Banning, Ryan Oliver B., authorDurnford, Deanna S., advisorFausch, Kurt D., committee memberOad, Ramchand Naraindas, committee member2007-01-032007-01-032010http://hdl.handle.net/10217/39117Department Head: Luis A. Garcia.The decline of stream baseflows along Colorado's high plains streams is degrading aquatic and riparian habitat. Historic strongholds for many plains fish species no longer exist. In Eastern Colorado, center-pivot irrigation is common and clearly contributing to the decline of baseflow in some stream basins. The purpose of this study is to develop a defensible conceptualization of the stream-aquifer system in the Arikaree River basin of eastern Colorado, in part using the results of a preliminary groundwater model developed to predict groundwater levels, analyze stream depletion and examine the effects of irrigation well retirements on groundwater and stream levels. The groundwater conceptualization and model represent the Arikaree River groundwater system of Southern Yuma County where there is significant hydrogeological connection between the Ogallala and alluvial aquifers. Analytical and numerical models presented in this thesis calculate seasonal stream-depletion of the Arikaree River due to nearby wells and similar potential effects of riparian vegetation. Finally, the author examines the river basin water budget in Southern Yuma County to determine possible pumping effects on the amount of available water for streamflow and habitat.masters thesesengCopyright and other restrictions may apply. User is responsible for compliance with all applicable laws. For information about copyright law, please see https://libguides.colostate.edu/copyright.Text