Harmful Algal Blooms

Cyanobacteria, often called blue-green algae, are commonly found in Ohio lakes, ponds, and slow-moving rivers. Although many species of blue-green algae do not produce toxins, some species of blue-green algae can cause Harmful Algal Blooms (HABs).

HABs occur when there is a shallow body of fresh water, warm temperatures, sunlight, and excessive amounts of nutrients (phosphorus and nitrogen) in the water. Phosphorus and nitrogen are commonly found in animal and human wastes and in fertilizers.

Under the right conditions, the numbers of blue-green algae can dramatically increase or "bloom" in a body of water. Some of these HABs are visible as thick mats or scum on the surface of the water. These mats can vary in color, including bluish-green, bright green, or even red or maroon.

Additional information is found on the Ohio Department of Health’s website

Ohio Algal Information for Recreational Waters

Although most blooms are green algae and not harmful, there are some that are actually a type of cyanobacteria that have the ability to produce toxins – called harmful algal blooms (HABs) http://epa.ohio.gov/habalgae.aspx.

WHEN IN DOUBT, STAY OUT!

Remember, you can still boat, fish and recreate in Ohio’s lakes, streams and rivers. Just be aware that HABs exist. We hope the information here will give you a better idea of what HABs can look like and provide you with the information you need to safely enjoy Ohio's waterways.

For additional information click here:

LINKS

HAB General Factsheet

Report HABs in Ohio Waters

If you see surface scum or something that looks like blue-green algae at a state park lake beach, report it to Ohio EPA by completing the report form and emailing here.