HAB Monitoring and Trends
A principal responsibility of the U.S. Environmental Protection Agency and National Oceanic and Atmospheric Administration (NOAA) is to provide monitoring and forecasting data on HABs across the United States. This page describes the resources users can access to find information on real-time and historical data in HABs across the country. Note that all of these resources provide estimated HAB biomass derived from satellite images of water color. No satellites can currently provide real-time data on toxin concentrations because satellites cannot detect toxins.
On this page:
- Near Real-Time Satellite Monitoring Data
- Status of HABs in the Nation’s Waters
- Temporal Trends in HABs
- Trends in Algal Biomass, Algal Composition and Algal Toxins
Near Real-Time Satellite Monitoring Data
Near real-time data on HABs are provided through a variety of sources. The EPA provides real-time data on cyanobacterial algal blooms for a large population of lakes in the U.S. via the Cyanobacteria Assessment Network (CyAN) mobile and desktop applications:
The same data are also made available for individual lakes in the CyAN network through the EPA's How’s My Waterway application. Users can navigate to their waters of interest and find near real-time cyanobacteria HAB data available from CyAN.
In the future, the EPA will be working to improve the resolution of the satellite data available so it can provide links to near real-time HAB information for even more lakes across the nation.
NOAA provides similar near real-time satellite derived data on algal blooms in portions of the Great Lakes, Chesapeake Bay, Albemarle Sound, NC, Lake Pontchartrain, LA, Lake Okeechobee, FL, and Southwest Florida:
In Lake Erie specifically:
And for coastal ecosystems around the US:
In addition to these sites, some states also serve near real-time algal biomass or HAB data including, for example:
- California: My Water Quality: California Harmful Algal Blooms (HABs) Portal
- Florida: Where Are HABs?
- Oregon: Satellite Estimates of Cyanobacteria in Oregon Lakes and Reservoirs (serves CyAN data for Oregon specifically)
Status of HABs in the Nation’s Waters
The National Aquatic Resource Surveys are collaborative programs between the EPA, states, and Tribes designed to assess the quality of the nation's coastal waters, lakes and reservoirs, rivers and streams, and wetlands using a statistical survey design. The NARS provide critical, groundbreaking, and nationally-consistent data on the nation's waters and this includes data on HABs and HAB toxins.
The NARS are made up of four individual surveys implemented on a rotating basis. You can access HAB data highlights, including the percent of waterbodies with detectable toxins, the percent exceeding recreational HAB toxin criteria levels and the percent with excess chlorophyll dominated by cyanobacteria at each of the individual survey websites:
- National Coastal Condition Assessment
- National Lakes Assessment
- National Rivers and Streams Assessment
- National Wetland Condition Assessment
Temporal Trends in HABs
In addition to near real-time data, long-term trends in HAB data are also provided by the EPA for freshwaters.
Trends for the individual lakes included in the CyAN network are provided through the EPA's EnviroAtlas. In that application, users can find long-term trends in the extent and frequency of HABs for lakes of interest in the CyAN network by navigating to the lake of interest and selecting the cyanobacteria information:
- EnviroAtlas
- Fact Sheet: CyAN Extent and Bloom Frequency, EnviroAtlas National (pdf) (August 2022)
Cyanobacterial HAB trends synthesized across all lakes in the U.S. are also valuable and these are provided as a national snapshot by the EPA's Report on the Environment, where one can view trends in HAB statistics (weekly occurrence, area covered, and frequency of detections) over time nationally and by major region of the U.S. since 2008 for lakes in the CyAN network.
In the future, the EPA will be working to improve the resolution of the satellite data available so it can provide links to temporal trends in HABs for even more lakes across the US.
Trends in Algal Biomass, Algal Composition and Algal Toxins
The Water Quality Portal (WQP) stores water quality data from generators across the US (e.g., states, Tribes, territories, other federal agencies). These data include algal biomass, taxonomic composition and toxins. Data can be extracted and used to assess trends over time at individual waterbody, regional, and national scales. Access these data by visiting the Water Quality Portal:
The EPA is working to develop tools to visualize trends in WQP HAB data across the nation. Those tools will be made available through this site when they are completed.