(5-25-25) Three locations on Grand Lake have been given ‘red flag‘ advisories by the Ohio Department of Health. Grand Lake joins 13 other locations on the Beach Guard list from around Ohio. The sampling of the three locations took place on May 20th and May 21st.

Sample DateIndicator SpeciesMeThod TypeMeThod ContextLocationValueQualifierStatistical Base
05/21/24MicrocystinMicrocystins-ADDA ELISAGrand Lake St. Marys – Main West Monitoring Location23.2 ug/lSpatial Composite Sample
05/20/24E. coliNot SpecifiedGrand Lake St. Marys – Main West Monitoring Location9.7 cfu/100mlIndividual Sample
Grand Lake – Grand Lake St. Marys – Main West
Sample DateIndicator SpeciesMeThod TypeMeThod ContextLocationValueQualifierStatistical Base
05/21/24MicrocystinMicrocystins-ADDA ELISAGrand Lake St. Marys – Windy Point13.7 ug/lSpatial Composite Sample
05/20/24E. coliNot SpecifiedGrand Lake St. Marys – Windy Point77.1 cfu/100mlIndividual Sample
Grand Lake – Grand Lake St. Marys – Windy Point
Sample DateIndicator SpeciesMeThod TypeMeThod ContextLocationValueQualifierStatistical Base
05/21/24MicrocystinMicrocystins-ADDA ELISAGrand Lake St. Marys – Camp Monitoring Location9.4 ug/lSpatial Composite Sample
05/20/24E. coliNot SpecifiedGrand Lake St. Marys- Camp Monitoring Location31.3 cfu/100mlIndividual Sample
Grand Lake – Grand Lake St. Marys – Camp

Avoid all contact with the water. Algal toxins have been found at unsafe levels. Swimming and wading are not recommended. Keep pets away. For more information go to www.ohioalgaeinfo.com or call 1-866-644-6224