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Beware of toxic algae in water ways in county
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Deep into the dog days of summer, one of the favorite local pastimes is cooling off in the bodies natural waterways that flow through the South County or bodies of water that surround it.

But on Tuesday, San Joaquin County Health Officials warned that before people decide to leave the comfort of their watercraft or the safety of the shoreline, they should check to make sure that the water on the San Joaquin River or other natural bodies of water that they’re about to swim into isn’t full of toxic algae blooms that can make people sick.

According to the release, the algae blooms – which are commonly referred to as blue-green algae or by the medical term cyanobacteria – can look like green, blue-green, white, or brown foam or scum that floats on the top of the water. Parents with young children are encouraged to keep an eye out for the blooms since children are particularly vulnerable since they play near the shoreline, tend to drink more water while swimming than adults, and are of a smaller body size, according to the release from San Joaquin County Public Health Services. 

“The best way to avoid illness is to exercise caution and observe signage that warns visitors to avoid active algal blooms,” San Joaquin County Public Health Officer Dr. Kismet Baldwin advised in a release. 

Humans that are exposed to blue-green algae may develop rashes or other skin irritations, allergy-like reactions like runny nose or sore throat, and potentially sharp, severe stomach problems like diarrhea and vomiting if ingested. Other possible symptoms and health concerns include potential liver damage, numb limbs, tingling fingers or toes or dizziness.

Animals that are exposed may exhibit weakness or staggering, difficulty breathing, convulsions, vomiting and diarrhea and possibly even death if not treated. 

Residents are encouraged to ensure that pets and livestock do not drink water that may have algae scums or mats that are visible, and to get medical treatment right away if they believe they their family members, their pets, or their livestock may have poisoned by the toxins that are a part of the algae blooms – which are exacerbated by the warm temperatures that are expected to continue for more than another month. 

Those wishing for more information about where harmful algal blooms have been reported can check the State of California’s harmful algal bloom portal at, and those that encounter a bloom they feel may be toxic are encouraged to report it at 

To contact reporter Jason Campbell email or call 209.249.3544.