Balancing Ecological and Energy Needs in California's Water Resources through FlowPywr: A Decision Support System for Integrating Hydropower Operations and Environmental Flows under Climate Change
The Regents of the University of California, Merced
Recipient
Merced, CA
Recipient Location
Senate District
27th
Assembly District
Active
Project Status
Project Update
Work on updating the climate change data and scenarios for the CenSierraPywr model are continuing and are expected to be complete June, 2026. Model validation will follow shortly after. The researchers are also developing runoff data for input into the model. This has involved sourcing of natural flow data and investigating data discrepancies to ensure accurate input data for Pywr model. In addition, work has started on identifying what policies and regulations are influencing environmental flows and how those policies get implemented at an operational level and how they may enhance or hinder environmental flows. Over the course of 2025, the research team developed model capacity for pricing signals within the energy demand module and worked to enable integration of this module into the larger modeling framework. The effort is on track for completion within the term of the agreement
The Issue
The central challenge this project addresses is the need for a replicable decision support system capable of providing a balance between hydropower generation and ecosystem preservation. As climate change intensifies and the demands on water resources escalate, there is a pressing need to address the existing gaps in knowledge and the absence of an integrated framework that captures the interdependencies between renewable energy production and environmental conservation. By creating a robust, data-driven decision support system, we seek to facilitate sustainable water management practices that account for the growing need for clean energy and the protection of vital ecosystems, ultimately enabling more efficient trade-offs and environmentally sustainable solutions.
Project Innovation
The Recipient has developed a framework for a comprehensive and replicable decision support system that integrates advanced water-energy modeling techniques, stakeholder engagement, and interdisciplinary expertise to inform FERC relicensing processes. This framework utilizes the CenSierraPywr model based on Pywr, which incorporates environmental flows, hydropower optimization, and climate change impacts using climate realizations from the Coupled Model Intercomparison Project Phase 6 (CMIP6) to provide a holistic understanding of the complex water-energy-ecosystem nexus. By employing stakeholder- informed functional flow regimes, and energy grid integration, the decision support system will enable informed planning and management of water resources, ensuring sustainable hydropower operations that simultaneously minimize negative impacts on ecosystems. This approach will provide an innovative environmental assessment and modeling tool for FERC relicensing, addressing the challenges posed by climate change, increasing water demands, and the need for sustainable energy solutions.
Project Goals
Project Benefits
This Agreement will result in ratepayer benefits in several ways by facilitating better integration of hydropower into California's zero-carbon generation portfolio while simultaneously supporting and enhancing downstream ecosystem needs.
Consumer Appeal
Lower costs - Decision support tools developed in the project will enable efficient water and energy resource management, reduce costs and increase affordability for ratepayers in California.
Economic development -
Environmental public health - The project will promote environmental sustainability by integrating environmental flow strategies into the decision support tools. The project will ensure a balance between ecosystem needs and human activities.
Key Project Members
Josh Viers
Subrecipients
University of California, Irvine
American Rivers
