Assessing the Effects of Water Rights Purchases on Dissolved Oxygen, Stream Temperatures, and Fish Habitat
Location
USU Eccles Conference Center
Event Website
http://water.usu.edu
Start Date
4-5-2016 4:51 PM
End Date
4-5-2016 4:54 PM
Description
Human impacts from land and water development have degraded water quality and altered the physical, chemical, and biological integrity of Nevada’s Walker River. Reduced instream flows and increased nutrient concentrations affect native fish populations through warm daily stream temperatures and low nightly dissolved oxygen concentrations. Environmental water rights purchases are being considered to maintain instream flows, improve water quality, and enhance habitat for native fish species, such as Lahontan cutthroat trout. This study uses the River Modeling System (RMSv4), an hourly, physically-based hydrodynamic and water quality model, to estimate streamflows, temperatures, and dissolved oxygen concentrations in the Walker River. We simulate stream temperature and dissolved oxygen changes from potential environmental water rights purchases to prioritize the time periods and locations that water purchases most enhance stream temperatures and dissolved oxygen concentrations for aquatic habitat. Modeling results indicate that increased water rights purchases generally affect dissolved oxygen in two ways. First, more streamflow increases the thermal mass of the river, cooling daily stream temperatures and warming nightly temperatures. This prevents conditions that cause the lowest nightly dissolved oxygen concentrations (acute thresholds are
Assessing the Effects of Water Rights Purchases on Dissolved Oxygen, Stream Temperatures, and Fish Habitat
USU Eccles Conference Center
Human impacts from land and water development have degraded water quality and altered the physical, chemical, and biological integrity of Nevada’s Walker River. Reduced instream flows and increased nutrient concentrations affect native fish populations through warm daily stream temperatures and low nightly dissolved oxygen concentrations. Environmental water rights purchases are being considered to maintain instream flows, improve water quality, and enhance habitat for native fish species, such as Lahontan cutthroat trout. This study uses the River Modeling System (RMSv4), an hourly, physically-based hydrodynamic and water quality model, to estimate streamflows, temperatures, and dissolved oxygen concentrations in the Walker River. We simulate stream temperature and dissolved oxygen changes from potential environmental water rights purchases to prioritize the time periods and locations that water purchases most enhance stream temperatures and dissolved oxygen concentrations for aquatic habitat. Modeling results indicate that increased water rights purchases generally affect dissolved oxygen in two ways. First, more streamflow increases the thermal mass of the river, cooling daily stream temperatures and warming nightly temperatures. This prevents conditions that cause the lowest nightly dissolved oxygen concentrations (acute thresholds are
https://digitalcommons.usu.edu/runoff/2016/2016Posters/8
Comments
A poster by Nathaniel Mouzon, who is with Utah State University, Ecology Center and the Department of Watershed Sciences