Evaluation of Human and Ecological Water Management Tradeoffs in a Seasonal Watershed with Spatially-Distributed Demands

River managers must balance the needs of the ecosystems that rely on the river by leaving water instream, often while also considering human demands. It is especially difficult to balance these water needs in systems that are highly seasonal and have no instream storage (e.g., reservoirs) since water cannot be stored for use throughout the year. An example of a watershed that has both of these characteristics is the South Fork Eel River in coastal northern California. In order to evaluate tradeoffs between human and ecological demands in this system, a water allocation model with water management scenarios and environmental flow requirement scenarios was developed in collaboration with stakeholders and decision-makers to balance the needs of the ecosystem and humans. The water allocation model is capable of considering permitted water diversions, as well as unpermitted diversions, particularly pertaining to cannabis cultivation, which contribute to a significant proportion of water used in forested California watersheds. In total, 11 different human water demand scenarios and 14 different environmental flow requirement ecological demand scenarios were evaluated to identify sensitivity of different parameters and facilitate management efforts. To aid in decision making processes, an interactive GUI is also being collaboratively developed to provide visualizations and performance metrics of model results. Then, the results of the water allocation model were assessed compared to different location-specific characteristics