This data release contains a national compilation of state-level qualitative and quantitative guidance for a variety of environmental indicators that are used to identify the presence of a harmful algal bloom (HAB) in freshwater ecosystems. These include qualitative guidelines based on visual or olfactory signals, as well as quantitative guidelines based on cyanotoxin concentrations, algal biomass density, and chlorophyll a concentrations. Many states in the United States have adopted guidelines based on recommendations from the U.S. Environmental Protection Agency or the World Health Organization. However, a few states have also developed their own guidelines. We are specifically focused on fresh, inland waters and we compiled guidance related to recreational and drinking water use. This data release provides guidance that is publicly available via state webpages. Additionally, states may have internal guidance and/or guidance may be available at the county or local level. This data release provides national-scale information about the indicators and associated thresholds that water resource managers use to protect humans from the potential negative effects of HABs. Note, state guidelines were queried during the summer of 2022. The attached zipped folder, State_webpages.zip, contains html and pdf files of the state webpages and posted documents used to compile the information in this data release.

Harmful algal blooms (HABs) are overgrowths of algae or cyanobacteria in water and can be harmful to humans and animals directly via toxin exposure or indirectly via changes in water quality and related impacts to ecosystems services, drinking water characteristics, and recreation. While HABs occur frequently throughout the United States, the driving conditions behind them are not well understood, especially in flowing waters. In order to facilitate future national model development and characterization of HABs, this data release publishes a synthesized and cleaned collection of HABs-related water quality and quantity data for river and stream sites across the United States. It includes nutrients, major ions, sediment, physical properties, streamflow, chlorophyll and other types of water data. This data release contains files of harmonized data from the USGS National Water Information System (NWIS). Continuous sensor data for 132 parameters (35 of which returned data) between January 1, 2005 and December 31, 2022 were downloaded from NWIS programmatically. All data were harmonized into a shared format and grouped by generic parameters; data are in files named "daily_{parameter_grp}.csv", and the "pcode_group_xwalk.csv" maps parameter codes to parameter groups. Lastly, we include a "site_metadata.csv" containing site identification and location information for all sites with water quality and quantity data, and mappings to the National Hydrography Dataset flowlines where available. This work was completed as part of the USGS Proxies Project, an effort supported by the Water Mission Area (WMA) Water Quality Processes program to develop estimation methods for PFAS, harmful algal blooms, and metals, at multiple spatial and temporal scales.

Harmful algal blooms (HABs) are overgrowths of algae or cyanobacteria in water and can be harmful to humans and animals directly via toxin exposure or indirectly via changes in water quality and related impacts to ecosystems services, drinking water characteristics, and recreation. While HABs occur frequently throughout the United States, the driving conditions behind them are not well understood, especially in flowing waters. In order to facilitate future national model development and characterization of HABs, this data release publishes a synthesized and cleaned collection of HABs-related water quality and quantity data for river and stream sites across the United States. It includes nutrients, major ions, sediment, physical properties, streamflow, chlorophyll and other types of water data. This data release contains files of harmonized data from the USGS National Water Information System (NWIS). Continuous sensor data for 132 parameters (35 of which returned data) between January 1, 2005 and December 31, 2022 were downloaded from NWIS programmatically. All data were harmonized into a shared format and grouped by generic parameters; data are in files named "daily_{parameter_grp}.csv", and the "pcode_group_xwalk.csv" maps parameter codes to parameter groups. Lastly, we include a "site_metadata.csv" containing site identification and location information for all sites with water quality and quantity data, and mappings to the National Hydrography Dataset flowlines where available. This work was completed as part of the USGS Proxies Project, an effort supported by the Water Mission Area (WMA) Water Quality Processes program to develop estimation methods for PFAS, harmful algal blooms, and metals, at multiple spatial and temporal scales.

Harmful algal blooms (HABs) are overgrowths of algae or cyanobacteria in water and can be harmful to humans and animals directly via toxin exposure or indirectly via changes in water quality and related impacts to ecosystems services, drinking water characteristics, and recreation. While HABs occur frequently throughout the United States, the driving conditions behind them are not well understood, especially in flowing waters. In order to facilitate future model development and characterization of HABs in the Illinois River Basin, this data release publishes a synthesized and cleaned collection of HABs-related water quality and quantity data for river and stream sites in the basin. It includes nutrients, major ions, sediment, physical properties, streamflow, chlorophyll and other types of water data. This data release contains files of harmonized data from the USGS National Water Information System (NWIS), the U.S. Army Corps of Engineers (USACE), the Illinois Environmental Protection Agency (IEPA), and a USGS Open File Report (OFR) containing toxin data in Illinois (Terrio and others, 2013: https://pubs.usgs.gov/of/2013/1019/pdf/ofr2013-1019.pdf). Both discrete data and continuous sensor data for 142 parameters (44 of which returned data) between October 1, 2015 and December 31, 2022 were downloaded from NWIS programmatically. All data were harmonized into a shared format (see files named data_{parameter_group}_combined.csv). The USGS NWIS data went through additional cleaning and were also grouped by generic parameters (see pcode_group_xwalk.csv to see what parameter codes are mapped to which generic parameters). Any data not from USGS NWIS were kept outside of the parameter grouping files. Additional streamflow data for select locations was retrieved from the USACE and are available in data_usace_00060_combined.csv. Additional algal toxin data provided by the IEPA and in a USGS OFR report (Terrio and others, 2013), which include some lake sites, are available in data_algaltoxins_combined.csv. We also provide collapsed datasets of daily metrics for each water quality (“generic parameter”) group of USGS NWIS data (files named daily_metrics_{parameter_group}.csv). Lastly, we include a site_metadata.csv containing site identification and location information for all sites with water quality and quantity data, and mappings to the National Hydrography Dataset flowlines where available. This work was completed as part of the USGS Proxies Project, an effort supported by the Water Mission Area (WMA) Water Quality Processes program to develop estimation methods for PFAS, harmful algal blooms, and metals, at multiple spatial and temporal scales.

Harmful algal blooms (HABs) are overgrowths of algae or cyanobacteria in water and can be harmful to humans and animals directly via toxin exposure or indirectly via changes in water quality and related impacts to ecosystems services, drinking water characteristics, and recreation. While HABs occur frequently throughout the United States, the driving conditions behind them are not well understood, especially in flowing waters. In order to facilitate future model development and characterization of HABs in the Illinois River Basin, this data release publishes a synthesized and cleaned collection of HABs-related water quality and quantity data for river and stream sites in the basin. It includes nutrients, major ions, sediment, physical properties, streamflow, chlorophyll and other types of water data. This data release contains files of harmonized data from the USGS National Water Information System (NWIS), the U.S. Army Corps of Engineers (USACE), the Illinois Environmental Protection Agency (IEPA), and a USGS Open File Report (OFR) containing toxin data in Illinois (Terrio and others, 2013: https://pubs.usgs.gov/of/2013/1019/pdf/ofr2013-1019.pdf). Both discrete data and continuous sensor data for 142 parameters (44 of which returned data) between October 1, 2015 and December 31, 2022 were downloaded from NWIS programmatically. All data were harmonized into a shared format (see files named data_{parameter_group}_combined.csv). The USGS NWIS data went through additional cleaning and were also grouped by generic parameters (see pcode_group_xwalk.csv to see what parameter codes are mapped to which generic parameters). Any data not from USGS NWIS were kept outside of the parameter grouping files. Additional streamflow data for select locations was retrieved from the USACE and are available in data_usace_00060_combined.csv. Additional algal toxin data provided by the IEPA and in a USGS OFR report (Terrio and others, 2013), which include some lake sites, are available in data_algaltoxins_combined.csv. We also provide collapsed datasets of daily metrics for each water quality (“generic parameter”) group of USGS NWIS data (files named daily_metrics_{parameter_group}.csv). Lastly, we include a site_metadata.csv containing site identification and location information for all sites with water quality and quantity data, and mappings to the National Hydrography Dataset flowlines where available. This work was completed as part of the USGS Proxies Project, an effort supported by the Water Mission Area (WMA) Water Quality Processes program to develop estimation methods for PFAS, harmful algal blooms, and metals, at multiple spatial and temporal scales.

Listing of harmful algal bloom occurrences by waterbody. Data from 2012-2018 available at https://data.ny.gov/Energy-Environment/Harmful-Algal-Bloom-Statewide-Occurrence-Summary-2/qtg2-hjth.

Blooms of nuisance and toxic cyanobacteria, referred to as cyanobacteria harmful algal blooms (cHABs), occur seasonally in Saginaw Bay, Lake Huron, and pose a threat to human health, affect the quality of life, and significantly degrade the ecosystem. NOAA Great Lakes Environmental Research Laboratory and the Cooperative Institute for Great Lakes Research (CIGLR), University of Michigan, started regular water quality monitoring of Saginaw Bay, Lake Huron in 2012. Since that time the monitoring effort has expanded to incorporate additional parameters and sample locations. Physical, chemical, and biological water quality data were collected during repeated sampling trips to a set of stations before, during, and after HAB events (from May - October). Data for these discrete sampling events include: Secchi disk depth, Conductivity, Temperature and Depth (CTD), CTD specific conductivity, CTD beam attenuation, CTD beam transmission, CTD dissolved oxygen, CTD photosynthetically active radiation, turbidity, particulate microcystin, dissolved microcystin, extracted phycocyanin, extracted chlorophyll-a, total phosphorus, total dissolved phosphorus, soluble reactive phosphorus, ammonia, nitrate + nitrite, urea, particulate organic carbon, particulate organic nitrogen, dissolved organic carbon, chromophoric dissolved organic material absorbance at 400 nm, total suspended solids, and volatile suspended solids. The bulk water quality parameters were analyzed via established techniques and procedures for routine water quality monitoring and analysis (APHA 1992, 1998, 2017). This research was funded by the Great Lakes Restoration Initiative (GLRI) to support the projects “Decision Support Tools to Link Predictions to HABs and Source Water Protection”, Synthesis Observation and Response (SOAR), and Real-time Environmental Coastal Observation Network (ReCON).