HR: 15:00h
AN: H42I-06    [PDF]
TI: A Geomorphic Framework for Identifying Controls on Seasonal Discharge and Stream Temperature Regimes at Multiple Scales Within the Willamette Basin.
AU: * Tague, C
EM: ctague@mail.sdsu.edu
AF: San Diego State University, 5500 Campanile Drive, San Diego, CA 92182-4493 United States
AU: Grant, G E
EM: gordon.grant@orst.edu
AF: USDA Forest Service, Pacific Northwest Research Station, 3200 SW Jefferson Way, Corvallis, OR 97331 United States
AU: Farrell, M J
EM: ctague@mail.sdsu.edu
AF: San Diego State University, 5500 Campanile Drive, San Diego, CA 92182-4493 United States
AU: Lewis, S L
EM: gordon.grant@orst.edu
AF: USDA Forest Service, Pacific Northwest Research Station, 3200 SW Jefferson Way, Corvallis, OR 97331 United States
AB: The seasonal hydrologic regime of the Willamette River basin in Western Oregon is characterized by winter peaks and summer low flows. Low summer streamflows, in particular, place both aquatic ecosystems and human water demands at risk to changes imposed by either land use or climatic fluctuations. Our studies of the correspondence between geological setting and flow regimes demonstrate that this risk is not uniformly distributed across the landscape. Most of the available water in this region is sourced in the Cascade Mountain range, which includes two distinct volcanic provinces, the High and Western Cascades, which differ in terms of the age and degree of dissection of the landscape. Using empirical analysis of streamflow and temperature variation, we demonstrate how this geologic/geomorphic framework can provide a basis for characterizing and predicting summer baseflow, recession behavior, and timing of response to winter recharge, as well as stream temperature at multiple scales for tributaries of the Willamette River. This analysis illustrates how geologic distinctions between the High and Western Cascades have critical implications for interpreting hydrologic flowpaths mechanisms and modeling the sensitivity of this region to environmental change.
DE: 1824 Geomorphology (1625)
DE: 1829 Groundwater hydrology
DE: 1860 Runoff and streamflow
DE: 1871 Surface water quality
DE: 1884 Water supply
SC: Hydrology [H]
MN: 2003 Fall Meeting