Riverside Pumping Plant Replacement Project latest in decades-long effort
By Gary Pitzer, Bureau of Reclamation
The fish travelling the Sacramento River between the upper Sacramento Valley and the Pacific Ocean contend with a variety of perils as they make the journey.
The river’s path has been highly modified and separated from its historical floodplain for more than a century, enabling homes and farms to exist at the very edges of the levee system.
Altered flows, fluctuating water temperatures, diminished food and habitat and losses from predation mean the threatened and endangered Chinook salmon runs face tremendous odds in surviving their life cycle journey.
Scattered along the river are intakes, large and small, that divert water for agricultural use and valley communities. Unscreened, these structures can take their toll by sending fish on a one-way trip out of the river. It’s a problem Reclamation and its local, state and federal partners have been working to solve for 30 years.
“There might be upwards of 50 large diversions between here and Redding, and each one was having a negative impact on fish,” said Rod Wittler, a civil engineer in Reclamation’s Bay-Delta Office. “They were taking fish. By screening [the diversions], that loss goes to practically zero.”
Wittler spoke during a recent visit to the Riverside Pumping Plant Replacement Project, a $10.5 million undertaking funded partially by the Central Valley Project Improvement Act and completed in partnership with U.S. Fish and Wildlife Service, state, and local partners. As a part of the pumping plant replacement, Reclamation-funded fish screens were installed at the facility.
Steve Whiteman, CVPIA administrator for the Service, said Riverside is part of “the concerted effort” to reverse the decades-long decline of Central Valley salmon. “As with other CVPIA-supported efforts, the Service is pleased to work with Reclamation and willing partners to help reduce the threats faced by juvenile salmonids on their long migration to the ocean,” he said.
Located about 10 miles northwest of downtown Sacramento, the Riverside project is one of the last of a group of projects identified by the CVPIA for screening large diversions on the Sacramento River. The mechanism is smooth and amazingly effective – a rotating drum that operates imperceptibly in the underwater environment. It’s a 100% improvement on the previous operating system that left fish vulnerable when the intakes pulled water from the river.
The pump location, within earshot of Sacramento International Airport, “is a major corridor for migratory fish,” said Jenna Paul, a civil engineer in Reclamation’s Bay-Delta Office.
“This project is important because as the fish are coming down the river, they encounter all these obstacles, whether it’s high flows, different hydraulic conditions, availability of food and predation,” she said. “These juveniles have such a challenge just to get down to the Pacific Ocean that this screen eliminates one possible threat to their life cycle.”
The water is drawn from the river for the Natomas Central Mutual Water Company, which operates its diversions from April to October during which multiple runs of Chinook salmon, steelhead and sturgeon are moving past the Riverside diversion.
“This facility being modernized through this program and having a fish screen on it, allows us to pump water year-round, without issues to species in the river,” said Brett Gray, general manager with the water company. “It allows us to get water to our growers and other habitat lands in the Natomas Basin.”
The collective efforts to protect fish, such as habitat improvements and screening diversions, are like the many buttresses that keep a bridge intact, said Wittler. “One by one, we’ve been removing stressors from the river and cumulatively, that adds up to quite a beneficial impact to the fish,” he said.
