Over the Fourth of July weekend, Steve Pribyl was hiking along the lower Deschutes River between Rattlesnake Rapid and Moody when a distressing sight caught his eye. The retired Oregon Department of Fish and Wildlife fisheries biologist and Deschutes River Alliance board member found about 13 dead or distressed sockeye salmon in shallow waters, says DRA Board President Greg McMillan. The apparent cause of death: thermal stress.
Pribyl pushed off in a kayak Tuesday morning to survey the river and look for other fish kills.
With June temperatures reaching highs not normally seen until August, the waters of the Deschutes and other Oregon rivers are heating up, creating dangerous conditions for migratory fish, including an increase in deadly bacteria.
“Normally we see these kinds of conditions later in the summer, not in late June and early July,” said ODFW Information and Education Division Administrator Rick Hargrave, in a recent release. “When streams get too warm, fish are stressed and as a result the fishing goes downhill fast.” Sockeye salmon in particular, McMillan explains, have a lower tolerance for warm temperatures than other types of salmon, making them the “canary in the coal mine.” And in this case, he says, there’s a possibility the fish are not just sensitive, but endangered.
“One thing we would certainly like to know is if any of these fish are listed sockeye from Idaho. The timing is right,” McMillan says. “If these are endangered that would be huge.”
Craig Banner, a senior fish health specialist for the ODFW, says he’s not aware of the recent fish kill, but points out they do happen from time to time. He adds that his lab in Corvallis has been analyzing a half-dozen spring Chinook salmon found under the falls near Oregon City, who all appear to have succumbed to a bacteria that thrives in warmer waters. The ODFW lab in Madras did not return a request for comment by press time.
“The bottom line is we’ve had exceptionally warm waters,” Banner says, adding that while early exposure to warmer temperatures can cause fish loss, he isn’t aware of any major fish kill events so far this year.
And either way, he figures there’s only so much that can be done.
“I don’t talk directly to any deity,” he explains, “so there’s not a whole hell of a lot we can do about it.”
But the Deschutes River Alliance is urging Portland General Electric and The Confederated Tribes of Warm Springs, who co-own and operate the Pelton-Round Butte Dam Complex, to release more cool water into the lower Deschutes.
“Last summer, 2014, the dam operators elected to lower discharge temperatures by using more water from the bottom of the reservoir.ย We think it’s time to do that once again,” McMillan wrote in a post on the DRA website.
Portland General Electric spokesman Steve Corson says that isn’t likely to happen. He confirms that Round Butte operators shifted the balance of water being drawn through its selective water withdrawal tower as an experiment
“Nobody likes to see a situation where you have a fish kill, but we need to be careful not to respond in a manner that responds to the concern of this week but might limit our ability to respond to the needs of the future,” he explains. “There’s not an infinite supply of cold water at the bottom of the river.”
Instead, the dam operators aim for something called “natural thermal potential,” essentially a scientific estimate of what the water temperature would have been in the river had the dam not been there.
Currently, Corson says, they are pulling 25 percent of their water from the bottom of the reservoir and 75 percent from the top, resulting in an output of about 59 degrees at the facility. But, he explains, that temperature rises to about 73 degrees at the mouth of river, due to warm, sunny conditions as it passes through the canyon.
“We are learning along the way, and we have made adjustments along the way. But when we do that we need to base that on the best science that’s available,” Corson says. “It’s not something where PGE can say, ‘It’s really hot, let’s lower the water.'”
With temperatures in the canyon approaching or exceeding triple digits, he says that decreases in the water temperatures coming out of the dam would have little impact on temperatures at the mouth of the Deschutes.
Still, Corson notes that outputs are likely to get cooler in the “relatively near future,” largely due to cooler days ahead, and the resulting reconfiguration of the natural thermal potential.
“The bottom line for us, we appreciate the frustration of some of the river users who are naturally upset when there are conditions like we’re seeing on rivers in Oregon right now,” Corson says. “We care about the river and the health of the fish as well.”
But DRA’s Greg McMillan is not convinced that pulling cooler water at the dam won’t impact the mouth of the Deschutes, or that it will hamper the facility’s ability to draw colder water later in the summer.
“Last year they did an experiment, pulling 65 percent colder water on July 19 and their cold water supply lasted into September,” McMillan says, adding, “That could be seen all the way to the mouth through the temperature gauge at Moody.”
In general, McMillan expresses distrust for PGE, explaining that the agency has been less than forthright with information in the past.
“We tried to work with them collaboratively for over two years,” he says, “and mostly what we got was stonewalling, foot dragging, and obfuscation.”
This article appears in Jul 8-16, 2015.
MAKE LOCAL JOURNALISM HAPPEN
Republish our articles for free, online or in print, under a Creative Commons license.
PGE to fish: Drop Dead.
Hummm… The DRA in their own analysis in various documents (and as Greg McMillan has said in various forums) has confirmed what PGE and ODFW’s analysis has shown: by the time the water makes it’s way down the river towards anywhere near the mouth of the lower Deschutes the temperature in the river is completely dependent on air temperature. The temperature of the water being released at the bottom of the PRB dam complex in this stretch has no impact.
PGE and the Tribes operate PRB per their FERC operating agreement which calls for them to maintain the river at the temperature that it would be at if the dams were not in place, which is exactly what they are doing. They continue to modify their output regime, but it is only fiddling at the margins.
Let’s face it: global warming is real. The past 2 summers have been the warmest on record and this summer could be warmer still. The Columbia is the warmest it has ever been right now as well. We can look for scapegoats but that is not going to cool off our summers and lower the water temps. Asking PGE to counteract the warmest air temperatures on record is an interesting request. As stated in the article, there is only so much cold water at the bottom of the reservoir. As the release protocol calls for, they will start to release it in larger quantities in August when the anadromous fish need it to start their journey upriver to their spawning grounds in earnest. Hopefully, air temps will recede then as well as the days get shorter.
This is an emotional issue for many anglers. As an avid steelhead angler I too am distressed by the water temps and it’s impact on a fishery I love, but we need to stick to the best available science. Many of us think dams are bad and should be removed. Current river temps mimic what they would be if that were to happen.
Yancy is right. We need to stick to the science. Our own data, and PGE’s data as reported by Charles Huntington in the PGE funded and published report, “Water Temperatures in the Lower Deschutes River, Oregon,” indicate that temperatures throughout the lower river are impacted by dam release temperatures. From the Huntington report: “Our modeling suggests that PRB affects river temperatures all the way downstream to the mouth.” (page 45). Last year when PGE reduced dam discharge temperatures on July 19, the impact was clearly seen within 36 hours at the Moody temperature gauge near the mouth of the Deschutes River. Right now we only need a few degrees cooler water to benefit fish.
As of today, PGE is continuing to increase dam release water temperatures despite already warm temperatures and record heat. The cold water supply from Lake Billy Chinook that was utilized last summer reportedly lasted until September. When shorter days and cooler temperatures prevail.
Greg McMillan Deschutes River Alliance
Greg,
This is not the right forum for one of our typical interactions, but I did want to bring attention to the press release from ODFW this morning on this very topic:
http://www.dfw.state.or.us/news/2015/july/…
After analyzing the fish they have determined that water temps in the Deschutes had nothing to do with the recent mortalities. These were Columbia fish, not Deschutes fish, who secumbed to the record high temps in the Columbia and resulting bacterial infection.
The entire western US is in the grip of a multiyear dry cycle / drought. Rivers throughout Oregon are at extreme lows with high temps. As a result, ODFW is limiting or closing fishing on a wide scale. They may have to do so on the Deschutes as well.
I truly wish the solution was in the hands of PGE, but the issue is much larger.
Yancy
https://deschutesriveralliance.wordpress.com