This model archive summary documents the sediment acoustic index model for suspended-sediment concentration developed to compute 15-minute suspended sediment concentration for the U.S. Geological Survey (USGS) station, San Juan River near Bluff, UT (USGS ID: 09379500) from May 2, 2018, onward. This is the first model developed for the site to compute continuous suspended sediment concentration. The methods used follow USGS guidance as referenced in relevant Technical Memoranda and USGS Techniques and Methods, book 3, chap. C5 (TM3-C5, Landers and others, 2016).

From 2008 to 2012, the U.S. Geological Survey, in cooperation with the U.S. Army Corps of Engineers, Walla Walla District, developed an acoustic backscatter surrogate (model 1.0) for estimating real-time suspended-sediment concentration and loads at Clearwater River at Spalding, ID (USGS ID: 13342500) using a horizontally-mounted 3000kHz acoustic Doppler velocity meter (ADVM). This study is a continuation of the 2008 to 2012 acoustic backscatter surrogate study using samples collected since 2015 to validate the continued use of model 1.0. Sample data collected in 2015 to 2018 show a deviation from model 1.0 when backscatter data from the ADVM, after correction for acoustic losses, is greater than 65.7 decibels. The model archive summary documents acoustic backscatter surrogate model 2.0 for the real-time calculation of suspended-sediment concentration at Clearwater River at Spalding, ID (USGS ID: 13342500). Model 2.0 is in effect from March 24, 2015 to September 30, 2019 (end of the study). The methods used in the study follow U.S. Geological Survey protocols as referenced in relevant Office of Surface Water/Office of Water Quality Technical Memoranda and U.S. Geological Survey Techniques and Methods reports.

This model archive summary documents the suspended sediment concentration (SSC) model (version 2.0) developed to compute 5-minute SSC data of the Columbia River at Port Westward, near Quincy, OR, U.S. Geological Survey (USGS) site number 14246900. The methods used follow USGS guidance as referenced in USGS Techniques and Methods, Book 3, Chap. C2 (Edwards and others, 1999); Office of Surface Water Technical Memorandum (TM) 2016.07 (USGS, 2016); Office of Water Quality TM 2016.10; USGS Techniques and Methods, book 3, chap. C5 (Landers and others, 2016); and USGS Techniques and Methods, book 3, chap. C4 (Rasmussen and others, 2009). The time series suspended sediment data will help determine the suspended sediment concentration at the site in real-time enabling science entities, managers, and others, track the movement of sediment in the Columbia River.

Model archive summary describing the development of an acoustic derived suspended sediment time series computation model. The model archive summary describes the methods and techniques used to develop the model for the Columbia River at Port Westward site – USGS site ID# 14246900. The time series suspended sediment data will help determine the suspended sediment concentration at the site in real-time enabling science entities, managers, and others, track the movement of sediment in the Columbia River.

This model archive summary documents the suspended sediment concentration (SSC) model (version 2.0) developed to compute 5-minute SSC data of the Columbia River at Port Westward, near Quincy, OR, U.S. Geological Survey (USGS) site number 14246900. The methods used follow USGS guidance as referenced in USGS Techniques and Methods, Book 3, Chap. C2 (Edwards and others, 1999); Office of Surface Water Technical Memorandum (TM) 2016.07 (USGS, 2016); Office of Water Quality TM 2016.10; USGS Techniques and Methods, book 3, chap. C5 (Landers and others, 2016); and USGS Techniques and Methods, book 3, chap. C4 (Rasmussen and others, 2009). The time series suspended sediment data will help determine the suspended sediment concentration at the site in real-time enabling science entities, managers, and others, track the movement of sediment in the Columbia River.

This model archive summary documents the suspended sand (grain sizes > 0.0625mm) concentration model developed to compute 5-minute suspended sand concentration data of the Columbia River at Port Westward, near Quincy, OR, U.S. Geological Survey (USGS) site number 14246900. The methods used follow USGS guidance as referenced in USGS Techniques and Methods, Book 3, Chap. C2 (Edwards and others, 1999); Office of Surface Water Technical Memorandum (TM) 2016.07 (USGS, 2016); Office of Water Quality TM 2016.10; USGS Techniques and Methods, book 3, chap. C5 (Landers and others, 2016); and USGS Techniques and Methods, book 3, chap. C4 (Rasmussen and others, 2009). The time series suspended sediment data will help determine the suspended sediment concentration at the site in real-time enabling science entities, managers, and others, track the movement of sediment in the Columbia River.

Model archive summary describing the development of an acoustic derived suspended sediment time series computation model. The model archive summary describes the methods and techniques used to develop the model for the Columbia River at Port Westward site – USGS site ID# 14246900. The time series suspended sediment data will help determine the suspended sediment concentration at the site in real-time enabling science entities, managers, and others, track the movement of sediment in the Columbia River.

Model archive summary describing the development of an acoustic derived suspended sediment time series computation model. The model archive summary describes the methods and techniques used to develop the model for the Columbia River at Port Westward site – USGS site ID# 14246900. The time series suspended sediment data will help determine the suspended sediment concentration at the site in real-time enabling science entities, managers, and others, track the movement of sediment in the Columbia River.

This model archive summary documents the suspended-sediment concentration (SSC) model developed to estimate 15-minute SSC at North Fork Gunnison River below Raven Gulch, U.S. Geological Survey (USGS) site number 385553107243301. The methods used follow USGS guidance as referenced in relevant Office of Surface Water/Office of Water Quality Technical Memoranda and USGS Techniques and Methods, book 3, chap. C5 (Landers and others, 2016), and USGS Techniques and Methods, book 3, chap. C4 (Rasmussen and others, 2009). A total of 456 suspended-sediment samples were collected during the calibration period (45 cross-section and 411 single-station automatic pump samples). Thirty-nine samples (18 pump samples and 21 equal-width-interval (EWI) samples) with associated streamflow and turbidity were used in the model calibration dataset. These 39 samples were collected over the range of observed streamflow and turbidity conditions. Samples used in calibration were plotted on duration curve plots for streamflow from April 24, 2015 to October 7, 2017 and turbidity from April 24, 2015 to October 7, 2017. The plots indicate that samples were collected for the observed range of conditions at the site. Suspended-sediment concentrations at this site were computed from a calibrated regression model between SSC and turbidity. Streamflow, 2 frequencies of sediment corrected backscatter (SCB) (1.5 and 3.0 megahertz (MHz)), and 2 frequencies of sediment attenuation coefficient (SAC) (1.5 and 3.0 MHz) were also examined as potential variables but did not significantly improve the model. An ordinary least squares linear regression model was developed using the ‘stats’ and ‘smwrStats’ packages in R (R Core Team, 2018). Streamflow, SCB, SAC, and turbidity were examined as potential explanatory variables for estimating SSC. A natural log transformed turbidity was selected as the best explanatory variable.

Model archive summary describing the development of an acoustic derived suspended sediment time series computation model. The model archive summary describes the methods and techniques used to develop the model for the Willamette River at Portland site – USGS site ID# 14211720. The time series suspended sediment data will help determine the suspended sediment concentration at the site in real-time enabling science entities, managers, and others, track the movement of sediment in the Lower Columbia River System.