Water Quality

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...

Blue-green algal blooms in the Willow Creek Reservoir may produce toxins that can be harmful to those that come in contact with them.

Warming air temperature may change water temperature and water column mixing in Oregon’s Crater Lake over the next several decades, potentially impacting the clarity and health of the iconic lake.

The streamflow and water-quality conditions monitored by the USGS in the North Santiam River basin provide valuable information to water resource managers

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.

The Wild and Scenic North Umpqua River is one of the highest-quality waters in the State of Oregon, supporting runs of wild salmon, steelhead, and trout. The USGS has been studying water-quality in the Umpqua River Basin since 1998.

Each autumn Fall Creek Lake is drawn down to allow endangered juvenile salmonids to pass freely through the dam. The drawdowns involve lowering the lake water level to the lake bed, creating a fluvial environment characterized by large amounts of sediment being transported through the dam and into Fall Creek and the Middle Fork Willamette River.

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...

Starting in 1997, the USGS began routinely studying water resources in the Clackamas River Basin. Whether it be assessing harmful algal blooms, runoff issues, streamflow, or watershed health, the USGS has worked with its partners to maintain one of Oregon's most beloved rivers.

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.