Measurement of Lake Roosevelt Biota in Relation to Reservoir Operations : Appendices 1992.

This paper presents the Risk Informed Decision-making Framework and software tool we developed that formally account for flood risk and uncertainty in reservoir operations. The framework and the software tool are intended for practical use by reservoir operations planners to manage flooding events. We present a robust and comprehensive approach that accounts for a multitude of flood risks and their impacts, and that enables its users to identify those alternative reservoir operating plans that formally adopt a state-of-the-art risk informed decision-making framework. Solidly grounded in and closely follows a well-structured planning process, the framework augments existing planning processes and information flows that incorporates specific techniques and methods from probabilistic risk analysis (PRA) and Multi-criteria Decision Analysis techniques (MCDA). Seven major hydropower companies and agencies in North America and Europe sponsored the development of the framework and the decision support tool. We present the results of a case study to illustrate the framework and the software system. We show that numerous advantages can be achieved using such tools over currently used approaches and that in the case of risky and high-impact processes, such as in the management of potentially high-consequence facilities such as storage reservoirs, management by a human operator is essential.

Download Full-text

Process-based model of fish incubation survival for designing reservoir operations: a case study for Sacramento River winter-run Chinook salmon

10.1101/2020.08.26.269357 ◽

2020 ◽

Author(s):

James J. Anderson ◽

W. Nicholas Beer ◽

Joshua A. Israel ◽

Sheila Greene

Keyword(s):

Real Time ◽

Chinook Salmon ◽

Oncorhynchus Tshawytscha ◽

Cold Water ◽

Climatic Variability ◽

Sacramento River ◽

Reservoir Operations ◽

Regulated Rivers ◽

Egg Hatching ◽

Critical Window

AbstractAllocating reservoir flows to meet societal and ecosystem needs under increasing demands for water and increasing climatic variability presents challenges to resource managers. Often, regulated rivers have been operated to meet flow and temperature compliance points that mimic historical patterns. Because it is difficult to assess if this approach is efficient or equitable, new more process-based approaches to regulation are being advanced. This paper describes such an approach with a model of egg incubation survival of Sacramento River winter-run Chinook salmon (SRWRC, Oncorhynchus tshawytscha). Thermal mortality only occurs in a critical window around egg hatching when the embryo is most sensitive to temperature stress. The duration of the critical window has significant implications for Shasta Reservoir operations that are designed to control temperature during SRWRC incubation. Previous operations sought to maintain a low temperature over the entire incubation period. However, model analysis suggests that targeting cold water directly to the critical egg hatching stage provides higher survival while requiring less cold water resources. The calibrated model is publicly accessible through a web interface connected to real-time river and fish databases and a river temperature forecast model. The system is an example of the next step of river management that integrates databases with hydrological and process-based biological models for real-time analysis and for forecasting effects of river operations on the environment.

Download Full-text