Geomorphology, Sediment, and Habitat
Geomorphology, Sediment, and Habitat
Rivers shape the landscape as they deliver water and sediment from the mountains down to the floodplains and deltas. However, it is possible for the erosion and deposition of sediment by rivers to increase the risk of flooding and impact the health of river ecosystems. USGS geomorphology can provide decision makers with a better understanding of these hazards by evaluating historical trends, current conditions, and potential future impacts from changes in climate and land uses. Hydrologists and geomorphologists of the USGS Washington Water Science Center monitor and study river hydraulics; sediment sources and transport in rivers from the mountains to the ocean; the role of large wood, levees and other features in influencing river channel shape stability; and the relation between all these factors and river habitat and ecology as well as river flooding.
Filter Total Items: 36
Hoh geomorphology
The Issue: Glaciers in the Hoh River watershed are expected to largely disappear by 2050, while flooding is expected to become more intense. Understanding if or how this will impact sediment transport and channel change in the watershed is relevant for salmon habitat, restoration efforts, and flood hazard management. However, there is relatively little information about historical channel...
Nooksack geomorphology
The Issue: Changes in channel geometry in the Nooksack River can reduce flood conveyance capacity, and so increase local flood hazards. Near Everson, WA, sand and gravel accumulations have increased the likelihood that major floods will spill overbank, sending water north over a low drainage divide where it may cause substantial damage to communities in both Washington and British Columbia. Major...
Bolt Creek Wildfire Sediment Runoff and Water Quality
The Issue: Scientists and water-resource managers recognize the increasing impact of wildfires on water supply in the western U.S. The increasing frequency and severity of wildfires are linked to changes in snowpack, warmer temperatures, and drought. Sedimentation following wildfire can impact aquatic habitat, reservoir storage capacity, water quality, and thus public drinking water supplies...
Stormwater Action Monitoring (SAM)
The issue: Stormwater runoff often carries pollutants that degrade water quality in receiving waters. A regional-scale monitoring program is necessary to objectively measure and track progress in reducing stormwater impacts on environmental health. How USGS will help: Scientists from the U.S. Geological Survey (USGS) are monitoring water quality and watershed health for urban and urbanizing areas...
Baseline assessment of PAH concentrations in fish from the Stillaguamish River, Washington
The Issue: Polycyclic aromatic hydrocarbons (PAHs) are a class of oil-derived compounds widely distributed in fresh and marine waters. They pose a significant toxicity risk to fish. It can be challenging to pinpoint the source of PAHs found in wild fish populations. PAHs are widespread and come from many sources, so it is hard to determine whether fish exposure is event-related or consistent with...
Channel Change and Sediment Transport in the Puyallup River Watershed
The Issue: Sediment loads in the Puyallup River and its major tributaries, the White River and Carbon River, are high and river channels are dynamic. While there is a relatively rich history of sediment transport and channel change studies in the Puyallup River and its tributaries, there has not been an integrated assessment of channel-elevation trends in nearly a decade. This lack of up-to-date...
Chehalis Watershed Suspended Sediment Monitoring
The Issue: The Chehalis River deposits sediment in Grays Harbor, which the U.S. Army Corps of Engineers regularly dredges to maintain shipping access. The sources and overall volumes of sediment transport in the lower river were last assessed in the 1960s. Given substantial changes in land-use and watershed regulations over the subsequent half-century, there is an open question as to if or how...
Post-wildfire sedimentation and release of metals to Conconully Reservoir, Washington
Wildfires can negatively impact reservoirs and water supply. In 2021, a wildfire in Okanagan County, Washington, engulfed a large area around Conconully Reservoir. USGS scientists are assessing sediment and water quality in the reservoir and surrounding streams.
Channel change monitoring following the Pilchuck Dam removal
The issue: In the summer of 2020, the Pilchuck Dam will be removed, allowing salmon access to the upper third of the Pilchuck River watershed for the first time in over a century. This removal will be associated with a short period increased sediment delivery, as the river re-works material trapped behind the dam. While the volume of impounded sediment is small and major changes in the downstream...
Assessment of Sediment Quality and Volume behind Enloe Dam
The Issue: The Enloe Dam, a 100-yr old structure on the Similkameen River in Washington State, has not produced hydropower since 1958 and options are being considered for potential removal of the dam. The concentrations of sediment contaminants (primarily trace elements from a long history of mining and smelting operations in the US and Canada) trapped by Enloe Dam are unknown and may be high...
Quantifying suspended-sediment load and transport characteristics in the Calawah and Upper Bogachiel Rivers, Washington
The issue: Salmonid fisheries are an important cultural and economic activity and efforts to support a thriving fisheries industry remain a major priority for the Quileute Tribe on the Olympic Peninsula, Washington. Land use changes can have a profound influence on basin sediment production with direct effects on fisheries (Madej and Ozaki, 2009). Studies are needed to improve estimates of the...
Coarse sediment delivery and routing in the White River
The Issue: Ongoing channel aggradation has reduced flow conveyance along the lower White River, increasing the flood risk in urban-suburban areas. A refined understanding of the delivery, transport and deposition of sediment in the White River, and how those processes may be influenced by climate and existing dam operations, is necessary in order to plan for future flood hazard in the lower White...