This dataset allows the user to explore the potential impacts of various environmental and anthropogenic drivers on observed growing season total phosphorus concentrations in lakes and streams across the United States.

Total Phosphorus composite monitoring data set for 52 lakes.

Phosphorus, nitrogen, chloride, and suspended-sediment loads, in 24 U.S. tributaries of the Great Lakes, were estimated using U.S. Geological Survey (USGS) data from the Great Lakes Restoration Initiative (GLRI) monitoring program for the period Oct 2010 through Sept 2023 (USGS water years 2011-23). Specific water-quality constituents include total phosphorus, orthophosphate, particulate phosphorus, total nitrogen, nitrate plus nitrite, ammonium plus ammonia, chloride, and suspended sediment. Concentrations and loads, including actual and flow-normalized estimates, were estimated with Weighted Regression on Time, Discharge, and Season (WRTDS). Results are reported at daily and annual time steps in this data release and via an interactive web application (https://rconnect.usgs.gov/glritrends). This data release is an update of a previous version for water years 2011-20. Major changes include the addition of data from water years 2021-23 and the addition of chloride to the constituents.

Phosphorus, nitrogen, and suspended-sediment loads, in 24 U.S. tributaries of the Great Lakes, were calculated using U.S. Geological Survey (USGS) data from the Great Lakes Restoration Initiative (GLRI) monitoring program for the period Oct 2010 through Sept 2020 (USGS water years 2011–2020). Total phosphorus, orthophosphate, particulate phosphorus, total nitrogen, nitrate plus nitrite, ammonium plus ammonia, and suspended-sediment loads and changes in loads were determined by applying a weighted regression approach called WRTDS (Weighted Regression on Time, Discharge, and Season). The load results represent the total mass of nitrogen, phosphorus, and suspended sediment exported downstream at each tributary site. Daily loads were estimated using the WRTDS method with Kalman filtering. To determine the change in loads between the first and last water year in record, the annual load results were flow-normalized to standardize among years with varying flow dynamics. Three primary data tables are provided that describe phosphorus, nitrogen, and suspended-sediment conditions at 24 tributaries across the U.S. Great Lakes watershed: (1) annual results, (2) daily results, and (3) changes results. The annual table is organized by USGS water year (defined as Oct 1–Sept 30). The annual and daily tables also include time-weighted mean concentrations, mean discharge, and yield estimates, the latter being calculated by dividing loads by watershed areas. Descriptions for data tables are provided in the DataDictionary.csv file. Results are also displayed in an interactive web application (https://rconnect.usgs.gov/glritrends). This data release also contains a model archive. The “model_code.zip” file contains the R code and input data to run the models, generate the results, and display the results on a shiny application. The Readme.md file includes instructions of how to run the model and descriptions of all inputs, model arguments, and outputs. Each model (saved as an eList) contains the input data (USGS station information (i.e., site information), daily discharge, and water sample data), model parameters, estimated values, and bootstrapped results. All eLists are archived in the “model_archive” folder, which is organized by sample dataset (i.e., allsamples and midsamples) and are named with the parameter and station number (e.g., NH4_04024000.RData). The RData files used in the shiny application are archived in the “shinydata” folder.

Phosphorus, nitrogen, and suspended-sediment loads, in 24 U.S. tributaries of the Great Lakes, were calculated using U.S. Geological Survey (USGS) data from the Great Lakes Restoration Initiative (GLRI) monitoring program for the period Oct 2010 through Sept 2020 (USGS water years 2011–2020). Total phosphorus, orthophosphate, particulate phosphorus, total nitrogen, nitrate plus nitrite, ammonium plus ammonia, and suspended-sediment loads and changes in loads were determined by applying a weighted regression approach called WRTDS (Weighted Regression on Time, Discharge, and Season). The load results represent the total mass of nitrogen, phosphorus, and suspended sediment exported downstream at each tributary site. Daily loads were estimated using the WRTDS method with Kalman filtering. To determine the change in loads between the first and last water year in record, the annual load results were flow-normalized to standardize among years with varying flow dynamics. Three primary data tables are provided that describe phosphorus, nitrogen, and suspended-sediment conditions at 24 tributaries across the U.S. Great Lakes watershed: (1) annual results, (2) daily results, and (3) changes results. The annual table is organized by USGS water year (defined as Oct 1–Sept 30). The annual and daily tables also include time-weighted mean concentrations, mean discharge, and yield estimates, the latter being calculated by dividing loads by watershed areas. Descriptions for data tables are provided in the DataDictionary.csv file. Results are also displayed in an interactive web application (https://rconnect.usgs.gov/glritrends). This data release also contains a model archive. The “model_code.zip” file contains the R code and input data to run the models, generate the results, and display the results on a shiny application. The Readme.md file includes instructions of how to run the model and descriptions of all inputs, model arguments, and outputs. Each model (saved as an eList) contains the input data (USGS station information (i.e., site information), daily discharge, and water sample data), model parameters, estimated values, and bootstrapped results. All eLists are archived in the “model_archive” folder, which is organized by sample dataset (i.e., allsamples and midsamples) and are named with the parameter and station number (e.g., NH4_04024000.RData). The RData files used in the shiny application are archived in the “shinydata” folder.

Raw data associated with EPA 2018-2019 National Rivers and Streams Assessment Diatom Diversity and Phosphorus Study. This dataset is associated with the following publication: Yuan, L., R. Mitchell, A. Pollard, C. Nietch, E. Pilgrim, and N. Smucker. Understanding the effects of phosphorus on diatom richness in rivers and streams using taxon–environment relationships. FRESHWATER BIOLOGY. Blackwell Publishing, Malden, MA, USA, 68(3): 473-486, (2023).

The Archive.zip data set contains R source code and inputs and selected outputs associated with regression analyses used to estimate total phosphorus loads for selected sites on Great Lakes tributaries for water years 2014–2018

This data release contains the R source code, inputs, and selected outputs associated with the turbidity-based regression models used to estimate total phosphorus concentrations and loads for the Missouri River at St. Joseph and Hermann, Missouri, for water years 2008–22. Additionally, the R source code, inputs, and selected outputs for LOADEST models used to estimate daily total phosphorus loads for the study period are included, as these loads were used for days when turbidity data was unavailable.

This data release contains the R source code, inputs, and selected outputs associated with the turbidity-based regression models used to estimate total phosphorus concentrations and loads for the Missouri River at St. Joseph and Hermann, Missouri, for water years 2008–22. Additionally, the R source code, inputs, and selected outputs for LOADEST models used to estimate daily total phosphorus loads for the study period are included, as these loads were used for days when turbidity data was unavailable.

Nutrient and soil runoff from agricultural fields in the Upper East River basin contribute to eutrophication in downstream waters like Lake Michigan. Phosphorus is often the limiting nutrient in freshwater ecosystems and the binding of dissolved phosphorus to suspended sediment can reduce its bioavailability. These data provide information about what size particles are binding phosphorus and how the proportion of total phosphorus that is dissolved changes as the phosphorus is transported from the field through the stream network during runoff events. Samples were collected for analysis in 2022 and 2023. Information about management of Wisconsin Waterway 3 was also collected from 2020-2023 and is included in this data release.