U.S. Department of the Interior

U.S. Geological Survey

Estimating the efficacy of trout 

management flows using bioeconomic 

and hydropower modeling

Lucas S. Bair, U.S. Geological Survey, Southwest Biological Science Center, Grand Canyon 

Monitoring and Research Center

Pierce Donovan, Colgate University

Matthew N. Reimer, University of California at Davis

Charles B. Yackulic, U.S. Geological Survey, Southwest Biological Science Center, Grand 

Canyon Monitoring and Research Center 

Michael R. Springborn, University of California at Davis

Dominique M. Bain, Excel Energy

Glen Canyon Dam Adaptive Management Program Annual Reporting Meeting 

January 11-12, 2022

U. S. Department of Interior

U.S. Geological Survey
Presentation Background

• Project Element J.1. Predictive Models for Adaptive Management 

– Humpback Chub. Meet humpback chub recovery goals, including 

maintaining a self-sustaining population, spawning habitat, and 

aggregations in the Colorado River and its tributaries below the Glen 

Canyon Dam. 

• Project Element N.1. Hydropower Monitoring and Research 

– Hydropower and Energy. Maintain or increase Glen Canyon Dam electric 

energy generation, load following capability, and ramp rate capability, and 

minimize emissions and costs to the greatest extent practicable, 

consistent with improvement and long-term sustainability of downstream 

resources.

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Humpback Chub (Gila chypha)

3
Cost-effectiveness Analysis

• Comparing the costs of alternative means to

achieve goals set through a political or public

process (Mark Sagoff)

• Cost-effectiveness analysis shifts the focus

from the ends to the means and this is

important where stakeholders have various

world views.

4

Sagoff, Mark. 2009. “Regulatory Review and Cost-Benefit Analysis.” Philosophy 

and Public Policy Quarterly 29 (3–4): 21–26.
5

Bair, L.S., Yackulic, C.B., Springborn, M.R., Reimer, M.N., Bond, C.A., and Coggins, L.G., 2018, Identifying costeffective invasive species control to enhance endangered species populations in the Grand Canyon, USA: 

Biological Conservation, v. 220, p. 12-20, https://doi.org/10.1016/j.biocon.2018.01.032.
Population Viability Analysis (PVA)

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• Develop a bioeconomic model to identify costeffective management strategies for rainbow 

trout, and other alternatives, that achieve 

conservation objectives for the humpback 

chub.

• PVA problems are hard to solve because they 

often involve achieving a population goal over 

many periods with a given level of confidence.
Simulation Based PVA

Juvenile Chub 

Monitoring Reach

Juvenile Chub 

Monitoring Reach

Rainbow Trout Removal

7

Bair, L.S., Yackulic, C.B., Springborn, M.R., Reimer, M.N., Bond, C.A., and Coggins, L.G., 2018, Identifying costeffective invasive species control to enhance endangered species populations in the Grand Canyon, USA: 

Biological Conservation, v. 220, p. 12-20, https://doi.org/10.1016/j.biocon.2018.01.032.
Dynamic Programming Based PVA

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• Identify the cost-minimizing trout control policy 

(removals) that achieves a target population viability.

• The target population viability goal is to maintain 

adult humpback chub abundance above 5,000 at 

least 90 percent of the time over the planning 

horizon.

• This is all subject to the population dynamics of 

rainbow trout and humpback chub. 

Donovan, P., Bair, L.S., Yackulic, C.B., and Springborn, M.R., 2019, Safety in numbers—Cost-effective endangered 

species management for viable populations: Land Economics, v. 95, no. 3, p. 435-453, 

https://doi.org/10.3368/le.95.3.435.
Results of Dynamic Programming Based PVA

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12500

10625

8750

6875

5000

Adult humpback chub abundance

0

900

180027003600

JCM rainbow trout abundance

Management set

Donovan, P., Bair, L.S., Yackulic, C.B., and Springborn, M.R., 2019, Safety in numbers—Cost-effective endangered 

species management for viable populations: Land Economics, v. 95, no. 3, p. 435-453, 

https://doi.org/10.3368/le.95.3.435.
Results of Dynamic Programming Based PVA

10

12500

10625

8750

6875

5000

Adult humpback chub abundance

0

900

180027003600

JCM rainbow trout abundance

Management set

Donovan, P., Bair, L.S., Yackulic, C.B., and Springborn, M.R., 2019, Safety in numbers—Cost-effective endangered 

species management for viable populations: Land Economics, v. 95, no. 3, p. 435-453, 

https://doi.org/10.3368/le.95.3.435.
Trout Management Flows

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U.S. Department of Interior, 2016, Glen Canyon Dam Long-term Experimental and Management Plan final 

Environmental Impact Statement (LTEMP FEIS): U.S. Department of the Interior, Bureau of Reclamation, Upper 

Colorado Region, National Park Service, Intermountain Region, online, http://ltempeis.anl.gov/documents/final-eis/.
Hydropower modeling

• We developed a constrained 

optimization problem to assess 

the short run economic costs of 

environmental constraints on 

hydropower operation.

• The objective of the 

hydropower model is to 

maximize the economic value of 

hydropower over the planning 

horizon subject to reservoir 

levels and operational 

constraints. 

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Harpman, D., 1999, Assessing the Short-Run Economic Cost of Environmental Constraints on 

Hydropower Operations at Glen Canyon Dam: Land Economics, v. 75, no. 3, p. 390-401.
Hydropower Optimization Results

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Revenue

Revenue

Without TMFs With TMFs

Preliminary data, do not cite
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Optimal TMF Policy

Marble Canyon rainbow trout abundance

12500

10625

8750

6875

5000

Adult humpback chub abundance 12500

10625

8750

6875

5000

12500

10625

8750

6875

5000

Preliminary data, do not cite
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Optimal TMF policy – low cost TMF

Marble Canyon rainbow trout abundance

12500

10625

8750

6875

5000

Adult humpback chub abundance 12500

10625

8750

6875

5000

12500

10625

8750

6875

5000

Preliminary data, do not cite
16

Optimal TMF Policy – TMF only

Marble Canyon rainbow trout abundance

12500

10625

8750

6875

5000

Adult humpback chub abundance 12500

10625

8750

6875

5000

12500

10625

8750

6875

5000

Preliminary data, do not cite
17

Optimal TMF Policy – no observation of 

recruitment

Marble Canyon rainbow trout abundance

12500

10625

8750

6875

5000

Adult humpback chub abundance 12500

10625

8750

6875

5000

12500

10625

8750

6875

5000

Preliminary data, do not cite
Conclusions

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• Preliminary results indicate that TMFs are viable (effective and 

economically efficient) control measures at achieving 

humpback chub abundance goals only when rainbow trout 

recruitment in Lees Ferry is high, humpback chub aggregation 

abundance is low, and rainbow trout abundance in Marble 

Canyon and the Juvenile Chub Monitoring (JCM) reach is high. 

• These baseline results are sensitive to the estimated 

economic cost of TMFs (see Project N) relative to rainbow 

trout removal cost and the effectiveness of TMFs specified in 

the LTMEP EIS (U.S. Department of Interior, 2016). 

U.S. Department of Interior, 2016, Glen Canyon Dam Long-term Experimental and Management Plan final 

Environmental Impact Statement (LTEMP FEIS): U.S. Department of the Interior, Bureau of Reclamation, Upper 

Colorado Region, National Park Service, Intermountain Region, online, http://ltempeis.anl.gov/documents/final-eis/.
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