Request for a Debris Boom to Help the Salmon
After a successful project for salmon recovery in Upper Baker Lake in 2011, Pacific Netting Products was asked to come back for a related project. In 2019, we installed a Floating HDPE Debris Boom to direct the juvenile salmon safely through the hydroelectric generating system of Lower Baker Lake, and keep woody debris out of the netting.
1 Million Salmon Saved from Near Extinction
Puget Sound Energy operates two hydroelectric generating stations on Upper and Lower Baker Lake. The construction of the Lower Baker Dam in 1927 and the Upper Baker Dam in 1958 prevented sockeye salmon and steelhead from accessing essential freshwater habitats. The challenges with downstream passage had a drastic impact on the survival of these fish runs, and by 1985, only 99 adult sockeye salmon returned to the Baker River.
Concerned, the Puget Sound Energy contracted PNP to design, fabricate, and install a fish guidance net system at the Upper Baker Lake Dam in 2011. The installation of the net significantly extended the shoreline, greatly enhancing the passage of juvenile salmonids. As a result, over one million downstream migrating salmon were saved.
Sockeye salmon in a holding pond. After entering Puget Sound Energy’s fish trap on the Baker River, adult sockeye are trucked to locations upstream, including this holding pond at WDFW’s Baker Lake Hatchery, as well as into the lake to spawn naturally in the Upper Baker River.
“It’s a record-smashing season for young salmon migrating through the Baker River in the North Cascades of Washington State.” Washington’s Baker River Reaches All Time Record—One Million Salmon Are on Their Way to the Pacific Ocean, NOAA News posted in 2014.
Managing Woody Lake Debris with a HDPE Boom
Despite the project’s success, Puget Sound Energy soon recognized another challenge. Large floating woody debris was getting into the system and affecting the fish guidance net’s performance. To address this issue, they once again partnered with PNP to protect the fish passage system with a floating debris boom.
PNP designed, fabricated, and installed an 1,800 linear foot, 24-inch diameter HDPE floating debris boom in Lower Baker Lake. This boom was constructed from bright orange HDPE material. It incorporated several key features to improve its effectiveness, including:
- A 4-foot debris guidance skirt (PNP U.S. Patent No. 29,610,480) was added to act as a barrier against debris at any pool elevation. The skirt was made of 440-ply nylon reinforced rubber, ensuring its durability and resilience.
- A splash guard was included to prevent fine woody debris passage. Specifically, protecting it from smaller debris, such as needles, leaves, and bark. The splash guard kept debris from over-topping the boom during high wind conditions.
- A boat gate was also integrated into the system. Moreover, it was designed with tensile strength equal to that of the boom itself. This ensures the system can withstand high load scenarios without compromising performance.
Innovative System Success
Thanks to PNP’s innovative solution, the floating debris boom has successfully eliminated heavy woody debris that once burdened the fish guidance system. Moreover, it enhanced compliance with FERC regulations, increased public safety, and raised awareness of environmental preservation efforts at the dam.
The Baker River program has been so successful that Baker sockeye are now being transported to the Skokomish River for use as broodstock to jumpstart a recovery program led by the Skokomish Tribe and Tacoma Power with support from WDFW. The hope is this effort will replicate the success seen in the Skagit Watershed and create future fishing opportunities, including in Lake Cushman. ~ ‘Great success’: Baker River sockeye reach record number, The Washington Department of Fish and Wildlife, Reposted by the Medium.
Client: Puget Sound Energy
Date: 2019
Location: Lower Baker Lake Dam, Washington
View Printable PDF Case Study: Puget Sound Energy Lower Baker Lake Guidance Netting (Concrete, Washington)
