Ecology Team

SELDM facilitates analysis by providing precipitation, pre-storm streamflow, and other variables by region or from hydrologically similar sites.

Welcome to the Willamette River Study page. Here you will find links to USGS research for the Willamette River and the Willamette River Basin.

Hills Creek, Lookout Point, and Dexter Dams are located on the Middle Fork Willamette River upstream of Eugene in western Oregon, and are important resources managed by the U.S. Army Corps of Engineers (USACE) for flood control, hydroelectric power, recreation, navigation, and irrigation. On the South Santiam River east of Albany in western Oregon, Green Peter and Foster Dams provide functions and...

The U.S. Army Corps of Engineers operates 12 dams in the Willamette River Basin. The dams alter natural temperature and hydrologic regimes. Unnatural water temperatures can negatively impact all life stages of salmonid fish species. Water temperature in the mainstem Willamette River regularly exceeds the standard of 18.0 °C (64.4 °F) designated for salmon and trout rearing and migration for mid...

Fish, wildlife, and human populations along the lower Columbia River are exposed to an ever-growing variety of contaminants as a result of increasing urbanization, industrialization, and agricultural development.

USGS total dissolved gas (TDG) data help guide spill and discharge management from dams operated along the lower Columbia River.

Pacific Lampreys (Entosphenus tridentatus) have lived in the Columbia River Basin for millenia and have great ecological and cultural importance. Lamprey populations in the Pacific Northwest and other parts of the world have declined dramatically in recent decades, probably owing to multiple causes. The role of habitat contamination in the declines has rarely been studied and was the main...

The USGS has characterized nutrient concentrations in the Klamath River and Lost River drainages over multiple years, identified spatial and temporal patterns in nutrient and organic carbon concentrations, and quantified surface water nutrient loads entering and exiting the Klamath Project.

U.S. Geological Survey (USGS) scientists report that glyphosate, known commercially by many trade names, and its degradation product AMPA (aminomethylphosphonic acid) are transported off-site from agricultural and urban sources and occur widely in the environment. This study is the largest and most comprehensive assessment of the environmental occurrence of glyphosate and AMPA in the United States...

Cottage Grove Reservoir is an impoundment of the Coast Fork of the Willamette River and is managed by the U.S. Army Corps of Engineers (USACE) as part of the Willamette Valley Flood Control Plan. The reservoir is currently under a fish consumption advisory because of elevated levels of mercury in fish tissue observed in an Oregon Department of Environmental Quality sampling survey in 2003 (Oregon...

Drinking water for the city of Eugene, Oregon, is drawn from the McKenzie River, a high-quality source that is nonetheless threatened by urban, agricultural, and forestry land uses upstream as well as by changes in water management in the watershed. In 2002, the USGS began monitoring dissolved pesticides in the McKenzie River and its tributaries.

Environmental flows are defined as "streamflow needed to sustain ecosystems while continuing to meet human needs."