on the south side of Highway 12 near Cowiche Creek. Clearing will also take place in preparation of crossing Cowiche Creek. Work to isolate the work area within Cowiche Creek and provide a temporary diversion for the creek flows will take place over the next few weeks in preparation to install new 32-inch and 42-inch irrigation pipelines across Cowiche Creek.
The Nelson Phase 2 pipeline project will install new irrigation main lines from the new Nelson diversion, east along Hwy 12, to the existing Fruitvale irrigation canal near the N. 40th Avenue interchange.
When complete in spring of 2026, the new pipelines will provide irrigation from the Nelson diversion for the city’s General and Fruitvale irrigation systems, as well as the Old Union Canal system. The pipelines will allow the existing Fruitvale and Old Union irrigation diversions to be abandoned and make way for a flood plain restoration project by Yakima County around the confluence of Cowiche Creek and the Naches River.
The City of Yakima, Yakima County and numerous other state and federal agencies have been collaborating on the design and implementation of this project for the past decade. The Nelson dam removal and new pipelines is one of several major public works projects initiated and supported by the Yakima Basin Integrated Plan.
Initial funding for the Nelson Phase 2 project will come from a $7.6 million grant provided by the Department of Ecology as part of the State of Washington’s biennial budget for the Yakima Basin Integrated Plan.
In addition, once a final grant agreement is in place, $5 million in grant funding will be provided by the US Bureau of Reclamation through their WaterSmart Aquatics Ecosystem Restoration Program. This additional funding is part of a nearly $11 million joint funding package awarded to Yakima County and their Cowiche Confluence Complex project.
For more about the project, contact City of Yakima Water/Irrigation Manager Mike Shane at 509-576-6480 or at mike.shane@yakimawa.gov.