DRA Releases Reports

On March 4, we posted two new reports under the “Reports” tab on our website.

The first report is the analysis of our 2014 thermal imaging survey of the lower Deschutes River.

Slide1

This report is the analysis of the first known thermal imaging look at mid-summer temperature behavior in the lower river.  There were many unanticipated surprises from the imaging, but two findings are of greatest importance.

  • The thermal behavior of water discharged from the Pelton-Round Butte Complex during nighttime hours is unaffected by “canyon effect.” Canyon effect warms the water during the day as a product of solar radiation exposure.  Nighttime discharge, however, avoids much of the daytime warming effect.   Yet all temperature calculations used for temperature management by dam operations act as if water temperature and temperature behavior are the same day and night.  It has also been stated by the dam operators that “cooler temperature discharge from the dams wouldn’t make any difference” because of “canyon effect.”  Our findings contradict that.
  • Solar radiation (down-bound long wave radiation) is far more important than air temperature in determining river temperatures. Solar radiation warms both air and the water in the river.  That means that shade from canyon walls and riparian vegetation is important in maintaining cooler water in the river.  Air temperature in Redmond is also an important factor in determining the goal for temperature management for dam discharge, yet air temperature has little effect on water temperature.

The second report describes our data and findings from the 2015 water quality study we did in Lake Billy Chinook and in the lower river just below the Pelton-Round Butte Dam Complex. 

Slide2

The Selective Water Withdrawal Tower at Round Butte Dam (the uppermost dam of the three dam complex at Pelton-Round Butte) has intake portals in the top 30 feet of the reservoir, and at 265 feet of depth.  To better understand the water quality effects of Tower operations and selective water withdrawal, we sampled surface water and water at depth in front of the Tower, as well as in the river below the dams.

The data we gathered demonstrated many things, and also raised more questions that we will be attempting to answer through the water quality sampling we started in February of this year. Our results from 2015 shed light on a number of critical factors, including that:

  • Surface water withdrawn from Lake Billy Chinook, for much of the year, consists primarily of water from the Crooked River Arm of the reservoir.
  • Water from the Crooked River Arm is warmer, and of poor water quality (the Crooked River water quality above the reservoir is rated as “poor” by Oregon Department of Environmental Quality). Plus, the water in the Crooked River Arm supports the densest level of algae growth in the reservoir.  In contrast, water from the Metolius River, which, because of its colder temperature constitutes most of the water at the depth of 265’, is of high quality (based on ODEQ data, as well as our own data).

Questions we are hoping to answer in 2016 include (but are not limited to):

  • What is the “nutrient load” entering Lake Billy Chinook from the three tributaries, and when does it get discharged from the dam complex into the lower Deschutes River? Algae in the upper water of the reservoir actually help decrease nutrient levels during summertime growth, but nutrients in surface water discharged in late fall, early winter and spring are not likely attenuated by that algae, and probably contributes significantly to the growth of nuisance algae that has been documented in the lower river.  So we are now tracking nutrient levels at the surface and at depth in the reservoir and below the dams.
  • Is the surface water in the Crooked River Arm of Lake Billy Chinook too toxic for migratory juvenile fish survival during major algae blooms due to high pH, high temperature and/or other variables?
  • Is operation of the dam complex in compliance with the water quality requirements of the Pelton-Round Butte Section 401 Certification under the Clean Water Act and the Federal Energy Regulatory Commission license?

We would also like to announce that we are (finally!) getting some of our raw water quality data posted on our website.  We are open-sourcing the data for all to view or use.  It will take some time to get everything posted, but we will be working on this going forward.

We hope to post updates on our work throughout the year.  So please stay tuned.

Deep and heartfelt thanks to our donors and supporters for making this work possible!

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

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2014 Lower Deschutes River Aquatic Insect Hatch Report – by Greg McMillan

2014 Lower Deschutes River Aquatic Insect Hatch Survey Report

Now Available

Our 2014 Lower Deschutes River Aquatic Insect Hatch Survey by Rick Hafele is now available on our website. Rick, with the help of several guides and experienced fly anglers, compiled over 100 hatch observations in this report.

This is a worthwhile read to understand the hatches on the lower Deschutes. It’s also essential reading to understand the changes in aquatic insect populations and their hatch timing.

The single most startling result noted in the survey is the disappearance of the Antocha crane flies. The participants in this survey aren’t the only ones to note the disappearance of the Antochas. Portland General Electric and The Confederated Tribes of the Warm Springs Reservation, owners/operators of the Pelton-Round Butte Dam complex, hired a natural resources consultant to do a biological survey of the lower Deschutes River. That consultant, in their report, has also failed to find evidence of Antocha crane flies.

How important is the loss of a species of insect in the lower Deschutes? If it’s an indicator of river health, the answer is very important. And we believe the Antochas are an indicator of river health.   We believe that the cause of their demise is the algae that now grows in the splash zone on river rock in the lower Deschutes. It’s in the splash zone that adult crane flies lay their eggs.

Deschutes Crane Flies by John Hazel

Deschutes Crane Flies by John Hazel

This algae, new since the switch to surface water withdrawal at Round Butte Dam, is likely the result of a change in nutrients being discharged from the dam. DRA has reported on this in several previous posts.

Antochas did have value to anglers. During the time of their mating, they were sometimes swept off rocks and made available to feeding fish. The astute angler could be very successful if imitating them at these times. But they had a more important role, and that was as part of the larger food chain of the Deschutes River Canyon. That food chain includes (but is not limited to) fish, birds and bats. The loss of Antochas must not be taken lightly.

Photo by Dave Hughes

Antocha Crane Fly

Special thanks to Rick Hafele for his expertise and diligence in creating this important publication. Also, special thanks to the guides and anglers who made this report possible (John Smeraglio, Sam Sickles, Alex Gonsiewski, David Moskowitz, Steve Pribyl, Steve Light, Evan Unti, Rick Trout, and Damien Nurre).

We Did It! A Report from Greg McMillan

John Hazel watches Larry Marxer measure dissolved oxygen the old-school way.

It was an unfathomable task.  Five sites on 100 miles of river to monitor for 72 hours, continuously, using a variety of complex equipment.  We were challenged by wildfire, river closures, air space closures and severe weather.  Yet our volunteers accomplished the task.

WQ Experts

Steve Pribyl, Jeremiah Bawden, Rick Hafele and Kurt Carpenter

What did we do?  We conducted an extensive water quality monitoring initiative that examined fluctuating temperature, conductivity, turbidity, pH, dissolved oxygen and chlorophyll levels.  This was conducted to look at the magnitude of algae activity in the lowest 100 miles of the Deschutes River.  We monitored conditions from sites at Mecca Flat, Davidson Flat, Oasis Recreation Site, Macks Canyon and Wagonblast.

The Nymph

It’s too early to know what the data will show.  We are still in the process of downloading data from instruments.  Those data, and the data collected via manual instruments, will then undergo statistical analysis.  We’ll be combining those data with the results of the aerial infrared thermal imaging that was completed on July 26.  We’ll look at what species of algae were present during this monitoring period (many samples were collected by Kurt Carpenter from the U.S. Geological Survey Oregon Water Science Center).  

Data Sonde

Tools of the trade – the YSI Data Sonde

Finally, thanks to Quantum Spatial, additional aerial imaging and mapping of the algae growth will take place in early September.  These combined efforts will give us a very good picture of the distribution of the nuisance algae that has appeared in the lower river in the past few years, and the impact it has on water chemistry, and by extension, river ecology.  It will also give powerful clues, or clearly point, to the source(s) of the nutrients and the algae itself.

The process

We measured Dissolved Oxygen (DO) by hand to complement the electronic monitoring devices.

 A special and heartfelt thanks goes out to our volunteers who gave not only of their time, but were willing to be trained on the use of water quality monitoring equipment, and endured some frankly challenging conditions at times.  The volunteers were:

Jeremiah Bawden

Kurt Carpenter

Robert Casey

Joe Combee

Rick Hafele

Bonnie Lamb

Jeff Mann

Larry Marxer

Greg McMillan

Dave Moskowitz

Kate Puddy

Larry Whitney

 

We also owe a special thanks to the Imperial River Company in Maupin, Oregon for allowing us conduct training and organize operations out of their facility, and the Oregon Department of Environmental Quality for the use of water quality monitoring equipment.

Training

Thanks also go out to our donors and other supporters.  Without your help, none of this very important work would be possible.

 

Greg McMillan

President

Director, Science and Conservation

Deschutes River Alliance