The Kennewick Irrigation District’s Kiona Intake and Booster Pump Station project is a new 6,300 gpm pump station and freshwater intake facility located off the Yakima River. The construction of the $5.3 million Kiona Intake and BPS is part of a larger $15.2 million construction project that will deliver irrigated water to the prestigious Red Mountain American Viticulture Area. The booster pump station functions as the main supply source for the newly developed Red Mountain South LID irrigation system, which will serve over 1,700 acres of irrigable lands where some of the region’s finest wine grapes are grown.
The pump station includes five vertical turbine pumps, with two 20 hp motors and three 300 hp motors, each equipped with variable frequency drives. Water from the pump station is filtered to remove particles larger than 100 microns. This level of filtration is unique in comparison to other municipal irrigation systems where the owner typically assumes no responsibility for the water quality being delivered to the end user.
RH2 was retained to design, permit, and provide construction assistance for the project. As part of the permit compliance efforts, RH2 completed wetland delineations and demarcated the ordinarily high water mark of the Yakima River. Permitting involved significant coordination between the local, state, and federal agencies with jurisdiction, including Benton County, the Washington State Departments of Fish and Wildlife and Ecology, the US Army Corps of Engineers, the US Fish and Wildlife Service, and the National Oceanic and Atmospheric Administration – National Marine Fisheries Service.
The environmental permitting for the project presented a number of challenges due to the site’s proximity to the Yakima River, which provides a habitat for salmon listed on the Endangered Species Act. As a result, access to the river during the construction of the intake structure was limited and confined to a narrow 2-month window from mid-July to September. In addition, the topography of the site made access extremely difficult, which was further complicated by the fact that the entire site is predominantly basalt bedrock. The project required extensive rock blasting, excavation, structural earth retaining walls, and grading to prepare the site for the new facility.