ABSTRACT:

The Green River is the Colorado River’s largest tributary, contributing a substantial volume of water to the Colorado River Basin that may be retained in reservoirs and utilized to generate hydroelectric power while maintaining important riparian and ecological habitat. Recently, two environmental fish flows for Flaming Gorge Dam along the Upper Green River have been proposed. The primary objective of this study was to assess the effect of these proposed environmental fish flows, in addition to a “run-of-the-river" alternative, on reservoir storage and hydropower generation at Fontenelle, Flaming Gorge, and Lake Powell Reseroirs. Results obtained from Colorado River Simulation Software (CRSS) multi-run simulation models reveal that, for the years 2020-2060, implementation of both proposed environmental fish flows at Flaming Gorge Dam will decrease average monthly storage by 1.6% and increase annual hydropower generation by 0.1%. The environmental fish flow promoting elevated summer baseflows to advantage native Colorado pikeminnow had greater influence on these findings than did the environmental fish flow aimed to disadvantage non-native smallmouth bass. Over the same time period, the “run-of-the-river” alternative will decrease average monthly storage 2.2% and decrease annual hydropower generation 2.7%. These results provide Colorado River Basin water managers, scientists, and stakeholders with additional context regarding the potential future implementation these alternatives.

See readme.txt for explanation of resource contents.

ABSTRACT:

Riparian habitat is a critical component of American southwest ecology. To successfully maintain the ecological integrity of riparian corridors in National Park Service (NPS) units, managers require science-based information quantifying the status and trends of natural resources within riparian areas. This information provides a basis for managers to develop conservation strategies with external partners whose actions impact the ecological integrity of riparian natural resources. As upstream dam operations and water diversions alter the timing and quantity of downstream river flows, park managers specifically require an enhanced understanding of the effect of hydrologic flow on geomorphologic change and vegetation community structure within riparian ecosystems. To contribute to this effort, an exploratory analysis was conducted to integrate hourly water surface elevations (WSE) with digital elevation models (DEMs) at two long-term riparian monitoring locations of the Northern Colorado Plateau Network (NCPN) Inventory and Monitoring (I&M) Division along the Green River within Canyonlands National Park and Dinosaur National Monument. These scripts were developed to visualize inundation period across monitoring sites and within repeat vegetation monitoring plots.

ABSTRACT:

This resource contains python code in a Jupyter Notebook to plot a time series of daily mean, maximum, and minimum discharge values from a USGS stream gauge located along the East Fork of the Virgin River in Zion National Park, Utah.