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GLEN CANYON DAM ADAPTIVE MANAGEMENT PROGRAM

TECHNICAL WORK GROUP MEETING

JUNE 16-17, 2021

DAY 1

Start Time: 9:03 AM Pacific Daylight Time (PDT)

Conducting: Seth Shanahan, Technical Work Group (TWG) Chair 

Meeting Recorder: Carliane Johnson, SeaJay Environmental LLC

Welcome and Administrative 

• Introductions and Determination of Quorum (16 members): [Seth Shanahan, Southern Nevada 

Water Authority (SNWA) and TWG Chair] Quorum was reached with 16 TWG members/alternates.

• Adoption of Prior Meeting Minutes: [Paul Harms, State of New Mexico (NM)] One revision noted 

on page 2 of the April meeting minutes is to correct Michelle Garrison’s affiliation to the Colorado 

Water Conservation Board (CWCB). [Seth Shanahan, SNWA/TWG Chair] With that change made, 

the minutes were adopted without objection.

• Next Meeting Date(s): October 13-14, 2021 (webinar).

• Review Action Items, Motions, and Votes Form: The Action Items list was reviewed.

o [Charlie Ferrantelli, State of Wyoming (WY)] Steve Wolff is still listed on the Flow Ad 

Hoc Group (FLAHG) and can be removed.

o [Larry Stevens, Grand Canyon Wildlands Council (GCWC)] The Administrative History 

Ad Hoc Group (AHAHG) will convene prior to the next annual reporting meeting. Dr. 

Paul Hirt is now retired. AHAHG will continue to explore how to engage the system Dr. 

Hirt developed and will include the Glen Canyon Dam Adaptive Management Program 

(GCDAMP) 101 information.

o [Seth Shanahan, SNWA/TWG Chair] The Budget Ad Hoc Group (BAHG) is to start 

considering criteria for prioritizing the Fiscal Year (FY) 2022 budget, which will need to 

be discussed after this TWG meeting.

• Update on Program Funding: [Lee Traynham, Bureau of Reclamation (Reclamation)] 

Reclamation has received full funding for the environmental program for FY21 with funds 

currently being distributed to partners. The President’s FY22 budget was released in May at full 

funding levels ($21.4 million) for GCDAMP and the Endangered Fish Recovery Program. 

• Science Advisors Program Status: [Clarence Fullard, Reclamation] A joint contract is being 

developed for the Science Advisor Program with Reclamation’s Lower Colorado River 

Multispecies Program for a five-year contract awarded by September. 

• Update on Activities Impacted Due to COVID-19 Restrictions: [Mike Moran, Grand Canyon 

Monitoring & Research Center (GCMRC)] No trip cancellations due to COVID since January.

• Update on Monitoring and Research Trips to Occur from Today Until Next Meeting: [Mike 

Moran, GCMRC] See table of all trips for this calendar year through November 2021. The post

overflight trip will ground truth the aerial information. 

TWG Chairperson and Vice-Chairperson Election

[Clarence Fullard, Reclamation] Refer to the TWG’s Operating Procedures for a description of the 

responsibilities of Chair and Vice-Chair positions. The current Chair and Vice-Chair have expressed 
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interest in continuing. [Jessica Neuwerth, Colorado River Board of California (CRBC)] Nominates Seth 

Shanahan as TWG Chairperson, and Michelle Garrison as TWG Vice-Chairperson. [Peggy Roefer, 

Colorado River Commission of Nevada (CRCN) and FLAHG Chair] Seconded those nominees. [Paul 

Harms, NM] Made a motion that the TWG reappoint Seth Shanahan to the position of Chair and 

Michelle Garrison to the position of Vice Chair to the Glen Canyon Dam Technical Work Group for the 

Fiscal Year 2022. [Larry Stevens, GCWC] Seconded. [Seth Shanahan, SNWA/TWG Chair] The nominees 

are approved to their respective positions by consensus.

Panel Discussion –7.48 Million-Acre-Feet (MAF) Release Year in WY2022:

[Seth Shanahan, SNWA/TWG Chair] The BAHG has been discussing this item regarding whether there 

needs to be changes made to budget activities in response low water levels in Lake Powell. [Craig 

Ellsworth, Western Area Power Administration (WAPA) and Budget Ad Hoc Group (BAHG Chair)] This 

is a big issue related to temperature and non-native fish. This is where the program ought to focus. 

[Craig McGinnis, Arizona Department of Water Resources (ADWR)] The last 7.48 MAF release in 2014 

resulted in many effects to native fish and invasive species, so this conversation is indented to consider 

any monitoring that may be needed to identify effects of the next 7.48 MAF year.

Q&A and Discussion

Comments on Additional Items to Add to the List of Effects [Larry Stevens, GCWC] The list of effects 

could include Benthic & Hyporheic Anoxia (BHA) because warm temperatures and low steady flows 

promote that process, particularly because drought conditions might exacerbate BHA farther 

downstream than Lees Ferry. [David Rogowski, Arizona Game and Fish Department (AZGFD)]

Decreasing levels in Lake Mead, increasing habitat in the Colorado River for native fish, increasing river 

temperatures, and the development of Pearce Ferry rapid may have all played a part in non-native fish 

decline. [Melissa Trammell, NPS] Would it be more accurate to say that the razorback sucker decline 

began after 2014 and continued? [Ted Kennedy, GCMRC] Some of the premises in the model are more 

solid than others. 

Comments on Phosphorous [Ted Kennedy, GCMRC] Phosphorous is a primary driver of fish condition.

[Josh Korman, Ecometric] The primary hypothesis in 2014 was that the big rainbow trout biomass could 

not be supported during the drop in prey availability. They are now less abundant and there might not 

be a collapse associated with low prey. It is a different community now, which may affect the 

population. [Seth Shanahan, SNWA/TWG Chair] Is there confidence in the model to predict chub 

numbers based on phosphorous? [Josh Korman, Ecometric] Charles and Bridget have been cautious on

making predictions about forecasting phosphorous levels. The correlations are not great and there are 

no guarantees it is going to be low. [Larry Stevens, GCWC] Conditions are complicated by the 

tributaries. Macrophytic seasonality is much more complicated than was previously known given their 

increase from June through October when downstream temperatures increase. This might be an ideal 

time to get more data on temperature in the ecosystem. [Ted Kennedy, GCMRC] The relationship of 

phosphorous and food base dynamics breaks down farther from the dam. A new citizen science project 

will start this year to sample water during tributary flooding to better understand phosphorus 

contributions.

Comments on Temperature [Ted Kennedy, GCMRC] Regarding temperature, low volume flows with 

slower travel time and less water to warm up, could result in 2-3 degrees warmer water by Diamond 
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Creek. For humpback chub and suckers, more warming is good, but maybe not so good for other fish. 

[Mike Yard, GCMRC] Temperature mediates growth, but growth requires energy (primary production up 

through invertebrate and fish prey). Under low water conditions and without sediment inputs, the water 

will be clearer and there will be an increase in primary productivity. The warmer temperatures may also 

increase bacterial growth from the organics, resulting in a double dose of energy production. 

Comments on Dissolved Oxygen [Josh Korman, Ecometric] There have been low values of dissolved 

oxygen (DO) in recent years, which coincides with warmer temperatures and greater need for food, and 

that makes them metabolically inefficient. It is probably not possible to tease this out. [Ted Kennedy, 

GCMRC] It is probably not possible to make predictions on DO and it is likely independent of release 

volume. [Larry Stevens, GCWC] The concern about DO is that it is not just emergency low DO, but the 

persistently low levels that promote BHA and the production of non-native macrophytes.

Comments on Foodbase and Natural Processes [Ted Kennedy, GCMRC] The pattern is probably related

to drift biomass, which led to reduced spawning. It is likely more related to phosphorus than volume. 

[David Topping, GCMRC] Don't forget that the period July 2013 through June 2014 was the largest Paria 

River sand input year we have had in the last 20 years. One of the key reasons 2014 was so "good" for 

sand was the result of the Paria River activity, not only the low dam releases.

Comments on Humpback Chub in Little Colorado River (LCR) [Ted Kennedy, GCMRC] The low numbers of 

adult fish in 2015 and 2016 were during low flood years. Flooding in the LCR is a strong predictor of chub 

spawning, which has to do with dynamics in the LCR and not what followed a low release year. [Kirk

Young, USFWS] There might be other hypotheses on that. Sampling shows there were higher numbers 

of fish stacked up above the confluence of the LCR after 2015 and 2016. It is not known whether chub 

did not go into the LCR because they did not have the energy to put into spawning or because conditions 

were poor due to the lack of spring runoff, so they did not stay there.

Comments on Humpback Chub in Western Grand Canyon (WGC) [David Rogowski, AZGFD] Don’t think 

the 7.48 MAF release in 2014 had anything to do with what is occurring in the WGC. It seems related to 

the river emerging from the lake as Lake Mead continues to decline resulting in more turbid conditions, 

which humpback chub prefer. [Kirk Young, USFWS] Agrees that temperature is the primary driver in the

WGC, which is probably related to reservoir level. It made habitat available with fewer predators for 

chub to move into and to recruit. [Josh Korman, Ecometric] The river is clearer in WGC due to lower

sediment inputs and lower volume flows, which will increase primary productivity that supports higher 

biomass. Maybe temperature and fewer predators are also part of that, but it is unresolved.

Comments on flannelmouth and bluehead sucker [Larry Stevens, GCWC] Would speckled dace be a 

useful surrogate for humpback chub? Would monitoring them be useful to expand that knowledge? 

[David Rogowski, AZGFD] AZGFD does not find speckled dace in the samples until below River Mile 100 

and then they become more abundant around River Mile 150. 

Comments on razorback sucker [David Rogowski, AZGFD] AZGFD only catches one adult razorback 

sucker every other year. It is not possible to say whether the monitoring trend shown after 2014 was an 

aberration or an actual decline. [Scott VanderKooi, GCMRC] It is hard to make inferences on the data 

given the rarity of razorback sucker.
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[Melissa Trammell, NPS] What is the reason that high sand input from the Paria did not result in high 

phosphorus input, too? In 2014? [David Topping, GCMRC] High sand inputs do correspond with high 

phosphorous inputs. Trying to get those measurements now, but the Paria is not flooding.

Report Out and Recommendation from the Budget Ad Hoc Group for the 

Fiscal Year 2022 Budget and Work Plan

[Mike Moran, GCMRC] [DOWNLOAD] Presentation on GCMRC’s FY 22 Budget Overview. [Clarence 

Fullard, Reclamation] [DOWNLOAD] Presentation on Reclamation’s FY22 Budget and Work Plan. [Peggy 

Roefer, CRCN/FLAHG Chair] [DOWNLOAD] Presentation on BAHG’s recommendations to the TWG on

the FY22 Budget and Work Plan.

Q&A and Discussion

[Jim Strogen, Fly Fishers International (FFI)/Trout Unlimited (TU)] What are the “additional proposal 

detail and completion of compliance requirements” for the Aquatic Vegetation Removal Pilot in Lees 

Ferry (Item #3). Is it realistic to do within this Triennial Work Plan and would another low flow event be 

important to accomplish? [Ken Hyde, NPS-Glen Canyon National Recreation Area (GLCA)] This is a 

reconsideration of the research, and these details are not available. During the 4,000 cubic feet second 

low flow, many places were high and dry, which made brown trout move. The interest is to see whether 

this can be done in other areas that are used by brown trout. Would also have to determine if this 

includes native aquatic plants that only got established because of the dam. [Scott VanderKooi, GCMRC]

There are indications that brown trout take advantage of these habitats. This is an idea to try to 

disadvantage brown trout. It would be important to do this quickly based on data collected in Glen 

Canyon over last few years. Not sure if low flows are needed or if it can be done during normal 

operations during spring maintenance flows. [Kelly Burke, GCWC] Is the urgency also related to the food 

base? [Scott VanderKooi, GCMRC] There has been a change in aquatic vegetation over the years. That is 

something to think about, as well as compliance issues related to removal of natives versus non-natives. 

[Ken Hyde, NPS-GLCA] This is possibly a tool that could be used to knock back significant numbers of 

brown trout. [Ted Kennedy, GCMRC] A robust experimental design could be made by looking at 

untreated and treated reaches. 

[Ben Reeder, Grand Canyon River Guides (GCRG)] What is the name of the study for the High Flow 

Experiment (HFE) down ramping rates? [Ted Kennedy, GCMRC] It was in Project B.6 but that was not 

moved forward because of the larger needs of Project O. This was not part of the BAHG discussions.

[Seth Shanahan, SNWA/TWG Chair] There is space for that in the budget under Experimental Funds. 

[Ben Reeder, GCRG] With respect to Project O.2, the WGC seems to be changing all the time and is one 

of the most dynamic places on the river. Understanding this would be beneficial to the GCDAMP. 

Development of Budget Recommendation to the Adaptive Management 

Work Group (AMWG)

[Cliff Barrett, Utah Municipal Power Agency (UMPA)] Made the following motion of the TWG’s 

recommendation to the AMWG. [Ben Reeder, GCRG] Seconded. [Seth Shanahan, SNWA/TWG Chair]

The motion was passed by consensus.
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The Technical Work Group recommends that the Adaptive Management Work Group recommend for 

approval to the Secretary of the Interior, the Fiscal Year 2022 budget as described in the attached 

worksheets, with the following revisions:

First, the addition of the following prioritized list of Grand Canyon Monitoring and Research Center 

projects to be considered as appropriate sources of funding become available (e.g. Triennial Work Plan 

carryover funds from prior years or through annual review of the Triennial Work Plan or other 

Reclamation considerations).

1. Juvenile Chub Monitoring-West (2023)

2. Additional Trout Recruitment and Growth Dynamics Site (2023)

3. Aquatic Vegetation Removal Pilot in Lees Ferry (202?) (Subject to additional proposal detail and 

completion of compliance requirements.)

4. Decision Analysis - Project O.11 - and Bug Flow Review. (Additional proposal detail requested 

following Science Advisor review.)

5. Aquatic Food Base – Project O.1 (2022)

6. Sediment Mapping Below Diamond Creek - Project O.2 (2022)

Second, the addition of a Dissolved Oxygen Risk Assessment to be completed by Reclamation in 2022 as 

appropriate sources of funding become available.

Update on Hydrology, Operations, and Water Quality Conditions and 

Progress Toward a Low Dissolved Oxygen State-of-Practice Review

[Rick Clayton, Reclamation] [DOWNLOAD] The June mid-month forecast projects 31% (3.367 maf) of 

average annual inflow to Lake Powell in WY 2021. The total release from Glen Canyon Dam for WY 2021 

will be 8.23 maf. The Most Probable release for WY 2022 is 7.48 maf. Due to ongoing transformer 

replacements, only six of eight generating units are expected to be available to make releases from the 

GCD powerplant for much of WY 2021 and WY 2022. [Lee Traynham, Reclamation] [DOWNLOAD]

Presentation on water quality (temperature) at Lake Powell and during dam releases. [Clarence Fullard, 

Reclamation] [DOWNLOAD] Presentation on state-of-practice and risk assessment review on DO, which 

will be accomplished by Reclamation’s Technical Service Center (TSC). 

Q&A and Discussion

[Jim Strogen, FFI/TU] When will information be available to inform decisions at Glen Canyon Dam? Will

this dovetail into the work on temperature control devices? [Clarence Fullard, Reclamation] It will 

probably take at least a few months. An update will be provided on the next TWG call. The initial work 

will inform the rest of the project. [Larry Stevens, GCWC] As temperatures increase, that fosters 

bacterial and other microbial growth, which creates increased risk of human health concerns. Where is 

management’s understanding of that? [Jan Balsom, NPS] The NPS has a new public health officer. There 

have been outbreaks of norovirus in the last couple of weeks. Will follow up with the public health 

officer about this issue. 
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Colorado River System 5-year Projected Future Conditions

[Alan Butler, Reclamation] [DOWNLOAD] Presentation on 5-year projected future conditions. It is a near

certainty that Lake Mead will be below 1090 elevation by next year and below 1045 by 2024. This link

provides additional information on the Alternative Future Hydrology Scenarios. 

Q&A and Discussion

[Shane Capron, WAPA] This is an interesting look out to five years, but it is striking how close the 

different option scenarios were. When WAPA modeled projections out to 20 years, the scenarios get 

“stuck” for 3-5 years when the water levels are at their lowest. [Alan Butler, Reclamation] At least for 

first few years, the similarities in the initial conditions are closer, but then the numbers start to diverge 

in 2025. [Jim Strogen, FFI/TU] Have there been discussions or a plan in place to prolong the operational 

capacity below penstock levels and provide temperature control? [Lee Traynham, Reclamation] The 

focus of discussions has been on preserving Lake Powell elevations above 3490. [Sara Larsen, Upper 

Colorado River Commission (UCRC)] The Upper Colorado River Commission issued a press release about 

the drought operations plan and what kind of releases can be made from Lake Powell within the 

parameters of the Record of Decision. [Rob Billerbeck, NPS] Is it correct that these projections 1) were 

based on the April starting point rather than June; 2) that 1.4 MAF were lost between April and June; 

and 3) did not include water from the Drought Response Operations Agreement (DROA)? When will the

model be updated? [Alan Butler, Reclamation] The first point is correct. Regarding the second point, 

there is an algorithm in the model that tries to move water down from Blue Mesa, Flaming Gorge, 

and/or Navajo. The DROA is to look at conditions in all three of those reservoirs. The model is currently a 

gross approximation of this. The model will likely be updated before August because the conditions have 

changed so much. [Shane Capron, WAPA] Requests that Heather Patno add that to her presentation. 

Rick Clayton to pass this request to Heather. [Kelly Burke, GCWC] How are the state-level and countylevel water management projects integrated into Reclamation’s reservoir protection efforts? [Michelle 

Garrison, CWCB] Reclamation staff work with the local reservoirs to keep track of what is going on. 

Information about the other reservoirs will also be sent to CBRFC’s modeling contractor to include in 

short-term forecasts. Some of these reservoirs in Colorado might only get 5-10% of their water needs 

this year, others are faring better. 

Development of Monitoring Metrics

[Lee Traynham, Reclamation] This effort has been on the tracking list for a long time and the current 

FY21-23 TWP included funding to develop focused and achievable metrics. [Helen Fairley, GCMRC] 

[DOWNLOAD] Presentation on proposed approach and timeline to define metrics for tracking Long-Term 

Experimental and Management Plan (LTEMP) goals. Comments on the draft plan requested by June 30.

Q&A and Discussion

[Kurt Dongoske, Pueblo of Zuni] Concerned about using quantifiable metrics on canyon resources that 

will adversely affect Zuni values or will exclude Zuni understanding to sacred areas. Has Secretary 

Haaland weighed in on this program? It is important to understand how certain communities have been 

disproportionately disadvantaged due to federal environmental compliance requirements. [Helen 

Fairley, GCMRC] This concern has been recognized in GCMRC’s internal discussions and would 

encourage a dialogue to determine how to meet each goal even if it might not include a metric. [Erik 

Stanfield, Navajo Nation] Encourages tribal representatives to discuss this concern. There are new 
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models that include Native American methodologies. There might be common ground to bring a united 

decision to the group. Will send an email to the tribal group to start this discussion. [Leslie James, 

Colorado River Energy Distributors Association (CREDA)] Will speak with Bill Davis to get his 

perspective. 

[Ryan Mann, AZGFD] AZGFD developed performance metrics for rainbow trout in the Lees Ferry Fishery 

Management Plan. Will share this 2015 document and requests that these metrics be included. 

[Seth Shanahan, SNWA/TWG Chair] There is a need to be as simple as possible by using “key metrics”

versus every metric that might be possible. [Helen Fairley, GCMRC] It is a challenge to determine how 

many metrics to capture while recognizing there are many variables that feed into the outcomes.

[Kelly Burke, GCWC] Suggests doing a “test run” on certain goals that have quantifiable values (like 

humpback chub and rainbow trout) compared to others that might not already have measurable goals. 

Perhaps a test run could also include tribal values like compassionate treatment of fish and other 

species. [Helen Fairley, GCMRC] That suggestion is compatible with the approach that will be taken on 

the draft plan, which is to present metrics for several of the goals at the October TWG meeting. 

Public Comment

None.

Meeting adjourned at 3:52 PM PDT
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GLEN CANYON DAM ADAPTIVE MANAGEMENT PROGRAM

TECHNICAL WORK GROUP MEETING

JUNE 16-17, 2021

DAY 2

Day 2: June 17, 2021

Start Time: 9:02 AM PDT

Conducting: Seth Shanahan, TWG Chair

Meeting Recorder: Carliane Johnson, SeaJay Environmental LLC

Welcome and Administrative

[Seth Shanahan, SNWA/TWG Chair] The WAPA discussion on “Additional Information Regarding

Purchase Power Cost Estimates” will be moved to the next TWG meeting. 

• Introductions and Determination of Quorum (16 members): [Seth Shanahan, SNWA/TWG 

Chair] Quorum was reached with at least 16 TWG members or alternates in attendance. 

• Unresolved Issues from Yesterday’s Meeting:

o [Larry Stevens, GCWC] Has concerns about the way the metrics discussion is going and 

will submit comments. Metrics can be chosen, but they may not be the correct ones.

[Seth Shanahan, SNWA/TWG Chair] The TWG will continue to track this as an item to 

address. [Peter Bungart, Hualapai Tribe] There are opportunities to include both 

qualitative and quantitative knowledge into this approach, which should be viewed on 

an equal footing. [Ted Kennedy, GCMRC] An important next step will be to reach out to 

partners, especially tribal members, to get their input on natural processes. 

o [Lee Traynham, Reclamation] TWG nominee packages are moving concurrently with the 

AMWG nominee process. Reclamation will continue to provide updates.

The Influence of Pearce Ferry Rapid as a Fish Barrier

[Ron Kegerries, Bio-West] [DOWNLOAD] Presentation of data about the change in fish species above 

the rapid (natives) compared to below (mostly non-natives). [David Rogowski, AZGFD] [DOWNLOAD]. 

Presentation that shows a significant difference in fish assemblages above and below the rapid.

Q&A and Discussion

[Larry Stevens, GCWC] Carp have been seen swimming upstream of Lava Falls by moving along the 

shoreline. Is the Pearce Ferry rapid different as to why fish are not able to move upstream? [David 

Rogowski, AZGFD] There are no shallow areas along the edges and fish cannot boulder hop from one 

level to another. That is one reason to place antennas upstream of the rapid during different water 

levels. [Ron Kegerries, Bio-West] Still have photographs from the high flow event that need to be 

processed to look at this, which will be incorporated into the final report. [Bill Davis, CREDA] What is the 

significance of this barrier from a long-term standpoint when lake levels are higher? Is it a temporary 

feature when lake levels are low? [David Rogowski, AZGFD] It is assumed that climate change is not 

going to be much different over next 10 years and the rapid is expected to persist through then. [Ron 

Kegerries, Bio-West] It will persist until lake elevations are at 1100 feet and higher. The rapid is also 
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moving west, too. [David Rogowski, AZGFD] As the lake recedes, it is downcutting the riverbed at the 

rapid, so it will not be the same as before when lake levels rise. 

[Seth Shanahan, SNWA/TWG Chair] What is the influence of the 2011 flow as a cue for movement of 

native and non-native fish? [David Rogowski, AZGFD] It depends on when the high flow is. Carp and 

striped bass will move upstream in the springtime, but it is not known whether they can get past that 

barrier. Only found 11 carp and one channel catfish on sampling this past year in the mainstem. They 

used to be numerous. [Ron Kegerries, Bio-West] The high flow seems to spur razorback suckers that 

had sonic tags. As far as non-native fish, there was a tagging study on striped bass that suggested they 

were moving toward the rapid, but no one was really tracking the fish up there. They are using the 

flowing portion of the river, but they may not be effective predators in turbid waters. The barrier 

prevents influx of razorback suckers, too. 

[Jim Strogen, FFI/TU] Has there been any attempt to move native fish upstream of the rapid? [Ron 

Kegerries, Bio-West] The decision whether to stock razorback sucker into the Grand Canyon would need 

to be discussed with the science panel. [Jan Balsom, NPS] This is something we may need to discuss. The 

barrier is great on non-natives, but the natives might need help. [Melissa Trammell, NPS] This is already 

being done on San Juan arm of Lake Powell. It is worth continuing this discussion. 

[Larry Stevens, GCWC] With low lake levels and non-natives prevented from moving upstream, would it 

be effective to place a permanent fish barrier there? [David Rogowski, AZGFD] The only type of barrier 

might be electric and do not see that happening given the flow fluctuations.

[Seth Shanahan, SNWA/TWG Chair] Is the threat of non-natives higher than the benefits to natives if 

lake levels are lower? [David Rogowski, AZGFD] Most fishery biologists would probably agree that it is 

more of a risk to have non-natives move upstream than to increase native exchange. [Brandon Albrecht, 

Bio-West] It is believed that a lot of the young produced from the fish that moved upstream, need to 

get back to Lake Mead to achieve this backwater state that is important for razorback sucker. By 

preventing non-natives from coming up achieves this goal. [Kirk Young, USFWS] The alternative of 

having a non-native dominated system means that the natives would not be successful. It is a tradeoff. 

[Ryan Mann, AZGFD] It seems the rapid has been changing enough in the last few years that it may be 

diminishing as the downcutting occurs. [David Rogowski, AZGFD] That rapid is constantly changing and 

shifting more toward the left bank. It also seems to be downcutting more. It might be completely 

different and might not even exist in 5-10 years. [Larry Stevens, GCWC] What is the future of monitoring 

at the barrier? [David Rogowski, AZGFD] Funding is currently available from USFWS for another year 

and the hope is to extend this for another year beyond that. [Helen Fairley, GCMRC] The characteristic 

of that barrier changed during the spring pulse flow becoming a pure waterfall during lower elevations. 

Informational Updates

Spring Overflight

[Mike Moran, GCMRC] [DOWNLOAD] Presentation on the overflight project, which ended about two 

weeks ago. 
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Q&A and Discussion 

[Jan Balsom, NPS] What is the timeline for processing of the photographs and when they will be 

available? In the past it has taken years. [Mike Moran, GCMRC] Should have delivery of the final 

products by November 2021. [Helen Fairley, GCMRC] In Rick Clayton’s presentation yesterday, there 

was a brief spike in releases. How was that dealt with, how long did it last, and how might it have 

affected downstream flow levels? It could have influenced how the photographs are interpreted. [Ted 

Kennedy, GCMRC] The spike is prominent, but it was only 30 CFS that lasted for 10 hours. It is probably 

not a big concern. [Larry Stevens, GCWC] Have you contemplated putting together a review of past 

aerial overflights given the length of time (4 or more years) that occurs between them? This would 

clarify the need for them. [Mike Moran, GCMRC] Will speak to Joel Sankey about this and present at a 

future TWG. He had prepared a review during the justification for this project. Such a review would 

make clear the value of these overflights and maybe make it possible to schedule them more frequently. 

Spring Disturbance Flows:

[Ted Kennedy, GCMRC; Dave Lytle, Oregon State University (OSU)] [DOWNLOAD] Presentation on the 

March disturbance flow and angler surveys.

Q&A and Discussion 

[Jim Strogen, FFI/TU] Was this helpful for quagga and mud snails? [Ted Kennedy, GCMRC] Lees Ferry

contained lots of quagga mussels and mud snails especially on the upper pulse flows. It is still to be 

determined if this had a population-level effect, but it did lead to mortality of those taxa. [Dave Lytle, 

OSU] The samples were from cobble bars that had just been exposed. Don’t know if there will be a 

difference between species that don’t move around much. [Ben Reeder, GCRG] Could the river become 

unrunnable? [Ted Kennedy, GCMRC] With lower releases over next two years, it may make navigation 

more challenging.

Rainbow and Brown Trout Abundances in Lees Ferry:

[David Rogowski, AZGFD] [DOWNLOAD] Presentation on Lees Ferry fish monitoring in March and creel 

survey data.

Q&A and Discussion:

[Ken Hyde, NPS-GLCA] Was there any effect on rainbow trout spawning that occurred after the spring 

disturbance flow? [David Rogowski, AZGFD] Started to see young-of the-year in the fall. [Seth 

Shanahan, SNWA/TWG Chair] What are thoughts on the influx of kayakers? The guiding community 

would like this to be more controlled because it interferes with launching from the boating ramp. 

Kayakers will also pass right next to fishing lines from the boats, and they are filling up the camping 

spots; however, the guides are making money from hauling. [Jim Strogen, FFI/TU] Many kayakers are 

not using lifejackets. [David Rogowski, AZGFD] They get rescued often. [Cliff Barrett, UMPA] One chart 

showed population of brown trout increasing in the Lees Ferry. What is happening in Lower Colorado 

River? [David Rogowski, AZGFD] They are at the lowest numbers ever seen. [Helen Fairley, GCMRC] Any 

insights into the disparity between guided and non-guided incentivized harvest program? [David 

Rogowski, AZGFD] Yes, it has always been a catch and release fishery and would like to catch the biggest 

fish, which are the brown trout. They discourage the harvest of brown trout. [Ben Reeder, GCRG] Heard 

from one fly fishing guide from Northern Arizona who was very anti-harvesting and the high flow 

experiments. [Ken Hyde, NPS-GLCA] The guides during the whole planning effort from 2017-2109 made 
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it clear that they did not want to change. Can only remind them that the program is available and that 

heavier-handed tools will be needed if the program is not successful. 

Incentivized Harvest Program Implementation:

[Ken Hyde, NPS-GLCA] [DOWNLOAD] Presentation showing results from the “Brown Trout Bonanza”. 

Q&A and Discussion

[Leslie James, Colorado River Energy Distributors Association (CREDA)] The National Water Resources 

Association is planning its annual meeting for Scottsdale in mid-November. Can provide information for 

those coming into town. [Ken Hyde, NPS-GLCA] Maybe the angler from Michigan who did so well during 

April could be the first one to make a video. Only one fish was turned in that was over 24 inches even 

though the guides have said they have tossed some back that were over 30 inches, which are the best 

spawners. We might have to figure out how to incentivize for these larger fish. [Bill Davis, CREDA] Have 

any comparisons been made with Dave Rogowski’s observations on brown trout to see if the program is 

having any effect? [Ken Hyde, NPS-GLCA] This is just the first year. The interest has been focused on 

getting higher participation. At the end of the year, the program will be reassessed to see if it has had 

any impact on rainbow trout recruitment rates. [Scott VanderKooi, GCMRC] There will be a trip at the 

end of June in Glen Canyon that is part of the trout recruitment monitoring that will help to understand 

what is happening. The mark-recapture data from GCMRC will also help determine if there have been 

any changes in the population. [Seth Shanahan, SNWA/TWG Chair] As GCMRC researchers present their 

data from those trips, they should include a comparison table to see how things match up. [Erik Skeie, 

State of Colorado] Did not see much signage information about the incentivized harvest program. It was 

only at one kiosk. It might be helpful to place information at the Lees Ferry campground and the Paria 

Beach parking lot. [Ken Hyde, NPS-GLCA] Two more kiosks were finished in March; one of them was 

near Paria Beach. Brown trout numbers still seem to be low with the walk-in fishers. [Jim Strogen, 

FFI/TU] What are you doing in local areas to generate interest? [Ken Hyde, NPS-GLCA] Did radio 

interviews, newspaper press releases, and talking to people. There are only a couple of boat ramps in 

the water and the traffic is picking up, which should generate more interest. [Kirk Young, USFWS] What 

were the harvest objectives? It reinforces the need to continue looking at all the possible tools. [Ken 

Hyde, NPS-GLCA] It was a guesstimate of about 200-250 fish per month, and more PIT tags needed to be 

turned in to develop the model. Current numbers are about a quarter of that. The Bonanza showed that 

it takes time for anglers to figure out where brown trout can be found. [Clarence Fullard, Reclamation]

What is the timeline to determine how many fish need to be harvested to get an effect? [Ken Hyde, 

NPS-GLCA] The funding package was for three years. Will be looking at data after this first year to 

determine which bonuses helped the most or if other things can be tried. Still thinking a couple fishing 

tournaments could really open this up. It is the tail end of COVID in Arizona so that will not happen until 

fall or next spring.

Biological Opinion Conservation Measures and Triggers:

[Kerri Pedersen, Reclamation] The final rule for listing the Kanab Ambersnail is going to be published in 

the Federal Register on June 18, 2021. The rule will go into effect 30 days after. Regarding humpback 

chub triggers, there are a series of threshold levels for adults and sub-adults. A Tier 1 trigger was met 

meaning additional conservation actions are required to reverse the decline to prevent the need for Tier 

2 mechanical removal actions. Reclamation is working with USFWS to develop a plan that is a balance of 

adapting to current conditions within the constraints of the biological opinion. The document on the 
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triggers will also be undergoing a 5-year review this summer. Ideas or comments should be sent to Kerri 

or Kirk. [Kirk Young, USFWS] The Tier 1 conservation actions include collecting and moving larval fish. 

Because of the lack of spring runoff in the LCR, the year 1 humpback chub were not as abundant as 

expected but were able to translocate 533 year-one fish to Chute Falls. Did not find any humpback chub

larvae although it is certain they were there. 

Q&A and Discussion

[Jim Strogen, FFI/TU] Any information from young-of-year at the translocation sites and to use these 

sites for future translocation? [Kirk Young, USFWS] See some recruitment above Havasu Falls but it is 

not a lot. It may not be enough to supply extra fish for the translocations. [Jim Strogen, FFI/TU] What is 

the format and process to provide comments? [Kirk Young, USFWS] Will accept comments in any 

format, especially any ideas on conservation actions that are not being considered or about the trigger 

document that can lead to building a more effective tool to reduce effects on humpback chub.

Discussion About Possible Experimental and Management Actions That 

May be Implemented in the Next 12 Months and Any Budgeting Issues

[Clarence Fullard, Reclamation; and Mike Moran, GCMRC] [DOWNLOAD] Presentation of the LTEMP 

experiments that may be implemented in next 12 months; update on current sediment conditions in the 

river, trout management flows (TMF), and macroinvertebrate flows (“bug flows”). Reclamation may

have a draft TMF white paper by end of this year and GCMRC is preparing a synthesis of bug flow data 

that is expected to be delivered by October. 

Q&A and discussion

[Seth Shanahan, SNWA/TWG Chair] Can the TMF white paper be presented in October? [Clarence 

Fullard, Reclamation] Not sure that can be promised, but will provide an update on the white paper 

status at the next TWG.

Monitoring Native Fish and Invasive Aquatic Species System-wide

[David Rogowski, AZGFD] [DOWNLOAD] Presentation on systemwide monitoring of fish from Lees Ferry 

to Pearce Ferry rapid.

Q&A and Discussion

[Jan Balsom, NPS] Do you see brown trout migrating beyond upper Marble Canyon? [David Rogowski, 

AZGFD] Still find them throughout Marble Canyon, but only catching one or two fish. Brown trout does 

not tend to migrate like other salmonids do. [Jim Strogen, FFI/TU] Any word on numbers or changes of 

rainbows or brown trout at the confluence of LCR? [David Rogowski, AZGFD] This is usually presented at 

the Annual Reporting Meeting. There was probably no change but only 17 brown trout and a couple of 

rainbow trout were caught just below there, which was like past years. [Scott VanderKooi, GCMRC] Do 

not recall rainbow trout numbers increasing at the juvenile chub monitoring site, which is at the LCR 

confluence. Regarding the earlier presentation about Pearce Ferry as a barrier, it appears that the drop 

in non-natives preceded the development of the rapid. [David Rogowski, AZGFD] The rapid is one part

of the theory about the decline. The water is more still and warmer upstream of Pearce Ferry as Lake 

Mead declines. This created favorable reproductive (backwater) areas for common carp and channel 

catfish. [Scott VanderKooi, GCMRC] This shift to native species in the canyon is a great story and likely 
Page 13 of 17

the result of a few things. It is opposite of what is being seen in almost all other Western rivers. [Seth 

Shanahan, SNWA/TWG Chair] Are you exploring models to explain these responses? [David Rogowski, 

AZGFD] Working on a paper now to do that. The effect appears to be caused by a variety of factors, 

which are difficult to tie together with no definitive answers. 

Discussion about Invasive Nonnative Fish Passage and Temperature 

Control Methods at Glen Canyon Dam

[Clarence Fullard, Reclamation] [DOWNLOAD] Presentation on recent progress made on temperature 

control and fish passage at Glen Canyon Dam. 

TWG Member Discussion: 

[Seth Shanahan, SNWA/TWG Chair] How can these big ideas be pursued while balancing the costs and 

the reasons for doing them? [Bill Davis, CREDA] This issue has been raised since the 1980s. Until the

remaining biological questions can be answered, nothing can be designed. In 1989, the idea was to 

warm up the water to help natives, but that did not work. [Ted Kennedy, GCMRC] The objectives have 

shifted since the 1970s. It was thought this was a cold-water system. Then the concepts of climate 

change and the long-term drought shifted those views of the future. Reclamation’s projections about 

Lake Powell, temperature, and basin warming are accurate. The objectives to disadvantage non-native 

fauna need to be done in a warm-water system. [Bill Davis, CREDA] There needs to be consensus from 

the biologists on whether we want a cold-water system and then move forward on the design. [Ted 

Kennedy, GCMRC] Would like to know what are their concerns? [Larry Stevens, GCWC] The 

temperature range regarding a warm versus cool-water system is significantly different in design. Agrees 

with Bill that we need to understand what it is that we are trying to get at? [David Ward, GCMRC] The 

problem is a need for flexibility to do both regarding temperature because there could be bad outcomes 

if natural conditions create either scenario. [Melissa Trammell, NPS] There are definitely concerns

about warmer water, and there needs to be flexibility for both cool and warm options; otherwise, the 

system is going to move out of its sweet spot for native fish. [Seth Shanahan, SNWA/TWG Chair] How 

important is it to have a surveillance program and for our capacity to rapidly respond to a concern? [Bill 

Davis, CREDA] Maybe it is time to review this again with all the changes over the past 20-30 years. 

Perhaps the experts could convene a workshop on what needs to be done on the river. [Ken Hyde, NPSGLCA] This was covered in the NPS’s recent non-native aquatic planning efforts. Many of these things 

were not in place in 2014. Managers have more options now. [Scott VanderKooi, GCMRC] What is being 

asked going forward? Is there a need for a workshop? GCMRC is always interested in improving its 

methods and meeting its partners’ needs. [Seth Shanahan, SNWA/TWG Chair] There is no request yet, 

but Bill is suggesting a workshop. [Scott VanderKooi, GCMRC] In terms of temperature control, this has 

been an issue for decades and where to go for the future is something that management has to decide, 

not the scientists. [Seth Shanahan, SNWA/TWG Chair] The risk has increased from additional habitat 

warming. What are the thresholds on when to determine to take action? [David Ward, GCMRC]

Monitoring programs for early detection are good, but biologists are concerned about not having rapid 

response methods. The temperature tools would be helpful for this. [Ken Hyde, NPS-GLCA] In another 

25 or 30 feet, a lot more fish are going to come through the penstock especially green sunfish and 

smallmouth bass. [Jim Strogen, FFI/TU] Temperature control devices and fish passage efforts are 

preventative, while the NPS environmental assessment on brown trout are reactive. We need to be 

more preventive than reactive. [Bill Davis, CREDA] The history of the river system before the dam was 
Page 14 of 17

90% channel catfish. [Seth Shanahan, SNWA/TWG Chair] There is the longer-term preventative path

(because it takes a long time to get things in place), but we have shorter terms such as next year with 

lower levels in Lake Powell. What if the monitoring program found 3 walleye? Would that be enough to 

respond? [David Ward, GCMRC] That would not be enough as 3 walleye are found all the time; there 

would be a problem if 300 walleye were found. Pretty informed decisions can be made with the 

monitoring data. The real crux is what to do about it. [Ken Hyde, NPS-GLCA] NPS can respond to shortterm concerns, but it does not have responses to chronic, long-term issues, which is probably not 

feasible given the costs that would be required. An expert panel or workshop might be helpful. Also still 

need to know temporal temperatures that are beneficial to non-natives of concern, and to look at tools 

that would be able to cool water. The bypass is the only one that is probably currently feasible. All these 

tools need to be assessed. [Melissa Trammell, NPS] A cooling temperature control device is preferred. 

[Ryan Mann, AZGFD] In addition to temperature control devices for non-natives, there is also 

management of the rainbow trout fishery and future projections are pushing the boundaries of 

allowable habitat for that fishery to exist. [Larry Stevens, GCWC] In relation to this five-year planning 

effort, it is not known whether the minimum pool stage will be met in Lake Powell. In this case, the river 

would probably return to a pre-dam temperature regime, which was at or exceeded 89 degrees at Lees 

Ferry during low flow summers. This needs to be included in the worst-case scenarios. [Kirk Young, 

USFWS] If the water has to go through the by-pass tubes, the opposite might be true, making this a coldwater system. [Seth Shanahan, SNWA/TWG Chair] Would like the TWG to consider the workshop idea 

between now and October. 

Discussion of Emerging Issues, Updates on Items of Interest That Are in 

Consideration for Implementation Before Next TWG Meeting, and 

Request for Agenda Items for Next Meeting

[Shane Capron, WAPA] Given the new study, WAPA expects $72 million in purchase power costs in 

water year 2021, and with 7.48 MAF in water year 2022, it is expected to be $98 million with possibly 

the same in 2023. Looking at $77 million in the Basin Fund for FY21. Prices keep getting higher. Brian 

Sadler will give a presentation on this information at the August AMWG meeting.

[Larry Stevens, GCWC] Downstream waters have been clear because of a lack of monsoon rains. Where 

are we with understanding caddisflies at the lower end and has there been any assessment of the

quagga mussel invasion in the main river? [Ted Kennedy, GCMRC] GCMRC is working on caddisflies to 

try to resolve whether those increases were because of bug flows or other factors such as water clarity. 

GCMRC is doing monitoring in Bright Angel Creek, but that is the only tributary with funding available to 

look at invertebrates in the side streams. There had been a proposal in the TWP throughout the canyon, 

but that did not make the final cut. Dave Lytle participated in a river trip in April in which his lab 

collected samples for e-DNA analysis. They sampled throughout the mainstem, near the mouths of the 

tributaries and a kilometer upstream. He plans to focus on insect taxa and may also be looking at all the 

invertebrates, in general. He is leveraging funding with the Department of Defense. This could give 

insights as to the extent of quagga mussel in the side streams. [Larry Stevens, GCWC] There is interest 

by GCWC in this. [Seth Shanahan, SNWA/TWG Chair] The hydrologic forecasting community does a lot 

of work on this and greater coordination with them could be useful to feed into the ecological models.
Page 15 of 17

[Leslie James, CREDA] As a result of the hydrology and market prices, WAPA is also starting a rate 

review process. This might be posted soon in the Federal Register. Any peak use customers are urged to 

defer anything that is not considered essential that could impact the Basin Fund. Going into the worst 

month of the year for utilities. The numbers on the purchase power amounts and impacts to Basin Fund 

are uncommon and extreme. Everyone is looking closely at how to mitigate those impacts. 

[Ken Hyde, NPS-GLCA] With the historic low water levels, the Glen Canyon NPS management team is 

doing everything possible to keep two ramps out of 11 open to the water. It is important to the local 

economies and to the economies of Utah and Arizona.

[Kirk Young, USFWS] We should discuss how the GCDAMP will deal with the effects of climate change. 

Modeling projections for the Southwest is that it will become hotter and more arid, which means less 

precipitation. Flexibility to release water from the dam could be seriously compromised in the future

and how to manage downstream resources. Perhaps scientists can be invited at the next Annual 

Reporting Meeting. [Seth Shanahan, SNWA/TWG Chair] What was the planning analysis done during 

the LTEMP? [Rob Billerbeck, NPS] Mike Runge and Jim Prairie made sure there were a series of drier 

climate change runs in the model to ensure that the one chosen performed the best under both regular 

hydrology scenarios and drier climate change conditions. They could give a more detailed explanation. 

[Scott VanderKooi, GCMRC] There was a recent paper by Kim Dibble and Charles Yackulic that did many 

of those things that addressed reservoir projections and fish impacts. [Peter Bungart, Hualapai Tribe]

Some of the underpinnings of LTEMP might be stale given these current projected changes. They might 

need to be re-evaluated.

[Kurt Dongoske, Pueblo of Zuni] Climate change will have a disproportionate impact on indigenous

communities. How will the federal government recognize this fact? 

[Ben Reeder, GCRG] Suggests a presentation by the Colorado Plateau Foundation whose mission is to 

protect the lands and waters of the Colorado Plateau. They provide funding for tribal initiatives. 

[Craig McGinnis, ADWR] Suggests continuing the 7.48 MAF discussion because that had been cut short. 

[Helen Fairley, GCMRC] Maybe there needs to be a special TWG meeting with more discussion and 

fewer presentations? [Seth Shanahan, SNWA/TWG Chair] Perhaps there could be a 2-4-hour 

informational discussion session by webinar on a topic. These would not be formal TWG meetings. 

[Several others agreed to this idea; no one objected.] [Mike Moran, GCMRC] Maybe an Informational 

Sharing Ad Hoc group could be created, and then someone could take the lead on this. [Michelle 

Garrison, CWCB] If there are more workshops, should they occur just before a TWG meeting or be

spread out from the TWG schedule? [Leslie James, CREDA] It is very hard to remain engaged when there 

are two days of the TWG meeting followed by the informational discussion.

Public Comment

[Alicyn Gitlin, Sierra Club - Grand Canyon Chapter] The Sierra Club supports the comment to reanalyze 

LTEMP in light of climate change. The Sierra Club had made many suggestions on LTEMP that have since 

come up from other groups, but there has never been a response as to why the Sierra Club’s suggestions

could not be analyzed (i.e., assess other alternatives, consider more flexibility for spring or summer high 

flows, slower ramp downs, consider effects of a climate future). Would love to see that document reanalyzed.
Page 16 of 17

Adjourned at 2:50 PM PDT

Attendees 

TWG Members and Alternates 

 

Jan Balsom, NPS-GRCA Leslie James, CREDA (Alternate)

Cliff Barrett, UMPA Jakob Maase, Hopi Tribe

Peter Bungart, Hualapai Tribe (Alternate) Ryan Mann, AZGFD

Kelly Burke, GCWC (Alternate) Craig McGinnis, ADWR (Alternate)

Shane Capron, WAPA Jessica Neuwerth, CRBC

William "Bill" Davis, CREDA Bill Persons, FFI/TU

Kurt Dongoske, Pueblo of Zuni Ben Reeder, GCRG

Craig Ellsworth, WAPA (Alternate) Peggy Roefer, CRCN (Alternate)

Charlie Ferrantelli, State of Wyoming (Alternate) David Rogowski, AZGFD (Alternate)

Michelle Garrison, CWCB (Vice-chair) Seth Shanahan, TWG Chair and SNWA

Jessica Gwinn, USFWS (Alternate) Larry Stevens, GCWC

Paul Harms, State of New Mexico Jim Strogen, FFI/TU

Ken Hyde, NPS-GLCA Kirk Young, USFWS

USGS/GCMRC Staff 

 

Lucas Bair David Topping

Helen Fairley Scott VanderKooi

Ted Kennedy Mark Wimer

Michael Moran David Ward

Emily Palmquist Michael Yard

Reclamation Staff 

 

Tara Ashby Zachary Nelson

Alan Butler Kerri Pedersen

Kathy Callister Ernie Rheaume

Rick Clayton Lee Traynham

Clarence Fullard

Interested Persons 

 

David Alberg, NPS McKenna Murray, State of Utah

Brandon Albrecht, Bio-West Amy Ostdiek, State of Colorado

Richard Begay, Navajo Nation Stanley Palmer, Salt Lake Community College

Rob Billerbeck, NPS Justin Pattison, NPS

Sarah Creachbaum, NPS Mary Plumb, NPS

Kevin Dahl, NPCA Sara Price, CRCN

Fred Daniel, Fireflies.ai Shana Rapoport, CRBC

Derek Fryer, WAPA Ted Rampton (no affiliation given)

Alicyn Gitlin, Sierra Club Matt Rice, American Rivers

Carliane Johnson, SeaJay Environmental Gene Seagle, NPS

Kristen Johnson, ADWR William "Billy" Shott, NPS
Page 17 of 17

John Jordan, FFI/TU Erik Skeie, State of Colorado

Ron Kegerries, Bio-West Todd Smith, NPS

Michelle Kerns, NPS Erik Stanfield, Navajo Nation 

Josh Korman, Ecometric Gary Tallman, Northern Arizona University

Angelika Kurthen, Oregon State University Brenda Todd, NPS

Sara Larsen, Upper Colorado River Commission Melissa Trammel, NPS

Dave Lytle, Oregon State University Jerry Wilhite, WAPA

Kevin McAbee, USFWS Jonathan Winters, NPS

Scott McGettigan, State of Utah Mark Wondzell, NPS

Betsy Morgan, State of Utah

Abbreviations 

 

ADWR - Arizona Department of Water Resources GCWC - Grand Canyon Wildlands Council

AZGFD - Arizona Game and Fish Department GLCA - Glen Canyon National Recreation Area

AHAHG - Administrative History Ad Hoc Group HFE - High Flow Experiment

AMWG - Adaptive Management Work Group LCR - Little Colorado River

BAHG - Budget Ad Hoc Group LTEMP - Long-Term Experimental and Management 

Plan

BHA - Benthic & Hyporheic Anoxia MAF - million-acre-feet

CFS - cubic feet per second NPS - National Park Service

CRBC - Colorado River Board of California PDT - Pacific Daylight Time

CREDA - Colorado River Energy Distributors Association PIT - passive integrated transponder 

CRCN - Colorado River Commission of Nevada Reclamation - Bureau of Reclamation

CWCB - Colorado Water Conservation Board SNWA - Southern Nevada Water Authority

DO - dissolved oxygen TSC - Technical Service Center

DROA - Drought Response Operations Agreement TU - Trout Unlimited

FFI - Fly Fishers International TWG - GCDAMP Technical Work Group

FLAHG - Flow Ad Hoc Group UCRC - Upper Colorado River Commission

FY - fiscal year UMPA - Utah Municipal Power Agency

GCDAMP - Glen Canyon Dam Adaptive Management 

Program USFWS - United States Fish & Wildlife Service

GCMRC - Grand Canyon Monitoring & Research Center USGS - United States Geological Survey

GCNP - Grand Canyon National Park WAPA - Western Area Power Administration

GCRG - Grand Canyon River Guides WGC - Western Grand Canyon