Deep in the Yakima River Canyon, the fish were practically flying.
Soaring 100 feet above the river at speeds up to 20 mph, spring chinook were shooting through a tube designed to carry salmon over dams in seconds, at far lower cost and faster construction than traditional fish ladders.
“We’re pretty excited about the possibility of using this type of technology; it’s such an efficient way to move fish,” said Walt Larrick, project manager with the Bureau of Reclamation, which has pledged to build fish passage at the five dams it operates in the Yakima Basin.
Nicknamed the “Salmon Cannon,” the system is basically a flexible sleeve that seals around each salmon so that only a small amount of air pressure is needed to fling the fish. A biologist at Roza Dam’s fish collection facility feeds them into the tube, and about 35 seconds later, they land in a hatchery truck parked 1,100 feet upriver.
The technology was developed by Seattle-based Whooshh Innovations, and a smaller system was first tested on live fish by the Yakama Nation’s fish biologists at Roza Dam in 2013. The success of that study and others around the region inspired Reclamation to sponsor this first dam-sized test on about 60 fish over the past three weeks.
“The fish just zoom along,” Larrick said of the system. “When a fish goes through a fish ladder, it is burning energy every step of the way, but in this system, it’s riding.”
And the salmon don’t seem to mind the ride.
The Yakama Nation has tracked the survival of every fish that’s traveled through a 40-foot Whooshh tube that connects its collection facility at Roza Dam to a hatchery-bound tanker truck and the success of those fish’s offspring and found no ill effects.
“It’s less stress on the fish,” Yakama Nation biologist Mark Johnston said of the short system.
And reducing that stress on returning spawners across the region with Whooshh tubes at dams could have big impacts on salmon recovery, he said.
“It takes hours to days to get up ladders, so this saves a ton of energy for each fish, which is more energy for heading upstream and more energy for developing eggs,” Johnson said.
Initially, Whooshh tested a vacuum pressure system that pulled fish through the tube, but now the fish are pushed by an “accelerator” that creates lower air pressure in front of each fish and more behind them, like a pneumatic tube at the bank, said Whooshh CEO Vince Bryan.
“They just glide because there is essentially no friction in the tube,” Bryan said.
Pushing also allows the tube to accommodate multiple fish at one time, he added.
That’s key to the system’s potential for fish passage, Johnson said.
“At Cle Elum Dam, we’d want to see a bank of different-sized tubes so that all the native fishes that want to be able to get up into the lake can,” he said.
That vision of fish access — long advocated for by the Yakama Nation — could be a reality in just a few years, Larrick said. When the basin’s storage dams were constructed almost a century ago, they blocked access to mountain lakes and tributaries, and salmon populations, particularly lake-loving sockeye, plummeted.
Plans are in development to restore access by building fish passage onto the existing dams as part of the Yakima Basin Integrated Plan for improved water management in the region.
“In the integrated plan, we the bureau made a strong commitment to put fish passage on all the reservoirs, but one of the things that’s driving interest in this is the cost of adult passage is really expensive,” he said.
The proposal for Cle Elum dam is to build a small fish ladder and collection facility from which returning spawners can be trucked around the dam and dumped in the lake. That alone would cost about $20 million to $30 million, Larrick said.
“If we could do this for half that or less, and do it in one or two years instead of five or six, that would be great,” he said.
This study and the 1,100-foot-long system cost the bureau $250,000, Larrick said.
But installing a similar system at Cle Elum would cost far more, because the transport tube itself is only a small part of the price tag. The equipment necessary to allow fish to swim themselves into the tube is more complicated to construct, Bryan said.
It’s basically one step of a fish ladder that attracts and collects the fish before funneling them down toward the tube entrance. Last summer, Whooshh tested a self-entry system at a diversion dam on the White River in Pierce County and “when we opened the gate, the fish would just dive right in,” Bryan said.
Even with the entrance system included, Bryan said that of all the project proposals Whooshh is working on, the system is never more than 20 percent of the cost of a traditional ladder.
The entry system combined with the 1,100-foot tube will be tested this fall at the Yakama Nation’s Prosser hatchery, Larrick said.
If that test is as successful as the past few weeks at Roza have been, Larrick said he’s optimistic that a prototype could be set up at Cle Elum Dam next summer.
The bureau’s focus is on the five Yakima Basin storage reservoirs that lack fish passage, but Bryan said Whooshh’s systems could also provide a better alternative to existing ladders at some dams.
Ladders take a lot of water to operate and it’s usually warm water from the surface of the river above the dam. During last summer’s heat wave, that hot water deterred fish from using some ladders, Bryan said.
In contrast, the Whooshh system uses just a little bit of water, so it would be easier to pump in cold water from deeper in the river to attract fish to the entrance, where they would then be whisked upstream toward cooler areas, he said.
Across the country, Whooshh is designing proposals or planning out about 60 different passage projects, Bryan said. But many of those projects are waiting on the company to get approval from the National Marine Fisheries Service that the technology is safe to use on endangered species. Working with the Bureau and the Yakama Nation to collect the data on long-term impacts is key to that effort, he said.
“We need to get the data to prove that this technology is as good or better than the approved way of moving fish,” Bryan said. “That will allow us to solve a bunch of problems quickly. We can solve 10 problems for the price of one.”