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 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.

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.

A summary of the maximum bloom status that was documented by the DEC HABs Program in each waterbody in each year from 2012-2018. Continuing data available at https://data.ny.gov/Energy-Environment/Harmful-Algal-Blooms-by-Waterbody-Summary-Beginnin/95my-wijm.

Measurements of Harmful Algal Blooms (HABs) in the Gulf of Mexico, Chesapeake Bay, and Great Lake regions during 2006.

This data release provides phytoplankton environmental DNA data and cyanotoxin gene qPCR data from an algal bloom at Ash River Boat Docks on Kabetogama Lake, Voyageurs National Park, Minnesota, USA (USGS site ID 482603092511801) collected in 2021 and analyzed by the commercial laboratory Jonah Ventures. We sampled cyanobacteria over a 24-hour period at Ash River Boat Docks in Kabetogama Lake, along with photosynthetically active radiation, to assess the relation between sunlight and these cyanobacteria. Sixteen environmental samples and three quality assurance replicates were collected from two sites, one at the end of the dock and one at the shoreline, between September 9, 2021 and September 10, 2021.

The objective of this research was to predict nutrient, chlorophyll-a, and associated harmful algal bloom, hypoxia, and eutrophication effects in US lakes. This research used nutrient and chlorophyll-a concentration data from the National Lakes Assessment (NLA), soil, landcover, and landscape characteristic data from LakeCat, landscape nutrient data from the National Nutrient Inventory (NNI), nutrient deposition data from the National Atmospheric Deposition Program (NADP), climate data from PRISM, landscape ecosystem data from the Earth Observatory Network (EON), and lake depth data from LAGOS and the National Hydrography Dataset (NHD). Prediction data of total nitrogen, total phosphorus, and chlorophyll-a concentrations were summarized at the catchment and lake watershed scales.