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This portion of the USGS data release presents bathymetry data collected during surveys performed on the Elwha River delta, Washington in July 2015 (USGS Field Activity Number 2015-648-FA). Bathymetry data were collected using two personal watercraft (PWCs), each equipped with single-beam sonar systems and global navigation satellite system (GNSS) receivers. The PWC sonar systems consisted of an Odom Echotrac CV-100 single-beam echosounder and 200 kHz transducer with a 9° beam angle. Raw acoustic backscatter returns were digitized by the echosounder with a vertical resolution of 1.25 cm. Depths from the echosounders were computed using sound velocity profiles measured using a YSI CastAway CTD during the survey....
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This portion of the USGS data release presents topography data collected during surveys performed on the Elwha River delta, Washington, in May 2011 (USGS Field Activity Number W-04-11-PS). Topography data were collected on foot with global navigation satellite system (GNSS) equipment mounted on backpacks operating in Real-Time Kinematic (RTK) mode. A total of 3 GNSS backpacks, each equipped with a dual-frequency GNSS receiver and handheld data collector, were used during the survey. Differential corrections were transmitted at 1-Hz intervals by a VHF radio to the backpack GNSS receivers from a GNSS base station placed on a benchmark with known horizontal and vertical coordinates relative to the North American Datum...
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This portion of the USGS data release presents bathymetry data collected during surveys performed on the Elwha River delta, Washington in September 2010 (USGS Field Activity Number W-03-10-PS). Bathymetry data were collected using a small boat and a personal watercraft (PWC), each equipped with single-beam sonar systems and global navigation satellite system (GNSS) receivers. The sonar systems on the survey vessels consisted of an Odom Echotrac CV-100 single-beam echosounder and 200 kHz transducer with a 9° beam angle. Raw acoustic backscatter returns were digitized by the echosounder with a vertical resolution of 1.25 cm. Depths from the echosounders were computed using sound velocity profiles measured using a...
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This portion of the USGS data release presents bathymetry data collected during surveys performed in northern Monterey Bay, California in March 2015 (USGS Field Activity Number 2015-625-FA). Bathymetry data were collected using two personal watercraft (PWCs) equipped with single-beam sonar systems and global navigation satellite system (GNSS) receivers. The sonar systems consisted of an Odom Echotrac CV-100 single-beam echosounder and 200 kHz transducer with a 9° beam angle. Raw acoustic backscatter returns were digitized by the echosounder with a vertical resolution of 1.25 cm. Depths from the echosounders were computed using sound velocity profiles measured using a YSI CastAway CTD during the survey. Positioning...
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This portion of the USGS data release presents topography data collected during surveys performed along northern Monterey Bay, California, in March 2015 (USGS Field Activity Number 2015-625-FA). Topographic profiles were collected on foot with GNSS receivers mounted on backpacks. Prior to data collection, vertical distances between the GNSS antennas and the ground were measured using a tape measure. Hand-held data collectors were used to log raw data and display navigational information allowing surveyors to navigate survey lines spaced at 50- to 250-m intervals along the beach. Profiles were surveyed from the landward edge of the study area (either the base of a bluff, engineering structure, or just landward of...
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This portion of the USGS data release presents bathymetry data collected during surveys performed in northern Monterey Bay, California in September 2016 (USGS Field Activity Number 2016-674-FA). Bathymetry data were collected using a personal watercraft (PWC) and small boat equipped with single-beam sonar systems and global navigation satellite system (GNSS) receivers. The sonar systems consisted of an Odom Echotrac CV-100 single-beam echosounder and 200 kHz transducer with a 9° beam angle. Raw acoustic backscatter returns were digitized by the echosounder with a vertical resolution of 1.25 cm. Depths from the echosounders were computed using sound velocity profiles measured using a YSI CastAway CTD during the survey....
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This portion of the USGS data release presents digital elevation models (DEMs) derived from bathymetric and topographic surveys conducted along northern Monterey Bay, California, in September 2017 (USGS Field Activity Number 2017-678-FA). Nearshore bathymetry data were collected using two personal watercraft (PWCs) equipped with single-beam echosounders and survey-grade global navigation satellite system (GNSS) receivers. Topography data were collected using an all-terrain vehicle equipped with a GNSS receiver and on foot with GNSS receivers mounted on backpacks. Additional topography data were collected with a terrestrial lidar scanner. Positions of the survey platforms were referenced to a GNSS base station placed...
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This portion of the USGS data release presents bathymetry data collected during surveys performed in northern Monterey Bay, California in March 2016 (USGS Field Activity Number 2016-627-FA). Bathymetry data were collected using two personal watercraft (PWCs) equipped with single-beam sonar systems and global navigation satellite system (GNSS) receivers. The sonar systems consisted of an Odom Echotrac CV-100 single-beam echosounder and 200 kHz transducer with a 9° beam angle. Raw acoustic backscatter returns were digitized by the echosounder with a vertical resolution of 1.25 cm. Depths from the echosounders were computed using sound velocity profiles measured using a YSI CastAway CTD during the survey. Positioning...
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This portion of the USGS data release presents topography data collected during surveys performed along northern Monterey Bay, California, in March 2017 (USGS Field Activity Number 2017-620-FA). Topographic profiles were collected on foot with GNSS receivers mounted on backpacks. Prior to data collection, vertical distances between the GNSS antennas and the ground were measured using a tape measure. Hand-held data collectors were used to log raw data and display navigational information allowing surveyors to navigate survey lines spaced at 50- to 250-m intervals along the beach. Profiles were surveyed from the landward edge of the study area (either the base of a bluff, engineering structure, or just landward of...
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Two dams on the Elwha River, Washington State, USA trapped over 20 million m3 of mud, sand, and gravel since 1927, reducing downstream sediment fluxes and contributing to erosion of the river's coastal delta. The removal of the Elwha and Glines Canyon dams, initiated in September 2011, induced massive increases in river sediment supply and provided an unprecedented opportunity to examine the geomorphic response of a coastal delta to these increases. Detailed measurements of beach topography and nearshore bathymetry show that ~ 2.5 million m3 of sediment was deposited during the first two years of dam removal, which is ~ 100 times greater than deposition rates measured prior to dam removal. The majority of the deposit...
Categories: Publication; Types: Citation; Tags: Geomorphology
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Capitol Lake was created in 1951 with the construction of a concrete dam and control gate that prevented salt-water intrusion into the newly formed lake and regulated flow of the Deschutes River into southern Puget Sound. Physical processes associated with the former tidally dominated estuary were altered, and the dam structure itself likely caused an increase in retention of sediment flowing into the lake from the Deschutes River. Several efforts to manage sediment accumulation in the lake, including dredging and the construction of sediment traps upriver, failed to stop the lake from filling with sediment. The Deschutes Estuary Feasibility Study (DEFS) was carried out to evaluate the possibility of removing the...
Categories: Publication; Types: Citation; Tags: Open-File Report
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This portion of the data release provides the data used to develop the calibration equation for the images in Digital seafloor images and sediment grain size from the mouth of the Columbia River, Oregon and Washington, 2014 for the estimate of median grain size. This dataset includes 63 still images extracted from digital video imagery of sediment grab samples along with laboratory grain size analysis of the sediment grab samples taken from the mouth of the Columbia River, OR and WA, USA. Still images were extracted from video footage whenever the camera was resting on the sediment sample and individual sediment grains were visible and in focus. The images were used to calculate the calibration curve through auto-correlation...
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Time-series and spatial measurements of nearshore hydrodynamic processes and water properties were made in the Swinomish Channel to quantify the net direction and rates of surface water transport that influence habitat for juvenile Chinook salmon along their primary migratory corridor between the Skagit River and Padilla Bay in northern Puget Sound, Washington. During the spring outmigration of Skagit River Chinook between March and June 2007, currents measured with fixed acoustic doppler current profilers (ADCP) at the south and north end of the Swinomish Channel and with roving ADCP revealed that the currents are highly asymmetric with a dominant flow to the north (toward Padilla Bay). Maximum surface current...
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This portion of the USGS data release presents digital elevation models (DEMs) derived from bathymetric and topographic surveys conducted along northern Monterey Bay, California, in March 2017 (USGS Field Activity Number 2017-620-FA). Nearshore bathymetry data were collected using two personal watercraft (PWCs) equipped with single-beam echosounders and survey-grade global navigation satellite system (GNSS) receivers. Topography data were collected using an all-terrain vehicle equipped with a GNSS receiver and on foot with GNSS receivers mounted on backpacks. Additional topography data were collected with a terrestrial lidar scanner. Positions of the survey platforms were referenced to a GNSS base station placed...
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This portion of the USGS data release presents bathymetry data collected during surveys performed in northern Monterey Bay, California in March 2017 (USGS Field Activity Number 2017-620-FA). Bathymetry data were collected using two personal watercraft (PWCs) equipped with single-beam sonar systems and global navigation satellite system (GNSS) receivers. Depths from the echosounders were computed using sound velocity profiles measured using a YSI CastAway CTD during the survey. Positioning of the survey vessels was was determined at 10-Hz using Trimble R7 GNSS receivers and Zephyr 2 antennas. Output from the GNSS receivers and sonar systems were combined in real time on the PWC by a computer running HYPACK hydrographic...
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This portion of the USGS data release presents sediment grain-size data from on the Elwha River delta, Washington in July and August, 2015 (USGS Field Activities 2015-648-FA and 2015-652-FA). Bed sediment was sampled using a small ponar, or 'grab', sampler on July 28, 2016 from the R/V Frontier at a total of 70 locations in water depths between approximately 1 and 17 m around the delta. An additional 17 samples were obtained by SCUBA divers between July 22 and August 23, 2015 using a 15 cm diameter push corer inserted into the seabed as far as possible to a maximum depth of 15 cm. Forty-eight samples were collected at low tide at intertidal locations on the delta. The locations of grab samples and intertidal samples...
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This portion of the USGS data release presents digital elevation models (DEMs) derived from bathymetric and topographic surveys conducted on the Elwha River delta in July 2018 (USGS Field Activity Number 2018-648-FA). Nearshore bathymetry data were collected using two personal watercraft (PWCs) and a kayak equipped with single-beam echosounders and survey-grade global navigation satellite systems (GNSS) receivers. Topographic data were collected on foot with survey-grade GNSS receivers mounted on backpacks. Positions of the survey platforms were referenced to a GNSS base station placed on a benchmark with known horizontal and vertical coordinates relative to the North American Datum of 1983 (CORS96 realization)...
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The U.S. Geological Survey conducted a bathymetric survey in Little Holland Tract, a flooded agricultural tract, in the northern Sacramento-San Joaquin Delta (the “Delta”) during the summer of 2015. The new bathymetric data were combined with existing data to generate a digital elevation model (DEM) at 1-meter resolution. Little Holland Tract (LHT) was historically diked off for agricultural uses and has been tidally inundated since an accidental levee breach in 1983. Shallow tidal regions such as LHT have the potential to improve habitat quality in the Delta. The DEM of LHT was developed to support ongoing studies of habitat quality in the area and to provide a baseline for evaluating future geomorphic change....
Categories: Publication; Types: Citation; Tags: Open-File Report
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A high-frequency echosounder was used to detect and characterize percent cover and stand height of the benthic filamentous green alga Cladophora sp. on rocky substratum of the Laurentian Great Lakes. Comparisons between in situ observations and estimates of the algal stand characteristics (percent cover, stand height) derived from the acoustic data show good agreement for algal stands that exceeded the height threshold for detection by acoustics (~7.5 cm). Backscatter intensity and volume scattering strength were unable to provide any predictive power for estimating algal biomass. A comparative analysis between the only current commercial software (EcoSAV™) and an alternate method using a graphical user interface...
Categories: Publication; Types: Citation; Tags: Limnology and Oceanography
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Habitat diversity and heterogeneity play a fundamental role in structuring ecological communities. Dam emplacement and removal can fundamentally alter habitat characteristics, which in turn can affect associated biological communities. Beginning in the early 1900s, the Elwha and Glines Canyon dams in Washington, USA, withheld an estimated 30 million tonnes of sediment from river, coastal, and nearshore habitats. During the staged removal of these dams—the largest dam removal project in history—over 14 million tonnes of sediment were released from the former reservoirs. Our interdisciplinary study in coastal habitats—the first of its kind—shows how the physical changes to the river delta and estuary habitats during...
Categories: Publication; Types: Citation; Tags: Ecological Monographs


map background search result map search result map Nearshore circulation and water-column properties in the Skagit River Delta, northern Puget Sound, Washington: juvenile Chinook Salmon habitat availability in the Swinomish Channel Detection and characterization of benthic filamentous algal stands (<i>Cladophora</i> sp.) on rocky substrata using a high-frequency echosounder Nearshore bathymetry data from the Elwha River delta, Washington, July 2015 Surface-sediment grain-size distributions from the Elwha River delta, Washington, July 2015 Topography data from the Elwha River delta, Washington, May 2011 Nearshore bathymetry data from the Elwha River delta, Washington, September 2010 Sediment grain size and digital image calibration parameters from the mouth of the Columbia River, Oregon and Washington, 2014 Nearshore bathymetry data from northern Monterey Bay, California, March 2015 Topography data from northern Monterey Bay, California, March 2015 Nearshore bathymetry data from northern Monterey Bay, California, March 2016 Nearshore bathymetry data from northern Monterey Bay, California, September 2016 Nearshore bathymetry data from northern Monterey Bay, California, March 2017 Topography data from northern Monterey Bay, California, March 2017 Digital elevation models (DEMs) of northern Monterey Bay, California, March 2017 Digital elevation models (DEMs) of northern Monterey Bay, California, September 2017 Digital elevation models (DEMs) of the Elwha River delta, Washington, July 2018 Topography data from the Elwha River delta, Washington, May 2011 Nearshore bathymetry data from the Elwha River delta, Washington, September 2010 Digital elevation models (DEMs) of the Elwha River delta, Washington, July 2018 Nearshore bathymetry data from northern Monterey Bay, California, September 2016 Nearshore bathymetry data from northern Monterey Bay, California, March 2017 Topography data from northern Monterey Bay, California, March 2017 Digital elevation models (DEMs) of northern Monterey Bay, California, March 2017 Digital elevation models (DEMs) of northern Monterey Bay, California, September 2017 Topography data from northern Monterey Bay, California, March 2015 Nearshore bathymetry data from northern Monterey Bay, California, March 2015 Nearshore bathymetry data from northern Monterey Bay, California, March 2016 Detection and characterization of benthic filamentous algal stands (<i>Cladophora</i> sp.) on rocky substrata using a high-frequency echosounder