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Algal Blooms

There are no confirmed Harmful Algal Blooms (HABs) in Lake Mahopac 2019.  Currently, there are no suspicious blooms reported since June 2019. 
Not all Algae blooms are toxic.  The DEC Harmful Algal Blooms (HABs) has photos of toxic and non-toxic blooms.  Please refer to Helpful links below for more details about Harmful Blue-green Algae Blooms on how to identify it and what to do if you come in contact with it.
When you look at the DEC notification site about Harmful Algal Blooms (HABs) please be aware of the bloom status.  When a reported bloom is indicated it doesn't mean it impacts the entire lake.
  • Suspicious Bloom: DEC staff determine that conditions fit the description of a cyanobacteria bloom (HAB), based on visual observations and/or digital photographs. It is not known if there are harmful toxins or other compounds in the water. The bloom may be present in all or part of the waterbody. Laboratory analysis has not been done to determine if this is a HAB. Cyanobacteria are irritants to some people even if toxins are not present so all contact with the bloom should be avoided. Blooms may be present in all or part of the waterbody.
  • Confirmed Bloom: Water sampling results have confirmed the presence of a cyanobacteria HAB which MAY produce toxins or other harmful compounds.
  • Confirmed with High Toxins Bloom: Water sampling results have confirmed that there are toxins present in enough quantities to potentially cause health effects when people and animals come in contact with the water through swimming or drinking.