July 2021 – Fall 2023
Located just west of Yakima, where West Powerhouse Road and Highway 12 cross the Naches River, the Nelson Dam has stood in service to the residents and farmers of Yakima for just shy of 100 years.
Documented in the Board of Trustee minutes from 1934, The NCCA Board authorized the borrowing of $5,000 to cover the Company’s share of construction cost for the new Nelson Dam across the Naches River. The dam was to divert irrigation water from the Naches River to feed Naches Cowiche Canal and City of Yakima irrigation water lines. The original dam did not include fish passage. It was rehabilitated in 1961 at a total cost of $25,142, but a fish ladder was not installed until 1985.
Presently, after a decade of planning, the Nelson Dam is being removed.
Work began in July 2021. Phase 1, dam removal and infrastructure construction, is expected to be completed by April 2023. Contractors must be out of the river from Feb 28 to July 16 to avoid disrupting fish migration. Phase 2, piping integration, is expected to be completed by Fall 2023.
The completed project will consolidate the current diversions for Naches Cowiche Canal, New Schanno, Old Union and the City of Yakima lines into one intake complete with fish screens and silt management. Once completed, the removed dam will be replaced with a roughened channel in the river allowing fish and boaters to move freely along the river for the first time in decades. Over 300 miles of uninhibited waterway will be opened up on the Naches and Yakima Rivers. Along with fish passage and recreational use, improvement to water supply reliability, flood water management and sediment continuity affecting immediate habitat will also be realized.
The $18.1 million cost of the project is a multi-agency collaboration.
Power Point of Preliminary Project
Y-PAC Check-ins host Sean Davido interviews the City of Yakima’s Assistant Public Works Director, Dave Brown, for an update on the Nelson Dam project on the Naches River. – October 2021
