Rehabilitation of an 8 inch AC Water Supply Line of a Fish Hatchery at Lake Whatcom, WA
November 26, 2018 by NASTT Staff
Project profile submitted by Insta-Pipe – Trenchless Pipe Repair using the Pull in Place pressure liner “PRIMUS Line”.
Insta Pipe, Inc. – Trenchless Pipe Repair, Olympia, WA
Year of Construction:
Type of Project:
Rehabilitation of an 8 inch AC low pressure Water Supply Line in one section of 850 feet
• Supply and delivery of the flexible low pressure 8 inch Primus Liner (ANSI/NSF 61 approved)
• Delivery of the 8 inch Primus Line low pressure connectors (150 psig)
Located just east of Bellingham, WA, Lake Whatcom covers 4,923.6 acres and is home to the Lake Whatcom Trout Hatchery owned by Washington State Department of Fish & Wildlife. Fishing opportunities on the lake include resident Kokanee, Largemouth and Smallmouth bass, and Yellow Perch. Fishing for resident Coastal Cutthroat Trout is currently closed due to a decline in abundance caused by siltation from logging and urban activities in their spawning tributaries. The Lake management is of mixed species with an emphasis on Trout. The task was to provide all labor, material, equipment, and permits to rehabilitate an existing 8 inch diameter asbestos concrete water supply pipe at the Department‘s Lake Whatcom Hatchery, located at 3918 South Bay Drive, Sedro Woolley, WA 98284 in Whatcom County.
In choosing a contractor, technique and product to rehabilitate the 8 inch, 850 feet long water supply line to the Trout Hatchery rearing ponds it was extremely important for fisheries to consider the purity of the product with an ANSI/NSF 61 approval and the minimal impact that the installation would have on the hatchery grounds, stream buffers & surrounding forestland environment and community.
Fisheries chose Insta-Pipe, Inc. to successfully install Raedlinger Primus Line to rehabilitate the pipe-line with extremely low impact rather than to dig and replace the line that ran from a supply dam, crossed a stream and paralleled that stream to its final destination at the Hatchery.
The decision was to install a Primus Line® DN200MD with a nominal diameter of 8 inch and a nominal design pressure of 261 psi. Since the technology works with an annular space to achieve long insertion lengths and negotiate bends, the liner provides an actual outer diameter of 7.165 inch and inner diameter of 6.693 inch. According
to the calculation of the technical department of Primus Line, the pressure rating of the system through the 45 degree bends is 148 psi and thus easily capable of accommodating the maximal operating pressure of 8 psi along the entire pipe route. To complete the system, the specially developed termination fittings were used to guarantee a durable and tensile strong connection. The Insta-Pipe team prepared the construction site and managed to complete the installation of the rehabilitation system in two days. During the entire installation a Fisheries Supervisor was on-site.