The U.S. Geological Survey (USGS) developed a systematic, quantitative approach to prioritize candidate basins that can support the assessment and forecasting objectives of the major USGS water science programs. Candidate basins were the level-4 hydrologic units (HUC4) with some of the smaller HUC4s being combined (hereafter referred to as modified HUC4 basins). Candidate basins for the contiguous United States (CONUS) were grouped into 18 hydrologic regions. Thirty-three geospatial variables representing land use, climate change, water use, water-balance components, streamflow alteration, fire risk, and ecosystem sensitivity were initially considered to assist in ranking candidate basins for study. The two highest ranking candidate basins in each of the 18 regions were identified as semi-finalists for selection as “Integrated Water Science Basins.” The initial 33 geospatial variables are included within this data release. Also included in this data release are the polygon layers of the modified HUC4 basins and the hydrologic regions used for the analyses and a separate data dictionary to define the variables.

The U.S. Geological Survey (USGS) developed a systematic, quantitative approach to prioritize candidate basins that can support the assessment and forecasting objectives of the major USGS water science programs. Candidate basins were the level-4 hydrologic units (HUC4) with some of the smaller HUC4s being combined (hereafter referred to as modified HUC4 basins). Candidate basins for the contiguous United States (CONUS) were grouped into 18 hydrologic regions. Thirty-three geospatial variables representing land use, climate change, water use, water-balance components, streamflow alteration, fire risk, and ecosystem sensitivity were initially considered to assist in ranking candidate basins for study. The two highest ranking candidate basins in each of the 18 regions were identified as semi-finalists for selection as “Integrated Water Science Basins.” The initial 33 geospatial variables are included within this data release. Also included in this data release are the polygon layers of the modified HUC4 basins and the hydrologic regions used for the analyses and a separate data dictionary to define the variables.

Water availability for human and ecosystem needs is a function of both water quantity and water quality, as described in the U.S. Geological Survey (USGS) Water Science Strategy (Evenson and others, 2013). Recently, a quantitative approach to prioritize candidate watersheds for monitoring investment was developed to understand changes in water availability and advance the objectives of new USGS programs (Van Metre and others, 2020). In this study design, the contiguous United States (CONUS) was divided into 18 regions (referred to here as “hydrologic regions” or “HRs”) with relatively homogeneous hydrologic drivers and processes to represent the wide diversity in conditions that exist across the CONUS. The gap analysis focused on prioritizing new capabilities beyond the current USGS science in discharge and constituent concentration trends to develop integrated capabilities for assessing and modeling of the water-quality drivers of aquatic ecosystem health. Water availability can be limited by various water-quality parameters such as temperature, salinity, excess nutrients, suspended sediment, geogenic constituents, and other contaminants of emerging concern (CECs) depending on water sources and human or ecosystem needs (Stanton and others, 2017). This data release contains more than 100 geospatial variables summarized for each watershed at the Hydrologic Unit level 4 (HUC4) that were used to prioritize watersheds targeted for USGS research. Additionally, the data release includes the polygon layers of the modified HUC4 watersheds and the hydrologic regions used for the analyses.

Water availability for human and ecosystem needs is a function of both water quantity and water quality, as described in the U.S. Geological Survey (USGS) Water Science Strategy (Evenson and others, 2013). Recently, a quantitative approach to prioritize candidate watersheds for monitoring investment was developed to understand changes in water availability and advance the objectives of new USGS programs (Van Metre and others, 2020). In this study design, the contiguous United States (CONUS) was divided into 18 regions (referred to here as “hydrologic regions” or “HRs”) with relatively homogeneous hydrologic drivers and processes to represent the wide diversity in conditions that exist across the CONUS. The gap analysis focused on prioritizing new capabilities beyond the current USGS science in discharge and constituent concentration trends to develop integrated capabilities for assessing and modeling of the water-quality drivers of aquatic ecosystem health. Water availability can be limited by various water-quality parameters such as temperature, salinity, excess nutrients, suspended sediment, geogenic constituents, and other contaminants of emerging concern (CECs) depending on water sources and human or ecosystem needs (Stanton and others, 2017). This data release contains more than 100 geospatial variables summarized for each watershed at the Hydrologic Unit level 4 (HUC4) that were used to prioritize watersheds targeted for USGS research. Additionally, the data release includes the polygon layers of the modified HUC4 watersheds and the hydrologic regions used for the analyses.

Water availability for human and ecosystem needs is a function of both water quantity and water quality, as described in the U.S. Geological Survey (USGS) Water Science Strategy (Evenson and others, 2013). Recently, a quantitative approach to prioritize candidate watersheds for monitoring investment was developed to understand changes in water availability and advance the objectives of new USGS programs (Van Metre and others, 2020). In this study design, the contiguous United States (CONUS) was divided into 18 regions (referred to here as “hydrologic regions” or “HRs”) with relatively homogeneous hydrologic drivers and processes to represent the wide diversity in conditions that exist across the CONUS. The gap analysis focused on prioritizing new capabilities beyond the current USGS science in discharge and constituent concentration trends to develop integrated capabilities for assessing and modeling of the water-quality drivers of aquatic ecosystem health. Water availability can be limited by various water-quality parameters such as temperature, salinity, excess nutrients, suspended sediment, geogenic constituents, and other contaminants of emerging concern (CECs) depending on water sources and human or ecosystem needs (Stanton and others, 2017). This data release contains more than 100 geospatial variables summarized for each watershed at the Hydrologic Unit level 4 (HUC4) that were used to prioritize watersheds targeted for USGS research. Additionally, the data release includes the polygon layers of the modified HUC4 watersheds and the hydrologic regions used for the analyses.

This product consists of 29 datasets of tabular data and associated metadata for watershed characteristics of 1,530 study sites of the Surface Water Trends (SWT) project of the U.S. Geological Survey’s (USGS) National Water Quality Program (NWQP). The project is conducting national studies of trends in water quality of streams and rivers for periods ranging from 10 to 40 years, between 1972 and 2012. The data here include both static and time-series characteristics. Static data include primarily physical characteristics which have changed little over this period, such as geology, soils, and topography. Time-series data represent characteristics which may or may not have changed over time, such as land use, agricultural practices, precipitation, hydrologic modifications, atmospheric deposition, and population changes.

This product consists of 29 datasets of tabular data and associated metadata for watershed characteristics of 1,530 study sites of the Surface Water Trends (SWT) project of the U.S. Geological Survey’s (USGS) National Water Quality Program (NWQP). The project is conducting national studies of trends in water quality of streams and rivers for periods ranging from 10 to 40 years, between 1972 and 2012. The data here include both static and time-series characteristics. Static data include primarily physical characteristics which have changed little over this period, such as geology, soils, and topography. Time-series data represent characteristics which may or may not have changed over time, such as land use, agricultural practices, precipitation, hydrologic modifications, atmospheric deposition, and population changes.

Chloride data used to assess trends over time, using both USGS data for trends in loads and USEPA NRSA data used to assess trends in concentrations. Citation information for this dataset can be found in the EDG's Metadata Reference Information section and Data.gov's References section.

Chloride data used to assess trends over time, using both USGS data for trends in loads and USEPA NRSA data used to assess trends in concentrations. Citation information for this dataset can be found in the EDG's Metadata Reference Information section and Data.gov's References section.

The U.S. Geological Survey (USGS), in cooperation with the Missouri Department of Natural Resources (MDNR), collects data pertaining to the surface-water resources of Missouri. These data are collected as part of the Missouri Ambient Water-Quality Monitoring Network (AWQMN) and are stored and maintained by the USGS National Water Information System (NWIS) database. These data constitute a valuable source of reliable, impartial, and timely information for developing an improved understanding of the water resources of the State. Water-quality data collected between 1993 and 2017 were analyzed for long term trends and the network was investigated to identify data gaps or redundant data to assist MDNR on how to optimize the network in the future. This is a companion data release product to the Scientific Investigation Report: Richards, J.M., and Barr, M.N., 2021, General water-quality conditions, long-term trends, and network analysis at selected sites within the Ambient Water-Quality Monitoring Network in Missouri, water years 1993–2017: U.S. Geological Survey Scientific Investigations Report 2021–5079, 75 p., https://doi.org/10.3133/sir20215079. The following selected tables are included in this data release in compressed (.zip) format: AWQMN_EGRET_data.xlsx -- Data retrieved from the USGS National Water Information System database that was quality assured and conditioned for network analysis of the Missouri AWQMN AWQMN_R-QWTREND_data.xlsx -- Data retrieved from the USGS National Water Information System database that was quality assured and conditioned for analysis of flow-weighted trends for selected sites in the Missouri AWQMN AWQMN_R-QWTREND_outliers.xlsx -- Data flagged as outliers during analysis of flow-weighted trends for selected sites in the Missouri AWQMN AWQMN_R-QWTREND_outliers_quarterly.xlsx -- Data flagged as outliers during analysis of flow-weighted trends using a simulated quarterly sampling frequency dataset for selected sites in the Missouri AWQMN AWQMN_descriptive_statistics_WY1993-2017.xlsx -- Descriptive statistics for selected water-quality parameters at selected sites in the Missouri AWQMN