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Evaluating the Sensitivity of Projected Reservoir Reliability to the Choice of Climate Projection: A Case Study of Bull Run Watershed, Portland, Oregon

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Nima Fayaz at Syracuse University
Nima Fayaz
Laura E. Condon at The University of Arizona
Laura E. Condon
David G. Chandler
David G. Chandler
David G. Chandler
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Abstract and Figures

Climate change has the potential to alter the quantity and timing of runoff, which may pose significant challenges for reservoir management. One challenge is developing operating policies for an unknown and uncertain future. Here, we develop a suite of ‘optimal’ operating policies for the reservoir system of Portland, Oregon. We assess the sensitivity of projected reservoir reliability to the choice of GCMs and time periods used to develop each of our policies. Results indicate that, while different GCMs and fitting periods produce different optimal operating policies, when those policies are applied across all the other GCM scenarios, the overall projected reliability does not change due to the great variability between simulations. Across the simulations, we note a trend of decreasing reliability in the future which is not sensitive to the choice of GCM or fitting period. This indicates that the projected reliability is dominated by uncertainty in climate projections that cannot be mitigated by tuning operating policies to projected changes.
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Nima Fayaz
1
&Laura E. Condon
2
&David G. Chandler
1
Published online: 15 April 2020
Abstract
Climate change has the potential to alter the quantity and timing of runoff, which may
pose significant challenges for reservoir management. One challenge is developing
operating policies for an unknown and uncertain future. Here, we develop a suite of
‘optimal’operating policies for the reservoir system of Portland, Oregon. We assess the
sensitivity of projected reservoir reliability to the choice of GCMs and time periods used
to develop each of our policies. Results indicate that, while different GCMs and fitting
periods produce different optimal operating policies, when those policies are applied
across all the other GCM scenarios, the overall projected reliability does not change due
to the great variability between simulations. Across the simulations, we note a trend of
decreasing reliability in the future which is not sensitive to the choice of GCM or fitting
period. This indicates that the projected reliability is dominated by uncertainty in climate
projections that cannot be mitigated by tuning operating policies to projected changes.
Keywords Runoff .Operation Polic y .GCMs .Emission Scenario .Reliability
1 Introduction
Projected climate change impacts have far- reaching implications for most aspects of water
resources management, including reservoir operations. (Heino et al. 2009;IPCC2014). In
Water Resources Management (2020) 34:1991–2009
https://doi.org/10.1007/s11269-020-02542-3
*Nima Fayaz
nfayaz@syr.edu
Laura E. Condon
lecondon@email.arizona.edu
David G. Chandler
dgchandl@syr.edu
1
Department of Civil and Environmental Engineering, Syracuse University, Syracuse, NY, USA
2
Department of Hydrology & Atmospheric Sciences, University of Arizona, Tucson, AZ, USA
Evaluating the Sensitivity of Projected Reservoir
Reliability to the Choice of Climate Projection: A Case
Study of Bull Run Watershed, Portland, Oregon
Received: 10 October 2019 /Accepted: 30 March 2020
#Springer Nature B.V. 2020
/
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
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