The Clean Water Act imposes Total Maximum Daily Load (TMDL) limits on pollutant concentrations within wastewater effluent; in Oregon, thermal discharge is one of the pollutants subject to regulation. The City of Woodburn, Oregon, funded a series of pilot scale studies to investigate the utility of natural systems to reduce...
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...
By the early 1990s, the citizens of Tillamook County recognized that environmental problems facing Tillamook Bay threatened the very future of those residing here. Declining fish runs meant loss of income for commercial fishermen, tackle shops, hotel owners, and other fishing - dependent businesses. Decreasing water quality meant violations of...
About one-third of the land in the Tualatin Basin is used for agricultural production (Miner, Scott, and Wood, 1994). The variety of crops produced includes grains, specialty seeds, vegetables, fruits, berries, and nursery corps. Cattle and hog enterprises are the most prevalent livestock operations in the area (measured by number...
This study explores how environmental governance mechanisms affect state management of forest roads to address the chronic delivery of sediment to streams in Oregon, Washington, and California on private and state forestlands. Forest roads can degrade water quality and harm aquatic life when runoff mobilizes fine sediments from the road...
To better understand the impact of land use on stream nutrient export, a synoptic sampling of 57 sub-basins within the Willamette River basin was conducted during winter baseflow conditions (February 2009). I assessed whether stream dissolved organic carbon (DOC), NO₃⁻ and Cl⁻ and specific ultra-violet absorbance (SUVA) values were correlated...
Surface water quality is a growing concern in the Willamette River Basin and elsewhere. The region's growing population is dependent on the availability of clean water for drinking water, irrigation, wastewater dilution, and wildlife habitat. Watershed management to produce economic goods and environmental services requires an understanding of basic hydrologic...
Wetland restoration mitigates effects of agricultural development on water quality, flooding, and habitat loss. Multi-objective optimization for wetland locations and sizes has not included objective functions for water quality, hydrology, and habitat in unison, limiting analysis of trade-offs among these ecosystem services. This study establishes two methods to improve the...
Thesis summarizes interviews with growers residing within the Groundwater Management Area (GWMA) in the Southern Willamette Valley of Oregon. Informal and semi-structured interviews were used to identify perceived impediments and incentives perceived by local farmers in following best management practices related to water quality. Results from the interviews were coded...