Algae Bloom Information

The Ohio Environmental Protection Agency (EPA) has a site: in Ohio where the public can view a list of current advisories or sampling data, report potential algal blooms, and get tips about Harmful Algal Blooms (HABs).


The State has also developed standards for the posting of Ohio Recreational Use HAB Advisories. There are three recreational use advisories:

  • An algae bloom advisory will be posted for a recreational contact area once an algal bloom has been identified and the State has confirmed it is a harmful algal bloom capable of producing toxin. The public would be advised not to ingest water and avoid contact with surface scum.
  • The public health advisory would be posted when tests conclude microcystin levels are at least six parts per billion (ppb). At this point, the public would be advised that swimming and wading are not recommended, water should not be swallowed and surface scum should be avoided.
  • A no-contact advisory would recommend the public to avoid all contact with the water at that location. A no contact advisory would be posted if test results show microcystin levels at least 20 ppb and there has been a report of human illness or pet death. If a no contact advisory is posted for a recreational contact area, the State may sample the lake to determine if an open water no contact advisory should be posted.