Finding middle ground: Flow regimes designed for salmon and energy value

Henriette I. Jager, Rocio Uria-Martinez

Research output: Contribution to journalArticlepeer-review

Abstract

In regulated rivers, shaping seasonal flows to recover species at risk depends on understanding when to expect conflicts with competing water users and when their interests are aligned. Multi-objective optimization can be used to reveal such conflicts and commonalities. When species are involved, multi-objective optimization is challenged by the need to simulate complex species responses to flow regimes. Previously, we addressed that challenge by developing a simplified salmon model (Quantus) that defines cohorts of salmon by the river section and time in which they were spawned. Salmon in these space-time cohorts are tracked from the time redds (nests) are constructed until the cohort exits the tributary en route to the ocean. In this study, we modeled seasonal patterns in energy value and developed a Pareto-optimal frontier of seasonal flow patterns to maximize in-river salmon survival and hydropower value. Candidate flow regimes were characterized by two pulse flows varying in magnitude, timing, and duration and constrained by a total annual flow near the historical median. Our analysis revealed times when economic and salmon objectives were aligned and times when they differed. Pulse flows that favored higher energy value were timed to meet demand during extreme temperatures. Both salmon and hydropower objectives produced optimal flow regimes with pulse flows in early summer, but only solutions favoring hydropower value included high flows in mid-winter. Solutions favoring higher age-0 salmon survival provided an extended pulse flow in late winter/early spring, which suggests that access to productive floodplain habitat allowed faster growth and earlier out-migration and reduced the need for higher temperature-moderating flows later in spring. Minimum flows were also higher among solutions favoring salmon over energy. The tools used to produce these results can help to design simplified seasonal flow regimes by revealing compromise solutions that satisfy both fish and energy producers and highlighting when potential conflicts are likely.

Original languageEnglish
Article number100183
JournalWater Biology and Security
Volume2
Issue number3
DOIs
StatePublished - Jul 2023

Funding

This research, conducted by Oak Ridge National Laboratory (ORNL), was supported by the US Department of Energy's (DOE) Energy Efficiency and Renewable Energy Office, Wind and Water Power Technologies Program. ORNL is managed by UT-Battelle, LLC under Contract No. DE-AC05-00OR22725 with the DOE. The publisher, by accepting the article for publication, acknowledges that the U.S. Government retains a non-exclusive, paid-up, irrevocable, world-wide license to publish or reproduce the published form of this manuscript, or allow others to do so, for U.S. Government purposes. The DOE will provide public access to these results of federally sponsored research in accordance with the DOE Public Access Plan (http://energy.gov/downloads/doe-public-access-plan). This research, conducted by Oak Ridge National Laboratory (ORNL), was supported by the US Department of Energy's (DOE) Energy Efficiency and Renewable Energy Office , Wind and Water Power Technologies Program. ORNL is managed by UT-Battelle, LLC under Contract No. DE-AC05-00OR22725 with the DOE. The publisher, by accepting the article for publication, acknowledges that the U.S. Government retains a non-exclusive, paid-up, irrevocable, world-wide license to publish or reproduce the published form of this manuscript, or allow others to do so, for U.S. Government purposes. The DOE will provide public access to these results of federally sponsored research in accordance with the DOE Public Access Plan ( http://energy.gov/downloads/doe-public-access-plan ).

FundersFunder number
DOE Public Access Plan
U.S. Government
U.S. Department of Energy
Office of Energy Efficiency and Renewable Energy
Oak Ridge National Laboratory
UT-BattelleDE-AC05-00OR22725

    Keywords

    • Electricity price model
    • Environmental flows
    • Fall chinook salmon
    • Genetic algorithm
    • Multi-objective
    • Optimization
    • Pareto optimal frontier
    • Pulse flows
    • Reservoir release schedule

    Fingerprint

    Dive into the research topics of 'Finding middle ground: Flow regimes designed for salmon and energy value'. Together they form a unique fingerprint.

    Cite this