Temperature Curtain Improves Salmon Habitat

Presented by the Fabricated Geomembrane Institute Photo: Bob Gee Gee Bob Photo:

By Bob Gee, Bureau of Reclamation, Greg Morris, Bureau of Reclamation & Stanford Slifer, Watersaver CO.

A temperature curtain reaching depths of 100 feet in rafts and roofing. “The holes were caused by recently replaced curtains originally installed in the curtain rubbing against chains linking buoys both the upper and lower reaches of Whiskeytown holding the top of the curtain to anchors on the Reservoir in the early 1990’s. Located at the lake bottom,” Gee said. Whiskeytown Reservoir approximately 10 miles west of the city of Redding, in Shasta County Cali- "It just had deteriorated," said Brian Person, man- fornia, the purpose of the replacement curtain is ager for the bureau's Northern California Area Of- to lower the temperature of the Sacramento River fice at Shasta Dam. "So it was time for a replace- for fish spawning which would restore the Chinook ment." The old curtain was removed in the fall of salmon runs to this part of the Sacramento River. 2010 and the new curtain was installed and made operational in June 2011. Due to the deterioration of the temperature curtain at the mouth of the Spring Creek Power Erick Ammon, Inc. was chosen by the California Plant, plans were made for a complete replace- Bureau of Reclamation to do the job. Nestled ment. According to Bob Gee, a mechanical engi- among the hills and valleys of California’s Klamath neer for the bureau's Northern California Area Of- Mountains, the Whiskeytown Lake curtain serves fice, the old curtain, installed in 1993 had a lot of as a barrier to keep warm water from the Carr holes in it. The original temperature curtain was Powerhouse from mixing with cold water that is made of Hypalon®, a synthetic rubber also used necessary for salmon reproduction. This allows

Temperature Curtain Improves Salmon Habitat Photo: Greg Morris Morris Greg Photo:

Photo 1: Map of the Whiskeytown project area the cold water to go into a tunnel leading to the installed in wastewater lagoons, industrial waste Sacramento River. (see Photo 1) This is achieved ponds and fish hatcheries. It took approximately by creating about a 30-foot-gap between the bot- 260,000 square feet of 60mil (nominal) rPP black tom of the curtain and the bottom of the lake geomembrane to complete the job. through which the cold water flows. According to Gee, finding an open area ashore Bureau engineers redesigned this curtain using a large enough for assembly of the curtain was a 60-mil-reinforced polypropylene geomembrane challenge. “Working with the National Park Ser- (rPP) manufactured by Carlisle Syntec. It was se- vice, we were able to utilize a parking lot at a lected in part because the Bureau of Reclamation beach prior to the summer recreation season,” desired to try a different material. Reinforced says Gee. “It measures 2,400 feet in length and polypropylene geomembranes are most commonly reaches depths of approximately 100 feet . The Photo: Bob Gee Gee Bob Photo: Gee Bob Photo:

Photo 2: Assembly of the curtain on the shoreline Photo 3: Shoreline fabrication 2

Temperature Curtain Improves Salmon Habitat

ternational Lining Technologies (Reno, NV) con- quered the challenges. Coordinating specific panels and various sizes in the proper order per project drawings proved to be one of the greater challenges during installation. Topography of the lake bottom was little known. Divers were sent down to accurately measure the depths of the lake to ensure each panel sizing matched the lake contours. Watersaver Company, Inc. (Denver, CO) then had the difficult task of custom fabricating panels to the contour of the lake. Nearly half of the panels needed to be hemmed on a diagonal. Photo: Bob Gee Gee Bob Photo: An onsite field inspector was provided by Recla- Photo 4: Crane setting a float onto the frame. mation’s Mid Pacific Construction Office to ensure quality fabrication and installation. See Diagram 1. curtain was hot spliced on the reservoir shoreline Another challenge was presented by the onsite and assembled as one continuous sheet of poly- welding process which used a conveyor system in propylene.” order to make necessary fusion welds per material specifications. The job also required the reuse of Installation procedures were truly unique and In- the existing upper boom floating tanks or replace-

Diagram 1: Take-off for the temperature curtain.

3 Photo: Stanford Slifer Photo: Bob Gee Photo 5: Eighty pound metal weights (foreground) (foreground) weights metal pound Eighty 5: Photo used to secure the curtain. curtain. the secure to used was designed to conform to the reservoir bottom bottom the reservoir to toconform was designed It weights. 800 pound by and anchored floats metal to20-foot-long was attached curtain The shor to shoreline voir from reser- of the contours conform tothe curtain the all toremaininplac were tankswhich and surfacestabilizing hardware, cable and chain, and associated lake anchors anchors, shore including components existing of asthereuse as well tanks, newfloating ment with Photo 7: The floats and the curtain were deployed deployed were curtain the and floats The 7: Photo using a conveyor system. system. conveyor a using

Temperature Curtain Improves SalmonHabitat e. The job required that that required job The e. eline, floating vertically. 4 Photo 6: Geomembrane curtain was clamped in the the in clamped was curtain Geomembrane 6: Photo Gee, the new 2,400-foot-long curtain should last last should curtain new 2,400-foot-long Gee, the to According June 2011. in ahead ofschedule amonth completed project The $3-milliondollar low KeswickDam. be- River Sacramento the into blended eventually are Plant Power Creek Spring from Discharges intakes. plant power the into and curtain the pass under to water colder allows bottom curtains contours whileagapatthe Photo 8: Metal floats in place and curtain ready to be be to ready curtain and place in floats Metal 8: Photo metal floats before being deployed. deployed. being before floats metal anchored to the river bottom by 800 pound weights. weights. pound 800 by bottom river the to anchored

Photo: Bob Gee Photo: Stanford Slifer

Temperature Curtain Improves Salmon Habitat Photo: Bob Gee Gee Bob Photo: Photo 9: The conveyor system for pulling the curtain out into the river during the installation process is visible in this picture. at least 15 years. Data is being archived to deter- Authors: mine the temperature curtain performance. To Bob Gee, Bureau of Reclamation, Mechanical Engineer date, the curtain is performing as designed. It is Greg Morris, Bureau of Reclamation, Chief Engineer anticipated to achieve a 2 to 4 degree drop in wa- Stanford Slifer, Watersaver Co. President ter temperature.

This curtain will allow the salmon and the power plant to co-exist in the same river. As more de- mands are placed upon our natural resources, more innovative solutions such as this will need to be implemented.