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Type of Advisory
Recreational Public Health
No Contact
Drinking Water: Do Not Drink
Drinking Water: Do Not Use
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About This Map
Harmful Algal Bloom Advisories are issued at Ohio State Park Beaches or at Public Water Systems where Harmful Algal Blooms have been identified. This map is updated Monday through Friday and displays only active advisories. read more...
Imagery
No active advisories for harmful algal blooms at state park beaches or public water systems at this time.


Harmful Algal Bloom Advisory Levels


The Recreational Public Health Advisory - A Recreational Public Health Advisory sign will be posted at beaches when toxin levels exceed the recommended threshold, warning individuals who are elderly or very young and people with compromised immune systems that swimming or wading is not recommended.
A No Contact Advisory - A No Contact Advisory sign will be posted when toxin levels exceed the recommended threshold and there are one or more probable cases of human illness or pet deaths attributable to HABs. This sign will warn people that unsafe toxins are present in the water and to avoid any contact.
Drinking Water Advisory - Do Not Drink If microcystin, anatoxin-a, cylindrospermopsin or saxitoxin is found above drinking water thresholds in the finished water of a public water system, the water system will issue a public notice for a Do Not Drink Advisory. The public water system may end a Do Not Drink Advisory when algal toxin levels are below the drinking water thresholds in two consecutive samples collected at least 24 hours apart.
Drinking Water Advisory - Do Not Use If microcystin, anatoxin-a, cylindrospermopsin or saxitoxin is found above drinking water thresholds in the finished water of a public water system, the water system will issue a public notice for a Do Not Use Advisory. The public water system may end a Do Not Use Advisory when algal toxin levels are below the drinking water thresholds in two consecutive samples collected at least 24 hours apart.



Numeric Cyanotoxin Thresholds
All threshold values are reported in ug/L
Type of AdvisoryMicrocystin *Anatoxin-aCylindrospermopsinSaxitoxin*
Recreational Public Health Advisory68050.8
Recreational No Contact Advisory**20300203
Drinking Water: Do Not Drink Advisory12010.2
Drinking Water: Do Not Use Advisory20300203
*Microcystin and Saxitoxin thresholds are intended to be applied to total concentrations of all reported cogeners of those toxins.
**A No Contact Advisory is issued when toxin levels exceed the recommended threshold and there are one or more probable cases of human illness or pet deaths attributable to HABs.


Notes: ppb - parts per billion; ug/L - micrograms per liter; Microcystin, Anatoxin-a, Cylindrospermopsin and Saxitoxin are the Cyanotoxins tested for at Ohio state park beaches and at public water systems.