The Indiana Department of Environmental Management (IDEM), the Indiana Department of Natural Resources (DNR), the Indiana State Department of Health (ISDH), and the Board of Animal Health (BOAH) are working to provide information about blue-green algae, also known as cyanobacteria, in our lakes.

Algae are commonly found in Indiana lakes and streams without concern, however the concentrated presence of blue-green algae can be linked to some adverse health effects. Factors promoting algal growth include sunlight, warm weather, low turbulence, and nutrient sources, such as phosphorus and nitrogen. Phosphorous is particularly important in fueling cyanobacteria growth. Often nutrient inputs come from nonpoint source pollution, but fortunately, there are many ways to reduce or stop nonpoint source pollution, many of which are simple things we can do right in our own backyards.

Not taken seriously, blue-green algae can destroy a lake community with a long recovery period. To be good stewards for sustaining our lakes, it is important to control the common sources of nonpoint source pollution in Indiana, which include:

  • animal production operations and feedlots;
  • agricultural activities;
  • stream bank and shoreline erosion;
  • timber harvesting;
  • land development;
  • on-site sewage disposal units;
  • solid waste disposal landfills;
  • transportation-related facilities;
  • coal mining;
  • oil and gas production;
  • non-energy mineral extraction; and,
  • atmospheric deposition.

Blue-green Algae Stories:

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