Columbia River Basalt Group (CRBG) aquifers are commonly thought to be relatively flat lying, laterally extensive, and mostly confined, and therefore not likely to be directly connected to surface water. However, many of the CRBG units in south-central Washington and north-central Oregon were deposited within evolving synclinal structures of the...
Spatial patterns of summer streamflow in the Cascade Mountains of Oregon vary dramatically between the geologically distinct High and Western Cascade regions. A key control is the partitioning of water input between a fast-draining shallow subsurface flow network (Western Cascades) versus a slow-draining deeper groundwater system (High Cascades). These differences...
The specter of climate change looms large over Oregon. Although hydroclimatologic models predict a warmer Oregon, the total volume of precipitation may not change significantly. However, the character (rain vs. snow) and spatial and temporal distributions of precipitation will likely change. The state is already witnessing earlier snowmelt in the...
Many freshwater ecosystems are sustained by a continuous supply of clean groundwater. For example, groundwater may provide late season baseflow to rivers or a sustained high water table in wetlands. These ecosystems, termed GDEs, often are affected by management activities that reduce, interrupt, or contaminate their groundwater supply, including groundwater...
Climate change will continue to profoundly affect water supply and aquatic ecosystems in the Pacific Northwest. Changes such as warmer air temperatures, increases in the proportion of winter rain versus snow, reduced spring snowpack, and earlier snowmelt all affect streamflow. The response to these climate impacts includes earlier runoff peaks,...
The study area lies north-northeast of Crater Lake National Park and is covered by 2 to 3 m of pumice deposited during the climactic eruption of Mount Mazama approximately 7700 years before present. The pumice deposit hosts unconfined, seasonally connected, perched aquifers that support groundwater dependent ecosystems at points of...
The City of Florence, local stakeholders, and partner agencies recently formed the Siuslaw Estuary Partnership (SEP) to address threats to drinking water quality and fish and wildlife habitat in the lower Siuslaw watershed. The Sole Source Dunal Aquifer within the lower Siuslaw watershed, which supplies the City ’s drinking water,...
Effects of climate change in the Cascade Range will likely include more rain, less snow, and earlier snowmelt in the Cascade Range as compared to present conditions. These changes, in turn, will affect the timing of runoff, groundwater recharge, and groundwater discharge to spring-fed streams. This hydrologic response needs to...
Published January 2004. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog
Published March 1991. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog