Urban rivers with a history of industrial use can exhibit spatial and temporal variations in contaminant concentrations that may significantly affect risk evaluations and assessment of remediation efforts. To more effectively estimate human and ecological health risks, we evaluated the spatial and temporal distribution of polycyclic aromatic hydrocarbons (PAHs) in...
The goal of this phase of the study was to develop a model of the Tualatin River incorporating Scoggins Creek and Hagg Lake. This tool will be used in conjunction with a hydrologic model, the EPA HSPF model (Johnson, Imhoff, and Kittle, 1984), to analyze management strategies to improve water...
This dissertation examines learning driven adaptations in salmon recovery efforts and water resources management in Oregon. The case study utilizes a framework highlighting the connections between human and natural systems. Semi-structured interviews are used to analyze interactions between rural riparian landowners and watershed council staffs living and working in Oregon’s...
Survey In 1995, the Washington County Soil & Water Conservation District interviewed 90 farmers in northwest Oregon's Tualatin River Basin, using a survey developed by the USDA - Natural Resources Conservation Service (NRCS) and Oregon State University (OSU) Extension Service. Crop rotations, yields, tillage, fertilizer and irrigation practices were recorded....
A relatively stable, persistent and historical problem with elevated NO₃⁻ concentrations in rural drinking wells in the southern Willamette Valley, Oregon is evident. What is the origin of NO₃⁻ in rural drinking water wells in this area? The answer to the question is not simple. Many non-point sources contribute to...
The purposes of this report are to describe the quality of shallow ground water in alluvial aquifers of the Willamette Basin and to identify relationships between shallow ground-water quality and various natural and anthropogenic factors. Several natural and anthropogenic factors (soil characteristics, cumulative thickness of clay above open interval of...
Introduction The Willamette River Flow Project The Nature Conservancy (TNC) and the U. S. Army Corps of Engineers (USACE) are collaborating on a project to determine environmental flow requirements for the Willamette River and its tributaries and to design and test alternative flow releases from the dams that can meet...
A rapid expansion of population and industrialization in recent
years has created new and difficult problems in water resources
management. Prudent management of water quality will require that
more efficient methods be developed for evaluating large volumes of
data on complex river systems, and tabulating the results in a form...
It is no longer possible in any area of the United States to formulate
water resources plans for single purpose projects as has been
done in past years. No longer can one of our greatest natural resources,
water, be used solely for navigation, power generation,
irrigation, or controlled for reducing...
The purpose of this study was to; (1) determine the extent of well water contamination with nitrate and pesticides, and to understand the relationships among nitrate, pesticide, dissolved chloride, dissolved sulfate, well age, and well depth in the southern Willamette Valley, Oregon; and, (2) to investigate local residents' perceptions and...