People who use Indiana's lakes and reservoirs for recreation should be aware that blue-green algae blooms have the potential to cause health problems in humans and animals.

Blue-green algae blooms are a seasonal occurrence in some Indiana waters, fueled by summer heat, sunlight and fertilizer runoff from lawns and farms. Drought and low water levels in lakes and reservoirs can increase blue-green algae quantities and/or toxins.

Some blue-green algae produce toxins that can cause rashes, skin and eye irritation, nausea, stomach aches, and tingling fingers and toes. People who experience any of these symptoms after boating or swimming should seek medical attention.

Dogs and other animals are particularly vulnerable to blue-green algae because they may drink the contaminated water or swallow the algae as they clean their coats.

Two dogs died and two others were sickened earlier this week after swimming in a cove at Salamonie Lake. Symptoms and circumstances suggest blue-green algae toxicity may have been the cause.

Boaters, swimmers and dog owners should:

  • Avoid ingesting lake water.
  • Avoid contact with algae blooms, which generally appear as a scum on the water surface.
  • Shower with soapy water after swimming.
  • Bring clean water for your dog to drink on hikes or other outings.
  • Keep dogs close and on a leash.
  • Bathe your dog with soapy water as soon as possible after a swim.

People who access Indiana's reservoirs from resource management areas, small boat launching sites, fishing access parking lots or unofficial entry points such as dead-end county roads and other remote locations should be especially cautious before entering the water. Blue-green alga is most often found in shallow water or coves and bays where water movement is limited.

Weather conditions, wind direction, water temperature, precipitation, can quickly change the blue-green algae cell count and the concentration of toxins in an area.

Hoosiers can help reduce blue-green algae blooms by choosing phosphorus-free fertilizer, limiting the use of fertilizer around waterways, and regularly maintaining septic systems.