and information quality guidelines issued by the U.S. Department of Energy. Though this report does not constitute "influential" information, as that term is defined in DOE's information quality guidelines or the Office of Management and Budget's Information Quality Bulletin for Peer Review (Bulletin), the study was reviewed both internally and externally prior to publication.

The authors would like to thank the many stakeholders with whom we have engaged to elicit feedback on the opportunities and challenges associated with developing and deploying standard modular hydropower technologies. Ongoing engagement with these technology innovators, commercial service/equipment providers, project developers, and environmental stewards has yielded insight into the myriad perspectives and experiences that shape the current hydropower landscape and inform standard modular hydropower research.

No abstract

Managing energy, water, and environmental priorities and constraints within a cascade hydropower system is a challenging multiobjective optimization effort that requires advanced modeling and forecasting tools. Within the mid-Columbia River system, there is currently a lack of specific solutions for predicting how coordinated operational decisions can mitigate the impacts of total dissolved gas (TDG) supersaturation while satisfying multiple additional policy and hydropower generation objectives. In this study, a reduced-order TDG uptake equation is developed that predicts tailrace TDG at seven hydropower facilities on the mid-Columbia River. The equation is incorporated into a general multiobjective river, reservoir, and hydropower optimization tool as a prioritized operating goal within a broader set of system-level objectives and constraints. A test case is presented to assess the response of TDG and hydropower generation when TDG supersaturation is optimized to remain under state water-quality standards. Satisfaction of TDG as an operating goal is highly dependent on whether constraints that limit TDG uptake are implemented at a higher priority than generation requests. According to the model, an opportunity exists to reduce TDG supersaturation and meet hydropower generation requirements by shifting spillway flows to different time periods. A coordinated effort between all project owners is required to implement systemwide optimized solutions that satisfy the operating policies of all stakeholders.

The authors would like to thank the many stakeholders with whom we have engaged to elicit feedback on the opportunities and challenges associated with developing and deploying standard modular hydropower technologies. Ongoing engagement with these technology innovators, commercial service/equipment providers, project developers, and environmental stewards has yielded insight into the myriad perspectives and experiences that shape the current hydropower landscape and inform standard modular hydropower research.