Client: Chelan Public Utility District & Washington Department of Fish & Wildlife
Location: Washington, US
Date Completed: 2008
Highlights: Challenges with limited water resources were successfully solved.
The Chelan County Public Utility District (P.U.D.) was mandated to increase Chinook salmon production but faced limited water resources and permitting challenges. In 2008, a pilot program was devised to investigate alternatives to the traditional aquaculture methods and determine if those methods may be applied to help meet the P.U.D. program objectives.
The focus of the pilot program was the construction, operation, and evaluation of a Partial Reuse Aquaculture System (PRAS) incorporating circular culture tanks with dual drains. PRAS have been successfully applied elsewhere to improve rearing volume utilization, reduce site footprint, improve control over culture conditions, and dramatically reduce water consumption and energy costs.
The pilot PRAS was installed at the Eastbank Fish Hatchery and was used to rear Chinook salmon from ponding to yearling size. The pilot was evaluated relative to a flow-through raceway culture unit of equivalent volume. The pilot was evaluated on a broad range of criteria including water quality, fish health and survival, and energy consumption.
The results of the pilot program have been very positive, indicating that the PRAS delivered comparable fish growth, greater smolt survival, reduced precocity, and improved smolt-to-adult returns (SAR). As a result, PRAS technology is being considered for adoption in the continued efforts of the CPUD to expand and modernize their hatchery facilities. Further studies to evaluate other species, alternate fish rearing densities, and adult return data are ongoing today.
PR Aqua provided bio-programming, system planning and design, equipment selection, tender support, construction review, commissioning, and operational assistance. This project solidifies PR Aqua’s expertise with multiple salmonid species, the ability to deliver large scale projects with high quality, and the ability to work collaboratively with a large multidisciplinary design team.