Oceanographer with the USGS Pacific Coastal and Marine Science Center
Explore my published data sets on USGS ScienceBase, or choose the Data and Tools tab below.
Education and Certifications
College of Oceanic and Atmospheric Sciences, Oregon State University, Corvallis, OR
M.S., Oceanography, November 2004Humboldt State University, Arcata, CA
B.S., Oceanography, May 2002 (with honors)
Science and Products
Fluvial delivery and wave resuspension of sediment in a sheltered, urbanized Pacific Northwest estuary
Nearshore subtidal community response during and after sediment disturbance associated with dam removal
Monitoring and modeling dispersal of a submerged nearshore berm at the mouth of the Columbia River, USA
Assessment of vulnerabilities and opportunities to restore marsh sediment supply at Nisqually River Delta, west-central Washington
Ancient winds, waves, and atmosphere in Gale Crater, Mars, inferred from sedimentary structures and wave modeling
Cohesive sediment modeling in a shallow estuary: Model and environmental implications of sediment parameter variation
Numerical models of sediment transport in estuarine systems rely on parameter values that are often poorly constrained and can vary on timescales relevant to model processes. The selection of parameter values can affect the accuracy of model predictions, while environmental variation of these parameters can impact the temporal and spatial ranges of sediment fluxes, erosion, and deposition in the r
Sediment export and impacts associated with river delta channelization compound estuary vulnerability to sea-level rise, Skagit River Delta, Washington, USA
Observations of coastal change and numerical modeling of sediment-transport pathways at the mouth of the Columbia River and its adjacent littoral cell
World’s largest dam removal reverses coastal erosion
A regime shift in sediment export from a coastal watershed during a record wet winter, California: Implications for landscape response to hydroclimatic extremes
Morphodynamic evolution following sediment release from the world’s largest dam removal
Sediment pulses can cause widespread, complex changes to rivers and coastal regions. Quantifying landscape response to sediment-supply changes is a long-standing problem in geomorphology, but the unanticipated nature of most sediment pulses rarely allows for detailed measurement of associated landscape processes and evolution. The intentional removal of two large dams on the Elwha River (Washingto
Increased sediment load during a large-scale dam removal changes nearshore subtidal communities
Non-USGS Publications**
**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.
Estuaries and large river deltas in the Pacific Northwest
Exploring the USGS Science Data Life Cycle in the Cloud
Digital seafloor images, sediment grain size, bathymetry, and water velocity data from the lower Columbia River, Oregon and Washington, 2021
Aerial imagery and structure-from-motion data products from UAS surveys of the beaches at Fort Stevens State Park, OR, and Cape Disappointment State Park, WA
Bathymetry, topography, and sediment grain-size data from the Elwha River delta, Washington, August 2022
Hydrodynamic and sediment transport data from Whale's Tail marsh and adjacent waters in South San Francisco Bay, California 2021-2022
Bathymetry and acoustic backscatter data from Floras Lake, Oregon, June 2018
Oceanographic and water-quality measurements collected in Bellingham Bay, Washington, USA, 2019 to 2021
Bathymetry data and sediment transport modeling of a submerged nearshore berm at the mouth of the Columbia River, Oregon and Washington, 2020-2021
Modeling surface gravity waves on a schematized ancient lake on Mars
Bathymetry, topography, and sediment grain-size data from the Elwha River delta, Washington, July 2018
Time-series measurements of pressure, conductivity, temperature, and water level collected in Puget Sound and Bellingham Bay, Washington, USA, 2018 to 2021
Beach topography and nearshore bathymetry of the Columbia River littoral cell, Washington and Oregon
Eelgrass distributions and bathymetry of Bellingham Bay, Washington, 2019
Science and Products
- Publications
Filter Total Items: 33
Fluvial delivery and wave resuspension of sediment in a sheltered, urbanized Pacific Northwest estuary
The sequence and timing of sediment delivery and redistribution in coastal systems is important for shoreline stability, ecosystem services, and remediation planning. In temperate estuaries, understanding the role of fluvial sediment delivery and dispersal relative to wind and wave remobilization processes is particularly important to address the fate of contaminants, many of which adsorb to fineAuthorsDaniel J. Nowacki, Andrew W. Stevens, Renee K. Takesue, Eric E. GrossmanNearshore subtidal community response during and after sediment disturbance associated with dam removal
Dam removal is used increasingly to restore aquatic ecosystems and remove unnecessary or high-risk infrastructure. As the number of removals increases, there is a growing understanding about the hydrologic, geomorphic, and ecological responses to these removals. Most dam removal studies, however, focus on river and watershed responses to dam removal. The removal of two dams on the Elwha River provAuthorsStephen P. Rubin, Melissa M. Foley, Ian M. Miller, Andrew W. Stevens, Jonathan Warrick, Helen D. Berry, Nancy E. Elder, Matthew M. Beirne, Guy GelfenbaumMonitoring and modeling dispersal of a submerged nearshore berm at the mouth of the Columbia River, USA
A submerged, low-relief nearshore berm was constructed in the Pacific Ocean near the mouth of the Columbia River, USA, using 216,000 m3 of sediment dredged from the adjacent navigation channel. The material dredged from the navigation channel was placed on the northern flank of the ebb-tidal delta in water depths between 12 and 15 m and created a distinct feature that could be tracked over time. FAuthorsAndrew W. Stevens, Hans R. Moritz, Edwin PL Elias, Guy R. Gelfenbaum, Peter R Ruggiero, Stuart G Pearson, James M McMillan, George M KaminskyAssessment of vulnerabilities and opportunities to restore marsh sediment supply at Nisqually River Delta, west-central Washington
A cascading set of hazards to coastal environments is intimately tied to sediment transport and includes the flooding and erosion of shorelines and habitats that support communities, industry, infrastructure, and ecosystem functions (for example, habitats critical to fisheries). This report summarizes modeling and measurement data used to evaluate the sediment budget of the Nisqually River Delta,AuthorsEric E. Grossman, Sean C. Crosby, Andrew W. Stevens, Daniel J. Nowacki, Nathan R. vanArendonk, Christopher A. CurranAncient winds, waves, and atmosphere in Gale Crater, Mars, inferred from sedimentary structures and wave modeling
Wave modeling and analysis of sedimentary structures were used to evaluate whether four examples of symmetrical, reversing, or straight-crested bedforms in Gale crater sandstones are preserved wave ripples; deposition by waves would demonstrate that the lake was not covered by ice at that time. Wave modeling indicates that regardless of atmospheric density, winds that exceeded the threshold of aeoAuthorsDM Rubin, MAG Lapotre, Andrew W. Stevens, MP Lamb, CM Fedo, JP Grotzinger, S. Gupta, KM Stack, AR Vasavada, SG Banham, AB Bryk, G. Caravaca, JP Christian, Lauren A. Edgar, M. C. MalinCohesive sediment modeling in a shallow estuary: Model and environmental implications of sediment parameter variation
Numerical models of sediment transport in estuarine systems rely on parameter values that are often poorly constrained and can vary on timescales relevant to model processes. The selection of parameter values can affect the accuracy of model predictions, while environmental variation of these parameters can impact the temporal and spatial ranges of sediment fluxes, erosion, and deposition in the r
AuthorsRachel Allen, Jessica R. Lacy, Andrew W. StevensSediment export and impacts associated with river delta channelization compound estuary vulnerability to sea-level rise, Skagit River Delta, Washington, USA
Improved understanding of the budget and retention of sediment in river deltas is becoming increasingly important to mitigate and plan for impacts expected with sea level rise. In this study, analyses of historical bathymetric change, sediment core stratigraphy, and modeling are used to evaluate the sediment budget and environmental response of the largest river delta in the U.S. Pacific NorthwestAuthorsEric E. Grossman, Andrew W. Stevens, Peter Dartnell, Doug A George, David FinlaysonObservations of coastal change and numerical modeling of sediment-transport pathways at the mouth of the Columbia River and its adjacent littoral cell
Bathymetric and topographic surveys performed annually along the coastlines of northern Oregon and southwestern Washington documented changes in beach and nearshore morphology between 2014 and 2019. Volume change analysis revealed measurable localized erosion and deposition throughout the study area, but significant net erosion at the regional scale (several kilometers [km]) was limited to BensonAuthorsAndrew W. Stevens, Edwin Elias, Stuart Pearson, George M. Kaminsky, Peter R Ruggiero, Heather M. Weiner, Guy R. GelfenbaumWorld’s largest dam removal reverses coastal erosion
Coastal erosion outpaces land generation along many of the world’s deltas and a significant percentage of shorelines, and human-caused alterations to coastal sediment budgets can be important drivers of this erosion. For sediment-starved and erosion-prone coasts, large-scale enhancement of sediment supply may be an important, but poorly understood, management option. Here we provide new topographiAuthorsJonathan Warrick, Andrew W. Stevens, Ian M. Miller, Shawn R Harrison, Andrew C. Ritchie, Guy R. GelfenbaumA regime shift in sediment export from a coastal watershed during a record wet winter, California: Implications for landscape response to hydroclimatic extremes
Small, steep watersheds are prolific sediment sources from which sediment flux is highly sensitive to climatic changes. Storm intensity and frequency are widely expected to increase during the 21st century, and so assessing the response of small, steep watersheds to extreme rainfall is essential to understanding landscape response to climate change. During record winter rainfall in 2016–2017, theAuthorsAmy E. East, Andrew W. Stevens, Andrew C. Ritchie, Patrick L. Barnard, Pamela L. Campbell‐Swarzenski, Brian D. Collins, Christopher H. ConawayMorphodynamic evolution following sediment release from the world’s largest dam removal
Sediment pulses can cause widespread, complex changes to rivers and coastal regions. Quantifying landscape response to sediment-supply changes is a long-standing problem in geomorphology, but the unanticipated nature of most sediment pulses rarely allows for detailed measurement of associated landscape processes and evolution. The intentional removal of two large dams on the Elwha River (Washingto
AuthorsAndrew C. Ritchie, Jonathan Warrick, Amy E. East, Christopher S. Magirl, Andrew W. Stevens, Jennifer A. Bountry, Timothy J. Randle, Christopher A. Curran, Robert C. Hilldale, Jeffrey J. Duda, Ian M. Miller, George R. Pess, Emily Eidam, Melissa M. Foley, Randall McCoy, Andrea S. OgstonByEcosystems Mission Area, Natural Hazards Mission Area, Water Resources Mission Area, Coastal and Marine Hazards and Resources Program, Arizona Water Science Center, Pacific Coastal and Marine Science Center, Washington Water Science Center, Western Fisheries Research Center, Sediment Lab Suite and Carbon Analysis LaboratoryIncreased sediment load during a large-scale dam removal changes nearshore subtidal communities
The coastal marine ecosystem near the Elwha River was altered by a massive sediment influx—over 10 million tonnes—during the staged three-year removal of two hydropower dams. We used time series of bathymetry, substrate grain size, remotely sensed turbidity, scuba dive surveys, and towed video observations collected before and during dam removal to assess responses of the nearshore subtidal communAuthorsStephen P. Rubin, Ian M. Miller, Melissa M. Foley, Helen D. Berry, Jeffrey J. Duda, Benjamin Hudson, Nancy E. Elder, Matthew M. Beirne, Jonathan Warrick, Michael L. McHenry, Andrew W. Stevens, Emily Eidam, Andrea Ogston, Guy R. Gelfenbaum, Rob PedersenNon-USGS Publications**
Stevens, A.W. , Wheatcroft, R.A., Wiberg, P.L., 2007, Seabed properties and sediment erodibility along the western Adriatic margin, Italy: Continental Shelf Research, v. 27, i. 3–4, pp. 400-416, doi: 10.1016/j.csr.2005.09.009Wheatcroft, R.A., Stevens, A.W., Hunt, L.M., Milligan, T.G., 2006, The large-scale distribution and internal geometry of the fall 2000 Po River flood deposit: Evidence from digital X-radiography: Continental Shelf Research, v. 26, i. 4, pp. 499-516, doi: 10.1016/j.csr.2006.01.002Borgeld, J.C., and A.W. Stevens, 2005, Humboldt Bay, California, surface sediments 2000-01, in Schlosser, S.C., and R. Rasmussen, eds., Proceedings of the Humboldt Bay symposium; Current perspectives on the physical and biological processes of Humboldt Bay, p. 51-64**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.
- Science
Estuaries and large river deltas in the Pacific Northwest
Essential habitat for wild salmon and other wildlife borders river deltas and estuaries in the Pacific Northwest. These estuaries also support industry, agriculture, and a large human population that’s expected to double by the year 2060, but each could suffer from more severe river floods, higher sea level, and storm surges caused by climate change.Exploring the USGS Science Data Life Cycle in the Cloud
Executive Summary Traditionally in the USGS, data is processed and analyzed on local researcher computers, then moved to centralized, remote computers for preservation and publishing (ScienceBase, Pubs Warehouse). This approach requires each researcher to have the necessary hardware and software for processing and analysis, and also to bring all external data required for the workflow over the int - Data
Filter Total Items: 37
Digital seafloor images, sediment grain size, bathymetry, and water velocity data from the lower Columbia River, Oregon and Washington, 2021
Growth of subaqueous sand dunes commonly causes shoaling in engineered river channels that necessitates costly dredging to maintain adequate depths for navigation. The factors that result in sand wave growth are theoretically understood from laboratory experiments, but the capacity to predict sand wave geometries in field settings is limited due to temporal and spatial variability in hydrodynamicsAerial imagery and structure-from-motion data products from UAS surveys of the beaches at Fort Stevens State Park, OR, and Cape Disappointment State Park, WA
This data release presents aerial imagery and structure-from-motion (SfM) data products from uncrewed aerial system (UAS) surveys conducted on the ocean beaches adjacent to the Columbia River Mouth at the Oregon-Washington border. The surveys cover approximately 3 kilometers of Benson Beach at Cape Disappointment State Park north of the Columbia River mouth, in Washington, and 3 kilometers of theBathymetry, topography, and sediment grain-size data from the Elwha River delta, Washington, August 2022
Two dams on the Elwha River, Washington State, USA trapped over 20 million m3 of sediment, reducing downstream sediment fluxes and contributing to erosion of the river's coastal delta. The removal of the Elwha and Glines Canyon dams between 2011 and 2014 induced massive increases in river sediment supply and provided an unprecedented opportunity to examine the response of a delta system to changesHydrodynamic and sediment transport data from Whale's Tail marsh and adjacent waters in South San Francisco Bay, California 2021-2022
The U.S. Geological Survey Pacific Coastal and Marine Science Center collected hydrodynamic and sediment-transport data at shallow water sites in South San Francisco Bay and in the Whale's Tail South marsh in Eden Landing Ecological Reserve in Alameda County, CA in 2021 and 2022. This data release includes hydrodynamic and sediment transport time-series data spanning from June 2021 to January 2022Bathymetry and acoustic backscatter data from Floras Lake, Oregon, June 2018
This publication releases single-beam bathymetry and backscatter datasets acquired by the U.S. Geological Survey (USGS) during surveys performed on Floras Lake, Oregon, in June 2018. Bathymetry and backscatter data were collected using two personal watercraft (PWCs) equipped with single-beam sonar systems, sidescan sonar systems, and global navigation satellite system (GNSS) receivers. BathymetryOceanographic and water-quality measurements collected in Bellingham Bay, Washington, USA, 2019 to 2021
Bottom-landing and floating platforms with instrumentation to measure currents, waves, water level, optical turbidity, water temperature, and conductivity were deployed at four locations in Bellingham Bay, Washington, USA. Platforms were deployed during three separate periods: July 30, 2019-November 14, 2019; November 19, 2019-February 5, 2020; and January 22, 2021-April 13, 2021. Additionally, waBathymetry data and sediment transport modeling of a submerged nearshore berm at the mouth of the Columbia River, Oregon and Washington, 2020-2021
This data release contains gridded bathymetry data from repeated multibeam sonar surveys and input files for a hydrodynamic and sediment transport model application of the mouth of the Columbia River (MCR), Oregon and Washington. The bathymetry data were collected by the U.S. Army Corps of Engineers Portland District Surveys Section between September 9, 2020, and March 10, 2021, to characterize thModeling surface gravity waves on a schematized ancient lake on Mars
This data release provides a wave model application and wave parameters derived from simulations of a schematized ancient lake on Mars. The phase-averaged wave model, SWAN, was applied within the Delft3D modeling system (Deltares, 2018) with reduced gravity and a range of atmospheric densities and wind speeds to simulate potential conditions that could generate wind waves on Mars. Wave modeling prBathymetry, topography, and sediment grain-size data from the Elwha River delta, Washington, July 2018
Two dams on the Elwha River, Washington State, USA trapped over 20 million m3 of sediment, reducing downstream sediment fluxes and contributing to erosion of the river's coastal delta. The removal of the Elwha and Glines Canyon dams between 2011 and 2014 induced massive increases in river sediment supply and provided an unprecedented opportunity to examine the response of a delta system to changesTime-series measurements of pressure, conductivity, temperature, and water level collected in Puget Sound and Bellingham Bay, Washington, USA, 2018 to 2021
Pressure, conductivity, temperature, and water level relative the North American Vertical Datum of 1988 (NAVD88) were measured at seven locations in Puget Sound and Bellingham Bay, Washington, USA, from November 2, 2018 to June 4, 2021. These data were collected using submersible pressure-conductivity-temperature sensors mounted on piers to support studies of extreme water levels and flooding hazaBeach topography and nearshore bathymetry of the Columbia River littoral cell, Washington and Oregon
This data release presents beach topography and nearshore bathymetry data from repeated surveys performed by a team of scientists from the U.S. Geological Survey, Washington State Department of Ecology, and Oregon State University in the Columbia River littoral cell (CRLC), Washington and Oregon. The CRLC extends approximately 165 kilometers between Point Grenville (PG), Washington, and TillamookEelgrass distributions and bathymetry of Bellingham Bay, Washington, 2019
This data release presents eelgrass distributions and bathymetry data derived from acoustic surveys of Bellingham Bay, Washington. Survey operations were conducted between February 16 and February 21, 2019 (USGS Field Activity Number 2019-606-FA) by a team of scientists from the U.S. Geological Survey Pacific Coastal and Marine Science Center and Washington State Department of Ecology. Eelgrass an - Multimedia
Filter Total Items: 42PCMSC scientist measuring land-surface elevation near the bay-marsh edge of Whale's Tail South marsh
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