A geophysical and geological survey was conducted at the mouth of the Connecticut River from Old Saybrook to Essex, Connecticut, in September 2012. Approximately 230 linear kilometers of digital Chirp subbottom (seismic-reflection) and 234-kilohertz interferometric sonar (bathymetric and backscatter) data were collected along with sediment samples, riverbed photographs, and (or) video at 88 sites within the geophysical survey area. Sediment grab samples were collected at 72 of the 88 sampling sites, video ...

A geophysical and geological survey was conducted at the mouth of the Connecticut River from Old Saybrook to Essex, Connecticut, in September 2012. Approximately 230 linear kilometers of digital Chirp subbottom (seismic-reflection) and 234-kilohertz interferometric sonar (bathymetric and backscatter) data were collected along with sediment samples, riverbed photographs, and (or) video at 88 sites within the geophysical survey area. Sediment grab samples were collected at 72 of the 88 sampling sites, video ...

This part of the data release presents acoustic backscatter data collected on February 1, 2011, in the Sacramento River from the confluence of the Feather River to Knights Landing. The data were collected by the USGS Pacific Coastal and Marine Science Center (PCMSC) team with collaboration and funding from the U.S. Army Corp of Engineers. This project used interferometric sidescan sonar to characterize the riverbed and channel banks along a 12 mile reach of the Sacramento River, California (River Mile 79 ...

A geophysical and geological survey was conducted at the mouth of the Connecticut River from Old Saybrook to Essex, Connecticut, in September 2012. Approximately 230 linear kilometers of digital Chirp subbottom (seismic-reflection) and 234-kilohertz interferometric sonar (bathymetric and backscatter) data were collected along with sediment samples, riverbed photographs, and (or) video at 88 sites within the geophysical survey area. Sediment grab samples were collected at 72 of the 88 sampling sites, video ...

Bathymetric change grids covering the periods of time from 1992 to 1998 and from 1994 to 2004 are presented. The grids cover a portion of the Sacramento River near Rio Vista, California, extending partially upstream on Cache and Steamboat sloughs by the Ryer Island Ferry, as well as continuing up the Sacramento River towards Isleton. Positive grid values indicate accretion, or a shallowing of the surface bathymetric surface, and negative grid values indicate erosion, or a deepening of the bathymetric ...

Bathymetric change grids covering the periods of time from 1934 to 2011, from 2011 to 2018, and from 1934 to 2018 are presented. The grids cover a portion of the Mokelumne River, California, starting at its terminus at the San Joaquin River and moving upriver to the confluences of the north and south branches of the Mokelumne. Positive grid values indicate accretion, or a shallowing of the surface bathymetric surface, and negative grid values indicate erosion, or a deepening of the bathymetric surface. ...

This part of the data release presents a digital elevation model (DEM) created from bathymetry data collected on February 1, 2011, in the Sacramento River from the confluence of the Feather River to Knights Landing. The data were collected by the USGS Pacific Coastal and Marine Science Center (PCMSC) team with collaboration and funding from the U.S. Army Corps of Engineers. This project used interferometric sidescan sonar to characterize the riverbed and channel banks along a 12 mile reach of the Sacramento ...

Daily values of discharge and sediment loads were measured and estimated at U.S. Geological Survey gaging station 12046260, on the Elwha River at the diversion near Port Angeles, Washington. Daily data are reported from September 15, 2011 to September 30, 2016. Specific data include (1) date; (2) discharge; (3) suspended-sediment concentration and one standard-deviation bounds; (4) percentage of fine-grained particles (silts and clays) in suspension; (5) loads of total suspended-sediment, fine-grained ...

Digital elevation models (DEMs) of the lower Elwha River, Washington, were created by synthesizing lidar and PlaneCam Structure-from-Motion (SfM) data. Lidar and still digital photographs were collected by airplane during surveys from 2012 to 2016. The digital photographs were used to create a SfM digital surface model. Each DEM represents the ending conditions for that water year (for example, the 2013 DEM represents conditions at approximately September 30, 2013). The final DEMs, presented here, were ...

This dataset presents elevation measurements of two dams on the Elwha River, Washington, during their removal processes from 2008 to 2013. Elevation measurements of the Elwha Dam were taken from October 2008 to March 2012. Elevation measurements of the Glines Canyon dam, which was further upstream than the Elwha Dam, were taken from October 2010 to October 2013. The measurements were by the U.S. Bureau of Reclamation as part of a study investigating the river channel's morphological responses to dam removal ...

Pebble-count data were collected during summer surveys (2013, 2015, 2016, 2017, 2018, 2019, 2020, and 2021) at ten sites along the Carmel River, California. Grain-size measurements were made at four to six transects per site using a 0.5 by 0.5 m sampling frame, with approximately 100 sediment-particle counts per transect. Each transect was defined by coordinates on the left and right sides of the river, and sediment grain sizes were measured at five equally spaced locations within the bankfull channel on ...

A geophysical and geological survey was conducted at the mouth of the Connecticut River from Old Saybrook to Essex, Connecticut, in September 2012. Approximately 230 linear kilometers of digital Chirp subbottom (seismic-reflection) and 234-kilohertz interferometric sonar (bathymetric and backscatter) data were collected along with sediment samples, riverbed photographs, and (or) video at 88 sites within the geophysical survey area. Sediment grab samples were collected at 72 of the 88 sampling sites, video ...

A geophysical and geological survey was conducted at the mouth of the Connecticut River from Old Saybrook to Essex, Connecticut, in September 2012. Approximately 230 linear kilometers of digital Chirp subbottom (seismic-reflection) and 234-kilohertz interferometric sonar (bathymetric and backscatter) data were collected along with sediment samples, riverbed photographs, and (or) video at 88 sites within the geophysical survey area. Sediment grab samples were collected at 72 of the 88 sampling sites, video ...

A geophysical and geological survey was conducted at the mouth of the Connecticut River from Old Saybrook to Essex, Connecticut, in September 2012. Approximately 230 linear kilometers of digital Chirp subbottom (seismic-reflection) and 234-kilohertz interferometric sonar (bathymetric and backscatter) data were collected along with sediment samples, riverbed photographs, and (or) video at 88 sites within the geophysical survey area. Sediment grab samples were collected at 72 of the 88 sampling sites, video ...

Five-stage sequential extractions were performed on ultramafic soil from Bosque Susua and Guanica Dry Forest, stream sediment from Rios Loco and Yauco, and nearshore sediment from Guanica Bay in southwest Puerto Rico. Sequential extractions showed partitioning of geologically enriched metals and other elements among five phases: 1) adsorbed and calcium-bound, 2) iron-, manganese-oxyhydroxide-bound, 3) crystalline iron-oxide-bound, 4) sulfide-bound, and 5) residual. Total element contents are also reported. ...

Bedload sediment transport was calculated on the Elwha River, Washington to measure the amount of sediment transported along the riverbed during the 2016 water year. Bedload was measured using the Elwha bedload impact plate system (Hilldale and others, 2015). Physical bedload sampling by the U.S. Bureau of Reclamation for system calibration took place during November, 2012; March, May, and June 2013; and April 2014 at the Diversion Weir gauge (Magirl and others, 2015). Early in water year 2016 (year 5) the ...

This dataset presents 28 georeferenced orthomosaic images of the middle and lower reaches of the Elwha River. Each mosaic image was created by stitching together thousands of individual photographs that were matched based on numerous unique tie points shared by the photographs. The individual photographs were taken by a plane-mounted camera during multiple flights over the study area spanning 2012 to 2017. Because each mosaic is orthogonal to the earth's surface and is georeferenced to real-world ...

A geophysical and geological survey was conducted at the mouth of the Connecticut River from Old Saybrook to Essex, Connecticut, in September 2012. Approximately 230 linear kilometers of digital Chirp subbottom (seismic-reflection) and 234-kilohertz interferometric sonar (bathymetric and backscatter) data were collected along with sediment samples, riverbed photographs, and (or) video at 88 sites within the geophysical survey area. Sediment grab samples were collected at 72 of the 88 sampling sites, video ...

This portion of the data release presents riparian plant species abundance (percent cover) data from plots sampled in the Elwha River estuary, Washington, in 2007 and 2014. In August 2007, we established 21 vegetation plots within the study area in a stratified random fashion, with three to five plots in five of the vegetation cover types denoted in the habitat classification maps: mixed riparian forest, willow-alder forest, riparian shrub, emergent marsh/marsh-shrub transition, and dunegrass. Each plot was ...

This portion of the data release presents riparian plant species richness (number of unique taxa) data from plots sampled in the Elwha River estuary, Washington, in 2007 and 2014. In August 2007, we established 21 vegetation plots within the study area in a stratified random fashion, with three to five plots in five of the vegetation cover types denoted in the habitat classification maps: mixed riparian forest, willow-alder forest, riparian shrub, emergent marsh/marsh-shrub transition, and dunegrass. Each ...

A geophysical and geological survey was conducted at the mouth of the Connecticut River from Old Saybrook to Essex, Connecticut, in September 2012. Approximately 230 linear kilometers of digital Chirp subbottom (seismic-reflection) and 234-kilohertz interferometric sonar (bathymetric and backscatter) data were collected along with sediment samples, riverbed photographs, and (or) video at 88 sites within the geophysical survey area. Sediment grab samples were collected at 72 of the 88 sampling sites, video ...

This part of the data release contains a grid of standard deviations of bathymetric soundings within each 0.5 m x 0.5 m grid cell. The bathymetry was collected on February 1, 2011, in the Sacramento River from the confluence of the Feather River to Knights Landing. The standard deviations represent one component of bathymetric uncertainty in the final digital elevation model (DEM), which is also available in this data release. The bathymetry data were collected by the USGS Pacific Coastal and Marine ...

Streamgage levels on the Elwha River were measured from 2011 to 2016. These measurements show the height of the river's water surface, both in meters relative to the stream bed, as well as in meters relative to vertical geographic coordinates. Measurements were collected using a Global Water WL16 battery-operated vented water level logger in a hardened casing. The instrument was installed on October 17, 2011 on the left bank of the Elwha River at a power line crossing above the Elwha Surface Water Intake ...

A geophysical and geological survey was conducted at the mouth of the Connecticut River from Old Saybrook to Essex, Connecticut, in September 2012. Approximately 230 linear kilometers of digital Chirp subbottom (seismic-reflection) and 234-kilohertz interferometric sonar (bathymetric and backscatter) data were collected along with sediment samples, riverbed photographs, and (or) video at 88 sites within the geophysical survey area. Sediment grab samples were collected at 72 of the 88 sampling sites, video ...

A geophysical and geological survey was conducted at the mouth of the Connecticut River from Old Saybrook to Essex, Connecticut, in September 2012. Approximately 230 linear kilometers of digital Chirp subbottom (seismic-reflection) and 234-kilohertz interferometric sonar (bathymetric and backscatter) data were collected along with sediment samples, riverbed photographs, and (or) video at 88 sites within the geophysical survey area. Sediment grab samples were collected at 72 of the 88 sampling sites, video ...

This data release provides 15-minute data of suspended-sediment concentration and fine (less than 0.0625 mm) suspended-sediment concentration during the removal of 2 large dams on the Elwha River from September 2011 to September 2016. Data are derived from regression relations with turbidity at the USGS gaging station Elwha River at the Diversion (no.12046260).

A geophysical and geological survey was conducted at the mouth of the Connecticut River from Old Saybrook to Essex, Connecticut, in September 2012. Approximately 230 linear kilometers of digital Chirp subbottom (seismic-reflection) and 234-kilohertz interferometric sonar (bathymetric and backscatter) data were collected along with sediment samples, riverbed photographs, and (or) video at 88 sites within the geophysical survey area. Sediment grab samples were collected at 72 of the 88 sampling sites, video ...

A geophysical and geological survey was conducted at the mouth of the Connecticut River from Old Saybrook to Essex, Connecticut, in September 2012. Approximately 230 linear kilometers of digital Chirp subbottom (seismic-reflection) and 234-kilohertz interferometric sonar (bathymetric and backscatter) data were collected along with sediment samples, riverbed photographs, and (or) video at 88 sites within the geophysical survey area. Sediment grab samples were collected at 72 of the 88 sampling sites, video ...

Sediment inputs to Lake Mills, on the Elwha River, Washington, were measured from 1927 to 2016. These measurements represent the annual total sediment load, in tonnes per year, that were input into Lake Mills and partially trapped by Glines Canyon dam. The sediment was allowed to erode and be transported down-river by the removal of the Glines Canyon and Elwha dams during 2011 to 2014. The measurements were taken as part of a study investigating the river channel's morphological responses to the removal of ...

This data release contains information on computed tomography (CT) images of a vibracore that was collected by the U.S. Geological Survey in 2019. A site next to the San Lorenzo River in Henry Cowell Redwoods State Park, California, was cored to understand the history of recent vertical incision and floodplain abandonment. The core was split into 3 segments after collection. Each segment was scanned using a Geotek Rotating X-ray CT (RXCT) System and CT reconstruction was performed using Geotek ...