Unlocking Hydropower Potential from Environmental Flows for Energy-Water Resilience

This white paper examines how mandated environmental flow (E-flow) releases at hydropower dams can be leveraged to generate renewable energy while maintaining ecological integrity. Environmental flows sustain aquatic ecosystems but often bypass turbines, representing lost generation potential. This paper explores technical, regulatory, and operational challenges, including aging infrastructure, misaligned flow regimes, economic barriers, and limited data integration. Near-term opportunities over the next 3-5 years include deploying modular small-scale turbines, advancing integrated hydrologic-ecological-power modeling, conducting pilot demonstrations, developing decision-support tools, and fostering multi-stakeholder collaboration to optimize both energy and ecosystem outcomes. Success measures combine quantitative and qualitative metrics: increased energy recovery, validated modeling frameworks, adoption of tools by operators and regulators, publication of case studies, engagement of partnerships, and policy recognition of E-flows as a strategic energy-water resilience resource. By integrating research, technology, and institutional coordination, this white paper outlines a path to transform underutilized environmental flows into a sustainable energy asset that strengthens grid flexibility, supports environmental stewardship, and enhances national energy-water resilience.