MADERA COUNTY, Calif. (KSEE/KGPE) – A recreational advisory has been issued at Madera County’s Hensley Lake due to a Harmful Algal Bloom (HABs) in the water, according to the Central Valley Regional Water Quality Control Board.

Fishermen and recreational users are urged to stay out of Hensley Lake after the water tested positive for HABs, which pose an elevated risk.

Recreators are encouraged to follow these steps:

• Stay out of the water until further notice, including watercraft.
• Do not let pets and other animals drink or go into the water, or go near the scum.
• Stay away from scum, and cloudy or discolored water.
• Do not eat fish or shellfish from this water.
• Do not use this water for drinking or cooking. Boiling or filtering will not make the water safe.

Central Valley Water Boards officials say the cyanobacteria bloom was identified visually and through laboratory testing of water and algal scum samples. This can produce potent toxins.

Health Risks Associated with HABs:

  • Skin inflammation (itchy skin and rashes)
  • Gastrointestinal distress
  • Headaches
  • Agitation and weakness or abnormal breathing if HAB material is swallowed while swimming.

Dogs and children are at high risk because of their small body size, increased potential of swallowing water while swimming, and their tendency to stay in the water for longer periods.

If exposure is suspected, officials advise washing children and dogs immediately.

Get medical treatment immediately if you think that you, your pet, or your livestock have gotten sick after going in the water, and make sure to contact the local county public health department.

To report a bloom visit: or call 1 (844) 729-6466 (toll-free).