Second Fish Kill Detected in Lower Deschutes River

  By Greg McMillan & The Board of Directors of the Deschutes River Alliance

For the second time in a week, we’ve learned about a fish die-off in the lower Deschutes River.  This second fish kill is happening in the area of Whitehorse Rapids (25 miles upstream from Maupin at river mile 77, and 23 miles downstream from the Pelton-Round Butte Dam Complex) and consists of dead spring Chinook salmon.  A cause of death for these fish has not yet been determined.

Dead and dying spring Chinook were first reported by Taylor Geraths of TaylorMade Outfitters on Friday, July 10, and shortly thereafter confirmed on the same day by Deschutes River Alliance board member and Vice-President Damien Nurre, owner-operator of Deep Canyon Outfitters.  Both observed numbers of dead or dying spring Chinook between Whisky Dick Campground (river mile 78) and Nena Boat Launch (river mile 59).

Probable Cause of Death

There are two possible, and even likely, causes of these spring Chinook deaths.  The first is columnaris, which the Oregon Department of Fish and Wildlife believes is killing sockeye salmon at the lower end of the river.  The other is Ceratomyxa shasta, a not uncommon parasite in the Pacific Northwest.  It infects salmonids in warm water conditions.  Rates of C. shasta infections have reportedly been high in Chinook salmon exposed to Lake Billy Chinook (PGE Fisheries Workshop, 2015).

Both of these infections occur when salmonids are in water warmer than their normal and usual temperature range.

We know that these fish have been in the Deschutes River for weeks to a couple of months.  These fish enter the lower Deschutes River primarily in April and May.  So this is not an effect of exposure to the Columbia River that is crippling and killing these fish.  Conditions in the lower Deschutes River are contributing to the death of these fish.

Photo by Damien Nurre.

River Conditions

Water temperatures in the lower river in the past few weeks have exceeded 70 degrees Fahrenheit, and been as high as 75 degrees at the Moody gauge on some days.   According to Rod French, Oregon Department of Fish and Wildlife fisheries biologist from The Dalles Office, in an interview in 2010 (, July 22, 2010), “It's not healthy for fish to be in 70-degree water for long periods of time.”

No one can control the weather conditions that have led to warm water in the lower Deschutes.  But the operators of the Pelton-Round Butte Dam Complex can control the temperature of the water leaving the dams thanks to the Selective Water Withdrawal Tower at Round Butte Dam.  By mixing warm surface water with cold bottom draw water they have an ability to adjust temperature from a low-end of near 50 degrees (the temperature of water near the bottom in Lake Billy Chinook) to over 70 degrees (surface water temperature in Lake Billy Chinook), or to temperatures anywhere between.  During the time of warm water conditions leading up to the two fish kills, the dam operators were discharging water as warm as 60.5 degrees.  When air temperatures are in the nineties, the water doesn’t have to travel far to hit the 70-degree temperature Rod French defined as unhealthy for fish.

This makes the situation in the Deschutes very different from the other rivers in Oregon where fish kills are taking place.  On the lower Deschutes, there is the ability to cool the river using water at depth in Lake Billy Chinook.

Fortunately, the weather has cooled.  River temperatures are dropping from crisis levels.  The dam operators have reduced the temperature of water leaving the dams.  But warm to hot weather will be returning soon.  Another warming trend is forecasted for the end of the week July 13. 

Photo by Andrew Dutterer.

What To Do

The obvious answer is to discharge cooler water from the PRB Dam Complex.  Portland General Electric claims that they can’t do that because their operating license won’t allow them to cool the river.  But the fact is that they have done it (July 19, 2014).

There is language in their license allowing, and even mandating, “adaptive management.” (Water Quality Management and Monitoring Plan, Exhibit A, September 2002).

We believe it’s time to adapt to weather and climate conditions and save fish.

We also note that language in the operating license for the dam complex calls for changes in operations when fish or wildlife are threatened by dam operations.  According to the license (Article 405, Order Approving Settlement and Issuing New License, Project No. 2030-036, Federal Energy Regulatory Commission, June 21, 2005.):

If at any time, unanticipated circumstances or emergency situations arise in which non-ESA listed fish or wildlife are being killed, harmed or endangered by any of the project facilities or as a result of project operation, the licensees shall immediately take appropriate action to prevent further loss in a manner that does not pose a risk to human life, limb, or property.

Similar language also applies to species listed as threatened or endangered under the Endangered Species Act.

What You Can Do

Contact Portland General Electric’s Portland offices.  Let them know that the lower Deschutes River and its fish are important.  Let them know we need cooler temperatures in the river when the weather returns to being hot in another week.

Or call them at:

Community Affairs: 503-464-8599

Corporate Communications: 503-464-8949


Special Thanks

A great deal of work went into preparing this blog post.  Members of the DRA who contributed to this blog include: Steve Pribyl, Andrew Dutterer, Rick Hafele, John and Amy Hazel, Damien Nurre, Cam Groner, and Rick Trout.  I am indebted to them.

Greg McMillan


Deschutes River Alliance: Cooler, cleaner H2O for the lower Deschutes River. 

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