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2022 Statewide Harmful Algal Bloom Program

The 2022 Harmful Algal Bloom Program comprises two parts: Routine Monitoring and Event Response.  Routine Monitoring targets public-water-supply intakes in Illinois lakes, streams, or Lake Michigan; lake beaches; or Lake Michigan nearshore areas.  Event Response investigates potential cyanobacteria blooms in lakes or in streams where blooms may threaten public health.  All toxin samples are sent to the Illinois EPA Division of Laboratories for analysis.  Beach samples are analyzed for the toxin microcystin.  Source water intakes are analyzed for three additional toxins: cylindrospermopsin, anatoxin-a, and saxitoxin. In some situations, additional samples for cyanobacteria taxonomy and enumeration may be collected and sent to a private contractor.  

Routine Monitoring

Routine Monitoring occurs on the following waterbodies:

  1. Fox River (Northern Illinois)
    Illinois EPA or contractual staff collect a sample approximately every six weeks at each of four Fox River sites, during June through October.

  2. Public-Water-Supply Intakes in Streams
    Illinois EPA staff collect four samples at each of the ten following sites near public-water-supply intakes in streams, during May through October.
    Salt Fork Vermilion River 
    Little Wabash River
    Skillet Fork
    Illinois River
    Fox River
    Kankakee River
    Mississippi River
    Shoal Creek 

  3. Nearshore Areas in Lake Michigan
    Illinois EPA collects three microcystin sample from two harbor sites and five Nearshore sites in Lake Michigan during April through November.

  4. Public-Water-Supply Intakes in Lake Michigan
    Illinois EPA collects three samples at each of five Lake Michigan intakes during April through November. Sampling frequency and number of samples depend on weather conditions.

  5. Beaches -Ambient Lake Monitoring Program
    Illinois EPA collects between one to three samples at beaches in four northern-Illinois lakes, three central-Illinois lakes, and two southern-Illinois lakes (Table 1). 

  6. Public-Water-Supply Intakes - Ambient Lake Monitoring Program
    Illinois EPA collects one sample per month during June, July, August/September, and October near public-water-supply intakes in eight central-Illinois lakes and eight southern-Illinois lakes (Table 1).

  7. Beaches - Lake County Health Department
    During 05/30/2022 through 09/05/2022, the Lake County Health Department collects a sample approximately every two weeks at a beach in each of fourteen lakes and one stream(Table 1). 

Table 1. Routine Monitoring at Illinois Lakes

Region Lake Name County IEPA Lake Code Sampling Focus

 Northern Illinois

Round Lake


Long Lake
​Woods Creek Lake
​Lake Le Aqua Na




Central Illinois ​

Canton Lake



​Public Water Supplies

​Lake Decatur
​Lake Glenn Shoals
​Lake Mattoon
​Otter Lake
​Lake Jacksonville

Beach, Public Water Supply​
​Lake Sara
​Lake Lou Yaeger

​Southern Illinois
​East Fork Lake

​Public Water Supply

​ ​
​Fairfield Side Channel Reservoir
​Nashville City Reservoir
​Governor Bond Lake
​Highland Silver
​Lake Coulterville
​Salem Reservoir
​Vandalia Lake
​Beach, Public Water Supply
​Borah Lake

Lake County

Lake Barrington


​ ​
​ ​

Lake Catherine Lake
​Channel Lake
Lake ​RTI
Countryside Lake ​Lake RGQ
​Dunns Lake ​Lake ​VTH
​Fish Lake
​Lake ​VTK
​Island Lake
​Lake ​RTZI
​Loch Lomond ​Lake ​RGU
​Long Lake ​Lake ​RTJ
​Slocum Lake
​Lake ​RTP
​Tower Lake
​Valley Lake

Event Response

Event Response investigates credible reports of a potential cyanobacteria bloom. Credible report means direct observation by Illinois EPA staff or observations and pictures submitted by the public to Illinois EPA via our Bloom Report Form.

  1. Direct Observation 
    Illinois EPA field staff collect a sample for microcystin, when they observe a cyanobacteria bloom in a lake or stream during routine sampling for resource quality. Other toxins may be collected on a per-case basis.

  2. Response via Bloom Report Form 
    Illinois EPA investigates reported suspected cyanobacteria blooms dependent on availability of resources. We give priority to publicly owned lakes.

Illinois EPA applies a preliminary test to screen Event Response samples typically for the toxin, microcystin, but may include other toxins. When a toxin exceeds relevant thresholds for recreation or drinking water, Illinois EPA notifies appropriate lake-management entities. Illinois EPA may perform follow-up monitoring based on availability of resources.

Program Improvements

In October 2020, the U.S. Environmental Protection Agency awarded a grant ($270,626) to Illinois EPA to improve the Illinois EPA Harmful Algal Bloom Program. Over the next three years Illinois EPA intends to expand public education and awareness of cyanobacteria blooms, improve our ability to respond to blooms, and provide more timely access to available data to help protect human health. Some specific activities include, but are not limited to:

  1. Virtual Workshops on Harmful Cyanobacteria Blooms
    Illinois EPA is working with PhycoTech, Inc. to conduct two of the remaining six virtual workshops. Two workshops have been conducted each year starting in 2020.   These workshops help train and educate Illinois EPA staff and other professionals how to identify a potential  cyanobacteria bloom, how to collect toxin samples, how to pack and ship samples to the laboratory for analysis, and how to pack and ship samples to PhycoTech, Inc. for identification and enumeration.

  2. Update the Illinois EPA Webpage
    Periodically, Illinois EPA will update the program webpage to improve content and accessibility of data and information. 

  3. Update Standard Operating Procedures for Collecting Toxin Samples
    Illinois EPA has updated the standard operating procedure for collecting cyanobacteria toxins in lakes and streams.

  4. Collaborate with the Illinois Department of Public Health
    The Illinois EPA is working with the Illinois Department of Public Health to create social-media content about cyanobacteria in Illinois waters. This content readily provides relevant information to a wide audience.

  5. Create Manual for Responding to Cyanobacteria Blooms
    Illinois EPA is in the process of developing a manual to prepare for a large-scale cyanobacteria bloom. This document will include, but is not limited to, a discussion of toxin-level thresholds of concern, a contact list of relevant personnel, toxin-collection guidelines, and examples of news releases and other appropriate ways to alert the public (e.g., posted warnings at sites).

Historical HAB Information