This file contains estimates of long-term mean annual suspended-sediment loads for western Oregon and northwestern California as predicted by the USGS SPARROW model (Wise, 2018). This application of the SPARROW model used the NHDPlus Version 2 as a hydrologic framework and represented 2012 conditions.

The U.S. Geological Survey's (USGS) SPAtially Referenced Regressions On Watershed attributes (SPARROW version 2_10) model was used to aid in the interpretation of monitoring data and simulate streamflow and water-quality conditions in streams across the Pacific Region of the Unites States. SPARROW is a hybrid empirical/process-based mass balance model that can be used to estimate the major sources and environmental factors that affect the long-term supply, transport, and fate of contaminants in streams. The spatially explicit model structure is defined by a river reach network coupled with contributing catchments. The model is calibrated by statistically relating watershed sources and transport-related properties to monitoring-based water-quality load estimates. This USGS data release includes input and output files associated with 2012 SPARROW simulations of streamflow, total nitrogen, total phosphorus and suspended sediment load in streams of the Pacific region. Model construction, calibration and results are described in Wise (2019, https://doi.org/10.3133/sir20195112). First posted - January 6, 2020(available from author) Revised - June 08, 2020

The U.S. Geological Survey's (USGS) SPAtially Referenced Regression On Watershed attributes (SPARROW) model was used to aid in the interpretation of monitoring data and simulate streamflow and water-quality conditions in streams across the Southwestern Region of the Unites States. SPARROW is a hybrid empirical/process-based mass balance model that can be used to estimate the major sources and environmental factors that affect the long-term supply, transport, and fate of contaminants in streams. The spatially explicit model structure is defined by a river reach network coupled with contributing catchments. The model is calibrated by statistically relating watershed sources and transport-related properties to monitoring-based water-quality load estimates. This USGS data release includes input and output files associated with 2012 SPARROW simulations of streamflow, total nitrogen, total phosphorus and suspended-sediment load in streams of the Southwestern region. Model construction, calibration and results are described in Wise, Anning, and Miller (2019, https://doi.org/10.3133/sir20195106.

Suspended-sediment transport is a critical element governing the geomorphology of tidal marshes and estuaries. Marsh elevation, relative to sea level, is maintained by both organic material and the deposition of inorganic sediment. Additionally, horizontal marsh extent is altered by lateral erosion and accretion. In wetlands within and near Grand Bay National Estuarine Research Reserve, parts of the salt marsh are eroding relatively rapidly. To understand the connection between sediment fluxes and these processes, the U.S. Geological Survey made oceanographic and water-quality measurements from August 2, 2016, to January 28, 2017, to quantify suspended-sediment concentration and sediment transport in tidal channels and open embayments in and near Grand Bay National Estuarine Research Reserve.

This data release contains mean-annual total nitrogen (TN) loads predicted by a SPARROW model for individual stream and shoreline reaches in the Chesapeake watershed as defined by NHDPlus, a 1:100,000 scale representation of stream hydrography built upon the National Hydrography Dataset (NHD) (Horizon Systems, 2010). Also included are the input variables required to execute the model, including landscape characteristics, nutrient inputs to land, and calibration data from water quality monitoring stations. Further details on model construction and results are described in Ator (2011, https://doi.org/10.3133/sir20115167).

Results of statistical analyses of nontidal and tidal station measurements of suspended sediment concentrations in the Chesapeake Bay and watershed, collected from 1984-2021 by Chesapeake Bay Program and partners and the U.S. Geological Survey. Original measurements were retrieved from online data repositories.

The U.S. Geological Survey’s SPAtially Referenced Regression On Watershed attributes (SPARROW) for the Southeastern United States was used to simulate changes in total nitrogen, total phosphorus and suspended sediment load in streams under two scenarios: (1) where all forests are urbanized and (2) where all forests are urbanized and runoff is adjusted based on a non-forested landscape. This data release includes model input not published with the original model and used for scenario simulations, and model output for total nitrogen, total phosphorus, and suspended sediment under baseline conditions, scenario (1), and scenario (2). Original model input, output, and shapefiles are available (Roland and Hoos, 2020, https://https://doi.org/10.5066/p9a682gw) and original model development is described in Hoos and Roland (2019, https://doi.org/10.3133/sir20195135).

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.

Model archive summary (MAS) describing the development of a suspended-sediment concentration (SSC) surrogate regression model for the Hookton Slough near Loleta, CA water quality station (USGS site ID# 404038124131801). A continuous 15-minute SSC record was computed using this regression model for the period of record (03-04-2016 to 09-10-2019). The computed SSC record can be found on NWIS Web at https://waterdata.usgs.gov/ca/nwis/uv?site_no=404038124131801. The SSC record was used to assess ambient SSC conditions, the availability of suspended sediment to support surface deposition and elevation gain in adjacent salt marshes, and to characterize salt marsh resiliency to climate change impacts in Humboldt Bay, CA.

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.