This report describes groundwater conditions in the Scott Valley, located in Siskiyou County, California, and the development of a groundwater model representing the alluvial aquifer that can be used to investigate roundwater/surface-water interactions. The goal of this work is to improve understanding of the relationship between land and water use on flow conditions in the Scott River. The groundwater model is applied to examine groundwater conditions given recent levels of groundwater use, and under an alternative water use condition representing partial build-out of the existing groundwater capacity. The partial build-out case, in comparison to the recent condition case, provides a mechanism for examining the impacts of groundwater pumping on the aquifer and on the Scott River. Many other scenarios can be evaluated through specification of alternative conditions to the model input packages. For example, scenarios may be structured to examine how the location and timing of groundwater diversion and use, or how managed recharge, might enhance late season flows
of the Scott River.