Enhancing Downstream Migration
Pacific Netting Products designed two barrier nets to divert, guide and collect down-steam migrating salmon for Puget Sound Energy. In 1985, The Skagit River annual adult sockeye returns had plunged to a low of just ninety-nine fish, imperiling the stock. For next twenty years, the owner of the Upper and Lower Baker Lake Dams, Puget Sound Energy, invested to improve downstream fish passage into the Skagit. During this time they tested and implemented new collection devises, different types of barrier nets, and made investments in habitat, hatchery and other methods to support the watershed’s fish populations.
Pacific Netting was invited to bid on the manufacture and supply of a new barrier net for the Lower Baker Dam in 2011. While discussing final design and build requirements, a survey done on the Upper Baker barrier net discovered existing material and design failures. A temporary fix was provided while we worked with PSE engineers, and their engineering firm MWH, as well as fish biologists, regulators and contractors and others, to identify and correct the reasons for failures of their existing nets. We helped the team understand solutions; material and technology that could be implemented to meet their goals and objectives and migration concerns. As the pressure for a solution increased from a number of sources, and the time frame to perform decreased, we implemented the engineering, design and manufacturing changes into new nets. Completing our work on time, both the Upper and Lower Baker Lakes, PNP designed, High-Tech Barrier Nets, went into service in October and December 2012, in time for the outbound spring migration.
Full Exclusion Guide Nets, Upper and Lower Baker Lake Dams
The success of these High-Tech Barrier Nets has been proven in fish passage counts, installation and maintenance cost, and in customer satisfaction. Following PSE’s investment in our solutions, and with other system improvements, by June of 2014, over one million downstream migrating salmon were collected and returns of sixty to one hundred thousand adult fish are soon expected.
Full Exclusion Guide Nets at each facility
Upper Baker Lake:
› 2,000 ft. long X 300 feet deep, about 500,000 sq. ft.
› Built with 1/8” x 1/8” and 1/4” x 1/4” Dyneema Netting
Lower Baker Lake:
› 2,400 ft. long X 300 feet deep, 600,000 sq. ft.
› Built with 1/8” x 1/8” and 1/4” x 1/4” nylon
Both designed for extreme pool fluctuations (50 to 70 feet)
Helped PSE achieve record downstream fish passage
Designed for single direction water flow velocities 0.1–0.5 fps
Anchored by shore-side embedments
Deployed year round