Wyoming ranch manager, Trout Unlimited collaborate to save fish from irrigation canals

CODY, Wyo. – Fish die in fields, and the irrigation canals that funnel them to farmlands can also become a deathtrap in the fall when water is shut off.

In Wyoming’s Wapiti Valley, not far from the east entrance to Yellowstone National Park, one ranch is working with the local Trout Unlimited chapter to keep fish wet. It’s a task more difficult than it sounds.

“Most of the trout in this system are adfluvial, in other words, they live in the reservoir and come upstream to spawn,” explained Larry Timchak, president of the East Yellowstone Chapter of Trout Unlimited.

Buffalo Bill Reservoir, which can hold more than a half-million acre feet of water, is the local fishes’ migratory starting gate. An acre-foot is the amount of water it takes to cover 1 acre in 1 foot of water.

In the spring, rainbow trout move from the lake into the North and South Fork Shoshone rivers and on to smaller tributaries to spawn. They may be accompanied by a few native Yellowstone cutthroat, although their populations have declined in the watershed.

“So the whole future depends on connectivity between spawning streams and the lake,” Timchak said.

Field work

The Trout Creek Ranch, managed since 2011 by Minnesota-native Cory Williams, has taken a strong conservation stance when it comes to wildlife and fisheries. The ranch regularly sees 500 head of elk and mule deer, while other species such as mountain lions, bighorn sheep, the occasional wolf, black and grizzly bears pass through. Supporting so much wildlife is not something a lot of other ranchers or farmers can afford to do.

“Unlike a lot of people who try to push the environment out of ranching or farming, we try to live within that,” Williams said.

One way the ranch owners, Robbie and Michelle Keith, have promoted their values is by installing three fish screens on irrigation canal headgates. The idea is to block fish from becoming stuck in the canals where death is almost certain.

Trout Creek, which in April could be crossed in two to three large steps, supports an estimated 300 pairs of spawning rainbow trout, Timchak said.

“That seems like a small thing, but every fish we get back in the river counts,” he said.

First in state

The first fish-screening device installed on private land in Wyoming was placed 20 years ago on a small Trout Creek Ranch canal. The waterway only carries about 3 to 4 cubic feet per second of water. That’s a small amount of water compared to some of the bigger canals in the northwestern corner of the state that can carry 250 to 400 cfs of water. Yet the chapter wanted to start small and prove the concept.

“We had to offer them assurances that we weren’t going to disrupt their water flow,” said Dave Sweet, a longtime Cody TU member who helped negotiate the installation.

The screen looks like a small, perforated, stainless steel barrel. Water flowing down the canal turns the barrel which moves any small debris up and over while blocking fish. A pipeline just above the screen diverts fish back into the nearby creek. A “trash rack” blocks bigger debris at the head gate where the water is diverted.

In 20 years, the device only failed once when a beaver attempted to build a dam at the site.

Although small, the price tag for the screen was large: $34,000 that the local chapter raised. The high cost is due to the fact that each fish screen is custom-made to fit a particular site. There’s also not a huge demand for the technology.

Other tech

Upstream a short distance, a different kind of fish screen was installed that requires electricity to operate. The device resembles a tank track, steadily turning to divert debris while still allowing water through.

This device is designed to handle up to 6 CFS off the main creek.

It was installed in 2009 at a cost of about $50,000.

The Wyoming Game and Fish Department helped defray the cost.

The final fish screen the ranch has experimented with is called a Farmer’s Screen, which resembles a long metal flume. Inflowing fish and debris are flushed over the screen while water for irrigation passes through. Williams said the structure requires almost daily cleaning, compared to monthly for the traveling screen and annually for the drum.

Next step

Although the fish screens are working, Williams is planning to install shallow wells to draw irrigation water and pipe it to pivot sprinklers to water the ranch’s fields in the future. That way, although water is being taken from the watershed, it is not being directly diverted from the creek.

The new system will also allow greater control of water flow. Williams and his ranch hands will be able to vary the amount from as little as half-a-tenth of an inch to 1½ inches of water. Key to the system will be a CropX sensor screwed into the ground that provides real-time information on how much water the plants need as well as predictive models via an app on weather, temperature and irrigation management.

In his experiment with the technology on a small field, Williams said the sensor increased crop yields to 5 tons per acre.

“We are hitting yields unheard of for Wyoming, let alone the North Fork,” Williams said. “The average is probably 2 tons.

“That’s a pretty darn good yield no matter where you’re at, but this year we’re predicting that will be closer to 6, on the North Fork, in our climate, in our short growing season.”

One downside

Although the new system will enable Williams to leave about 3 to 5 CFS of water each day in Trout Creek during the summer – as fish eggs hatch and the fry grow – he can’t prevent his downstream neighbors from diverting the additional water.

“To me, that is a tremendous amount of water,” Williams said. “The reality is it will never hit the confluence. All I do is donate that to the neighbors.”

Trout Creek, by the way, has been dewatered on a regular basis, Sweet noted.

“That’s the hard part,” Williams added. “How do you do the right thing, knowing that is having no effect? That’s a tough one.”